Coral Reef CommunitiesPatrick Smith, Michelle Franklin, Max Woerfel, Nick

Patricca

IntroductionCoral Reefs are one of the most productive

places on the EarthOnly cover .1% of the world but support a

quarter of all marine speciesMade up of calcium carbonate structuresHighly diverse

Enhances resistance to environmental perturbations

IntroductionCoral reefs are sustained by the complex

relationships between the species living thereMany symbiotic relationships

Mutualisms are especially importantCorals themselves get up to 90% of their

nutrients from symbiotic relationships

IntroductionThere are three types of mutualisms

Trophic – mutualism comes in the form of resources

Dispersive – one partner gets resources and the other gets a service

Defensive – mutualism comes in the form of services

Relationships in the Reef

Relationships- The coral reef ecosystem is a unique place

for these to occur due to the high level of biodiversity

- Remarkable for the many mutualisms which occur in the community

- Hermatypic corals and zooxanthellae- Cleaner fish and their clients- Clown anemonefish and sea anemones - Parrotfish and Rabbitfish

Hermatypic Corals and ZooxanthellaeHermatypic Corals- Make up the reef- Secrete hard calcium exoskeletonZooxanthellae- Algae capable of photosynthesis

Hermatypic Corals and ZooxanthellaeHermatypic Corals provide defense and

shelter for zooxanthellae

In return, zooxanthellae use photosynthesis to create their own nutrition

Cleaner Fish and Clients

Cleaner Fish and ClientsCleaner fish - Typically smaller fish- Most common is the Bluestreak Wrasse

Clients- Larger fish- Larger aquatic animals

- Turtles- Rays- Sharks

Cleaner Fish and ClientsThe cleaner fish nibble harmful parasites off

of their clients- Client fish are unable to do this themselves

The cleaner fish receives a cheap and quick meal of the parasites

This mutualism often develops into long term relationships where a client will visit a “cleaning station” repeatedly

Cleaner Fish and Clients http://

www.youtube.com/watch?v=TOa8y95khK8http://

www.youtube.com/watch?v=TOC2Qc2Qedw

Cleaner Fish and ClientsResearch shows this mutualism is critical to

the survival of reef communities and their biodiversity

- The bluestreak wrasse was eliminated from small reefs near Lizard Island, and kept away for 8.5 years

- Caused a 37% decrease in fish abundance, 23% decrease in biodiversity, and a decrease in size of fish

Clown Anemonefish and Sea Anemones

Clown Anemonefish and Sea AnemonesSea Anemones provide the clownfish with

shelter- When young, clownfish go through a process

called “anemone rubbing”Clownfish provide the sea anemones with

nutrients- Drag food back to the anemone- Consume zooplankton and excrete ammonia

in the anemone

Parrotfish and Rabbitfish

Parrotfish and Rabbitfishhttp://

www.youtube.com/watch?v=8T-gnZevlaY

Parrotfish and RabbitfishParrotfish- Herbivorous fish that use their specialized fused

teeth to scrape algae and invertebrates from hard coral and rocks

- Relatively defenseless against predators

Rabbitfish- Travel in schools- Have defense mechanisms of venomous spines and

color-changing for camouflage against predators

Parrotfish and RabbitfishThe Parrotfish’s grazing on algae is essential

to coral reef stability because it keeps algae from overtaking the reef and eliminating areas that fish can colonize and live in.

The Rabbitfish allows the Parrotfish to graze with its school. By doing so the Parrotfish is able to keep algae growth in check while being protected by the Rabbitfish school and their defense mechanisms.

ConservationInvasive species, eutrophication,

sedimentation, overfishing, coral bleaching, etc.

Role of anthropogenic causesReef damage is causing a shift from

specialists to generalistsDue to destruction of small niches

This shift can cause huge drops in species richness

Future ResearchCurrently there is much debate about how

big of an effect anthropogenic stressors are impacting the degradation of coral reefsSome scientists believe most is natural

disturbancesOthers believe it is anthropogenic

Important research could be determining how much humans are effecting the degradation

Future ResearchThe resilience of coral reefs is important due

to the current rate of degradationFuture research should concentrate on if and

how coral reefs can recover

Future ResearchIt would be extremely helpful to further look

into the mutualistic relationships that occur in coral reefs

Removal studies like the one done on the bluestreak wrasse would give insight to the importance of the mutualisms

SummaryThe health of the reef depends on the

complex relationships occurring in the ecosystem.

High diversity, which can be seen by the amount of mutualistic relationships, can indicate the wellbeing of the reef.

Once diversity is lost it can not be recovered