Stock assessment of arctic grayling in the Salcha, Chatanika, and Goodpaster rivers during 1993
By: by Stafford M. Roach.
Contributors: Alaska. Division of Sport Fish.
Series: Fishery data series -- no. 94-13.
Publisher: Alaska Dept. of Fish and Game, Division of Sport Fish
Published: 1994
Place of publication: Anchorage, Alaska
Language: eng
Number of pages: 109
Subjects: Arctic grayling -- Alaska -- Salcha River.; Arctic grayling -- Alaska -- Chatanika River.; Arctic grayling -- Alaska -- Goodpaster River.; Fish populations -- Alaska -- Salcha River.; Fish populations -- Alaska -- Chatanika River.; Fish populations -- Alaska -- Goodpaster River.
Description: Abundances and stock compositions of Arctic grayling Thymallus arcticus were estimated for portions of the Salcha, Chatanika, and Goodpaster rivers in 1993 using single-sample mark-recapture experiments. The Salcha River study area was from river kilometer 40 downstream to the Richardson Highway Bridge (river kilometer 3.2); the Chatanika River study area extended from 5 kilometes above the Elliott Highway Bridge downstream to approximately 24 kilometers above the Murphy Dome Road extension; and, the Goodpaster River study area was from river kilometer 52.3 downstream to river kilometer 2.7. Estimated abundance of Arctic grayling  150 millimeters fork length for the Salcha River study area was 15,950 fish (SE = 2,442) and for the Goodpaster River study area 10,841 fish (SE = 1,340). Estimated abundance of Arctic grayling  150 millimeters fork length for the Chatanika River study area was 11,766 fish (SE = 1,273) and for Arctic grayling  189 millimeters fork length was 9,506 fish (SE = 971; both estimates are given for the Chatanika River because there were no recaptures below 189 millimeters fork length). Estimated densities of Arctic grayling  150 millimeters fork length within the Salcha River study area was 433 fish per kilometer. Estimated densities, however, varied between sections of the Salcha River study area (365 fish per kilometer in the upper section and 493 fish per kilometer in the lower section). Estimated densities of Arctic grayling  150 millimeters fork length within the Chatanika River study area was 150 fish per kilometer. Estimated densities, however, varied between sections of the Chatanika River study area (252 fish per kilometer in the upper section and 89 fish per kilometer in the lower section). Densities of Arctic grayling  150 millimeters fork length in the Goodpaster River were similar throughout the study area (217 fish per kilometer). The proportion of age-3 fish were: 0.47 (SE = 0.02) in the Salcha River study area; 0.21 (SE = 0.02) in the Chatanika River study area, and; 0.45 (SE = 0.02) in the Goodpaster River study area. The proportion of Arctic grayling from 150 to 270 millimeters fork length within the Salcha River study area was 0.81 (SE = 0.01), within the Chatanika River study area 0.51 (SE = 0.03), and within the Goodpaster River study area 0.91 (SE = 0.01). For comparison of abundance between years: abundance of Arctic grayling ^ 200 millimeters fork length within the Salcha River study area was 7,706 fish (SE = 2,555) in 1992 and 8,927 fish (SE = 1,518) in 1993; abundance of Arctic grayling  150 millimeters fork length within a similar section of the Chatanika River (from above the Elliott Highway Bridge downstream approximately 64 kilometers) was 11,712 fish (SE = 1,429) in 1992 and 10,315 fish (SE = 1,251) in 1993; and, abundance of Arctic grayling  150 millimeters fork length within the Goodpaster River study area was 6,886 fish (SE = 809) in 1992 and 10,841 fish (SE = 1340) in 1993.
Notes: "August 1994."

"Partially financed by the Federal Aid in Sport Fish Restoration Act ... under project F-10-9, job nos. R-3-2(a) and R-3-2(e)."

Includes bibliographical references (p. 48-54).

Also issued online.