L3-life histories,ecology,larval dispersal

Question 1

Why are marine systems different?

Answer 1

different physical medium
– Density of seawater
– Developmental medium
– →Dispersive larval stages

Question 2

what does planktonic mean?

Answer 2

live in water column

Question 3

what does benthic mean?

Answer 3

live on the ground

Question 4

What is the difference between terrestrial and marine systems?

Answer 4

Dispersal distances can be much greater than in ocean than terrestrial systems and more varibility

Question 5

What controls larval dispersal distance?

Answer 5

taxonomic differences-seaweed not far fish very far

Question 6

What is the Demographically of ocean environments?

Answer 6

‘Open’ populations
Populations demographically connected

Question 7

What are source sink dynamics?

Answer 7

some pops produce offspring while some only receive

Question 8

How connected are marine systems?

Answer 8

Very connected little differentiation among nearby
populations in neutral markers

Question 9

What are the Management consequences of high dispersal?

Answer 9

• Invasive species spread
• Pollution transport

Question 10

What makes a good Marine Protected Areas?

Answer 10

5 key features:
no take-no fishing
well enforced
old-10years
decent size
isolated by deep water or sand

Question 11

How large does an MPA need to be?

Answer 11

at least as big as the home range of the adults

Question 12

What determines distance between?

Answer 12

larvae dispersal(want to be able to get from one mpa to the other)

Question 13

how do MPA effect fish yield?

Answer 13

enhance catch
adults from protected area goes into unprotected(spill over)

Question 14

Which is better fishing limits or MPA for fish yield?

Answer 14

for most species there is a benefit and some double the catch

Question 15

for what species are MPAs best?

Answer 15

species with long life histories

Question 16

When does most dispersal occur?

Answer 16

Larval dispersal is where most dispersal happens for most species

Question 17

How to track larvae?

Answer 17

Chemically mark larvae
eg. Otolith microchemistry

Question 18

Do all species disperse?

Answer 18

some groups 90% adults come from the same locations as birth

Question 19

Why don’t more larvae come from
elsewhere?

Answer 19

• Dispersal barriers? Probably
• Larval mortality? Probably
• Costs of dispersal?For some species
• Local adaptation? No idea really

Question 20

What causes Larval mortality?how is it a problem for science?

Answer 20

predation
hard to study

Question 21

Why is the costs of dispersal important?

Answer 21

• Some larvae don’t feed while in the plankton Burning resources
Larvae that swim for longer have much less reproduction

Question 22

Evolutionary barriers?

Answer 22

species adapt for local conditions will have little success if come from area with different conditions