Reconstruction of walleye exploitation based on angler diary records and a model of predicted catches

Abstract

The walleye population in Canadarago Lake, New York, was 81-95% exploited in the 1988 fishing season, the year in which a previous restriction on the length and number of legally harvestable fish was liberalized. Using diary records from a subset of fishermen, growth estimates, and an estimate of the walleye population in the following year, a method is developed to reconstruct the fish population back to the spring of 1988 and thus determine the exploitation rate. The method is based on a model of diary catches that partitions time and fish length into a set of cells and relates predicted catches and population sizes in these cells. The method's sensitivity to the partitioning scheme, the growth estimates, and the diary data is analyzed. The method could be employed in other fish exploitation analyses and demonstrates the use of inexpensive angler-collected data in fisheries management.

Effects of Harvest, Natural Mortality, and Escapement on Reservoir Walleye Populations

“…Big Creek Lake is located adjacent to the largest metropolitan area in Iowa (<24 km from Des Moines metropolitan area, approximately 700,000 people) and receives considerable fishing pressure (Dodd and Otting 2012). Although Big Creek exploitation estimates are above average, estimates up to 68% have been reported for other Midwest reservoirs (Quist et al 2010) and up to 94% in Canadarago Lake, New York, USA (Willms and Green 2007). Spatiotemporal variation in harvest mortality further illustrates the importance of understanding the effects of anglers and other sources of fish loss on Walleye populations, as a thorough understanding and quantification of fish loss is imperative when devising management plans.…”

Analysis of Compensatory Responses in Land‐Locked Alewives to Walleye Predation: A Tale of Two Lakes

“…Similar mortality rates (34.6% per year) were obtained from the gill-net catch curves, using the sum of all fish of ages 3-9 caught from 1995 to 2008. These mortality rates indicate an exploited population; walleyes are often targeted by anglers in Canadarago Lake (Willms and Green 2007).…”

Understanding factors regulating Muskellunge and Walleye reservoir populations using radio telemetry

“…summarized Walleye exploitation for 46 populations with a median exploitation rate of 21% and only four populations with a mean over 30%. Although Big Creek exploitation estimates are above average, estimates up to 68% have been reported for other Midwest reservoirs (Quist et al 2010) and up to 94% in Canadarago Lake, New York, USA (Willms and Green 2007). Spatiotemporal variation in harvest mortality further illustrates the importance of understanding the effects of anglers and other sources of fish loss on Walleye populations, as a thorough understanding and quantification of fish loss is imperative when devising management plans.…”

“…American Fisheries Society, Southern Division, Reservoir Committee, Bethesda, Maryland. Willms, A. R. and D. M. Green. 2007.…”

“…Escapement, the permanent emigration of stocked fishes from a system, can contribute to fish loss from stocked populations and has been observed for Muskellunge as well as Walleye . Additionally, while harvest of Muskellunge is minimal , Walleye are a popular food fish and experience significant exploitation in many systems Willms and Green 2007;Quist et al 2010). Finally, little is known about natural mortality rates for Muskellunge and Walleye; however, it may be significant in regulating reservoir populations, particularly towards the southern edge of their range.…”