Nearshore fish in the Chukchi Sea, Alaska · PDF file NNearshore Fish in the Chukchi Sea, Alaskaearshore Fish in the Chukchi Sea, Alaska Objectives In nearshore waters of the Chukchi

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 design August 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

Capelin Capelin

other spp.

Sand lanceSculpins

coldcoldwar m

war m

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

20072007 study area

warmwarm x x == 9 9°°

2009

moderate moderate x = 6°°

o

==

20082008

coldcold x 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

Capelin Capelin

other spp.

Sand lanceSculpins

Sept. 2009mod erat

e mod

erat e

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.

mod erat

e mod

erat e

Saffron cod

September 2009

1 seine haul/station

Slender eelblenny

Beaufort Sea

Chukchi Sea Barrow

Cooper Island

Arctic cod

Seine

Other spp. 18%

Capelin 82%

Trawl

Catch by gear

• Dominant species differed by gear type

Capelin

other spp.

Beach seine

8 m depth trawl

trawl 5 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

ot al

c at

ch

Arctic cod

Capelin

26 species

n = 19,147 fi sh

10%

21%

69%

Annual catch

• Abundance varied by

Trawl Seine

2008 - cold 2007 - warm

2009 - moderate

Chukchi Sea

year and gear type

John F. Thedinga, Scott W. Johnson, and A. Darcie Neff NOAA 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

Study area