Next week; February 2nd.
10 questions + 1 bonus question. 10 points each, bonus = 5 points. Remember this!
Choose 7 questions. 70 points total.
Equals 30% of final mark. MUST pass both report and final test.
Not open book.
Good luck - don't panic!
Wednesday, January 26, 2011
January 26th class
Conservation History on the Great Barrier Reef:
The Great Barrier Reef = GBR
Great Barrier Reef Marine Park
Outline
Background
Why was rezoning of GBR necessary?
Representative Areas Program (RAP) (only part of solution)
Phase 1 and 2
Final zoning plan
Implementation phase
Monitoring
Other actions
Reef Water Quality Plan
Reducing fishing and policing
The Great Barrier Reef = GBR
345,000 km2
> 2000 km long
2900 separate reefs
> 900 islands
Formation of the Park
Late 1960’s – early 1970’s—much agitation for a park, reinforced by plans to mine Ellison Reef (off Innisfail)
Politicians promised that the GBR should be protected as a Park
Park established in 1975, under Great Barrier Reef Marine Park Act (Federal Parliament Act)
Implementation
Park boundaries are non-negotiable, can only be changed by Act of Parliament
No mining within the Park
Development & implementation of zoning plans is a Federal responsibility
Day to day management is the responsibility of Queensland Parks & Wildlife Service
Zoning Plans
First areas to be zoned Capricorn and Bunker, finished in 1977
Subsequently the other regions were zoned
Zoning plans reviewed at regular intervals, with public participation, and plans changed over time and even the type of zones changed
GBRMPA
Based in Townsville
Responsible to Minister for Science
Issues permits and licences, including those for scientific research
GBR declared World Heritage Area in 1981— such listing requires regular report card to ensure the reef is being maintained
During the 1990’s
Increasing use of the reef by tourists
Increased scientific knowledge of the reef
Increasing awareness of the connectivity of reefs (mass spawning)
Increasing evidence of decline of some habitats, especially inshore
The Great Barrier Reef Is ‘Under Pressure’
Downstream effects of land use (water quality issues)
Coral bleaching
Coastal developments
Increasing fishing effort and impacts
Shipping & pollution incidents
Increasing tourism and recreation
Trends in Regional Biodiversity Are Negative
Fishing effort increasing substantially in intensity & spatial extent (coral trout fishery—effort x2 since 1995; shark catch x5 since 1991)
Turtles–all 6 species threatened; 2 are endangered (Loggerhead and Olive Ridley)
Dugong population south of Cooktown has declined >90% since mid-1980’s
Humpbacks listed as vulnerable; other cetaceans (Irrawaddy & Indo-Pacific hump-backed dolphins) listed as rare
Trends for most species unknown
GBR Is Not Isolated From World Trends
10% of world’s reefs destroyed or severely degraded
58% of world’s reefs potentially threatened
70% reefs already degraded in Indonesia & Philippines
On current trends 70% of the world’s reefs will have gone in 40 years
Minimising the
‘Pressures’
Downstream effects of land use ==> Reef Water Quality Action Plan (results not immediate)
Coastal developments ==> Aquaculture Regs; GBRMP permit requirements
Increasing fishing effort and impacts ==> Queensland FS fisheries management plans (ECTMP, Reef Line)
Minimising the
‘Pressures’
Shipping & pollution incidents ==> Australia Marine Shipping Authority shipping review, compulsory pilotage, mandatory reporting, etc
Increasing tourism and recreation ==> PoMs; new tourism framework
Threatened species ==> new policies; species recovery plans; seasonal closures, RAP
Protecting biodiversity ==> RAP
Why was rezoning of the GBR necessary?
Queenslanders depend on the GBR
Important for economy—tourism, commercial fishing, recreational fishing, shipping
Important for Traditional Owners—connection with Sea Country
Important for communities—relaxation, lifestyles
>90% Australians (including Queenslanders) wanted more no-take zones
Important for building knowledge—education, research
Better protection = insurance for all these values
Connectivity in the GBR
An overview of RAP
Representative examples of the entire diversity of habitats protected
RAP reviewed the existing zoning of the Marine Park
RAP attempted to minimise negative impacts for users and stakeholders while aiming to achieve protection of biodiversity
RAP has meant an increase in Green Zones to protect biodiversity
RAP is a crucial part of the solution to a complex problem
Other Issues Addressed During Rezoning
Some current zoning plans had been in existence for 16 years
Ensured consistent zone names and zone provisions throughout GBR
Coastal areas zoned for first time
Clearer delineation of zone boundaries (GPS co-ordinates)
Developing the Zoning Plan
The Zoning Plan was developed using environmental, economic, and social information
Clear Principles on how to use the environmental and social information were followed
These principles were set out in the first round of community participation (CP1)
Environmental Information
Bioregions
Bioregions were mapped between 1999 and 2002 using expert knowledge and best available data and methods
30 reef bioregions 40 non-reef bioregions
Many bioregions previously lacked adequate protection
At least 20% of each bioregion included in a no-take zone
The GBR Marine Park
Non reef bioregions
Environmental Information
Other key issues:
Special and unique places
Critical habitats such as turtle nesting sites
Deep & shallow water sea-grass, fish spawning sites etc.
Special and unique places
Critical turtle nesting areas
Environmental Information
Biophysical Principles guided selection and use of environmental information
The Principles :
were developed by independent reef scientists
published in CP1
said that at least 20% of each bioregion had to be in no-take zones
No-take zones must be
large
arranged to form viable network, allowing connectivity, provides insurance policy
Social & Economic Information
Sources:
Recreational fishing diaries, and tag and release records
Commercial fishing log-books
The location of boat-ramps and coastal developments
Historic ship-wrecks
Visitor use data
Over 10,000 submissions received in Phase 1 & >21,000 in Phase 2
All submissions read to identify community issues
All submissions were taken into account
Recreational fishing sites
Commercial fishing values
Using Social Information
Social, Economic, Cultural and Management Principles were:
developed by an independent panel of experts
published in Community Phase 1
The SEC Principles attempted to
minimise impact on existing users of the Marine Park
be fair—ie not impacting on one group or community more than another
but needed a Zoning plan easy to enforce
Previous Zoning
Previous Zoning, plus Trawl Plans
New green zones—environmental data only
Green zones—using economic data too
Green zones—revising boundaries
The Plan
What Does This Plan Do?
Provides strong, medium and long-term protection for future generations
Green zones mean more and bigger fish
Green zone spill-over, better fishing for reef communities
Natural values which attracts tourists and $ will be maintained
Protects at least 20% of each bioregion, special and unique areas, important habitats, and nesting areas—over 33% achieved
Phases of RAP
Classification (map biodiversity)
Reviewed existing protection
informal consultation with user groups
formal Community Participation phase 1
Identification of possible network options
Selection of most acceptable network
Draft zoning plan
formal Community Participation phase 2 (over 21,000 submissions)
Ministerial & parliamentary approval March 2004
Implemented July 1st 2004
Representative Areas Program
A new and effective network of ‘no-take’ areas representative of all bioregions helps to:
maintain biological diversity
maintain ecological processes and systems
provide an ecological safety margin, and if necessary, enable species and habitats to recover
ensure viable and sustainable industries
Current Status
Distribution of information and many maps to fishers, tourist operators, dive, boat and bait shops
Revised maps at boat ramps
Sorting out current permits in relation to new zoning, research stations issuing permits
Working with GPS manufacturers to incorporate zoning plans into charts, some available
Website available to download zoning plans for particular areas of interest
Related Activities
Reef Water Quality Protection Plan-implemented
Fisheries related: Reduction of number of fishing boats
Reduction in areas where trawling allowed
compensation being paid
Increased surveillance, penalties imposed
Dugong protected areas and reduce netting areas
Qld zoned adjacent coastal parks
Recognition of RAP
Authority awarded a Eureka Prize for Biodiversity Research and Banksia Environmental Award
WWF Australia acknowledges its importance for conserving biodiversity
Recognition overseas of importance of this approach to marine park management
Best practise
Relevance to Other Areas
Zoning with scientific basis
Problems facing the GBR faced by all reefal areas
Methods for zoning multi-use parks relevant to all areas in Australia and elsewhere
Such community involvement results in ownership and stewardship of the reef– schools adopting reefs, communities becoming effective policers
Other Management Strategies
Reef Water Quality Protection Plan
being implemented but ongoing and results will take years to be apparent
Reduction in number of fishing licences, compensation being paid
Increasing policing and enforcement
Global warming— the big question
increased rates of bleaching
increased cyclones activity
What is the long term future for the GBR?
Points to consider for Okinawa/Ryukyu Islands:
Only three major governments (National, 2 Prefectural).
However, management is very ambiguous.
Local fisheries have strong power; no no-take zones anywhere in Japan, aquaculture common.
Competing interests within national government have different agendas (Construction, Environment).
National laws for parks weak.
Okinawa Prefecture likely has strong wishes, but needs money from National government.
The Great Barrier Reef = GBR
Great Barrier Reef Marine Park
Outline
Background
Why was rezoning of GBR necessary?
Representative Areas Program (RAP) (only part of solution)
Phase 1 and 2
Final zoning plan
Implementation phase
Monitoring
Other actions
Reef Water Quality Plan
Reducing fishing and policing
The Great Barrier Reef = GBR
345,000 km2
> 2000 km long
2900 separate reefs
> 900 islands
Formation of the Park
Late 1960’s – early 1970’s—much agitation for a park, reinforced by plans to mine Ellison Reef (off Innisfail)
Politicians promised that the GBR should be protected as a Park
Park established in 1975, under Great Barrier Reef Marine Park Act (Federal Parliament Act)
Implementation
Park boundaries are non-negotiable, can only be changed by Act of Parliament
No mining within the Park
Development & implementation of zoning plans is a Federal responsibility
Day to day management is the responsibility of Queensland Parks & Wildlife Service
Zoning Plans
First areas to be zoned Capricorn and Bunker, finished in 1977
Subsequently the other regions were zoned
Zoning plans reviewed at regular intervals, with public participation, and plans changed over time and even the type of zones changed
GBRMPA
Based in Townsville
Responsible to Minister for Science
Issues permits and licences, including those for scientific research
GBR declared World Heritage Area in 1981— such listing requires regular report card to ensure the reef is being maintained
During the 1990’s
Increasing use of the reef by tourists
Increased scientific knowledge of the reef
Increasing awareness of the connectivity of reefs (mass spawning)
Increasing evidence of decline of some habitats, especially inshore
The Great Barrier Reef Is ‘Under Pressure’
Downstream effects of land use (water quality issues)
Coral bleaching
Coastal developments
Increasing fishing effort and impacts
Shipping & pollution incidents
Increasing tourism and recreation
Trends in Regional Biodiversity Are Negative
Fishing effort increasing substantially in intensity & spatial extent (coral trout fishery—effort x2 since 1995; shark catch x5 since 1991)
Turtles–all 6 species threatened; 2 are endangered (Loggerhead and Olive Ridley)
Dugong population south of Cooktown has declined >90% since mid-1980’s
Humpbacks listed as vulnerable; other cetaceans (Irrawaddy & Indo-Pacific hump-backed dolphins) listed as rare
Trends for most species unknown
GBR Is Not Isolated From World Trends
10% of world’s reefs destroyed or severely degraded
58% of world’s reefs potentially threatened
70% reefs already degraded in Indonesia & Philippines
On current trends 70% of the world’s reefs will have gone in 40 years
Minimising the
‘Pressures’
Downstream effects of land use ==> Reef Water Quality Action Plan (results not immediate)
Coastal developments ==> Aquaculture Regs; GBRMP permit requirements
Increasing fishing effort and impacts ==> Queensland FS fisheries management plans (ECTMP, Reef Line)
Minimising the
‘Pressures’
Shipping & pollution incidents ==> Australia Marine Shipping Authority shipping review, compulsory pilotage, mandatory reporting, etc
Increasing tourism and recreation ==> PoMs; new tourism framework
Threatened species ==> new policies; species recovery plans; seasonal closures, RAP
Protecting biodiversity ==> RAP
Why was rezoning of the GBR necessary?
