Vertical Patterns and Temporal Trends

Question 1

How vertical profiles influence zoop abundance

Answer 1

Food availability, PPs and how they are affected by light, stratification and nutrients
Food quality and type.
Biological interactions, pred-prey and pred type
Physiological constraints, oxygen.

Question 2

Species abundance with depth

Answer 2

80+% of depth integrated abundance is in the food rich upper 200m.
Total species number greatest in epipelagic (0-200m) to mesopelagic (500-1000m)

Question 3

Diversity with depth

Answer 3

Functional diversity, how they feed/role highest at surface

Question 4

Tides and salinity effect

Answer 4

Osmoconformers or osmoregulators
Wide range, euryhaline, narrow stenohaline
Utilise behaviour (D-TVM) to maintain position within estuary.

Question 5

DVM

Answer 5

Balances trade off between predation risk and energy gain at food-rich surface
Visual predators inhibited
Temperature-benefit hypothesis, metabolic gains in cold temp at depth

Question 6

DVM How:

Answer 6

Controlled by light
Stay in preferred isolume or respond to rate of change of light
Deep migrating organisms use internal cues, endogenous rhythms, clock genes.
Hierarchical response to primary causal factors (light) and secondary causal factors (preds, food, oxygen)

Question 7

DVM sp difference

Answer 7

Distances covered by epi and mesopelagic sp vary from 10s to 100s m
Preferred depth range varies with life stage, season, latitude, water conditions

Question 8

DVM, Chile with an OMZ

Answer 8

Most taxa aggregate above oxycline, espiecially if intense
Several taxa closely associated with OMZ, able to perform DVM into core of OMZ

Question 9

Temporal trends of distribution

Answer 9

LT climate related trends w/in Atlantic
Effects of climate variability in N Sea
Seasonality and the drivers of patterns: species succession, reproduction, vertical migration.

Question 10

Calanus finmarchicus, C. helogolandicus

Answer 10

Changes in mean decadal abundance used
Cf, Cold water species
Ch, warm water species
Indicators of the NAO and LT climate change
Warmer species, smaller, less biomass, lower oil content and less nutritious

Question 11

Jellyfish and NAO

Answer 11

High NAOI, high SST, strong Wly winds and wavy, rare A. aurita
Low NAOI, low SST, weak ww, abundant aurita
Jellies predate zoop.

Question 12

Plankton dynamics in temperate seas

Answer 12

Phase 1, initial dev of spring phyto bloom
Phase 2, demise of phyto bloom
Phase 3, mid-summer recycling phase
Phase 4, regenerative period

Question 13

Seasonal contribution of copepods

Answer 13

Copepods are 80-90% of total zoop
Reproduction and species sucession main drivers of seasonal trends in total mesozoop abundance and biomass

Question 14

Multiple gens per year in C. finmarchius

Answer 14

In temperate, 3 generations per year
As temp changes and food decreases through season, generation time decreases and adult size increases.
In colder, dev slower and begins later
Adopt an overwintering strat, diapause at depth.
Temp and food key parameters influencing growth and breeding

Question 15

Arctic species and sea ice cover/temp

Answer 15

Arctic species take 2-3 years to complete their whole life cycle

Question 16

Seasonal succession of copepod sp

Answer 16

Peak zoop abundane in summer, seasonal reproduction of a succession of copepods.