Northern pike and muskellunge spawning ecology and reproductive success in the lower Ottawa River

Spawning (1995) and reproductive success (1994 and 1995) of northern pike (Esox lucius) and muskellunge (Esox masquinongy) were compared in two bays (Martin and Pentecôte) and one tributary (Kinonge River) of the Carillon Reservoir on the Ottawa River. Eggs collected in 60 cm x 60 cm baskets served to determine spawning sequences and differential utilization of habitat. The northern pike spawning sequence was similar at the three sites, the peak occurring between April 20 and 27. Muskellunge spawning peaked two weeks later in the Kinonge river (May 12-17) than in the two bays (April 27-May 5). Martin Bay had a second spawning peak during the May 16-19 interval. In the Kinonge River, northern pike egg deposition was more frequent in lentic, shallow, vegetated turbid sectors and on clay and silt dominated substrates whereas muskellunge egg deposition was more frequent in lotic, less turbid sectors on sand substrates with no vegetation present. Spawning habitat segregation was less pronounced in the two bays where trends in egg deposition of both species relative to environmental variables was more similar. Young-of-the-year seine catches–per-unit-of-effort suggest that northern pike reproductive success was nil in Martin Bay in 1994 and 1995; good in Pentecôte Bay and in the Kinonge River in 1994 but very low in 1995. Muskellunge reproductive success was good in both years in the Kinonge River but negligible in the two bays.