Queenslanders depend on the GBR
Important for economy—tourism, commercial fishing, recreational fishing, shipping
Important for Traditional Owners—connection with Sea Country
Important for communities—relaxation, lifestyles
>90% Australians (including Queenslanders) wanted more no-take zones
Important for building knowledge—education, research
Better protection = insurance for all these values
Connectivity in the GBR
An overview of RAP
Representative examples of the entire diversity of habitats protected
RAP reviewed the existing zoning of the Marine Park
RAP attempted to minimise negative impacts for users and stakeholders while aiming to achieve protection of biodiversity
RAP has meant an increase in Green Zones to protect biodiversity
RAP is a crucial part of the solution to a complex problem
Other Issues Addressed During Rezoning
Some current zoning plans had been in existence for 16 years
Ensured consistent zone names and zone provisions throughout GBR
Coastal areas zoned for first time
Clearer delineation of zone boundaries (GPS co-ordinates)
Developing the Zoning Plan
The Zoning Plan was developed using environmental, economic, and social information
Clear Principles on how to use the environmental and social information were followed
These principles were set out in the first round of community participation (CP1)
Environmental Information
Bioregions
Bioregions were mapped between 1999 and 2002 using expert knowledge and best available data and methods
30 reef bioregions 40 non-reef bioregions
Many bioregions previously lacked adequate protection
At least 20% of each bioregion included in a no-take zone
The GBR Marine Park
Non reef bioregions
Environmental Information
Other key issues:
Special and unique places
Critical habitats such as turtle nesting sites
Deep & shallow water sea-grass, fish spawning sites etc.
Special and unique places
Critical turtle nesting areas
Environmental Information
Biophysical Principles guided selection and use of environmental information
The Principles :
were developed by independent reef scientists
published in CP1
said that at least 20% of each bioregion had to be in no-take zones
No-take zones must be
large
arranged to form viable network, allowing connectivity, provides insurance policy
Social & Economic Information
Sources:
Recreational fishing diaries, and tag and release records
Commercial fishing log-books
The location of boat-ramps and coastal developments
Historic ship-wrecks
Visitor use data
Over 10,000 submissions received in Phase 1 & >21,000 in Phase 2
All submissions read to identify community issues
All submissions were taken into account
Recreational fishing sites
Commercial fishing values
Using Social Information
Social, Economic, Cultural and Management Principles were:
developed by an independent panel of experts
published in Community Phase 1
The SEC Principles attempted to
minimise impact on existing users of the Marine Park
be fair—ie not impacting on one group or community more than another
but needed a Zoning plan easy to enforce
Previous Zoning
Previous Zoning, plus Trawl Plans
New green zones—environmental data only
Green zones—using economic data too
Green zones—revising boundaries
The Plan
What Does This Plan Do?
Provides strong, medium and long-term protection for future generations
Green zones mean more and bigger fish
Green zone spill-over, better fishing for reef communities
Natural values which attracts tourists and $ will be maintained
Protects at least 20% of each bioregion, special and unique areas, important habitats, and nesting areas—over 33% achieved
Phases of RAP
Classification (map biodiversity)
Reviewed existing protection
informal consultation with user groups
formal Community Participation phase 1
Identification of possible network options
Selection of most acceptable network
Draft zoning plan
formal Community Participation phase 2 (over 21,000 submissions)
Ministerial & parliamentary approval March 2004
Implemented July 1st 2004
Representative Areas Program
A new and effective network of ‘no-take’ areas representative of all bioregions helps to:
maintain biological diversity
maintain ecological processes and systems
provide an ecological safety margin, and if necessary, enable species and habitats to recover
ensure viable and sustainable industries
Current Status
Distribution of information and many maps to fishers, tourist operators, dive, boat and bait shops
Revised maps at boat ramps
Sorting out current permits in relation to new zoning, research stations issuing permits
Working with GPS manufacturers to incorporate zoning plans into charts, some available
Website available to download zoning plans for particular areas of interest
Related Activities
Reef Water Quality Protection Plan-implemented
Fisheries related: Reduction of number of fishing boats
Reduction in areas where trawling allowed
compensation being paid
Increased surveillance, penalties imposed
Dugong protected areas and reduce netting areas
Qld zoned adjacent coastal parks
Recognition of RAP
Authority awarded a Eureka Prize for Biodiversity Research and Banksia Environmental Award
WWF Australia acknowledges its importance for conserving biodiversity
Recognition overseas of importance of this approach to marine park management
Best practise
Relevance to Other Areas
Zoning with scientific basis
Problems facing the GBR faced by all reefal areas
Methods for zoning multi-use parks relevant to all areas in Australia and elsewhere
Such community involvement results in ownership and stewardship of the reef– schools adopting reefs, communities becoming effective policers
Other Management Strategies
Reef Water Quality Protection Plan
being implemented but ongoing and results will take years to be apparent
Reduction in number of fishing licences, compensation being paid
Increasing policing and enforcement
Global warming— the big question
increased rates of bleaching
increased cyclones activity
What is the long term future for the GBR?
Points to consider for Okinawa/Ryukyu Islands:
Only three major governments (National, 2 Prefectural).
However, management is very ambiguous.
Local fisheries have strong power; no no-take zones anywhere in Japan, aquaculture common.
Competing interests within national government have different agendas (Construction, Environment).
National laws for parks weak.
Okinawa Prefecture likely has strong wishes, but needs money from National government.
January 19th class
Outline
1. Review of dangers facing coral reefs (bleaching!).
2. How to stop bleaching (?).
3. Red coral in the Mediterranean.
4. The importance of fish and mangroves to coral reefs.
5. Community conservation in the Philippines.
6. Conclusions.
Part 1 - Review of dangers facing coral reefs (bleaching!)
Dangers facing coral reefs
Global warming is raising the temperature of the ocean; this kills corals - “coral bleaching”.
Also, as the oceans become more acidic, it is more difficult for corals to make their skeletons.
Perhaps 90% of coral reefs will be dead by 2050.
Crown-of-thorns starfish outbreaks
Dynamite and cyanide fishing
Coral bleaching: Images from Phuket, Thailand 2010
Background
Corals (and many other coral reef invertebrates) are in symbiosis with Symbiodinium (zooxanthellae).
This symbiosis allows these invertebrates to live in nutrient-deficient sub-tropical and tropical waters.
Algal-animal symbioses are a successful strategy that has been repeated many times in evolution.
Weak point
Despite the success of this symbiosis, it has one very serious weak point:
Symbiodinium are very sensitive to low and high temperatures.
<18°C, and >30°C.
Coral bleaching
When temperatures are abnormal for the holobiont, stress occurs.
With this stress, thylakoids in Symbiodinium begin to break down; the symbiont begins to poison the host.
Corals lose their symbionts, either through cell-death, or by expelling them.
Hosts turn white = coral bleaching.
Predicting coral bleaching
The NOAA (USA) has spent much time on predicting bleaching.
Can now predict bleaching very accurately.
These tools available for free on the internet.
Vocabulary
SST=sea surface temperature
DHW=degree heating weeks
Daily max=expected average maximum SST for a certain day
MMM=maximum monthly mean, average temperature of the hottest month
SST anomolies
Observed SST – daily max SST
Can be used to see what location is hotter than usual.
Coral bleaching HotSpot
Predicts what areas have thermal stress that can cause/contribute to coral bleaching.
HotSpot=observed SST - MMM
Degree heating week (DHW)
However, it is not just anomolies and hotspots that cause coral bleaching.
The total stress from the past weeks is important. One hot day does not kill most coral!
DHW=0.5*(sum of previous 24 HotSpot reports), where HotSpots <1.0°C are not counted.
Example: 1 week of 2°C higher than normal = 2 weeks of 1°C higher than normal.
DHW >8.0 usually can cause coral death.
Thailand’s situation
Very high DHW on both sides of the Malaysian Peninsula.
Made worse by no cold temperatures last winter.
Also, lack of wind (“doldrums”) causes more solar/UV stress, which makes bleaching worse.
Ko Racha
Ko Tao
Ko Samet
Thank you.
Part 2 -
How to stop bleaching (?)
West & Salm 2003
What factors help corals against bleaching?
Reviewed all research up until 2003.
Many examples of resistance to or recovery from bleaching.
Many factors contribute to resistance.
Can be included in management plans.
Cumulative stresses worse than one stressor.
Part 3 - Red coral in the Mediterranean
Red coral
Corallium rubrum is a precious coral in the Mediterranean.
Found 10 -250 m.
Harvested for long time, over-exploited.
Harvest reduced 66% in last 15 years.
Population structure
Two population types, large deep colonies and shallow small colonies.
Large drop off in shallow water at age 4, due to sponges and collection.
Genetic distance becomes significant at 100s of kms.
Thus, preservation of numerous populations needed.
Management on regional scale needed.
Must avoid local extinctions.
Conservation recommendations
Must be managed at national and international scales.
Only policy that works for such species.
Set minimum colony sizes, maximum yield per area, harvesting seasons.
Mumby et al. 2004
Reef fish often use mangroves as nurseries.
But can use other environments, not confined.
Also, despite deforestation, other pressures (fishing, larval supply) likely larger.
Management should include connected habitats, not islands of each type.
Future destruction of mangroves will have negative influence on reef.
Mumby et al. 2007
Caribbean reefs have damage from loss of Diadema antillarum and two species of coral.
“Sick” reefs characterized by macroalgae.
Can macroalgae be reversed? Or is it a stable state?
Used computer modeling and simulation.
Showed reefs can easily change to other states once D. antillarum died off.
With only parrotfish as grazers, small negative change in parrotfish numbers results in macroalgae blooms.
Coral becomes unstable state with low grazing.
Regular impact of hurricanes worsens with lack of grazers (fish and urchins).
Modeling useful for conservation targets.
Part 5 - Community conservation of coral reefs
History
Philippines consist of 7000+ islands.
Centuries have used reefs for livelihood.
Since 1970s, threatened by over-exploitation and destructive fishing methods.
Conservation started in 1974. Many projects failed.
Politics tied to conservation.
Local governments have authority but not knowledge or budget.
To be successful, combination of local and national people.
Within local group, must include users of reef; fishermen, resort owners, coastal residents, scuba divers.
Start of conservation
MDCP started in 1986 on three islands (62-166 households); Apo, Pamilacan, Balicasag.
All had less fish catch, increasing destruction and poverty.
MCDP plan
Marine reserves with buffer areas to increase number and diversity fish.
Development of local knowledge and alternative work.
Community center.
Outreach and replication program.
MCDP steps
Integration into community.
Education - marine ecology and resource management.
Group building, formalizing, strengthening.
Results
Apo & Pamilacan remain strong.
Balicasag protection groups somewhat weakened due to large PTA resort and less local “ownership”.
PTA has good points too.
All islands have stronger municipal laws now.
Results
Local fisherman believe sanctuary has helped.
Comparison of 1985-86 data with 1992 shows increases in fish, stable coral cover.
Conclusions
MPAs work on small islands by preventing destructive fishing and making locals understand value of conservation.
Small islands easier to implement plans.
Immediate benefits must be seen.
Baseline data necessary.
Local fishermen help with MPA location decisions.
Conclusions
Locals must understand how problem and answer related.
Management groups must have respected members.
Link with all potentially helpful groups.
All plans vulnerable to politics and outside groups.
Part 6 - Conclusions
Towards the future
In the future, more conservation plans will be implemented.
