Accuracy of angler‐reported data on steelhead, Oncorhynchus mykiss (Walbaum), harvest in Idaho, USA, was quantified by comparing data recorded on angler harvest permits to the numbers that the same group of anglers reported in an off‐site survey. Anglers could respond to the off‐site survey using mail or Internet; if they did not respond using these methods, they were called on the telephone. A majority of anglers responded through the mail, and the probability of responding by Internet decreased with increasing age of the respondent. The actual number of steelhead harvested did not appear to influence the response type. Anglers in the autumn 2012 survey overreported harvest by 24%, whereas anglers in the spring 2013 survey under‐reported steelhead harvest by 16%. The direction of reporting bias may have been a function of actual harvest, where anglers harvested on average 2.6 times more fish during the spring fishery than the autumn. Reporting bias that is a function of actual harvest can have substantial management and conservation implications because the fishery will be perceived to be performing better at lower harvest rates and worse when harvest rates are higher. Thus, these findings warrant consideration when designing surveys and evaluating management actions.

Potential effects of air exposure and fight times on fish caught and released by anglers have been increasingly studied in recent years, yet little is known about how long anglers actually fight the fish and expose them to air before releasing them. In the present study, air exposure and fight times were measured for anglers catching and releasing fish in popular steelhead Oncorhynchus mykiss fisheries in Idaho, and other relevant factors were also recorded such as fishing gear (fly or nonfly), occurrence of anglers photographing their catch, landing method (with net or by hand), and whether the fish was hooked deeply. A total of 432 steelhead were observed being landed, from which 395 fight times and 251 air exposure times were recorded. The longest interval of air exposure for all steelhead caught and released averaged 28.1 s (95% CI, 25.9–31.3 s), and the vast majority of anglers (88%) held steelhead out of water for less than 60 s. Air exposure was not significantly different by gear type but was estimated to be 1.69 times longer if the angler took a photo of their catch; anglers using flies were 58% more likely to photograph their catch than nonfly anglers. Fight time averaged 130 s (95% CI, 119.3–140.7 s) and differed significantly by gear type, with fly anglers taking an estimated 1.54 times longer to land fish than nonfly anglers. Deep‐hooking rates were 0% for fly and bait and/or jig terminal tackle and 1% for lures. In the context of previous studies that have measured postrelease mortality of caught‐and‐released salmonids, the effects of these fight and air exposure times and deep‐hooking rates in Idaho steelhead fisheries are likely negligible.

In recent years, increased scrutiny has been placed on the physiological effects of exhaustive exercise and air exposure on caught‐and‐released fish. Steelhead Oncorhynchus mykiss broodstock in the South Fork Clearwater River, Idaho, were collected by anglers during a winter fishery (water temperatures of 2–5°C); this enabled fight and air exposure times to be recorded to determine their influence on prespawn survival and progeny survival to the fry stage in the hatchery. The average fight time during angling was 164 s. Air exposure was measured when anglers landed fish and again during fish transport from the river to the hatchery vehicle; the longest interval of air exposure averaged 23 s during angling and 28 s during transport. Three‐year average prespawn survival was 97.0% for 1,148 angler‐caught fish, compared to 91.9% for 3,325 swim‐in broodstock collected at the hatchery. The top mixed‐effects logistic regression model estimated that the odds of progeny survival increased by 1.027 times with each additional day of the year until an adult fish spawned; this was likely a reflection of peak spawn time in the hatchery. Fight time and air exposure time did not influence progeny survival or prespawn mortality of adult steelhead captured by anglers.