Coral Reefs

8. How are the individual polyps connected to each other within the coral colony?

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6. What are some of the feeding strategies of reef fish (e.g, herbivores, planktivores, predators)?

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8. What is a colony?

8. Several polyps

16. What is bioerosion?

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1. How do hermatypic corals feed?

1. Hermatopic corals feed off both zooxanthellae and by using their tentacles to capture small plankton and fish

16. Where do zooxanthellae live within the coral reef? Why?

16. They live inside the coral polyps but can also live outside host

2. How does the fish biodiversity of coral reef change within the different oceans?

more eastern oceans have more species diversity of fish and vice versa

1. What are shelf reefs?

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1. What are the main families of fish found on coral reefs and what are some of their main characteristics?

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12. How does climate change hurt coral reefs?

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12. What are the major components of the trophic pyramid typical of coral reefs?

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13. What are primary producers, primary consumers, secondary consumers and tertiary consumers?

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15. What is plankton? What is phytoplankton and zooplankton?

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16. What are some of the most common coral pathogens?

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17. How do predators and competition affect coral reefs?

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17. What examples of protection did we talk about?

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17. Why and how do corals compete with algae?

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18. How does bioerosion affect coral reefs

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18. How is predation within coral reefs?

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18. What other types of mutualistic relations -other than the corals and zooxanthellae-- did we talk about?

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19. What are some of the animals that prey on corals?

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19. What examples of disturbance did we talk about?

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2. What are oceanic reefs?

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22. How do parrot fish prey on corals? What are some of the consequences of their preying on corals?

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23. What is grazing? Why is it important within the coral reef ecosystem?

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3. What are Octocorallia?

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3. What are the four different theories that try to explain the high diversity of fish species found in coral reefs?

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4. What are Hexacorallia?

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4. What are some of the important consequences of day night changes in fish population in coral reefs?

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5. What is the difference between Octocorallia and Hexacorallia?

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6. What are coral polyps?

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7. How is coral polyp body organized (symmetry, mouth, etc)?

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7. How is the distribution of different species of zooxanthellae within the reef?

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9. What are some of the important characteristics that we discussed in class about crinoids?

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1. What is coral reef zonation? What is it based on?

1. Coral reef ecosystems contain distinct zones that represent different kinds of habitats. Based on depth, bottom topography (sand & rocks), and waves.

1. How would you describe the geographical distribution of reef building corals?

1. Coral triangle in the Indian and Pacific Oceans

1. What is a coral?

1. Its an animal which may live with a plant and makes a mineral based skeleton (rock, limestone, mineral, aragonite, CaCo3)

1. What are coral reefs?

1. Rock-like structures made of calcium carbonate produced by living organisms- mainly corals and algae.

1. Describe the extent of the biodiversity typical of coral reefs.

1. • Coral reefs house between 600,000 and 9 million species • 25% of marine species rely on coral reefs at some point in their life cycle • 32 of the 34 phyla of metazoans live on reefs • 65% of marine fishes live in reefs

1. Why are coral reefs important?

1. • Protect shores from erosion • Protect shores from flooding • Provide popular tourist attractions • Provide food for coastal communities • Create products formedicines

10. Describe the main characteristics of the reef flat.

10. Area of lower energy where fragile, branched coral are relatively common, Very shallow and flat → Poor coral growth → Exposure at low tides (erosion)

10. What are gonochoric corals?

10. Internal or external fertilization

10. How does pollution from oil hurt coral reefs?

10. It's a non point-source pollution: - 51% of the oil entering the oceans is from runoff - 5% is from big spills - 19% is from routine maintenance - 2% is from offshore drilling - 13% is from burning fuels (e.g. car exhaust) - 10% is from natural seeps

9. What is photosynthesis? What is respiration?

10. Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of sugar. This process occurs in plants and some algae (Kingdom Protista). Plants need only light energy, CO2, and H2O to make sugar. Respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.