The gap between well protected areas and those not protected will widen.
Towards the future
Very few non-protected reefs will survive.
Thanks!
References cited:
1. West & Salm. 2003. Resistance and resilience to coral bleaching. Conservation Biol 17: 956-967.
2. Santangelo & Abbiati. 2001. Red coral: conservation and management of an over-exploited Mediterranean species. Aquatic Conserv Mar Freshwater Ecosys 11: 253-259.
3. Hughes et al. 2002. Biodiversity hotspots, centres of endemicity, and the conservation of coral reefs. Ecol Let 5: 775-784.
4. Roberts et al. 2002. Marine biodiversity hotspots and conservation priorities for tropical reefs. Science 295: 1280-1284. 8. 5. 5. Mumby et al. 2004. Mangroves enhance the biomass of coral reef fish communities in the Caribbean. Nature 427: 533-536. 9.
6. Mumby et al. 2007. Thresholds and the resilience of Caribbean coral reefs. Nature 450: 98-101.
7. White & Vogt. 2000. Philippine coral reefs under threat: lessons learned after 25 years of community-based reef conservation. Mar Poll Bull 40: 537-550.
1. Review of dangers facing coral reefs (bleaching!).
2. How to stop bleaching (?).
3. Red coral in the Mediterranean.
4. The importance of fish and mangroves to coral reefs.
5. Community conservation in the Philippines.
6. Conclusions.
Part 1 - Review of dangers facing coral reefs (bleaching!)
Dangers facing coral reefs
Global warming is raising the temperature of the ocean; this kills corals - “coral bleaching”.
Also, as the oceans become more acidic, it is more difficult for corals to make their skeletons.
Perhaps 90% of coral reefs will be dead by 2050.
Crown-of-thorns starfish outbreaks
Dynamite and cyanide fishing
Coral bleaching: Images from Phuket, Thailand 2010
Background
Corals (and many other coral reef invertebrates) are in symbiosis with Symbiodinium (zooxanthellae).
This symbiosis allows these invertebrates to live in nutrient-deficient sub-tropical and tropical waters.
Algal-animal symbioses are a successful strategy that has been repeated many times in evolution.
Weak point
Despite the success of this symbiosis, it has one very serious weak point:
Symbiodinium are very sensitive to low and high temperatures.
<18°C, and >30°C.
Coral bleaching
When temperatures are abnormal for the holobiont, stress occurs.
With this stress, thylakoids in Symbiodinium begin to break down; the symbiont begins to poison the host.
Corals lose their symbionts, either through cell-death, or by expelling them.
Hosts turn white = coral bleaching.
Predicting coral bleaching
The NOAA (USA) has spent much time on predicting bleaching.
Can now predict bleaching very accurately.
These tools available for free on the internet.
Vocabulary
SST=sea surface temperature
DHW=degree heating weeks
Daily max=expected average maximum SST for a certain day
MMM=maximum monthly mean, average temperature of the hottest month
SST anomolies
Observed SST – daily max SST
Can be used to see what location is hotter than usual.
Coral bleaching HotSpot
Predicts what areas have thermal stress that can cause/contribute to coral bleaching.
HotSpot=observed SST - MMM
Degree heating week (DHW)
However, it is not just anomolies and hotspots that cause coral bleaching.
The total stress from the past weeks is important. One hot day does not kill most coral!
DHW=0.5*(sum of previous 24 HotSpot reports), where HotSpots <1.0°C are not counted.
Example: 1 week of 2°C higher than normal = 2 weeks of 1°C higher than normal.
DHW >8.0 usually can cause coral death.
Thailand’s situation
Very high DHW on both sides of the Malaysian Peninsula.
Made worse by no cold temperatures last winter.
Also, lack of wind (“doldrums”) causes more solar/UV stress, which makes bleaching worse.
Ko Racha
Ko Tao
Ko Samet
Thank you.
Part 2 -
How to stop bleaching (?)
West & Salm 2003
What factors help corals against bleaching?
Reviewed all research up until 2003.
Many examples of resistance to or recovery from bleaching.
Many factors contribute to resistance.
Can be included in management plans.
Cumulative stresses worse than one stressor.
Part 3 - Red coral in the Mediterranean
Red coral
Corallium rubrum is a precious coral in the Mediterranean.
Found 10 -250 m.
Harvested for long time, over-exploited.
Harvest reduced 66% in last 15 years.
Population structure
Two population types, large deep colonies and shallow small colonies.
Large drop off in shallow water at age 4, due to sponges and collection.
Genetic distance becomes significant at 100s of kms.
Thus, preservation of numerous populations needed.
Management on regional scale needed.
Must avoid local extinctions.
Conservation recommendations
Must be managed at national and international scales.
Only policy that works for such species.
Set minimum colony sizes, maximum yield per area, harvesting seasons.
Mumby et al. 2004
Reef fish often use mangroves as nurseries.
But can use other environments, not confined.
Also, despite deforestation, other pressures (fishing, larval supply) likely larger.
Management should include connected habitats, not islands of each type.
Future destruction of mangroves will have negative influence on reef.
Mumby et al. 2007
Caribbean reefs have damage from loss of Diadema antillarum and two species of coral.
“Sick” reefs characterized by macroalgae.
Can macroalgae be reversed? Or is it a stable state?
Used computer modeling and simulation.
Showed reefs can easily change to other states once D. antillarum died off.
With only parrotfish as grazers, small negative change in parrotfish numbers results in macroalgae blooms.
Coral becomes unstable state with low grazing.
Regular impact of hurricanes worsens with lack of grazers (fish and urchins).
Modeling useful for conservation targets.
Part 5 - Community conservation of coral reefs
History
Philippines consist of 7000+ islands.
Centuries have used reefs for livelihood.
Since 1970s, threatened by over-exploitation and destructive fishing methods.
Conservation started in 1974. Many projects failed.
Politics tied to conservation.
Local governments have authority but not knowledge or budget.
To be successful, combination of local and national people.
Within local group, must include users of reef; fishermen, resort owners, coastal residents, scuba divers.
Start of conservation
MDCP started in 1986 on three islands (62-166 households); Apo, Pamilacan, Balicasag.
All had less fish catch, increasing destruction and poverty.
MCDP plan
Marine reserves with buffer areas to increase number and diversity fish.
Development of local knowledge and alternative work.
Community center.
Outreach and replication program.
MCDP steps
Integration into community.
Education - marine ecology and resource management.
Group building, formalizing, strengthening.
Results
Apo & Pamilacan remain strong.
Balicasag protection groups somewhat weakened due to large PTA resort and less local “ownership”.
PTA has good points too.
All islands have stronger municipal laws now.
Results
Local fisherman believe sanctuary has helped.
Comparison of 1985-86 data with 1992 shows increases in fish, stable coral cover.
Conclusions
MPAs work on small islands by preventing destructive fishing and making locals understand value of conservation.
Small islands easier to implement plans.
Immediate benefits must be seen.
Baseline data necessary.
Local fishermen help with MPA location decisions.
Conclusions
Locals must understand how problem and answer related.
Management groups must have respected members.
Link with all potentially helpful groups.
All plans vulnerable to politics and outside groups.
Part 6 - Conclusions
Towards the future
In the future, more conservation plans will be implemented.
The gap between well protected areas and those not protected will widen.
Towards the future
Very few non-protected reefs will survive.
Thanks!
References cited:
1. West & Salm. 2003. Resistance and resilience to coral bleaching. Conservation Biol 17: 956-967.
2. Santangelo & Abbiati. 2001. Red coral: conservation and management of an over-exploited Mediterranean species. Aquatic Conserv Mar Freshwater Ecosys 11: 253-259.
3. Hughes et al. 2002. Biodiversity hotspots, centres of endemicity, and the conservation of coral reefs. Ecol Let 5: 775-784.
4. Roberts et al. 2002. Marine biodiversity hotspots and conservation priorities for tropical reefs. Science 295: 1280-1284. 8. 5. 5. Mumby et al. 2004. Mangroves enhance the biomass of coral reef fish communities in the Caribbean. Nature 427: 533-536. 9.
6. Mumby et al. 2007. Thresholds and the resilience of Caribbean coral reefs. Nature 450: 98-101.
7. White & Vogt. 2000. Philippine coral reefs under threat: lessons learned after 25 years of community-based reef conservation. Mar Poll Bull 40: 537-550.
January 5th class
Outline
• 1. Review of evolution.
• 2. Introduction to reticulate evolution.
• 3. Examples from plants and fish.
• 4. Examples from corals.
• 5. Examples from zoanthids.
• 6. Conclusions
Part 1 - Evolution
Genetic Diversity
• Required to adapt to change in environment.
• Many methods of measurement.
• Large populations of naturally breeding animals have high genetic diversity.
• Reduced populations are concern.
Cnidaria DNA
刺胞動物の遺伝子
mitochondrial DNA (mt DNA)
• evolves very slow in Cnidaria, opposite to most animals.
• 他の動物と違い、刺胞動物で進化が遅い。
DNA amd phylogenetics: All cells contain DNA - the code or blueprint of life.
全ての細胞には遺伝子が入っている。遺伝子は生き物の設計図。
This code has only four different “letters”: A, G, C, T.
遺伝子は４つのコードしかない。
Usual length 105 to 1010 base pairs.
生き物のひとつの細胞にある遺伝子の長さは105 to 1010 。
Genome projects read everything in one organism, but takes time and expensive.
全ての遺伝子を読むことは時間とお金の無駄。
Many studies use one or a few “markers” to investigate relations.
遺伝子の短い部分だけでも系統関係が解析できる。
• By collecting the same marker from different samples and then analyzing them, we can make a tree.
• いくつかのサンプルから同じマーカーを読んで、並べてから、解析し系統樹を作る。
• It is thought/hoped a tree is similar to how evolution occurred.
• 系統樹から進化が見えると思われる。
Part 2 -
Reticulate Evolution
What is evolution?
進化というのは？
• The descent of all organisms from a common ancestor.
• 全生物は共通の祖先から。
• The development of unique traits in response to environment, etc.
• 環境の変化などのせいで、それぞれのグループがユニークな特徴を持つ。
• Groups gradually “drift” away from each other.
• それぞれのグループが他のグループからだんだん離れる。
• But…
Some problems…
いくつかの問題点がある
• How can “mega”-diversity arise?
• 非常に高い多様性はどうやって進化した？
• Even allowing for rapid evolution, there are cases of “mega”-diversity in very new and small environments, with many species adapted to very specific niches (plants, cichlids etc.).
• 時として、新しい環境で、種の数が想像以上に多い。
• Often hard to accurately explain “species” over large geographic scales.
• large geographic scaleで、種の説明や分類が困難になる場合がある。
• How can hybridization between species be explained?
• 別種のhybridizationも説明がしにくい。
Theory of evolution over time
• Evolution is evolving.
• Darwin - classic model.
• Currently, reticulate evolution is a “rare nuisance”.
• Likely our ideas will develop into an even more complex model.
Reticulate evolution?
網状進化とは？
• The pattern of evolution resulting from recombinational speciation.
• 種類Aと種類Bのハイブリッドによる進化。
• Not generally expected to be a common occurrence, but can explain “mega-diversity” in new environments and unexpected genetic results.
• 普通の進化より珍しいが、新しい環境などでは起こる可能性がある。
• Results in retainment of ancestral patterns in the genome, with “repackaging”.
• 遺伝子の配列は進化（変異）しない。ただ新しい組み合わせができるだけ。
• Believed to occur in many plant groups, and cichlids (fish).
• 植物やアフリカの池の魚類で起こっていると思われている。
Evidence of reticulate evolution
網状進化の証拠
• Without laboratory experiments very hard to infer, but some ways:
• 研究室の実験以外で網状進化をどうやって見つける？
• Shared sequence portions between or within species.
