Behavior and Survival of Wild and Hatchery‐Origin Winter Steelhead Spawners Caught and Released in a Recreational Fishery

Abstract

Mandatory catch and release of wild fish and supplementation with hatchery-reared fish are commonly used to sustain sport fisheries on low-abundance populations of wild steelhead. However, their effectiveness in limiting angling mortality on wild fish is uncertain. We radiotagged 226 (125 wild, 101 hatchery) angled adult steelhead Oncorhynchus mykiss near the mouth of the VedderϪChilliwack River, British Columbia, in 1999 and 2000 and monitored their subsequent movements to determine survival to spawning and overlap in the distributions of inferred holding sites, spawning sites, and spawning times. The distributions of prespawning holding sites did not differ between wild and hatchery fish in either year, but spawning locations differed. Holding and spawning sites used by hatchery fish were restricted to the lower two-thirds of the river, downstream of the hatchery where they were reared but well upstream of their smolt release site. Wild fish spawned throughout the watershed. Spawning times did not differ between wild and hatchery fish, but varied with run timing. The maximum mortality from the initial catch and release and radio-tagging was 1.4% in 1999 and 5.8% in 2000; true mortality rates were lower because tag regurgitation was indistinguishable from death. The fishery subsequently killed 2.5% of tagged wild fish and harvested 20% (1999) and 43% (2000) of the hatchery fish. Seventy-two tagged fish were recaptured and released in the sport fishery up to three times without any mortality before spawning. Hatchery fish were recaptured at twice the rate of wild fish. At least 92% of unharvested fish spawned, and 75% of successful spawners survived to emigrate from the watershed. The incidence of postspawning death did not vary with the frequency of capture and release. Catch-and-release angling imposed small costs in terms of survival; however, behavioral differences existed between adult wild fish and the adult F 1 progeny of wild fish reared to smolt stage in a hatchery.

Distribution and Movement of Steelhead and Anglers in the Clearwater River, Idaho

“…Nelson et al. () used radiotelemetry to describe the distribution of prespawning wild and hatchery steelhead in the Vedder–Chilliwack River, British Columbia. They found considerable overlap in the spatial distributions of wild and hatchery steelhead.…”

“…; Dittman and Quinn ; Nelson et al. ). Also, the amount of time that hatchery smolts spend in the river prior to emigrating to the ocean influences their ability to home to their release site (Keefer and Caudill ).…”

“…Information on the spatial and temporal distributions of wild and hatchery steelhead and anglers may influence management decisions that direct angling effort towards hatchery fish and away from wild fish that are of conservation concern (Johnson and Kucera ; Nelson et al. ). Such data may also provide insight as to how the location of juvenile release may influence the distribution and final fates of hatchery steelhead in the Clearwater River.…”

Resilience of Pink Salmon and Chum Salmon to Simulated Fisheries Capture Stress Incurred upon Arrival at Spawning Grounds

“…Pacific salmon captured and released in the ocean have been shown to experience much higher postcapture and release mortality rates: 33-55% for purse-seine-caught Sockeye Salmon , 44% for troll-caught Coho Salmon (Parker et al 1959), and up to 75% for Coho Salmon captured by gill net (Buchanan et al 2002). During river migration, most studies of capture mortality have focused on recreational angling, with mortality estimates ranging from 1% to 69% depending on species, study location, duration of postrelease monitoring, and research techniques (Bendock and Alexandersdottir 1993;Vincent-Lang et al 1993;Vander Haegen et al 2004;Nelson et al 2005;Cowen et al 2007;Raby et al 2012). Recent biotelemetry research revealed that angled and released Sockeye Salmon migrating up the lower Fraser River were 20-35% less likely to reach spawning areas than individuals tagged in the ocean and subsequently tracked in freshwater (Donaldson et al 2011, in press).…”

Post‐release and pre‐spawning behaviour of simulated escaped adult rainbow trout Oncorhynhus mykiss in Lake Övre Fryken, Sweden

“…The fate of this latter group is unknown. Fishing by gillnets or hand‐held gear greatly influences rates of mortality for released farmed salmonids (Nelson et al , 2005; Baird et al , 2006), thus the fishing mortality recorded in the present study was probably an underestimate.…”