10. What are nematocysts?

10. Polyps tentacles that trap prey and shocks them

10. What are some of the other environmental factors that control the distribution of reef building corals?

10. Salinity, sedimentation, nutrients, moderate water motion, and emersion

10. What are some of the characteristics of Puffers that we discussed?

10. four large teeth fused into upper and lower plate used to crush shells of crustaceans and molluscs, puffers move eyes independently and can change color, Can inflate their bodies by swallowing water → Have a beak made by 4 fused dental plates → Eat urchins, sponges, corals, starfish, crabs, molluscs, worms, tunicates, algae → Produce powerful poison

11. What are the two strategies for sexual reproduction used by corals?

11. Most are broadcast spawners Few are brooders

11. Describe the main characteristics of the reef crest.

11. Often rich in algae, only encrusting corals survive here, Highest energy zone → Very intense light levels → Limited coral growth → Dominated by coralline algae

11. What are hermatypic corals?

11. Produce reefs, Found only in tropical regions, Have small symbiotic algae called zooxanthellae living in their tissue, Zooxanthellae are critical for reef growth & development

11. How does coral reef productivity compare to the productivity of other oceanic areas?

11. Significantly higher

11. What are some of the characteristics of Butterfly fish that we discussed?

11. small, laterally compressed bodies, generally diurnal, shallow water, can be territorial, most feed on coral polyps and sea anemones, brightly colored, many have eyespots on flanks, Generally diurnal → Live in shallow waters → Especially territorial, form mated pairs → Hide between coral reef crevices

11. How can overfishing hurt coral reefs?

11. • Changes trophic structure • Many large predators are no longer present • Grazing fish species are being collected as food fish • May allow algal overgrowth of corals

12. What are broadcast spawners?

12. Broadcasters release both sperm and eggs in water where fertilization and development occur

12. What are ahermatypic corals?

12. Do not form reefs, Are distributed worldwide (in polar, temperate & tropical waters), Most do not have zooxanthellae

12. What are some of the characteristics of Parrot fish that we discussed?

12. Mostly tropical fish → Teeth arranged to form a parrot-like beak → Eat a variety of organisms - algae and corals → Their feeding behavior is important for production and distribution of coral sand

12. Why is it a paradox? And what are some of the possible explanations?

12. Paradox is that coral reefs have such high productivity in nutrient poor areas. Reasons why: very efficient relationship between coral and zooxanthellae, high flow rate of water over reef, and rapid recycling of nutrients (high levels of bacteria)

12. Describe the main characteristics of the slope.

12. massive, branching corals and sponges, Optimal coral habitat → Dominated by reef-building corals → Most diverse zone → Different species at different depth

13. What are the main resources that corals compete for with each other?

13. Compete for space and light

13. What are brooders?

13. Eggs develop into larvae internally, Larvae are released, often at night, in response to the lunar cycle

13. What are some of the characteristics of Snappers that we discussed?

13. Feed on small fish and other organisms → Short, sharp, needle-like teeth → Gregarious, form large schools → Red snapper: stays close to bottom -- rocky areas

13. What is the difference between hermatypic and ahermatypic corals?

13. hermatypic produce reefs while ahermatypic don't produce reefs

13. Why are higher levels of CO2 in the ocean potentially bad for coral reefs?

13. • An increase in CO2 dissolved in the ocean causes a lowering of the pH of ocean • As a consequence, CaCO3 dissolves or doesn't form properly •O rganisms with shells or skeletons made of CaCO3 are affected

14. What are some of the characteristics of Jacks that we discussed?

14. Black-jacks live alone or in small groups → Benthopelagic, live in the open ocean → Fast swimmers → Hunters, chase their prey

14. What is exploitative competition?

14. Exploitative competition is being the best at what they're trying to get (light), branching corals grow rapidly to over shadow other corals, best to have the limited resources

14. How does global warming hurt coral reefs?

14. More bleaching from stress from heat

14. What are some of the differences between spawners and brooders?

14. Spawners (broadcasters) release both sperm and egg, only 1-2 reproductive cycles/yr Brooders release only sperm, eggs develop into larvae internally, up to 12 cycles a year

14. What are zooxanthellae? What are dinoflagellates?

14. Zooxanthellae are single- celled algae, dinoflagellates -- also form red tides • They have different colors: brown, green, yellow • Dinoflagellates live in association with other groups: sea slugs, giant clams, tunicates

14. What is seagrass?

14. → Are flowering plants (not algae) → Live in shallow water and muddy or sandy bottoms → Harbor many different species → Ecosystem engineers → High productivity

15. What are some of the characteristics of Barracudas that we discussed?

15. Can be found alone or in schools → Also occurs in the open ocean → Voracious predators → Hunters, use ambush strategy → Do not care for youngs

15. What is interference competition?

15. Interfering with another coral damaging it to get light and space

15. How does CO2 enter the ocean and what happens to it when it does?

15. Lowers pH level of ocean so CaCO3 dissolves or doesn't form properly

15. What is a planula larva? How do they become adult corals?

15. Planula Larvae: fertilization of gametes form a microscopic free-swimming larva (planula), covered in cilia used to swim, swim for 2 days up to 2 months close to the water surface before they settle on the bottom of the ocean, once they attach on the floor they metamorphose into polyp and start to form a new colony through asexual reproduction