• 種内、また種間の配列を見て、同じ部分があるかどうか？
• Differences between mitochondrial and nuclear DNA.
• ミトコンドリアDNAと核DNAの解析結果が違うかどうか？
Part 3 - Examples of Reticulate Evolution: Plants and Fishes
Example 1: peony flowers
(Sang et al. 1995)
• Sequenced ITS-rDNA of 33 species of Paeonia from Europe and Asia.
• Shrubs and herbs in northern hemisphere.
• Spotty distribution.
Results
• Examined ITS-1 sequences.
• Many species showed additive patterns.
• Subsequent evolution has taken place in some species.
• Many hybrid species Asian.
• Parents of these hybrid species European.
• Suggests hybridization occurred in past.
Conclusions
• Can see historical patterns, useful in species with no fossil history.
• This type of evolution may be common in plants.
• In such cases must be careful with phylogenetics.
Another example:
Cameroonian crater
lake cichlid fish
• Megadiverse group of fish with monophyletic origin.
• Much research shows reticulate evolution may occur when nuclear and mt DNA phylogenies do not match.
• Invasion of new environments could trigger hybridization between species.
Background
• Do hybrid swarms result from large areas with different environments or not?
• Cichlid fish provide great test case!
Barombi Mbo Lake
• 2.5 km in diameter.
• 110 m deep, only oxygen to 40 m.
• Four endemic genera; seven species.
• All on IUCN Red List - critically endangered.
• Evolved over 10000 years.
Materials and methods
• Two mt DNA markers and 2 nuclear markers.
• All types of fish from lake sampled; specimens deposited in museums.
Results
• Differences in mt DNA and nuclear DNA.
• Secondary hybridization after evolution.
• Two ancient lineages formed new species; Pungu madareni.
Conclusions
• Hybrid speciation can make complex species assemblages even without prior hybridization.
Part 4 - Examples of Reticulate Evolution: Corals
Reticulate Evolution in Cnidaria?
刺胞動物門は網状進化する？
• Several studies hint at reticulate evolution in Cnidaria, particularly corals and related groups.
• 特に花虫綱で網状進化の可能性がある。
• Marine environments where coral reefs are found are generally “new”.
• サンゴ礁の環境は比較的新しい。
• Centers of “mega-diversity” with “hyper-evolution” to micro-niches.
• 狭い地域で、多様性が非常に高い。
Acropora spp.
(Odorico & Miller 1997)
• Acropora very diverse, much morphological variation.
• Hybridization known from lab tests.
• ITS-rDNA shown to be a useful tool to detect this.
• Six colonies from five species.
• 18S rDNA and 28S rDNA obtained as well as ITS-rDNA.
Results
• Acropora ITS rDNA very short.
• Unexpected patterns of diversity, even within individuals!
• Such patterns consistent with ongoing reticulate evolution.
Conclusions
• Much more diversity than seen in plant ITS-rDNA.
• Could be due to more hybridization over longer ranges.
• Hybridization may occur over biological (not geological) time scales.
More corals
(Vollmer & Palumbi 2002)
• Examined all three Caribbean Acropora spp.
• Examined 2 nuclear and one mt DNA marker.
Results
• A. cervicornis and A. palmata distinct species.
• A. prolifera are F1 hybrids.
• Shape of A. prolifera depends on which species provided egg.
Conclusions
• F1 hybrids are immortal mules that may occasionally hybridize.
• Hybrids may be common in corals.
Part 5 -
Reticulate evolution in zoanthids
網状進化とスナギンチャク
Zoanthus spp. according to mt COI DNA
mt COIの結果による、マメスナギンチャク属の多様性
• Three species found with varying distribution. All ecologically similar to hard corals.
• ３つの種。生態はイシサンゴと似ている。
• Clear morphological variation between all three species.
• それぞれの種を区別できるようになった。
• This appears to be normal evolution.
• このデータから、普通の進化が推測できる。
核遺伝子(ITS-rDNA)配列結果
• All Z. kuroshio and Z. gigantus sequenced as expected.
• Z. kuroshio と Z. gigantusの結果はそれぞれが単系統。
• Z. sansibaricus had unusual results.
• 一方、 Z. sansibaricusの結果は単系統ではなかった！
• Some (2/3) samples gave expected sequences.
• 2/3のサンプルの配列（sansi）はmt DNAでの系統的位置と同様だったが、
• Some samples had both expected sequences and unknown “B” sequences.
• いくつかのZ. sansibaricus は不思議な “B”配列と普通の配列（sansi） 、両方を持つ。
• Some samples had only “B” sequences.
• 残りのZ. sansibaricus は不思議な “B”配列しか持っていない。
• B is closely related but different than Z. gigantus.
• “B”はZ. gigantus と近縁である。
Zoanthus undergoing reticulate evolution?
マメスナギンチャク属の網状進化？
• Samples with normal sequences and with normal/B, or just B have normal Z. sansibaricus morphology.
• 全てのZ. sansibaricusの形態が同じだった。
• Could B-only be F2 - resulting from backcrossing or F1 x F1 crossing?
• “B”配列しか持っていないサンプルはF2？
• Z. sansibaricus mass spawns, same as coral. No distribution barriers.
• マメスナギンチャク類はサンゴの様に同時に産卵する可能性がある。
• COI and morphology suggests NOT incomplete lineage sorting.
• 形態の結果やmt DNA配列を見ると、 incomplete lineage sortingじゃないと思うことができる。
Possible scenario for Zoanthus evolution
Zoanthus類の進化の説明
• Ancestor of Z.gigantus/B underwent one way hybridization (male B X female sansi), introducing B allele into Z. sansibaricus species.
• Z.gigantus/Bの精子（nuclear DNA）がZ. sansibaricus 種内に入ってきた。
• Modern-day Z. sansibaricus has both B and sansi alleles, ancestral B/giga evolved into modern Z. gigantus.
• 現在のZ. sansibaricusはsansiもBも持っている。
• 現在のZ. gigantusは昔のZ.gigantus/Bから進化した。
More zoanthids
(Reimer et al. 2007b)
• Investigated Palythoa spp. in Japan.
• Thought to be two genera, but mt DNA shows one genus.
• P. tuberculosa and P. mutuki very closely related.
Results
• ITS-rDNA shows two species (P. tuberculosa & P. mutuki) very closely related.
• Some specimens with intermediate morphology also apparently intermediate in phylogeny.
Results (2)
• Alignment of ITS-rDNA shows “reticulate” patterns between intermediates of two species.
• Appears as if some P. tuberculosa DNA has entered into P. mutuki population.
Conclusion 2
• In the future, more reticulate evolution will be found.
• This will impact conservation and our understanding of species.
Conclusion 3
• This will lead to better understanding of other related evolutionary events, such as lateral gene transfer (LGT).
References cited:
1. Sang et al. 1995. Documentation of reticulate evolution in peonies (Paeonia) using internal transcribed spacer sequences of nuclear ribosomal DNA: Implications for biogeography and concerted evolution. PNAS USA 92: 6813-6817.
2. Schliewen & Klee. 2005. Reticulate sympatric speciation in Cameroonian crater lake cichlids. Frontiers Zool 1:5.
3. Odorico & Miller. 1997. Variation in the ribosomal internal transcribed spacers and 5.8S rDNA among five species of Acropora (Cnidaria; Scleractinia): Patterns of variation consistent with reticulate evolution. Mol Biol Evol 14: 465-473.
4. Vollmer & Palumbi. 2002. Hybridization and the evolution of reef coral diversity. Science 296: 2023-2025.
5. Reimer et al. 2007a. Molecular evidence suggesting interspecific hybridization in Zoanthus spp. (Anthozoa: Hexacorallia). Zool Sci 24: 346-359.
6. Reimer et al. 2007b. Diversity and evolution in the zoanthid genus Palythoa (Cnidaria: Hexacorallia) based on nuclear ITS-rDNA. Coral Reefs 26: 399-410.
7. Shiroma and Reimer 2010. Zoological Studies.
• 1. Review of evolution.
• 2. Introduction to reticulate evolution.
• 3. Examples from plants and fish.
• 4. Examples from corals.
• 5. Examples from zoanthids.
• 6. Conclusions
Part 1 - Evolution
Genetic Diversity
• Required to adapt to change in environment.
• Many methods of measurement.
• Large populations of naturally breeding animals have high genetic diversity.
• Reduced populations are concern.
Cnidaria DNA
刺胞動物の遺伝子
mitochondrial DNA (mt DNA)
• evolves very slow in Cnidaria, opposite to most animals.
• 他の動物と違い、刺胞動物で進化が遅い。
DNA amd phylogenetics: All cells contain DNA - the code or blueprint of life.
全ての細胞には遺伝子が入っている。遺伝子は生き物の設計図。
This code has only four different “letters”: A, G, C, T.
遺伝子は４つのコードしかない。
Usual length 105 to 1010 base pairs.
生き物のひとつの細胞にある遺伝子の長さは105 to 1010 。
Genome projects read everything in one organism, but takes time and expensive.
全ての遺伝子を読むことは時間とお金の無駄。
Many studies use one or a few “markers” to investigate relations.
遺伝子の短い部分だけでも系統関係が解析できる。
• By collecting the same marker from different samples and then analyzing them, we can make a tree.
• いくつかのサンプルから同じマーカーを読んで、並べてから、解析し系統樹を作る。
• It is thought/hoped a tree is similar to how evolution occurred.
• 系統樹から進化が見えると思われる。
Part 2 -
Reticulate Evolution
What is evolution?
進化というのは？
• The descent of all organisms from a common ancestor.
• 全生物は共通の祖先から。
• The development of unique traits in response to environment, etc.
• 環境の変化などのせいで、それぞれのグループがユニークな特徴を持つ。
• Groups gradually “drift” away from each other.
• それぞれのグループが他のグループからだんだん離れる。
• But…
Some problems…
いくつかの問題点がある
• How can “mega”-diversity arise?
• 非常に高い多様性はどうやって進化した？
• Even allowing for rapid evolution, there are cases of “mega”-diversity in very new and small environments, with many species adapted to very specific niches (plants, cichlids etc.).
• 時として、新しい環境で、種の数が想像以上に多い。
• Often hard to accurately explain “species” over large geographic scales.
• large geographic scaleで、種の説明や分類が困難になる場合がある。
• How can hybridization between species be explained?
• 別種のhybridizationも説明がしにくい。
Theory of evolution over time
• Evolution is evolving.
• Darwin - classic model.
• Currently, reticulate evolution is a “rare nuisance”.
• Likely our ideas will develop into an even more complex model.
Reticulate evolution?
網状進化とは？
• The pattern of evolution resulting from recombinational speciation.
• 種類Aと種類Bのハイブリッドによる進化。
• Not generally expected to be a common occurrence, but can explain “mega-diversity” in new environments and unexpected genetic results.
• 普通の進化より珍しいが、新しい環境などでは起こる可能性がある。
• Results in retainment of ancestral patterns in the genome, with “repackaging”.
• 遺伝子の配列は進化（変異）しない。ただ新しい組み合わせができるだけ。
• Believed to occur in many plant groups, and cichlids (fish).
• 植物やアフリカの池の魚類で起こっていると思われている。
Evidence of reticulate evolution
網状進化の証拠
• Without laboratory experiments very hard to infer, but some ways:
• 研究室の実験以外で網状進化をどうやって見つける？
• Shared sequence portions between or within species.
• 種内、また種間の配列を見て、同じ部分があるかどうか？
• Differences between mitochondrial and nuclear DNA.
• ミトコンドリアDNAと核DNAの解析結果が違うかどうか？
Part 3 - Examples of Reticulate Evolution: Plants and Fishes
Example 1: peony flowers
(Sang et al. 1995)
• Sequenced ITS-rDNA of 33 species of Paeonia from Europe and Asia.
