Week 5: Invertebrates 1

Question 1

Why are multi year mesozooplankton samples useful indicators of ocean changes

Answer 1

1. Abundant
2. They Amplify hydroclimatological signals
3. Short life cycles (so they are responsive to quick term changes)
4. Few zooplankton are fished (responses are due to exclusively environmental change)

Question 2

Meszooplankton samples over greater than ____ years

Answer 2

20

Question 3

Long term mesoplankton samples are most useful when they span

Answer 3

Several oceanographic oscillations or cycles

Question 4

Long term time series needed as they are so

Answer 4

Variable

Question 5

PDO

Answer 5

Pacific Decedal Oscillation

Question 6

PDO is defined by

Answer 6

Sea surface temperature (SST) anomalies in the north pacific basin

Question 7

PDO affects the region by changing

Answer 7

Temperatures and stratification

Question 8

The positive PDO phase =

Answer 8

Warmer along the wst coast of USA and vice versa

Question 9

Biomass of zooplankton reduced by what percentage from 1951-1995

Answer 9

80-95%

Question 10

Loss of biomass of zooplankton resulting from

Answer 10

Sea surface warming, resulting in stratification of new species and reducing surface nutrients

Question 11

Zooplankton changes in response to the PDO in warm phase

Answer 11

1. Reduced zooplankton biomass
2. Loss of colder zooplanlton species

Question 12

Ecosystem changes due to PDO warm phase

Answer 12

1. Crucial fish sepcies who rely on zooplankton had reduced survival
2. 1 degree production reduced
3. Vertical stratification increased and upwelling decreased
4. El nino drives shorter term reductions in productivity for the same reasons

Question 13

Continuous plankton recorders

Answer 13

1. Towed near surface
2. Zooplankton caught on drum of silk
3. Run from 1931
4. To date 5 million sampled

Question 14

NAO

Answer 14

North Atlantic Oscillation

Question 15

NAO results from

Answer 15

Difference in pressure between the azores high and the icelandic flow

Question 16

Nao controls

Answer 16

The strength and direction of the westerly winds

Question 17

Oscillation periodicity is

Answer 17

Unpredictable

Question 18

Positive NAO results in

Answer 18

1. Warmer, less saline USA coastline
2. Cooler sea temperatures along Canadian/greenland coasts

Question 19

Changes in zooplankton in the north atlantic is altering

Answer 19

Carbon export

Question 20

Three key zooplankton mechanisms that involve carbon export

Answer 20

1. Biological gravitational pump = fecal pellets
2. Diel vertical migrations
3. Seasonal vertical migrations

Question 21

The north atlantic has warmed by ___ degrees over the past 100 years

Answer 21

0.6-0.8

Question 22

How have we recorded changes in zooplankton abundance and composition in response to increased sea temperatures

Answer 22

Long term plankton sampling

Question 23

In the North Atlantic, smaller warm species of zooplankton are being replaced by

Answer 23

Larger cold species

Question 24

Altering carbon export rates due to

Answer 24

Reduced biomass and distributional changes

Question 25

In meroplankton, benthic species have ____ stage

Answer 25

Planktonic larval stage

Question 26

Warming of the east australian current (EAC) has resulted in

Answer 26

1. EAC strengthened
2. 350km poleward advance over the past 60 years

Question 27

Long term oceanographic oscillations influence zooplankton abundance through

Answer 27

Changing 1 degree productivity rates

Question 28

Three main oceanographic oscillations

Answer 28

PDO, NAO, shorter term El Nino cycles

Question 29

How does directional climate change warming of the ocean affect zooplankton communities

Answer 29

Regime shifts (abundance, composition, phenology and distribution)

Question 30

Regime shifts in zooplankton impact processes in

Answer 30

Carbon export

Question 31

To study for:
* (Essay) How can oceanographic oscillations effect
zooplankton populations (i.e. PDO, NAO, El Nino). Give
examples.
* (Short Answer) Give an example of how changes in
meroplankton can drive population changes

Answer 31

:)