15. What is mutualistic symbiosis?

15. Zooxanthellae live in symbiosis with corals • They live in the coral polyp's surface layer where they perform photosynthesis • Algae get nutrients and protection • Corals get oxygen, help with waste removal and food • It is a mutualistic symbiosis

16. What are some of the characteristics of Sharks that we discussed?

16. Apex predators → Viviparous → Some live in small groups → Whitetip shark is bottom-dwelling and nocturnal

16. What are the two ways in which zooxanthellae are transferred to new coral colonies?

16. Maternal transmission: passed from parent to offspring, through eggs or planula. Environmental transmission: new with every new generation through direct ingestion

16. What are some of the adaptations of corals in response to competition? What are sweeper tentacles?

16. Mesenteric filaments can kill or devour other coral polyps through a process similar to digestion. Sweeper tentacles form the outermost portion of the colony and act as a "patrol" along the periphery

17. What are cleaning stations?

17. A specialized form of predation in which some small fishes or shrimps remove various parasites from other fish

6. What are the two types of asexual reproduction for corals?

17. Broadcast spawning and brooding

18. Briefly explain the cleaning behavior of some coral fish.

18. Cleaning stations are set up where fish visit for cleaning

19. Briefly explain the schooling behavior of some coral fish.

19. Defense against predators • Hydrodynamic efficiency • Foraging advantage

19. How does marine debris affect coral reefs?

19. Sedimentation suffocation

2. Why are scientists concerned about the future of coral reefs?

2. If destruction increases at the current rate, 70% of the world's coral reefs will disappear within 50 years

2. What are the major zones within coral reefs?

2. Lagoon, reef flat, reef crest, reef slope

2. What is the taxonomic classification (phylum, class, subclass, order) of stony corals?

2. Order Scleractinian

2. Where do you mainly find them?

2. Shallow tropical water environments - often close to the coast.

2. How does temperature control the distribution of reef building corals?

2. Temperature controls geographic distribution, zooxanthellae are very sensitive to temperature (need warm temp), controls precipitation of coral skeleton, and corals can grow btw 18-40 Celsius but optimal 23-25 Celsius

2. How important are zooxanthellae for corals nutrition?

2. Zooxanthellae give energy through photosynthesis that produces sugar, food, and oxygen.

20. How do corals respond?

20. Corals may regrow polyps to cover destroyed area if damage is not extensive

20. How does runoff affect coral reefs?

20. Freshwater input, pollutants and pesticides, sediment, makes algae happy

21. Why are the crown-of-thorns starfish so damaging for coral reefs?

21. Crown-of-thorns starfish are capable of destroying coral colonies.

21. How does nutrient enrichment affect coral reefs?

21. Overgrowth of algae

24. What are some of the consequences of grazing for the algal community of a coral reef? How do algae try to protect themselves from grazers?

24. Grazing can result in shifts in abundance of algae species. Algae try to protect themselves by becoming unpalatable by secreting CaCo3 in the tissues, producing chemicals that are poisonous to grazers, and live in areas of the reef that provide refuge from grazers.

25. What are some of the benefits and costs of the zooxanthellae-corals symbiosis for zooxanthellae, corals, and coral reefs?

25. A. Benefits: i. Polyp 1. Supply of simple sugars 2. Increased growth & reproduction 3. Increased calcification 4. Conservation of nutrients ii. Zooxanthellae 1. Supply of CO2 and nutrients 2. Permanently in photic zone 3. High population density 4. Protection iii. Coral Reef 1. Increased growth to compete for space on the reef 2. Higher calcification= stronger coral and greater resistance against wave damage etc. B. Costs i. Polyp 1. Vulnerable to the environmental stresses of plants 2. Can't reject foreign, unwanted cells 3. Lose defense against UV damage ii. Zooxanthellae 1. Give significant amount of food away 2. Grow more slowly inside coral 3. Possible expulsion from host 4. Supply of CO2 and nutrients limited by the host iii. Coral Reef 1. Restricted tolerance of light, tempratures, sediment and growth 2. Sensitivity to environmental stresses compounded

3. What are some of the growth forms of corals?

3. Branching, massive looks like a brain, encrusting grows on rocks, plate-like, and free living

3. How does depth control the distribution of reef building corals?

3. Depth Controls amount of light available in the water, corals grow shallow only down to 50-70m deep

3. What portion of the coral reel is alive?

3. Only the top layer of the coral reef is alive, as animals die their old shells are incorporated into the reef structure and contribute to 'land building'

3. What are some of the important characteristics that we discussed in class about coralline algae? What is their main role on corals reefs?