• Shrubs and herbs in northern hemisphere.
• Spotty distribution.
Results
• Examined ITS-1 sequences.
• Many species showed additive patterns.
• Subsequent evolution has taken place in some species.
• Many hybrid species Asian.
• Parents of these hybrid species European.
• Suggests hybridization occurred in past.
Conclusions
• Can see historical patterns, useful in species with no fossil history.
• This type of evolution may be common in plants.
• In such cases must be careful with phylogenetics.
Another example:
Cameroonian crater
lake cichlid fish
• Megadiverse group of fish with monophyletic origin.
• Much research shows reticulate evolution may occur when nuclear and mt DNA phylogenies do not match.
• Invasion of new environments could trigger hybridization between species.
Background
• Do hybrid swarms result from large areas with different environments or not?
• Cichlid fish provide great test case!
Barombi Mbo Lake
• 2.5 km in diameter.
• 110 m deep, only oxygen to 40 m.
• Four endemic genera; seven species.
• All on IUCN Red List - critically endangered.
• Evolved over 10000 years.
Materials and methods
• Two mt DNA markers and 2 nuclear markers.
• All types of fish from lake sampled; specimens deposited in museums.
Results
• Differences in mt DNA and nuclear DNA.
• Secondary hybridization after evolution.
• Two ancient lineages formed new species; Pungu madareni.
Conclusions
• Hybrid speciation can make complex species assemblages even without prior hybridization.
Part 4 - Examples of Reticulate Evolution: Corals
Reticulate Evolution in Cnidaria?
刺胞動物門は網状進化する？
• Several studies hint at reticulate evolution in Cnidaria, particularly corals and related groups.
• 特に花虫綱で網状進化の可能性がある。
• Marine environments where coral reefs are found are generally “new”.
• サンゴ礁の環境は比較的新しい。
• Centers of “mega-diversity” with “hyper-evolution” to micro-niches.
• 狭い地域で、多様性が非常に高い。
Acropora spp.
(Odorico & Miller 1997)
• Acropora very diverse, much morphological variation.
• Hybridization known from lab tests.
• ITS-rDNA shown to be a useful tool to detect this.
• Six colonies from five species.
• 18S rDNA and 28S rDNA obtained as well as ITS-rDNA.
Results
• Acropora ITS rDNA very short.
• Unexpected patterns of diversity, even within individuals!
• Such patterns consistent with ongoing reticulate evolution.
Conclusions
• Much more diversity than seen in plant ITS-rDNA.
• Could be due to more hybridization over longer ranges.
• Hybridization may occur over biological (not geological) time scales.
More corals
(Vollmer & Palumbi 2002)
• Examined all three Caribbean Acropora spp.
• Examined 2 nuclear and one mt DNA marker.
Results
• A. cervicornis and A. palmata distinct species.
• A. prolifera are F1 hybrids.
• Shape of A. prolifera depends on which species provided egg.
Conclusions
• F1 hybrids are immortal mules that may occasionally hybridize.
• Hybrids may be common in corals.
Part 5 -
Reticulate evolution in zoanthids
網状進化とスナギンチャク
Zoanthus spp. according to mt COI DNA
mt COIの結果による、マメスナギンチャク属の多様性
• Three species found with varying distribution. All ecologically similar to hard corals.
• ３つの種。生態はイシサンゴと似ている。
• Clear morphological variation between all three species.
• それぞれの種を区別できるようになった。
• This appears to be normal evolution.
• このデータから、普通の進化が推測できる。
核遺伝子(ITS-rDNA)配列結果
• All Z. kuroshio and Z. gigantus sequenced as expected.
• Z. kuroshio と Z. gigantusの結果はそれぞれが単系統。
• Z. sansibaricus had unusual results.
• 一方、 Z. sansibaricusの結果は単系統ではなかった！
• Some (2/3) samples gave expected sequences.
• 2/3のサンプルの配列（sansi）はmt DNAでの系統的位置と同様だったが、
• Some samples had both expected sequences and unknown “B” sequences.
• いくつかのZ. sansibaricus は不思議な “B”配列と普通の配列（sansi） 、両方を持つ。
• Some samples had only “B” sequences.
• 残りのZ. sansibaricus は不思議な “B”配列しか持っていない。
• B is closely related but different than Z. gigantus.
• “B”はZ. gigantus と近縁である。
Zoanthus undergoing reticulate evolution?
マメスナギンチャク属の網状進化？
• Samples with normal sequences and with normal/B, or just B have normal Z. sansibaricus morphology.
• 全てのZ. sansibaricusの形態が同じだった。
• Could B-only be F2 - resulting from backcrossing or F1 x F1 crossing?
• “B”配列しか持っていないサンプルはF2？
• Z. sansibaricus mass spawns, same as coral. No distribution barriers.
• マメスナギンチャク類はサンゴの様に同時に産卵する可能性がある。
• COI and morphology suggests NOT incomplete lineage sorting.
• 形態の結果やmt DNA配列を見ると、 incomplete lineage sortingじゃないと思うことができる。
Possible scenario for Zoanthus evolution
Zoanthus類の進化の説明
• Ancestor of Z.gigantus/B underwent one way hybridization (male B X female sansi), introducing B allele into Z. sansibaricus species.
• Z.gigantus/Bの精子（nuclear DNA）がZ. sansibaricus 種内に入ってきた。
• Modern-day Z. sansibaricus has both B and sansi alleles, ancestral B/giga evolved into modern Z. gigantus.
• 現在のZ. sansibaricusはsansiもBも持っている。
• 現在のZ. gigantusは昔のZ.gigantus/Bから進化した。
More zoanthids
(Reimer et al. 2007b)
• Investigated Palythoa spp. in Japan.
• Thought to be two genera, but mt DNA shows one genus.
• P. tuberculosa and P. mutuki very closely related.
Results
• ITS-rDNA shows two species (P. tuberculosa & P. mutuki) very closely related.
• Some specimens with intermediate morphology also apparently intermediate in phylogeny.
Results (2)
• Alignment of ITS-rDNA shows “reticulate” patterns between intermediates of two species.
• Appears as if some P. tuberculosa DNA has entered into P. mutuki population.
Conclusion 2
• In the future, more reticulate evolution will be found.
• This will impact conservation and our understanding of species.
Conclusion 3
• This will lead to better understanding of other related evolutionary events, such as lateral gene transfer (LGT).
References cited:
1. Sang et al. 1995. Documentation of reticulate evolution in peonies (Paeonia) using internal transcribed spacer sequences of nuclear ribosomal DNA: Implications for biogeography and concerted evolution. PNAS USA 92: 6813-6817.
2. Schliewen & Klee. 2005. Reticulate sympatric speciation in Cameroonian crater lake cichlids. Frontiers Zool 1:5.
3. Odorico & Miller. 1997. Variation in the ribosomal internal transcribed spacers and 5.8S rDNA among five species of Acropora (Cnidaria; Scleractinia): Patterns of variation consistent with reticulate evolution. Mol Biol Evol 14: 465-473.
4. Vollmer & Palumbi. 2002. Hybridization and the evolution of reef coral diversity. Science 296: 2023-2025.
5. Reimer et al. 2007a. Molecular evidence suggesting interspecific hybridization in Zoanthus spp. (Anthozoa: Hexacorallia). Zool Sci 24: 346-359.
6. Reimer et al. 2007b. Diversity and evolution in the zoanthid genus Palythoa (Cnidaria: Hexacorallia) based on nuclear ITS-rDNA. Coral Reefs 26: 399-410.
7. Shiroma and Reimer 2010. Zoological Studies.
December 22nd class
Outline
• 1. Quick introduction to diseases.
• 2. Common coral reef diseases.
• 3. Why are diseases becoming common?
• 4. How do diseases affect conservation?
5. Terpios: a new threat
• 6. Conclusions
Part 1: Disease
Example 1: Plague in humans
• Plagues have struck humans many times.
• Often kill 10-50% of population.
• Caused by an influenza virus.
• Two most infamous cases are 13th century Black Plague, and 1919-1920 Spanish Influenza.
• No one knows where plagues came from.
• Spread through common routes of trade.
• Spread faster in modern cases.
• Often affects young adults worse due to “cytokine storms”.
Spanish Influenza
• In some countries fatalities were as high as 50%.
• Killed more people than WWI.
How does this happen?
• New mutation in influenza virus that most humans do not have capability to respond to.
• Genetic variation provides resistance.
• SARS is a more recent case.
Example 2:
Introduction of a new disease into an isolated area
Elm trees common in North America and Eurasia.
Preyed upon by two species of bark beetles.
Beginning in the 1910s, some elms began to die.
Die-offs became rapid in 1960s.
Bark beetles somehow involved in the disease.
Survival of elms close to 0%.
• The causative agents of DED are ascomycete microfungi.
• Carried by the elm bark beetles.
• Three species are now recognized: Ophiostoma ulmi, which afflicted Europe in 1910, reaching North America on imported timber in 1928, Ophiostoma himal-ulmi, a species endemic to the western Himalaya, and the extremely virulent species, Ophiostoma novo-ulmi, which was first described in Europe and North America in the 1940s and has devastated elms in both areas since the late 1960s.
• The origin of O. novo-ulmi remains unknown but may have arisen as a hybrid between O. ulmi and O. himal-ulmi.
Part 2: Common coral reef diseases
Introduction to
coral reef diseases
• Bacteria observed in corals in early 1900s.
• Diseases noticed in 1970s, seemingly increasing over last 30 years.
• 34 mass events, affecting sponges, seagrasses, cetaceans, urchins, fish, molluscs, corals.
• Have changed composition of reefs.
Diseases affecting Scleractinia
• Many diseases named, but very little known.
• Most pathogens still unknown.
• Most common in Atlantic (Green & Bruckner).
• Not to be confused with coral bleaching.
Green & Bruckner 2000
Black Band Disease (BBD) Caused by numerous cyanobacteria (500 spp.) as a microbial mat.
Mat makes the colored band.
First observed in 1973.
Moves 3mm to 1cm/day.
Found in 42 spp. of coral.
Kuta & Richardson 2002
• BBD correlates strongly with depth, temperature, nitrites.
• Also correlates with diversity and orthophosphate.
White band disease: Pathogen unknown, may be bacteria. Noticed in 1981.
Tissue loss from base to tip.
Affects two species, Acropora cervicornis and A. palmata.
Moves 3mm to 1cm/day.
• WBD has drastically altered Caribbean reefs.
• Shifts in coral species.
• Loss of overall coral cover; algae increasing.
• Both species now “threatened”.
• Losses of over 98% of A. cervicornis. Locally extinct.
White plague: Affects many species, but no acroporoids.
Caused by Aurantimonas bacteria.
First observed in 1977.
Aspergillosis: Caused by terrestrial fungi.
Affect mainly Atlantic gorgonians.
Also affects waterfowl.
Noted in 1997.
Tumors: Similar to cancer.
Affects mainly A. palmata.
Irregular growth, no zooxanthellae.
Noted in 1960s and 1970s.
Other diseases: Many other diseases.
Mostly known from Atlantic.
Yellow band disease, yellow spot disease, white pox disease, brown band disease.
Most noted for first time in last 20 years.
Pathogens usually unknown.
Part 3: Why are diseases becoming common?
1. Global warming?
• Many people blame global warming.
• But likely much more complex.
2. Nutrient enrichment - Bruno et al. 2003
• Experiments done with YBD and Aspergillosis.
• Controls were disease only, experimental with added nitrogen and phosphorus.
Results - Aspergillosis
• Nutrients increased severity of disease in sea fans.
