Exploited Size Range

Issued on 13th April 2018

Fishing is a popular sport for a large number of outdoor enthusiasts, ie around 692,052 people in 2017 (MFFP, 2018). This activity is a real economic driver for Quebec and its regions. According to a study published in 2014, Quebec fishermen would spend $ 359.13 million annually on goods and services to fish for walleye only (Écoressource, 2014). With such a large number of sport fishing enthusiasts, it is necessary to introduce management methods conducive to sustainable and quality fishing. Among the modalities that are part of the toolkit of wildlife managers, there is the range of sizes exploited. This modality aims to protect both juveniles and individuals of reproductive age: the broodstock. The size range exploited 32-47 centimeters was installed at the Gouin Reservoir in 2016. This new regulation raised, on the one hand the questioning among the fishermen, and on the other hand, required the adoption of new practices related to the fishing, especially in terms of threading and transport. This regulatory modality is necessary when the abundance of mature females is low and the biomass of females is considered unsatisfactory to ensure recruitment sufficient to maintain a population exploited by sport fishing.

It is important to know that the biomass of a female is a guarantee of quality and quantity for the eggs produced. The choice of size range exploited: The choice of size range exploited for walleye populations is based on the growth of individuals. At the Gouin Reservoir, growth is considered slow. The annual growth before maturation is 52 to 80 millimeters annually according to the sex. The threshold for a slow-growing population is 82 millimeters (MFFP, in press). In comparison, a walleye in the Baskatong Reservoir, where the size range exploited is 37-53 centimeters, reaches a total length of 32 centimeters at the age of three. To reach the same size at the Gouin Reservoir, walleye must survive for four to five years. Other data of interest total length at reaching sexual maturity. For males, the length at sexual maturity varies between 378 and 444 millimeters and from 452 to 493 millimeters for females. At the Gouin reservoir, the latter reach sexual maturity between the ages of 6.7 and 8.7 years depending on the sectors, while in the Baskatong reservoir, the age of maturity of the females is 6 years (MFFP, in press) . The health status of walleye populations in the Gouin Reservoir is not critical. Indeed, the abundance and average mass of walleye are high. However, local and regional partners have chosen to rely on quality fishing, in order to maintain the attractiveness of the Gouin Reservoir, hence the implementation of a range of sizes exploited. While such a measure requires adaptation for fishermen, they will be rewarded by the quality and abundance of walleye that bite the hook.

By Raphaël Dubé, Gouin Reservoir Management Corporation

Categories  :   Fishing

Tags  :   Discoveries