3. Red algae → Deposit CaCO3 within cell walls → Encrusting → Help cement reef together → Particularly important on reef crest

3. How do corals capture their prey?

3. Use tentacles and associated nematocysts to capture small plankton and even small fish, tentacles bring prey into stomach

3. What is a fringing reef?

3. develop on the edge of continental landmasses, Youngest reefs → Attached to the shore → Shallow water

3. What is the present status of coral reefs?

3. • 11% of reefs have been lost • 16% of reefs severely damaged • ~60% of studied reefs threatened by human activities • No pristine reefs left • Example Caribbean Reefs: - 1970s: ~50% coral cover - Present: ~10% coral cover - 80% reduction in coral cover over last 30 yrs

4. What are the challenges facing reefs?

4. - Diseases (bleaching, pathogens) - Disturbances (storms, hurricanes, tsunamis, volcanoes, earthquakes, predators and competitors) - Bioerosion by fishes and other marine organisms - El Niño - Pollution - Sediment runoff (smothering by sediments from deforested land, which also carry new pathogens) - Coastal development (ship damage) -Overharvesting, aquarium trade (dynamite damage, poisoning by cyanide fishing techniques, anchor damage) - Climate change (global warming; increased ultraviolet radiation; ocean acidification)

2. Which are some of the organisms that we can find associated with coral reefs?

4. Echinoderms (sea urchins, sea cucumbers, starfishes, crinoids), Crustaceans, Marine worms, Fishes, Bacteria

4. What are some of the important characteristics that we discussed in class about sponges? What are filter feeding organisms? Why are they important?

4. Help clean and filter surrounding water → Need constant water flow through their bodies → Skeleton can be made of CaCO3 → Can have endosymbionts

5. What controls the depth of the part of the reef that is growing (active coral reef)?

4. How fast a volcano sinks

4. How does light control the distribution of reef building corals?

4. Light is needed to allow photosynthesis

4. How do corals use their cilia and mucus?

4. Mucus traps small organic particles and are moved over the coral bodies by the cilia and pulled into the mouth

4. Over how long of a time span can coral reef develop?

4. Reefs develop over thousands of years

4. How would you describe the overall trend in the change of coral shape within a coral reef going from the shore toward the open ocean? Which factor is most important in controlling this change?

4. Stronger corals are closer to shore (brain & massive corals) and branching corals are weaker and at deeper waters

4. What is a barrier reef?

4. develop on the edge of continental landmasses, farther offshore, Parallel to the shoreline → Separated from the shore by a lagoon

5. Approximately how much do they cover of the Earth's surface?

5. .71% of earth's surface

5. What is an atoll?

5. Atoll: ringed shaped with only lagoon at the center (no land mass) - develop on top of seamounts, enclose a lagoon, and no land inside

5. How do light and zooxanthellae aid the calcification of coral skeletons?

5. Light is needed, Zooxanthellae increase the calcification rate of corals and the growth rate of coral colonies, Perhaps light stimulates O2 production, which stimulates coral metabolism and leads to increased CaCO3 deposition

5. What is the process of calcification? Where does it occur in corals?

5. Process in which Ca builds up to form a solid mass, coral skeleton is composed of aragonite, which is CaCO3, rate of deposition varies greatly across species and environmental conditions and it is light dependent.

5. What are some of the important characteristics that we discussed in class about bivalves and specifically Giant Clams?

5. Two-part shell → Most are filter feeders → Epifauna and infauna, Giant Clam: Mantle contains Zooxanthellae

5. What is coral beaching? Why is it called 'bleaching'?

5. • Bleaching is a response that corals have to stress • It is one of the main causes of coral reef death • Healthy corals have a color which comes from zooxanthellae • When corals are stressed, they expel the zooxanthellae from their tissues and because coral tissue is clear, you see the white limestone skeleton underneath - bleached corals

6. What causes coral reef to bleach? What can stress coral reefs?

6. - 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

6. What is aragonite?

6. Aragonite is CaCO3 - makes up coral skeleton

6. Which scientist first developed a theory to explain the occurrence of atolls?

6. Charles Darwin

6. Which factors do you think are most important in determining the zonation within a coral reef?

6. Depth, sedimentation, and wave energy

6. Why are coral reef important?

6. Home to huge variety of organisms (25% of all marine life), breeding and feeding ground for any fish and other organisms, 1/3 of all ocean fish live on or depend on coral reefs, protect shorelines from erosion and flooding, and recreational use

6. What are some of the important characteristics that we discussed in class about nudibranchs?

6. Shell-less marine gastropods → Extremities on back used to breathe → Most are carnivorous

7. Describe the subsidence or compensation theory.

7. -Fringing reefs begin to grow on the shores of newly formed volcanic islands - The islands eventually begin to sink - Barrier reefs are formed if the islands do not sink too fast and reef growth keeps up with them - Eventually the islands become seamounts and with continued growth of the reefs, atolls are formed

7. What are some of the important characteristics that we discussed in class about starfish? Give an example of a starfish that can have a deep impact on the coral reef ecosystems.

