Report Information

Coral Reef Diversity and Conservation 2014-15

J.D. Reimer

Assignment Information:

You must apply for research funding for the following research grant:

The MISE Coral Reef Biodiversity Fund

This fund provides grants for projects that investigate ways to protect coral reef associated animals. You must do research in Okinawa. You must use both traditional (field work, morphology) and modern (DNA, satellite tracking or imaging, etc.) techniques. Projects will be for two years from April 2015.

Your maximum budget is 5,000,000 yen.

Application: please submit the following to Science room 353 by 17:00 on Friday, February 6^th.

1. Research background and goals (1 page maximum): Provide a background that anyone with science training can understand, clearly state the project goal(s) and the animal(s) you will investigate, and explain the necessity of the project. You will get more marks for more/better references. You will get less marks if no references.

2. Methods (1 page maximum): Include detailed explanation of methods used, and a concrete timeline to be followed for two years. For field work, explain where you will go, and how you will collect samples, etc. For morphology, explain what data you will collect and why, etc. For DNA methods, please include details such as how many samples, what DNA markers you will use, etc. A realistic budget is needed.

3. Expected results (1 page maximum): Describe concretely what results can be expected, how these results will benefit coral reef science, and how these results will benefit future coral reef conservation research in Okinawa.

Hints:

Please remember these points:

i.      Your plan must be realistic, and must include as many details as possible to make it easy to understand. It can be as simple or large-scale as possible. The ideas must be logical. The plan can build on other plans, but these plans must be referenced.

ii.      Using scientific references increases the amount of knowledge you have access to. On the other hand, using information without references will decrease your score. Use Google Scholar or other sources of information to access scientific literature quickly. Space is limited, so choose references well.

iii.      Figures and graphs greatly help make ideas easy to understand. For budgets, catalogues may be useful. Please visit JDR’s lab to borrow any catalogue you need.

Marking:

Grades will be assigned based on:

1. originality (new ideas, etc.):                                           25 points

2. necessity:                                                               25 points

3. realistic possibility:                                                           25 points

4. background research:                                                      25 points

Other information:

l   This report and presentation is 40% of your final mark (final test is 40%, small tests are 20%).

l   Your report should be done alone, or with someone else. I expect twice as much information from a 2 person team (e.g. 6 pages)!

If you have any questions or problems please contact JDR as soon as you can, either at his office or by e-mail.

January 21, 2015 class notes

Conservation (continued).

Part 1 - 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?
Part 3 - Looking towards the future (De'ath et al. 2012)~50% of coral lost in GBR in last 27 years!!Loss due to:Storms (48%)COTS (42%)Bleaching (10%)
So, is conservation really working?What can be done to stop this loss?Focus on COTS possible.
Conclusions (1):1. Increased connections in the world are increasing biological invasions.2. Invasions can be rapid and irreversible.3. Large scale management often needed, and international cooperation.4. Coral reef biodiversity patterns different from land; different management needed.Conclusions (2):1. Coral reefs are linked to other ecosystems, both marine and on land.2. Conservation plans must protect linked areas and ecosystems, and not “islands”.3. Protected areas should be decided based on endemism, geographic features, neighboring ecosystems, etc.4. Successful conservation involves all levels of people, but most important are locals.5. Without demonstration of monetary value, coral reef protection very vulnerable to politics.6. In the future, more conservation plans will be implemented.
7. The gap between well protected areas and those not protected will widen.
8. Very few non-protected reefs will survive.
We must do MORE!Conclusions (Okinawa)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.
References cited:1. GBRMPA Conservation Plan.  3. De’ath et al. 2012. The 27–year decline of coral cover on the Great Barrier Reef and its causes. PNAS 10.1073/pnas.1208909109

January 14, 2015 class

Part 1: 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 2: Activity

Situation:
You are the mayor of a small coral reef island (~300 people) in a semi-poor country.
Pressure on the coral reef is growing (tourism, fishing).
Questions:
What data do you need?
What conservation plans do you make?

Part 3: Community conservation in the Philippines.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 stepsIntegration 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.
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.

References
1. 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 7, 2015 class notes

Happy New Year!!

January 7, 2015 class notes

*****Notice*****
Next week (1/14) - report assignment. Please attend!

Activity: What are the most dangerous threats to coral reefs? Rank 1-6 as you see fit:
a. bleaching/climate change
b. acidification
c. pollution/run-off
d. over-exploitation, development
e. crown-of-thorns starfish
f. disease

Outline

1. Quick introduction to diseases.

2. Common coral reef diseases.

3. Why are diseases becoming common?

4. How do diseases affect conservation?

5. 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 andO. himal-ulmi.

Part 2: Common coral reef diseasesIntroduction 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: 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.

December 24, 2014 class notes

Class notes for December 24, 2014
Note: Short test @ end of class!Recent Research: Symbiodinium introduction & diversity studies

Outline:

1. Review of Symbiodinium and coral bleaching.

2. Bleaching in Thailand, 2010.

3. Symbiodinium diversity.

Part 1: 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.

Part 2: Coral bleaching images from Phuket, Thailand in 2010

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.

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, coral bleaching hot spots, degree heating weeks.

Part 3: 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 Poritesspp., and A1 a shallow-water specialist.

In Okinawa, shallow and deep populations of Z. sansibaricus.
Shallow colonies had Symbiodinium clade A1, or C1z.
Deep colonies had different type; C1zd.
Similar results seen in hard corals.
Suggests many species of Symbiodinium.

Recent news!

Types described using various DNA markers.

Supported with morphological and ecological data.

Suggests 1000s of species of Symbiodinium. (see below)

Without names, these species cannot be protected.

History of diversity of Symbiodinium research:

1962 - 1 species described by Freudenthal.

1990s - clades - using ribosomal DNA - perhaps 8 or 9 types?

2000-2010 - subclades, variation within clades using ITS2

2010-now - even more - 1000s of species? cp23, psbA.

How different researchers understand Symbiodinium diversity affects even policy decisions and your views on ABH.

 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 data-blogger-escaped-and="and" data-blogger-escaped-c="c" data-blogger-escaped-high="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 9 “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.
5. Reimer et al. 2006. Latitudinal and intracolony ITS-rDNA sequence variation in the symbiotic dinoflagellate genus Symbiodinium (Dinophyceae) in Zoanthus sansibaricus (Anthozoa: Hexacorallia). Phycological Research 54: 122-132.
6. Kamezaki et al. 2012. Different zooxanthellae types in populations of the zoanthid Zoanthus sansibaricus along depth gradients in Okinawa, Japan. Marine Biodiversity (online).
7. LaJeunesse et al. 2012. A genetics-based description of Symbiodinium minutum sp. nov. and S. psygmophilum sp. nov. (Dinophyceae), two dinoflagellates symbiotic with Cnidaria. Journal of Phycology (in press).