Results - YBD
• Presence of nutrients increased rate at which YBD developed in two species of coral.
3. Dust? -
Garrison et al. 2003
• Airborne dust from Africa and Asia carries many contaminants to reefs.
• Global warming and desertification increasing dust, therefore increasing contaminants.
Part 4: How do diseases affect conservation?
Effects are widespread
Many studies have documented widespread coral decline in almost ALL coral species.
Porter et al. 2001 showed many declines 1996-1998 NOT due to coral bleaching but disease.
• Porter et al. 2001 cont
• Green & Bruckner 2000
• Green & Bruckner 2000
Many examples of diseases spreading, many examples of reef degradation (show many photos).
Overview of disease
• All diseases have negative effects.
• Only WBD has changed communities drastically.
• Pacific 15 years behind Atlantic.
• Compounded negative influences more severe for coral reefs.
Part 5: Preliminary results of field surveys of Terpios outbreaks in the Nansei Islands, Japan
Terpios hoshinota Rützler and Muzik 1993
Terpios in the Nansei Islands - history
Outbreak noticed in Mariana Is. 1973. (Bryan 1973 )
Terpios-Nansei project
Assess the current distribution of Terpios in the Nansei Islands.
Establish monitoring sites.
If present, characterize sexual reproduction & ecology.
Methods
Survey all major islands by snorkel/scuba (Reimer).
Monthly/bi-monthly sampling at designated locations – histology (Hirose), genetics (Chen).
Permanent transects at massive outbreak (Reimer), analyses (Reimer, Nozawa).
Preliminary results
Three situations observed: none, small amounts, massive outbreak
Disappearance?
Yonama, Tokunoshima had massive outbreak (87.9% cover) in 1986 (Marine Park Center Foundation 1986).
Discussion
Terpios absent or present in small numbers in most reefs in Nansei Islands (38/39 examined locations).
Coverage does not appear to fluctuate much in most locations.
Discussion & Questions
Massive outbreaks still occur in Nansei Islands.
How long do outbreaks last?
“Recovery” observed at Yonama, but is this true recovery? At least, not a dead-end.
Results suggest outbreaks are linked to reef degradation, but factors not clear.
Future work
Permanent transect results & analyses.
Try to quantify speed at which massive outbreaks can occur.
Combine analyses with genetic, histological results.
Examine Yakomo (current outbreak location) to understand causes of outbreaks. Why this location?
Part 6: Conclusions.
Conclusion 1
• Disease more widespread on reefs in Caribbean.
• More research? Partially.
• Monitoring in Pacific very critical.
Conclusion 2
• Only one disease has permanently changed community structure (WBD).
• Other diseases locally important.
Conclusion 3
• Very few studies have investigated in detail mortality rates.
• Monitoring of individual colonies needed.
Conclusion 4
• Diseases increasing.
• Bleaching appears to be more critical, but two problems appear related.
Conclusion 5
• Diseases not well understood.
• Many diseases affect many species; possibly more or less diseases.
• Pathogens need to be investigated.
Conclusion 6
• While bleaching currently more serious, foolish to ignore diseases.
• May be “indicator” of serious problems, similar to amphibians.
What needs to be done
• <3% of reefs in danger have low human impact.
• More research needed on human influences and pathogens.
• Management and conservation then follow.
References:
1. Green & Bruckner. 2000. The significance of coral disease epizootiology for coral reef conservation. Biological Conservation 96: 347-361.
2. Aronson & Precht. 2001. White-band disease and the changing face of Caribbean coral reefs. Hydrobiologia 460: 25-38.
3. Garrison et al. 2003. African and Asian dust: from desert soils to coral reefs. BioScience 53: 469-481.
4. Bruno et al. 2003. Nutrient enrichment can increase the severity of coral diseases. Ecology Letters 6: 1056-1061.
5. Kuta & Richardson. 2002. Ecological aspects of black band disease of corals: relationships between disease incidence and environmental factors. Coral Reefs 21: 393-398.
6. Porter et al. 2001. Patterns of spread of disease in the Florida Keys. Hydrobiologia 460: 1-24.
7. Reimer, Hirose, et al. new Terpios papers.
• 1. Quick introduction to diseases.
• 2. Common coral reef diseases.
• 3. Why are diseases becoming common?
• 4. How do diseases affect conservation?
5. Terpios: a new threat
• 6. Conclusions
Part 1: Disease
Example 1: Plague in humans
• Plagues have struck humans many times.
• Often kill 10-50% of population.
• Caused by an influenza virus.
• Two most infamous cases are 13th century Black Plague, and 1919-1920 Spanish Influenza.
• No one knows where plagues came from.
• Spread through common routes of trade.
• Spread faster in modern cases.
• Often affects young adults worse due to “cytokine storms”.
Spanish Influenza
• In some countries fatalities were as high as 50%.
• Killed more people than WWI.
How does this happen?
• New mutation in influenza virus that most humans do not have capability to respond to.
• Genetic variation provides resistance.
• SARS is a more recent case.
Example 2:
Introduction of a new disease into an isolated area
Elm trees common in North America and Eurasia.
Preyed upon by two species of bark beetles.
Beginning in the 1910s, some elms began to die.
Die-offs became rapid in 1960s.
Bark beetles somehow involved in the disease.
Survival of elms close to 0%.
• The causative agents of DED are ascomycete microfungi.
• Carried by the elm bark beetles.
• Three species are now recognized: Ophiostoma ulmi, which afflicted Europe in 1910, reaching North America on imported timber in 1928, Ophiostoma himal-ulmi, a species endemic to the western Himalaya, and the extremely virulent species, Ophiostoma novo-ulmi, which was first described in Europe and North America in the 1940s and has devastated elms in both areas since the late 1960s.
• The origin of O. novo-ulmi remains unknown but may have arisen as a hybrid between O. ulmi and O. himal-ulmi.
Part 2: Common coral reef diseases
Introduction to
coral reef diseases
• Bacteria observed in corals in early 1900s.
• Diseases noticed in 1970s, seemingly increasing over last 30 years.
• 34 mass events, affecting sponges, seagrasses, cetaceans, urchins, fish, molluscs, corals.
• Have changed composition of reefs.
Diseases affecting Scleractinia
• Many diseases named, but very little known.
• Most pathogens still unknown.
• Most common in Atlantic (Green & Bruckner).
• Not to be confused with coral bleaching.
Green & Bruckner 2000
Black Band Disease (BBD) Caused by numerous cyanobacteria (500 spp.) as a microbial mat.
Mat makes the colored band.
First observed in 1973.
Moves 3mm to 1cm/day.
Found in 42 spp. of coral.
Kuta & Richardson 2002
• BBD correlates strongly with depth, temperature, nitrites.
• Also correlates with diversity and orthophosphate.
White band disease: Pathogen unknown, may be bacteria. Noticed in 1981.
Tissue loss from base to tip.
Affects two species, Acropora cervicornis and A. palmata.
Moves 3mm to 1cm/day.
• WBD has drastically altered Caribbean reefs.
• Shifts in coral species.
• Loss of overall coral cover; algae increasing.
• Both species now “threatened”.
• Losses of over 98% of A. cervicornis. Locally extinct.
White plague: Affects many species, but no acroporoids.
Caused by Aurantimonas bacteria.
First observed in 1977.
Aspergillosis: Caused by terrestrial fungi.
Affect mainly Atlantic gorgonians.
Also affects waterfowl.
Noted in 1997.
Tumors: Similar to cancer.
Affects mainly A. palmata.
Irregular growth, no zooxanthellae.
Noted in 1960s and 1970s.
Other diseases: Many other diseases.
Mostly known from Atlantic.
Yellow band disease, yellow spot disease, white pox disease, brown band disease.
Most noted for first time in last 20 years.
Pathogens usually unknown.
Part 3: Why are diseases becoming common?
1. Global warming?
• Many people blame global warming.
• But likely much more complex.
2. Nutrient enrichment - Bruno et al. 2003
• Experiments done with YBD and Aspergillosis.
• Controls were disease only, experimental with added nitrogen and phosphorus.
Results - Aspergillosis
• Nutrients increased severity of disease in sea fans.
Results - YBD
• Presence of nutrients increased rate at which YBD developed in two species of coral.
3. Dust? -
Garrison et al. 2003
• Airborne dust from Africa and Asia carries many contaminants to reefs.
• Global warming and desertification increasing dust, therefore increasing contaminants.
Part 4: How do diseases affect conservation?
Effects are widespread
Many studies have documented widespread coral decline in almost ALL coral species.
Porter et al. 2001 showed many declines 1996-1998 NOT due to coral bleaching but disease.
• Porter et al. 2001 cont
• Green & Bruckner 2000
• Green & Bruckner 2000
Many examples of diseases spreading, many examples of reef degradation (show many photos).
Overview of disease
• All diseases have negative effects.
• Only WBD has changed communities drastically.
• Pacific 15 years behind Atlantic.
• Compounded negative influences more severe for coral reefs.
Part 5: Preliminary results of field surveys of Terpios outbreaks in the Nansei Islands, Japan
Terpios hoshinota Rützler and Muzik 1993
Terpios in the Nansei Islands - history
Outbreak noticed in Mariana Is. 1973. (Bryan 1973 )
Terpios-Nansei project
Assess the current distribution of Terpios in the Nansei Islands.
Establish monitoring sites.
If present, characterize sexual reproduction & ecology.
Methods
Survey all major islands by snorkel/scuba (Reimer).
Monthly/bi-monthly sampling at designated locations – histology (Hirose), genetics (Chen).
Permanent transects at massive outbreak (Reimer), analyses (Reimer, Nozawa).
Preliminary results
Three situations observed: none, small amounts, massive outbreak
Disappearance?
Yonama, Tokunoshima had massive outbreak (87.9% cover) in 1986 (Marine Park Center Foundation 1986).
Discussion
Terpios absent or present in small numbers in most reefs in Nansei Islands (38/39 examined locations).
Coverage does not appear to fluctuate much in most locations.
Discussion & Questions
Massive outbreaks still occur in Nansei Islands.
How long do outbreaks last?
“Recovery” observed at Yonama, but is this true recovery? At least, not a dead-end.
Results suggest outbreaks are linked to reef degradation, but factors not clear.
Future work
Permanent transect results & analyses.
Try to quantify speed at which massive outbreaks can occur.
Combine analyses with genetic, histological results.
Examine Yakomo (current outbreak location) to understand causes of outbreaks. Why this location?
Part 6: Conclusions.
Conclusion 1
• Disease more widespread on reefs in Caribbean.
• More research? Partially.
• Monitoring in Pacific very critical.
Conclusion 2
• Only one disease has permanently changed community structure (WBD).
• Other diseases locally important.
Conclusion 3
• Very few studies have investigated in detail mortality rates.
• Monitoring of individual colonies needed.
Conclusion 4
• Diseases increasing.
• Bleaching appears to be more critical, but two problems appear related.
Conclusion 5
• Diseases not well understood.
• Many diseases affect many species; possibly more or less diseases.
• Pathogens need to be investigated.
Conclusion 6
• While bleaching currently more serious, foolish to ignore diseases.
• May be “indicator” of serious problems, similar to amphibians.
What needs to be done
• <3% of reefs in danger have low human impact.
• More research needed on human influences and pathogens.
• Management and conservation then follow.
References:
1. Green & Bruckner. 2000. The significance of coral disease epizootiology for coral reef conservation. Biological Conservation 96: 347-361.
2. Aronson & Precht. 2001. White-band disease and the changing face of Caribbean coral reefs. Hydrobiologia 460: 25-38.
3. Garrison et al. 2003. African and Asian dust: from desert soils to coral reefs. BioScience 53: 469-481.
4. Bruno et al. 2003. Nutrient enrichment can increase the severity of coral diseases. Ecology Letters 6: 1056-1061.
5. Kuta & Richardson. 2002. Ecological aspects of black band disease of corals: relationships between disease incidence and environmental factors. Coral Reefs 21: 393-398.
