Potential and Success in Spring 1994 of Walleye Spawning in the Salmon River, Tyendinaga Territory, Ontario, Canada

Abstract

This study assessed the potential and success of walleye spawning in the lower Salmon River during Spring 1994. It was estimated that between 12,000 and 40,000 adult walleye migrated up the Salmon River from the Bay of Quinte to spawn between 12 April and 11 May 1994. Conditions for spawning and embryo development were nearly optimal with spawning substrate, water temperature, dissolved oxygen, and pH all optimal. However, volume and depth of the river decreased daily from the first day of spawning (14 April) to the end of spawning (May 10). Therefore, walleye eggs deposited in shallow areas, at least 20% of the available spawning area, were at risk of desiccation and, therefore, the overall habitat suitability may have been less than optimal for shallow, near shore areas. An estimated 1,470,000,000 eggs were spawned in the nearly 9,000 m2 spawning area below the Shannonville dam. Between 1 May and 5 May, walleye eggs began to hatch and fry descended the Salmon River with the current to the Bay of Quinte. It was estimated that as many as 147,000,000 fry were recruited into the Bay of Quinte and at least 1%, or around 1,470,000, were expected to survive to fingerlings. Spearing impacted the spawning walleye population by eliminating 3,427 individuals; about 1,180 males and 2,228 females, which were mostly mature and in a ripe spawning condition, as well as, 19 walleye of undetermined sex. Spearfishing resulted in the removal of as many as 350,000,000 unspawned eggs. Approximately 1,000,000 walleye eggs were incubated in a community-built, owned and operated hatchery facility. About 85,000 fry were released into the Salmon River or aquaculture ponds.