Ichthyoplankton Indicators for the Pacific Northwest

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Ichthyoplankton Indicators for the Pacific
Northwest

• Ric Brodeur, Bob Emmett, Bill Peterson
• NOAA/NMFS/NWFSC, Newport OR
• George Boehlert
• HMSC, OSU, Newport
• With substantial contributions from
• Toby Auth, Maria Parnel and Stacy Remple (OSU)

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Why we study Ichthyoplankton

• Survival of larvae may directly influence future
  abundances of adult fish stocks
• The distribution and abundance of fish eggs and
  larvae can provide clues to the spawning
  locations, success, and environmental
  requirements of important fish species
• Ichthyoplankton can represent a vital link in
  the food chain between smaller planktonic and
  larger piscivorous organisms

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NWFSC Ichthyoplankton Research
The Fish Ecology Division has recently begun
several projects to study species composition,
diversity, abundance, and distribution of
ichthyoplankton in the Pacific Ocean from San
Francisco Bay to northern Washington. We are
analyzing distributions in relation to various
spatial (latitudinal, cross-shelf, depth in water
column), temporal (year, season, diel), and
environmental (temperature, salinity, biological
community structure) variables.
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Historical Sampling of NCC

• Early cruises on extended CalCOFI grid

• Extensive sampling by Sally Richardson and Bill
  Pearcy in the late 1960s and 1970s off Newport
  and Oregon and Washington coasts

• Special studies during 1983 El Nino

• Cooperative US-Soviet surveys in 1980s over
  broad geographic area (Doyle et al.)

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NortheastPacific andCalifornia Current
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Recent Ichthyoplankton Studies
1) NMFS Ichthyoplankton Sampling (1994-98)
2) GLOBEC Mesoscale and LTOP Surveys (2000 and
2002)
3) Newport Line sampling (1996-present)
4) Columbia River plume studies (1999-present)
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NMFS Ichthyoplankton Sampling 1994-98
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Historical Distribution
(Emmett et al. 2005)
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Historical Distribution
(Emmett et al. 2005)
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Historical Distribution
Anchovy Egg Distribution off Oregon and Washington
(Richardson 1981)
(Emmett et al.1997)
1976 Estimated Anchovy Spawning Biomass gt
200,000 MT
1995 Estimated Anchovy Spawning Biomass lt 50,000
MT
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GLOBEC Ichthyoplankton
Fish larvae were collected at 5 stations (5-45
nautical miles offshore) along a single,
historically-sampled transect (NH line) off
Newport, Oregon from April to September in 2000
and 2002.
A 333-µm mesh, 1-m2 mouth-opening MOCNESS
(Multiple Opening/Closing Net and Environmental
Sensing System) was used to collect samples at
3-9 discrete depths, and record temperature and
salinity throughout the water column.
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GLOBEC Ichthyoplankton
Dominant Taxa Collected in All Samples
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GLOBEC Ichthyoplankton
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GLOBEC Ichthyoplankton

• Error bars represent Standard Errors
• Different letters within taxa represent
  significant (plt 0.05) difference between stations

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GLOBEC Ichthyoplankton
Dominant larval taxa from the Newport line in
2000 and 2002.
Sardinops sagax
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GLOBEC Ichthyoplankton
Species Assemblages
1
2
3
4
5
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GLOBEC Ichthyoplankton

• Error bars represent Standard Errors
• Different letters within taxa represent
  significant (plt 0.05) difference between stations

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GLOBEC Ichthyoplankton
2356
0330
0630
1623
Lyopsetta exilis
Sebastes spp.
Depth (m)
Stenobrachius leucopsarus
Tarletonbeania crenularis
Proportion of total abundance
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GLOBEC Ichthyoplankton
Station Groupings
Station
NH5 9 km NH15 28 km
(km from shore)
800
600
400
200
0
Ranked Similarities
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FATE IchthyoplanktonNewport Line Long-term Study

• NH-Line Zooplankton
• Time Series

• Bi-weekly Sampling
• 1972 1973 (Miller, Pearcy, Peterson)
• 1977 1978 (Richardson, Laroche)
• 1983 (Miller, Brodeur)
• 1996 2004 (Peterson et al.)

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FATE Ichthyoplankton
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(No Transcript)
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FATE IchthyoplanktonNewport Line Long-term Study
Dominant Taxa Collected in 2004
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FATE IchthyoplanktonNewport Line Long-term Study
Dominant Taxa Collected in 2005 (Incomplete)
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FATE Ichthyoplankton
No Data
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FATE IchthyoplanktonColumbia River Plume Studies

• Sampling
• Two stations off Columbia River (11 and 16 miles
  from shore)
• Plankton samples collected approximately every 10
  days April-July
• 1-M net (round net with 1-M diameter)
• Oblique tow down to 60 m
• Daytime sampling
• CTD cast at each station
• Physical Parameters
• Temperature
• Salinity
• Chlorophyll concentration
• Columbia River outflow
• Winds at buoys

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FATE IchthyoplanktonColumbia River Plume Studies
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FATE IchthyoplanktonColumbia River Plume Studies
Sampling by Year and Month
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FATE IchthyoplanktonColumbia River Plume Studies
Dominant Taxa Collected in All Samples
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FATE IchthyoplanktonColumbia River Plume Studies
Seasonal and Interannual Variation in Anchovy Eggs
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FATE IchthyoplanktonColumbia River Plume Studies
Interannual and Seasonal Variation in Top Five
Species
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FATE IchthyoplanktonColumbia River Plume Studies
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FATE IchthyoplanktonColumbia River Plume Studies
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Goals for the Coming Year

• Examine long-term changes in ichthyoplankton
• abundance in relation to climate change

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FATE IchthyoplanktonColumbia River Plume Studies
Time Series of Environmental Conditions (adapted
from Hooff and Peterson, MS)
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Goals for the Coming Year

• Examine long-term changes in ichthyoplankton
• abundance in relation to climate change

• Relate changes in abundance of early life
  stages to adult spawners and subsequent year
  class strength

• Develop indices of coastal conditions related
• to the survival of early life stages

• Provide managers early indications of strong
• year classes that may recruit into fisheries