6. Porter et al. 2001. Patterns of spread of disease in the Florida Keys. Hydrobiologia 460: 1-24.
7. Reimer, Hirose, et al. new Terpios papers.
December 8th class
NOTICE: Please attend next week; we assign the reports on this day!
Today`s class: Outline
• 1. A new species of whale!
• 2. Atlantic and Pacific corals.
• 3. Four species of COTS.
• 4. Review of Symbiodinium and coral bleaching.
5. Diversity in Symbiodinium
Part 1 - A new species of whale!
Dalebout et al. 2002. A new species of beaked whale Mesoplodon perrini sp. n. (Cetacea: Ziphiidae) discovered through mitochondrial DNA sequences. Marine Mammal Science 18: 577-608.
Introduction
• Beaked whales are rare, with cryptic lifestyles. Most never observed alive.
• 12 species described in last 100 years!
• Mesoplodon hectori common in southeast Pacific.
Materials & Methods
• 5 specimens of beaked whale stranded in California, 1977-1995.
• Thought to be M. hectori based on morphology.
• Researchers then examined 2 mt DNA markers…
Results
• Results surprisingly show five specimens not M. hectori.
• New species!
• Re-examination shows morphological differences as well.
Discussion
• Authors suggest genetic voucher material for all taxa.
• Also state there are likely 40 marine mammal species still unknown!
• Cookiecutter sharks feed on M. perrini.
• Who knows what species await description?
Part 2 Atlantic & Pacific corals
Fukami et al. 2008. Mitochondrial and nuclear genes suggest that stony corals are monophyletic but most families of stony corals are not (Order Scleractinia, Class Anthozoa, Phylum Cnidaria). PLoS One 3:9: e3222
• Coral phylogeny has been in flux for 10+ years.
• Perhaps corallimorphs within hard corals.
• Here examine 127 species, 75 genera, 17 families.
• Four markers; 2 nuclear, 2 mitochondrial.
• Corals monophyletic.
• 11/16 families not monophyletic.
• Corresponding morphological characters found.
• Corallimorphs not part of stony corals.
• Many Atlantic corals are very unique, and should be conserved.
• Some clades vulnerable to extinction (II, V, VI, XV, XVIII+XX).
• Ability to conserve depends on knowing what to conserve.
• Re-organize based on DNA, re-examine morphology.
• Atlantic corals must be protected more strongly.
• Basic ideas need to be re-examined (e.g. favids).
Part 3 - Crown-of-thorns
Vogler et al. 2008. A threat to coral reefs multiplied? Four species of crown-of-thorns starfish. Biology Letters doi:1-.1098/rsbl.2008.0454
• Acanthaster planci outbreaks threaten coral reefs.
• Causes of outbreaks not clear.
• Species has long-lived larvae, but apparent population structure.
• Here used COI sequences from 237 samples.
• Four clades found, 8.8-10.6% divergent.
• Diverged 1.95-3.65 mya.
• Species show geographical partitioning. Due to sea level changes.
• All populations expanding.
• Four species, SIO, NIO, Red Sea, and Pacific.
• Outbreaks mainly seen in Pacific - could this be a species difference?
• Clearly more research needed, critical for coral reef management.
Overall conclusions:
1. Genetics already impacting our understanding of diversity.
2. Expect more surprises in the future.
3. Massive revision of all coral reef organisms!
Part 4 Review of Symbiodinium and bleaching.
• Dangers facing coral reefs:
• Global warming is raising the temperature of the ocean; this kills corals - “coral bleaching”.
• Also, as the oceans become more acidic, it is more difficult for corals to make their skeletons.
• Perhaps 90% of coral reefs will be dead by 2050.
• Diagram of iving tissue
• Numbers of zooxanthellate genera over time, increase in ZX genera of corals.
• More diverse than ever, showing benefits of symbioses.
• Believed to have started approximately 60 million years ago.
• Symbiodinium spp. in invertebrates holobiont=host+symbiont(s)
• Corals and symbionts
• Many shallow water corals get their energy from symbiotic zooxanthellae.
• These small animals make it possible for corals to live in the warm oceans.
• But, these symbionts are sensitive to hot ocean temperatures.
• What turns the coral white?
• As a stress response, corals expel the symbiotic zooxanthellae from their tissues
• The coral tissue is clear, so you see the white limestone skeleton underneath
• What can stress a coral?
• High light or UV levels
• Cold temperatures
• Low salinity and high turbidity from coastal runoff events or heavy rain
• Exposure to air during very low tides
• Major: high water temperatures
• Thermal stress
• Corals live close to their thermal maximum limit
• If water temperature gets 1 or 2°C higher than the summer average in many parts of the world, corals may get stressed and bleach
• NOAA satellites measure global ocean temperature and thermal stress
• How warm is warm?
• How hot do you think the ocean has to get before corals start to bleach?
• GLOBAL WARMING
• Glaciers and Sea Ice are melting
• World map showing levels of coral bleaching. Source: ReefBase
• Can corals recover?
• Yes, if the stress doesn’t last too long
• Some corals can eat more zooplankton to help survive the lack of zooxanthellae
• Some species are more resistant to bleaching, and more able to recover
• Can corals recover?
• Corals may eventually regain color by repopulating their zooxanthellae
• Algae may come from the water column
• Or they may come from reproduction of the few cells that remain in the coral
• Can corals recover?
• Corals can begin to recover after a few weeks
• Does bleaching kill corals?
• Yes, if the stress is severe
• Some of the polyps in a colony might die
• If the bleaching is really severe, whole colonies might die
• Bleaching in Puerto Rico killed an 800-year-old star coral colony in 2005
• What else can stress do to corals?
• Question: what is something that happens to people when they are highly stressed?
• What else can stress do to corals?
• Question: what is something that happens to people when they are highly stressed?
• Bleaching and coral disease
• Coral diseases are found around the world
• High temperatures and bleaching can leave corals more vulnerable to disease
• Can quickly kill part or all of the coral colony
• Bleaching and bioerosion
• We have seen that bleaching can kill part or all of a coral colony
• Areas of dead coral are more vulnerable to bioerosion (when animals wear away the coral reef’s limestone structure)
• Storms & coral bleaching
• The same warm water that causes corals to bleach can also lead to strong storms.
• Storms: a mixed blessing
• Storms: a mixed blessing
• Each passing hurricane in 2005 cooled the water in the Florida Keys.
References:
1. Dalebout et al. 2002. A new species of beaked whale Mesoplodon perrini sp. n. (Cetacea: Ziphiidae) discovered through phylogenetic analyses of mitochondrial DNA sequences. Marine Mammal Science 18: 577-608.
2. Fukami et al. 2008. Mitochondrial and nuclear genes suggest that stony corals are monophyletic but most families of stony corals are not (Order Scleractinia, Class Anthozoa, Phylum Cnidaria). PLoS One 3:9: e3222.
3. Vogler et al. 2008. A threat to coral reefs multiplied? Four species of crown-of-thorns starfish. Biology Letters doi:1-.1098/rsbl.2008.0454
Part 5: Investigating diversity of Symbiodinium: past to present.
What are zooxanthellae?
Algae that live in the coral polyp’s surface layer
Algae get nutrients and a safe place to grow
Corals get oxygen and help with waste removal
Corals also get most of their food from the algae
Symbiosis overview
Genus Symbiodinium
Described in 1962 by H. Freudenthal.
Within dinoflagellates.
Was though there was one single species worldwide.
Morphology & life cycle
Host species
Cnidaria (corals, jellyfish, anemone, zoanthids, octocorals).
Mollusca (clams, snails).
Platyhelminthes (flatworms).
Porifera (sponges).
Protista (forams).
First genetic studies
Rowan & Powers 1991.
Utlized 18S ribosomal DNA.
Sampled from corals & anemones.
Found unexpected diversity!
Recommended further genetic studies.
Second wave of studies
Used faster evolving DNA markers.
Particularly ITS-rDNA.
Even more diversity!
Zooxanthellae clade
DNA analyses
Clade: A group composed of all the species descended from a single common ancestor
Diversity
Eight major clades known.
Within each clade many subclades.
Do not know what taxonomic level clades are equal to.
Evolution and biogeography
Many studies have catalogued diversity.
Can now understand on many scales.
Can predict evolution.
Specific types
Many subclades or types associate with similar hosts.
Could be co-evolution.
Symbiodinium in Zoanthus sansibaricus
We sampled the same species from 4 locations.
Each host colony was shown to associate with one subclade of Symbiodinium.
Subclade C1/C3 was common in the north, and subclade A1 was dominant in the south.
C1/C3 has been shown to be a dominant Indo-Pacific “generalist”, with C15 common in Porites spp., and A1 a shallow-water specialist.
Modes of transmission & flexibility
2 major types; a) vertical and b) horizontal.
Vertical should result in more co-evolution and less flexibility.
Also, in horizontal, ZX from environment still rare.
Changes in ZX
over time?
Changes have been seen over time in content of ZX within coral colonies!
Particularly after bleaching events.
ZX shuffling?
Adaptive Bleaching Hypothesis (ABH).
Very controversial, large conservation implications.
Two ways this occurs.
Diversity within colonies
Same colony may have different ZX at different locations!
Differences in types
Since we know diversity, we can experiment with different conditions.
Many ZX are easy to culture.
Control light, temperature, nutrients, etc.
Can also then experiment in situ.
Symbiodinium spp. characters
Believed to alternate between a free-living stage with flagella, and a non-motile stage with chlorophyll.
Believed to sexually reproduce, although this has not been observed.
Overall morphological condition can degrade based on non-optimal environmental conditions, in particular low (<15 º C) and high (>30ºC) sustained ocean temperatures.
“Adaptive bleaching” hypothesis
Bleaching may enable corals to adopt different classes of zooxanthellae, better suited for a new environment. By:
‘symbiont switching’ (a new clade from exogenous sources) or
‘symbiont shuffling’ (host contains multiple clades and a shift in dominance occurs).
Can we protect corals from bleaching?
Marine invertebrate - Symbiodinium spp. symbioses overview
Symbiodinium spp. found in many clonal cnidarians (and other invertebrates) in tropical and sub-tropical oceans. Symbiodinium are the main reason coral reefs exist and have large levels of diversity.
Symbiodinium is now divided into 8 “clades” labelled A-H (of unknown taxonomic level) with many “subclades” (designated by numbers) within each clade (see various works by Pochon et al., and LaJeunesse et al.)
Host species’ association with various clades and subclades of Symbiodinium (often more than one) may be at least partially responsible for differences in bleaching patterns seen during bleaching events (i.e. ENSO event of 2001, etc.).
Also, some host species have been shown to have flexible associations with Symbiodinium over biogeographical ranges (depth, latitude, etc.) or time (summer versus winter, etc.). This is part of the Adaptive Bleaching Hypothesis (ABH) (Buddemier and Fautin 2004; Baker 2001), and is very contentious.
Need to understand Symbiodinium diversity within zoanthids before any discussion of symbiotic zoanthid ecology can be conducted.
References:
1. Rowan & Powers. 1991. Molecular genetic identification of symbiotic dinoflagellates (zooxanthellae). Marine Ecology Progress Series 71: 65-73.
2. Stat et al. 2006. The evolutionary history of Symbiodinium and scleractinian hosts - Symbiosis, diversity, and the effect of climate change. Plant Ecology, Evolution and Systematics 8: 23-43.
3. LaJeunesse 2005. ‘Species’ radiations of symbiotic dinoflagellates in the Atlantic and Indo-Pacific since the Miocene-Pliocene transition. Molecular Biology and Evolution 22: 570-581.
