Marine Food Chains/Webs

1
Marine Food Chains/Webs

• Energy from primary production is transferred up
  the trophic chain
• Each step is inefficient (90 energy is lost)
• Shorter chains are more efficient at producing
  apex predators

2
Bottom Up Control on the Marine Food Webs
hn
CO2
O2
Phytoplankton
Food Web
Plants
NUTS
Primary Secondary Production
Production
3
(No Transcript)
4
(No Transcript)
5
Marine Food Chains/Webs

• Energy from primary production is transferred up
  the trophic chain
• Each step is inefficient (90 energy is lost)
• Shorter chains are more efficient at producing
  apex predators

6
Primary Production by Biome
Ryther (1969) Science
7
(No Transcript)
8
Primary Production by Biome
Ryther (1969) Science
9
Marine Food Chains/Webs

• Open ocean 90 area most of the NPP but
  little fish production
• Coastal ocean 9.9 area 20 of the global NPP
  but ½ of the fish production
• Upwelling systems 0.1 area little NPP but ½
  fish production

10
(No Transcript)
11
(No Transcript)
12
CalCoFI Zooplankton Sampling
13
CalCoFIZooplankton
Dudley Chelton OSU
14
Seasonal Zooplankton
Zoo Winds
15
Seasonal Zooplankton
Zoo Winds
16
CalCoFI Zooplankton
Highest in the tongue of CA Current
17
The Upwelling Conveyor Belt
High Zoo
Low Zoo
Lower Zoo
High Chl
Low Chl
Lower Chl
High NUTS
Low NUTS
Sinking POM
Highest NUTS
18
CalCoFI Zooplankton
Corresponds to low salinity waters from north
19
CalCoFI Zooplankton
Highest in the tongue of CA Current
20
The Upwelling Conveyor Belt
High Zoo
Low Zoo
Lower Zoo
High Chl
Low Chl
Lower Chl
High NUTS
Low NUTS
Sinking POM
Highest NUTS
21
CalCoFIZooplankton
Hi Zoos Low Temp ENSO connection All in
pre-1977
22
CalCoFI Zooplankton
70 Decline in 1970s
23
The 1977 Regime Shift
McGowan et al, 1998 Climate-Ocean Variability
and Ecosystem Response in the Northeast Pacific,
Science
24
Cool vs. WarmWater Species
T. Spinifera cool water N. Simplex warm
25
Cool water species gone during ENSO
26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
(No Transcript)
30
Zooplankton in CA Current

• Zooplankton follow climatic changes both ENSO and
  PDO are seen
• Long term zoo distribution consistent with
  upwelling conveyor advection from N Pac
• Evidence of species switching is also observed