7. Five-fold radial symmetry → No external skeleton → Endoskeleton: water vascular system, Starfish: Hydraulic vascular system aids in locomotion, Two stomachs, Predators

7. How do coral reefs, coral heads, and polyps compare to cities, apartment complexes, and single people?

7. Individual people are called polyps, several polyps (apartments) make up a colony (coral heads), and colonies make up a city (coral reef).

7. What is the relation between depth and light in the ocean?

7. Relation btw depth and light is that the deeper the water the less light gets through to the coral

7. What is budding?

7. To increase size of the colony

7. How can corals recover from bleaching?

7. Yes, if the stress doesn't last too long - Corals may eventually regain color by repopulating their zooxanthellae - Corals can begin to recover after a few weeks

7. What are some of the characteristics of Tangs that we discussed?

7. spines on either side of the tail, single row of teeth used to graze algae, many brightly colored, Primarily graze on macroalgae → Tropical fish → Small mouth with single row of teeth, Typically small → Efficient carnivores, feeding on small invertebrates → Some are symbiotic - cleaning stations → Can bury in sand at night

8. What are some of the important characteristics that we discussed in class about sea cucumber?

8. Collagen forms body walls → Scavengers → Can release toxins

8. What are hot spots? How are they connected to seamounts and atolls?

8. Connected to seamounts because as seafloor/continent moves over a hot spot successive eruption produces a linear series of seamounts. In tropics volcanoes erode very rapidly but below sea-level erosion rate is much slower, allowing Atolls to exist for long periods.

8. How do hurricanes hurt coral reefs?

8. Physical damage • Smothering • Freshwater poisoning • Destruction of other ecosystems upon which coral reefs depend • The same warm water that causes corals to bleach can also lead to strong hurricanes

8. What is fragmentation?

8. To start new colonies

8. Describe the main characteristics of the lagoon.

8. Variable depth, Covered in coral sand, Nutrients and sediments from the reef front, Patch reefs or isolated large stands of corals

8. What are some of the characteristics of Wrasses that we discussed?

8. typically small, carnivorous, feed on small invertebrates, protactile mouth, brightly colored, some are symbiotic fish that set up cleaning stations

9. What is a corallite?

9. Area of the skeleton where the polyp lives

9. What are hermaphroditic corals?

9. Self- or cross- fertilization

9. Describe the main characteristics of the back reef.

9. Shallow and closest to shore, Low energy and high sedimentation, Fluctuating T and S, Small patch reefs, sand and seagrass

9. Why is the Great Barrier Reef expanding to the south along the east coast of Australia?

9. The Great Barrier Reef is expanding to the south along the east coast of Australia because Australia moving north went from cold to tropical water and more of the continent is in the tropics meaning it can have more reef growth and sustain tropical reef life.

9. How do El Nino events hurt coral reefs?

9. The trade winds don't push the water as much to the west, so the corals used to warm water are cold and the corals in the east used to cold water are too warm, so they bleach from the temperature induced stress

8. Where are zooxanthellae within the corals? Why?

9. These algae live in the coral polyps endoderm where they perform photosynthesis

9. What are some of the characteristics of Moorish Idols that we discussed?

9. resembles butterfly fish, feeds on benthic invertebrates, Long, tubular snouts with a small mouth → Many long bristle-like teeth → Prefer flat reefs → Feed on benthic invertebrates → Diurnal, stick to reef bottom at night → Mate for life

10. What are some of the important characteristics that we discussed in class about crustaceans and specifically Spiny Lobsters?

Arthropods → Stiff exoskeleton, Spiny lobster: live in crevices - Predators (active at night) - Exhibit social behavior - Produce sound to repel predators

11. What are some of the important characteristics that we discussed in class about marine worms and specifically Feather Dusters?

Belong to different phyla → Polychaetes are segmented worms - Feather dusters are tube-dwelling polycheate - Some make tubes with cemented mud or sand, some with CaCO3 - Colored crown of tentacles - Tentacles are extended for feeding and breathing