4. Pochon et al. 2004. Biogeographic partitioning and host specialization among foramineferan dinoflagellate symbionts (Symbiodinium; Dinophyta). Marine Biology 139: 17-27.
Today`s class: Outline
• 1. A new species of whale!
• 2. Atlantic and Pacific corals.
• 3. Four species of COTS.
• 4. Review of Symbiodinium and coral bleaching.
5. Diversity in Symbiodinium
Part 1 - A new species of whale!
Dalebout et al. 2002. A new species of beaked whale Mesoplodon perrini sp. n. (Cetacea: Ziphiidae) discovered through mitochondrial DNA sequences. Marine Mammal Science 18: 577-608.
Introduction
• Beaked whales are rare, with cryptic lifestyles. Most never observed alive.
• 12 species described in last 100 years!
• Mesoplodon hectori common in southeast Pacific.
Materials & Methods
• 5 specimens of beaked whale stranded in California, 1977-1995.
• Thought to be M. hectori based on morphology.
• Researchers then examined 2 mt DNA markers…
Results
• Results surprisingly show five specimens not M. hectori.
• New species!
• Re-examination shows morphological differences as well.
Discussion
• Authors suggest genetic voucher material for all taxa.
• Also state there are likely 40 marine mammal species still unknown!
• Cookiecutter sharks feed on M. perrini.
• Who knows what species await description?
Part 2 Atlantic & Pacific corals
Fukami et al. 2008. Mitochondrial and nuclear genes suggest that stony corals are monophyletic but most families of stony corals are not (Order Scleractinia, Class Anthozoa, Phylum Cnidaria). PLoS One 3:9: e3222
• Coral phylogeny has been in flux for 10+ years.
• Perhaps corallimorphs within hard corals.
• Here examine 127 species, 75 genera, 17 families.
• Four markers; 2 nuclear, 2 mitochondrial.
• Corals monophyletic.
• 11/16 families not monophyletic.
• Corresponding morphological characters found.
• Corallimorphs not part of stony corals.
• Many Atlantic corals are very unique, and should be conserved.
• Some clades vulnerable to extinction (II, V, VI, XV, XVIII+XX).
• Ability to conserve depends on knowing what to conserve.
• Re-organize based on DNA, re-examine morphology.
• Atlantic corals must be protected more strongly.
• Basic ideas need to be re-examined (e.g. favids).
Part 3 - Crown-of-thorns
Vogler et al. 2008. A threat to coral reefs multiplied? Four species of crown-of-thorns starfish. Biology Letters doi:1-.1098/rsbl.2008.0454
• Acanthaster planci outbreaks threaten coral reefs.
• Causes of outbreaks not clear.
• Species has long-lived larvae, but apparent population structure.
• Here used COI sequences from 237 samples.
• Four clades found, 8.8-10.6% divergent.
• Diverged 1.95-3.65 mya.
• Species show geographical partitioning. Due to sea level changes.
• All populations expanding.
• Four species, SIO, NIO, Red Sea, and Pacific.
• Outbreaks mainly seen in Pacific - could this be a species difference?
• Clearly more research needed, critical for coral reef management.
Overall conclusions:
1. Genetics already impacting our understanding of diversity.
2. Expect more surprises in the future.
3. Massive revision of all coral reef organisms!
Part 4 Review of Symbiodinium and bleaching.
• Dangers facing coral reefs:
• Global warming is raising the temperature of the ocean; this kills corals - “coral bleaching”.
• Also, as the oceans become more acidic, it is more difficult for corals to make their skeletons.
• Perhaps 90% of coral reefs will be dead by 2050.
• Diagram of iving tissue
• Numbers of zooxanthellate genera over time, increase in ZX genera of corals.
• More diverse than ever, showing benefits of symbioses.
• Believed to have started approximately 60 million years ago.
• Symbiodinium spp. in invertebrates holobiont=host+symbiont(s)
• Corals and symbionts
• Many shallow water corals get their energy from symbiotic zooxanthellae.
• These small animals make it possible for corals to live in the warm oceans.
• But, these symbionts are sensitive to hot ocean temperatures.
• What turns the coral white?
• As a stress response, corals expel the symbiotic zooxanthellae from their tissues
• The coral tissue is clear, so you see the white limestone skeleton underneath
• What can stress a coral?
• High light or UV levels
• Cold temperatures
• Low salinity and high turbidity from coastal runoff events or heavy rain
• Exposure to air during very low tides
• Major: high water temperatures
• Thermal stress
• Corals live close to their thermal maximum limit
• If water temperature gets 1 or 2°C higher than the summer average in many parts of the world, corals may get stressed and bleach
• NOAA satellites measure global ocean temperature and thermal stress
• How warm is warm?
• How hot do you think the ocean has to get before corals start to bleach?
• GLOBAL WARMING
• Glaciers and Sea Ice are melting
• World map showing levels of coral bleaching. Source: ReefBase
• Can corals recover?
• Yes, if the stress doesn’t last too long
• Some corals can eat more zooplankton to help survive the lack of zooxanthellae
• Some species are more resistant to bleaching, and more able to recover
• Can corals recover?
• Corals may eventually regain color by repopulating their zooxanthellae
• Algae may come from the water column
• Or they may come from reproduction of the few cells that remain in the coral
• Can corals recover?
• Corals can begin to recover after a few weeks
• Does bleaching kill corals?
• Yes, if the stress is severe
• Some of the polyps in a colony might die
• If the bleaching is really severe, whole colonies might die
• Bleaching in Puerto Rico killed an 800-year-old star coral colony in 2005
• What else can stress do to corals?
• Question: what is something that happens to people when they are highly stressed?
• What else can stress do to corals?
• Question: what is something that happens to people when they are highly stressed?
• Bleaching and coral disease
• Coral diseases are found around the world
• High temperatures and bleaching can leave corals more vulnerable to disease
• Can quickly kill part or all of the coral colony
• Bleaching and bioerosion
• We have seen that bleaching can kill part or all of a coral colony
• Areas of dead coral are more vulnerable to bioerosion (when animals wear away the coral reef’s limestone structure)
• Storms & coral bleaching
• The same warm water that causes corals to bleach can also lead to strong storms.
• Storms: a mixed blessing
• Storms: a mixed blessing
• Each passing hurricane in 2005 cooled the water in the Florida Keys.
References:
1. Dalebout et al. 2002. A new species of beaked whale Mesoplodon perrini sp. n. (Cetacea: Ziphiidae) discovered through phylogenetic analyses of mitochondrial DNA sequences. Marine Mammal Science 18: 577-608.
2. Fukami et al. 2008. Mitochondrial and nuclear genes suggest that stony corals are monophyletic but most families of stony corals are not (Order Scleractinia, Class Anthozoa, Phylum Cnidaria). PLoS One 3:9: e3222.
3. Vogler et al. 2008. A threat to coral reefs multiplied? Four species of crown-of-thorns starfish. Biology Letters doi:1-.1098/rsbl.2008.0454
Part 5: Investigating diversity of Symbiodinium: past to present.
What are zooxanthellae?
Algae that live in the coral polyp’s surface layer
Algae get nutrients and a safe place to grow
Corals get oxygen and help with waste removal
Corals also get most of their food from the algae
Symbiosis overview
Genus Symbiodinium
Described in 1962 by H. Freudenthal.
Within dinoflagellates.
Was though there was one single species worldwide.
Morphology & life cycle
Host species
Cnidaria (corals, jellyfish, anemone, zoanthids, octocorals).
Mollusca (clams, snails).
Platyhelminthes (flatworms).
Porifera (sponges).
Protista (forams).
First genetic studies
Rowan & Powers 1991.
Utlized 18S ribosomal DNA.
Sampled from corals & anemones.
Found unexpected diversity!
Recommended further genetic studies.
Second wave of studies
Used faster evolving DNA markers.
Particularly ITS-rDNA.
Even more diversity!
Zooxanthellae clade
DNA analyses
Clade: A group composed of all the species descended from a single common ancestor
Diversity
Eight major clades known.
Within each clade many subclades.
Do not know what taxonomic level clades are equal to.
Evolution and biogeography
Many studies have catalogued diversity.
Can now understand on many scales.
Can predict evolution.
Specific types
Many subclades or types associate with similar hosts.
Could be co-evolution.
Symbiodinium in Zoanthus sansibaricus
We sampled the same species from 4 locations.
Each host colony was shown to associate with one subclade of Symbiodinium.
Subclade C1/C3 was common in the north, and subclade A1 was dominant in the south.
C1/C3 has been shown to be a dominant Indo-Pacific “generalist”, with C15 common in Porites spp., and A1 a shallow-water specialist.
Modes of transmission & flexibility
2 major types; a) vertical and b) horizontal.
Vertical should result in more co-evolution and less flexibility.
Also, in horizontal, ZX from environment still rare.
Changes in ZX
over time?
Changes have been seen over time in content of ZX within coral colonies!
Particularly after bleaching events.
ZX shuffling?
Adaptive Bleaching Hypothesis (ABH).
Very controversial, large conservation implications.
Two ways this occurs.
Diversity within colonies
Same colony may have different ZX at different locations!
Differences in types
Since we know diversity, we can experiment with different conditions.
Many ZX are easy to culture.
Control light, temperature, nutrients, etc.
Can also then experiment in situ.
Symbiodinium spp. characters
Believed to alternate between a free-living stage with flagella, and a non-motile stage with chlorophyll.
Believed to sexually reproduce, although this has not been observed.
Overall morphological condition can degrade based on non-optimal environmental conditions, in particular low (<15 º C) and high (>30ºC) sustained ocean temperatures.
“Adaptive bleaching” hypothesis
Bleaching may enable corals to adopt different classes of zooxanthellae, better suited for a new environment. By:
‘symbiont switching’ (a new clade from exogenous sources) or
‘symbiont shuffling’ (host contains multiple clades and a shift in dominance occurs).
Can we protect corals from bleaching?
Marine invertebrate - Symbiodinium spp. symbioses overview
Symbiodinium spp. found in many clonal cnidarians (and other invertebrates) in tropical and sub-tropical oceans. Symbiodinium are the main reason coral reefs exist and have large levels of diversity.
Symbiodinium is now divided into 8 “clades” labelled A-H (of unknown taxonomic level) with many “subclades” (designated by numbers) within each clade (see various works by Pochon et al., and LaJeunesse et al.)
Host species’ association with various clades and subclades of Symbiodinium (often more than one) may be at least partially responsible for differences in bleaching patterns seen during bleaching events (i.e. ENSO event of 2001, etc.).
Also, some host species have been shown to have flexible associations with Symbiodinium over biogeographical ranges (depth, latitude, etc.) or time (summer versus winter, etc.). This is part of the Adaptive Bleaching Hypothesis (ABH) (Buddemier and Fautin 2004; Baker 2001), and is very contentious.
Need to understand Symbiodinium diversity within zoanthids before any discussion of symbiotic zoanthid ecology can be conducted.
References:
1. Rowan & Powers. 1991. Molecular genetic identification of symbiotic dinoflagellates (zooxanthellae). Marine Ecology Progress Series 71: 65-73.
2. Stat et al. 2006. The evolutionary history of Symbiodinium and scleractinian hosts - Symbiosis, diversity, and the effect of climate change. Plant Ecology, Evolution and Systematics 8: 23-43.
3. LaJeunesse 2005. ‘Species’ radiations of symbiotic dinoflagellates in the Atlantic and Indo-Pacific since the Miocene-Pliocene transition. Molecular Biology and Evolution 22: 570-581.
4. Pochon et al. 2004. Biogeographic partitioning and host specialization among foramineferan dinoflagellate symbionts (Symbiodinium; Dinophyta). Marine Biology 139: 17-27.
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