Lower Skeena River Coho Indicators Program

Since 2014, the Zymachord River Coho CWT Harvest Distribution project has produced 20,000 marked Coho salmon fry annually. Each year, Northern Funds have been graciously received for the purchase of coded-wire tags (CWTs) . In cooperation with volunteers of the Northwest Watershed Enhancement Society (NWES) broodstock has been collected and reared at the Eby Street hatchery in Terrace, BC. In the spring upon smolting CWTs have been applied, adipose fin clips removed, and the coho have been released into the Zymachord River. True to its proposed intent this pilot project has successfully fulfilled all of its objectives including the determination of harvest patterns of Zymachord coho in Alaskan and Canadian fisheries. The collection of broodstock, incubation of eggs, over-winter rearing and feeding of fry, and the clipping and releasing of smolts has been expertly conducted each without any issue; Its CWTs have been encountered in the primary Alaskan and Canadian fisheries; Total tag encounters have been estimated in all fisheries and within its escapement in a consistent manner; Zymachord River CWT encounter results have been compared to the Deena River Coho (Haida Gwaii 2E), Zolzap River Coho (Area 3 Lower Nass), and Toboggan Creek Coho (Area 4 Upper Skeena).

What is being proposed (in addition to the continuance of CWT purchasing) is a Zymachord mark and recapture program and peak helicopter surveys of indicator streams (Zymachord, Extew, Exchamsiks, and Kasiks Rivers). With support from First Nations, Fishery Representatives, and DFO the information gathered will be used to determine status and co-variation of Lower Skeena Coho populations. In addition to fishery encounters of Zymachord CWTs, escapements will be determined for the Lower Skeena wild stock extensive indicators, an accurate escapement of known accuracy will be determined for the Zymachord hatchery stock intensive indicator as well as estimates of survival and fishing exploitations.

Coho cwt and exploitation indicators play an important role in our understanding and management of coho in the northern boundary area. The “lower” Skeena coho have a distinctly different timing (mid-September) compared to the middle and upper Skeena coho (August 5th). There is considerable information from previous middle and upper Skeena coho cwt programs (Babine, Toboggan, Slamgeese and Kitwanga) but there have been no previous cwt programs for the lower river late timed stocks. It is assumed that the lower Skeena stocks have similar distribution and harvest impacts as the former Lachmach (outside Area 3) and current Zolzap (lower Nass River tributary).

N19-I46 Lower Skeena River Coho Indicators Program 2019 Report