Midterm 3

Question 1

what is a toxicant

Answer 1

synthetic, human-made toxic chemicals

Question 2

what is a toxin

Answer 2

poisons produced within living cells of organism

Question 3

what does risk =

Answer 3

risk = toxicity x exposure

Question 4

what are the factors that affect risk

Answer 4

dose
exposure route
ability to be absorbed
species life stage
metabolism
excretion
presence of other chemicals

Question 5

what are 2 examples of oil spills

Answer 5

Exxon valdez

deepwater horizon

Question 6

what is bioaccumulation

Answer 6

the process by which chemicals build up in an organism over time

Question 7

what is biomagnification

Answer 7

process by which toxic substances increase in concentration as they move up the food chain

Question 8

what are persistent organic pollutants

Answer 8

long-lasting chemicals that resist degradation and accumulate in the environment

Question 9

through what ways are POPs prone to long range transport

Answer 9

via atmospheric transport and deposition

Question 10

what are the pollution types

Answer 10

contaminants
nutrient enrichments
sedimentation
plastics
light/noise

Question 11

what are 2 examples of POPs

Answer 11

DDT - pesticide/insecticide

PCBs - heat resistant transformer fluids

Question 12

why was DDT bad

Answer 12

it bioaccumulated in birds (upper trophic level) and caused egg shell thinning

Question 13

how do POPs affect marine organisms

Answer 13

altered behaviour
reproductive impairment
birth defects
physiological changes
endocrine disruptions
immune system impairment
inhibition of photosynthesis

Question 14

what is 6PPD - quinone

Answer 14

added to tires, released through run off from roads

Question 15

what are point sources

Answer 15

waste water discharges (ex storm drains, sewage pipes)

Question 16

what are non-point sources

Answer 16

urban/agricultural runoff
(ex: fertilizers, road oil, litter)

Question 17

what is eutrophication

Answer 17

Eutrophication is a general term describing a process in which nutrients accumulate in a body of water, resulting in an increased growth of organisms that may deplete the oxygen in the water

Question 18

what are the consequences of sedimentation

Answer 18

impaired filtering
larval survival
fertilization
survival

Question 19

what kind of lights penetrate deeper in water

Answer 19

LED

Question 20

what are the consequences of artificial light

Answer 20

disorientation
altered activity patterns
spawning asynchrony
altered habitat choice
altered interactions

Question 21

what are consequences of sound pollution

Answer 21

• interference
• behavioural changes
• physiological changes

Question 22

what is the 10s rule

Answer 22

1/10th survive introduction

1/10th establish

1/10th become invasive

Question 23

what is discounting

Answer 23

rate at which people value immediate gains over future benefits

Question 24

why do fishermen discount

Answer 24

• alternate sources of ROI (take fish now, money in bank)
• risk that investment may not grow as expected
• risk that someone else may reap benefits

Question 25

what are the types of active gear

Answer 25

purse seine otter trawl beam trawl scallop dredge

Question 26

what are the types of static gear

Answer 26

pot trap pole + line longline

Question 27

what are the types of artisanal fishing techniques

Answer 27

gleaning spears/harpoons blast fishing muri-ami

Question 28

what do fishing effects on populations depend on

Answer 28

gear selectivity species behaviour species life history

Question 29

what characteristics would the perfect marine fish to fish intensely

Answer 29

early maturation mature at large size produce many large offspring long reproductive lifespan

Question 30

what are the population effects of fishing

Answer 30

- decrease in abundance, mean size, mean age -reduction in fecundity -skews sex ratio - reduce age of maturation

Question 31

what are the community effects of fishing

Answer 31

extinctions extrications (species doesn't live here anymore) reduction in diversity changes in community structures changes in size structure (ore small, less large ones) competition and trophic interactions

Question 32

what are the fishing effects on the benthos

Answer 32

bottom contact gear damages it

Question 33

where do they do bottom-contact fishing

Answer 33

where: - fish densities are highest (continental shelf) - no obstruction to gear (flat) - allowed to do so (not in shipping lanes/not near oil rigs)

Question 34

how does dredging affect epifauna

Answer 34

damages it reduced habitat complexity

Question 35

what creatures live in places that are lightly dredged

Answer 35

bryozoans tube worms hydroids

Question 36

what creatures live in places that are highly dredged

Answer 36

hard shelled bivalves, crabs, echindoderm

Question 37

what does bleaching/disease/pollution/predation/ destructive fishing lead to in coral reefs

Answer 37

= decrease in corals = potential algal growth

Question 38

what are the reasons for discard

Answer 38

- limited hold space (discard low value species or smaller (less valuable) target species) - discard of target species with lower quotas

Question 39

what species fishing has a lot of bycatch

Answer 39

shrimp and ground fish

Question 40

how do birds get incidentally caught in fishing

Answer 40

through longlines and gill nets

Question 41

what are incidental shorebird capture reduction incentives

Answer 41

reducing bait loss reducing time spent rebating

Question 42

how are incidental shorebird captures reduced

Answer 42

bird scarring lines funnel to bait frozen bait so sinks faster fishing at night

Question 43

how are reptiles incidentally caught

Answer 43

longlines, gill nets, trawls

Question 44

what are incidental reptile catch reduction incentives

Answer 44

Turtles: damaging snakes: venomous

Question 45

how are incidental reptile captures reduced

Answer 45

trawl excluding devices reduce tow duration

Question 46

how are mammals incidentally caught

Answer 46

longlines, gill nets, trawls

Question 47

what are incidental mammal catch reduction incentives

Answer 47

- bad publicity -damage

Question 48

how are incidental mammal captures reduced

Answer 48

- reduce fishing effort - trawl exclude devices - acoustic pinger - changes in fish practices - bycatch quotas

Question 49

what are the production systems of aquaculture `

Answer 49

extensive systems semi-intensive systems - intensive systems - monoculture polyculture

Question 50

what are issues with shrimp farming

Answer 50

nutrient build up, released into sea or mangroves pollution via chemical treatments intrusion of saltwater into agricultural areas threat to wild shrimp

Question 51

what are issues in salmon fishing

Answer 51

- parastive/pathogen transfer - Atlantic salmon escape (invasive) - impacts the seabed - effects salmon evolution/phenotypes

Question 52

why are greenhouse gases bad

Answer 52

they absorb and emit as radiant heat, causing heat to be retained in lower atmosphere

Question 53

what are consequences of warming

Answer 53

- summer arctic ice extent - sea level rise - change in salinity - affects thermohaline circulation - net increases in temp + lowering salinity = increased stratification

Question 54

what does CO2 emissions do to ocean

Answer 54

decrease pH = decreased saturation state, increased saturation horizon

Question 55

what does increased stratification lead to

Answer 55

1. less oxygen making its way from surface to bottom 2. fewer nutrients being brought up to surface from bottom also can increase eutrophication

Question 56

what are the effects of warming on wind patterns

Answer 56

- shift to increase in height of Hadley cells, would cause global temperatures to be more evenly distributed - prevailing westerlies would likely disappear change in upwellings

Question 57

how does warming affect permafrost

Answer 57

thaws permafrost permafrost thaws lots of Hg in it, it is vulnerable to be released

Question 58

how does climate change affect metabolism

Answer 58

- increase in pp - increase in growth rates - increase in pathogen growth but there are constraints: - thermal tolerance - food availability - oxygen availability

Question 59

how does climate change affect calcification

Answer 59

increasing CO2 in seawater make carbonate ions less available

Question 60

how does climate change affect corals

Answer 60

breakdown of symbiosis between corals and their zooxanthallae with increasing sea water temp