coral classification + ecology

Question 1

growth limits - bc temp and light?

Answer 1

• Temperature & Light –> - most at 25-50m

* Light impact -too bright or intense = can bleach

Question 2

growth limit - how do they deal w too much light

Answer 2

• - can have mycosporine-like amino acids (protect from high sunlight)- sunscreen! Fragment the light - photoprotective

Question 3

growth limit - temp?

Answer 3

• Corals are resistant to temps but have a narrow range -usually 25-30 degrees

Question 4

reading on global warming and acidifiaction.

Answer 4

ok

Question 5

growth limits - bioerosion? parrotfish ex

Answer 5

• Bioerosion –> by fish/invertebrates
○ Fish eating the coral- humans have fished a lot of the ones that eat the coral - ex
○ parrot fish Eat chunks of coral - beach sand is parrot fish scat :(
○ Can stimulate growth - not always bad
○ without them/ with less of them - Not as much bioerosion - but now they don’t grow as much

Question 6

ex of top down effects on reefs caribbean nassau

Answer 6

• Many studies of top-down effects on reefs (ex. Caribbean Nassau Grouper, when near humans or not, e.g. hawaiian island reef tracts - 1 near humans 1 not)
○ Top down effects - categorize what fish are there when they study, before they go down
○ Humans prefer larger fish - caught and sold more
§ Ex. Caribbean Nassau Grouper - caught and sold for eating - fished out predatory fish in reef system - get explosions of smaller invertebrates as a result = excessive bioerosion from starfish
§ Explosion of the parrot fish - reef system starts to die off
§ Not allowed to fish on certain hawaiian islands - protected

Question 7

impact of storms on coral?

Answer 7

hurricane damage - excessive storm can destroy them - broken into small fragments

Question 8

impact of diseases on coral

Answer 8

○ diseases (white band, white plague, black band, brown jelly syndrome). - infection - coral is necrotic - not bleaching - distinctive features

Question 9

coral predation?

Answer 9

• Predation –> Corals eaten & have defenses
• Ex. Small invertebrates graze coral (like gastropods) - some coral are toxic - contain high levels of hormones - taken in by invertebrates and used
lots of defense mechanisms include hormones - ie. Incorporate coral toxins into their systems

Question 10

coral competition/ alleopathy?

Answer 10

• Competition (allelopathy) –> corals compete for space & light - indirect & contact killing - tentacles for feeding or attacking neighbors - can also release tentacles into the water column

Question 11

great reef paradox?

Answer 11

reat Reef Paradox: faster growing corals do not dominate (grow to survive being killed by slower species) - ones growing fastest are not the most successful - slow growers are better at “hunting” - faster growing are just growing to survive

Question 12

contact kill?

Answer 12

○ Contact kill ex - grows over and occupies area - tentacles to kill it
○
• Fighting, one digesting the other

Question 13

mutualism exs.

Answer 13

ok

Question 14

why are corals hard to classify?

Answer 14

• Corals = can have various morphs.
○
○ Same species - very different looking morphs
○ Coral taxonomy does not rely as much on morphology

Question 15

what do coral morphs complicate?

Answer 15

Complicates conservation - morphs might be classified as a species - endangered but its not actually

Question 16

difficulties w identifying coral + example - order to identify them

Answer 16

• difficult to identify - follow order: (identify species using a mix of genetic, morphology, & ecology).
  
  • Difficulty with sibling species (closely related, look very similar) also difficult to identify

Question 17

ex of coral identification issue

Answer 17

○ ex. Montastrea annularis - 3 forms lumped into 1 —> now know 3 species = M annularis, franski, and faveolata
○ . ▪ All 3 mass spawn*
○ Faveolata based on molecular, enzyme polymorphism, corallite structure, and life history

Question 18

coral hybrids in lab?

Answer 18

○ M. faveolata (most distinct, hybridizes poorly)
○ M. annularis & franski (hybridize easily) -
○ M. franski spawns 2hrs ahead of others- - separation of a few hours - another argument for separate species along w genetics
○ M. faveolata & annularis (spawn together but incompatible gametes on reef system)
- Hybrids unlikely in Montastrea: spawning timed differently, sperm aging, gamete dilution & incompatibility

Question 19

other possibility of identifying coral?

Answer 19

Another possibility is plasticity: allowing local adaptation specialization - flexibility of morphs
ex. Montipora species complex