Trawl Catch and Species Abundance from the 2019 Gulf of Alaska International Year of the Salmon Expedition

Study Extent

A total of 64 tows were conducted throughout the Gulf of Alaska between February 19 and March 16 as part of the International Year of the Salmon High Seas Expedition.

Sampling

To further improve the understanding of factors impacting salmon marine winter survival, a total of 64 midwater trawls were conducted (trawl opening ~ 30 x 40 meter). Total species-specific catch numbers and weight were recorded. Taxa were identified to the lowest taxonomic rank possible. For some species the individual biometrics were recorded, such as length (fork, total, standard, mantle or bell diameter), wet weight, sex, and maturation stage. In addition, DNA samples, otoliths, muscle tissue, scales and live/gonad data of salmonids were collected for further analysis in Alaskan and UBC labs. The data collected from the trawls aim to improve our understanding of the food web structure.

Method steps

1. Taxonomic records were identified to the lowest taxonomic rank possible. Additionally, for some species some individual biometrics were recorded, such as (fork, total, standard and/or mantle) length, weight, sex and age class. Furthermore for salmonids, DNA samples, otoliths, muscle tissue, scales and liver/gonad data were collected for further analysis in Alaskan and UBC labs.

Gulf of Alaska