nearshore fish in the chukchi sea, alaska€¦ · nnearshore fish in the chukchi sea,...
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Nearshore Fish in the Chukchi Sea, AlaskaNearshore Fish in the Chukchi Sea, Alaska Objectives
In nearshore waters of the Chukchi Sea: • Identify distribution and relative abundance of fi sh Establish• baseline for long-term Arctic monitoring Collect and archive fi sh for energetic, genetic, and • voucher specimens
Sample designAugust 2007- 2009 &
6 stations
2 bottom trawl tows &
Methods
Bottom trawl towsBeach seine hauls
Environmental conditions
Capelin
Sea ice break-up
Timing of ice break-up varied among years•
June 2007 August 2008 July 2009
Barrow Sea Ice Cam images
Arctic cod
Dominant fish
earlyearly latelate moderatemoderate
2008
Species composition & catch
Seine
Trawl
2007 2009
n = 98 n = 1,465 n = 246
Arctic cod
Arctic cod
other spp.
Sculpins Sculpinsother spp.
n = 5,779 n = 415 n = 2,387
CapelinCapelin
other spp.
Sand lanceSculpins
coldcoldwarmwarm
Sea surface temperature (SST)
• Mean annual August SST related to ice break-up timing
oC-2 0 642 8 10 12 14
AOOS imagesAOOS images
20072007studyarea
warmwarmx x == 9 9°°
2009
moderate moderatex = 6°°
o
==
20082008
coldcoldx x == 2 2°°
Pacifi c sand lance
Sculpin spp.
Results
n = 98 n = 1,465 n = 246
Arctic cod
Arctic cod
other spp.
Sculpins Sculpinsother spp.
n = 5,779 n = 415
n = 1,412
CapelinCapelin
other spp.
Sand lanceSculpins
Sept. 2009moderatemoderate
Capelin
Arctic cod
n = 6,449
• Capelin most abundant in warm year (2007) and in September• Arctic cod most abundant in cold year (2008) and in September• Catch and species composition differed in 2009 between Aug. and Sept.
moderatemoderate
Saffron cod
September 2009
1 seine haul/station
Slender eelblenny
Beaufort Sea
Chukchi SeaBarrow
Cooper Island
Arctic cod
Seine
Other spp. 18%
Capelin 82%
Trawl
Catch by gear
• Dominant speciesdiffered by gear type
Capelin
other spp.
Beachseine
8 m depthtrawl
trawl5 m depth
Alaska
0 15 km105
represent the views or offi cial position of the Department of Commerece, NOAA, or NMFS. The recommendations and general content presented in this poster do not necessarily
Total catch
% T
otal
cat
ch
Arctic cod
Capelin
26 species
n = 19,147 fi sh
10%
21%
69%
Annual catch
• Abundance varied by
TrawlSeine
2008 - cold2007 - warm
2009 - moderate
Chukchi Sea
year and gear type
John F. Thedinga, Scott W. Johnson, and A. Darcie NeffNOAA Fisheries, Auke Bay Laboratories, Juneau, Alaska
Chris A. Hoffman U.S. Army Corps of Engineers, Alaska District
• Capelin and Arctic cod are abundant in nearshore waters of the Chukchi Sea • Sea ice conditions affect the distribution and abundance of nearshore fi sh Fish abundance and species composition varied monthly and annually•
ConclusionsConclusions Mostly juveniles
Other spp. 44%
Arctic cod 56%
Gulf of Alaska
Bering Sea
Arctic Ocean
Studyarea