COOK INLET STUDIES

Projects INFO

Escapement of Kenai River Chinook Salmon has fallen below the lower permissible limit. This has led to severe restrictions and closures of the eastside setnet (ESSN) sockeye fishery in Cook Inlet, Alaska which intercepts Chinook as bycatch. Kintama has been working with ADFG to improve our understanding of the relative migration depths of returning adult sockeye and Chinook salmon, and the effective fishing depths of the setnets through the tidal cycle.

We have created three web-based net animations to illustrate the behaviour of fishing nets used in our Cook Inlet studies. The two animations for the 2023 study use equations to determine the net positions. The “physics-based” net animator solves Newton’s equations of motion for a system that has the approximate weight, buoyancy, and dimensions of the offshore nets in the study. The “kinematic” animator positions the moorings and buoys by directly specifying their positions as functions of time. They are intended only for illustration and are not constrained by the observed depth data. The 2015 animator determines the net motions directly from depth sensors attached to the nets, which are portrayed as rigid bodies.

We also provide a link to our dynamic animation of acoustic-tagged Chinook and sockeye as they migrate over a telemetry grid offshore and through the ESSN fishery area and into the Kasilof and Kenai rivers. Have a look at the pre-defined display options available under the Case menu.

Access the 2023 physics-based animation here.

Access the 2023 kinematic animation here.

Access the 2015 animation here.

Animation for 26 adult Chinook and 51 adult sockeye that were acoustic-tagged and released in Cook Inlet in 2013. Access the animation here.


Physics-based animation of effective setnet fishing depths 2023


Kinematic animation of effective setnet fishing depths 2023


Animation of effective setnet fishing depths 2015


Animation of Chinook and sockeye tagged in 2013