Kevin L. Kapuscinski

Muskellunge and Northern Pike Ecology and Management: Important Issues and Research Needs

New research techniques and changing Muskellunge Esox masquinongy and Northern Pike E. lucius fisheries have contributed to paradigm shifts in the science and management of these species. A symposium on Muskellunge and Northern Pike biology, ecology and management was held at the American Fisheries Society Annual Meeting in Little Rock, Arkansas, and a panel discussion following the symposium identified several research and management priorities, including spawning habitat identification, habitat and population restoration, genetics, and selective mortality and exploitation. Future Muskellunge and Northern Pike research should focus on quantifying egg and age-0 survival based on habitat characteristics, rigorously evaluating habitat restoration efforts using statistically sound study designs, describing range-wide genetic structure of populations, and developing a better understanding of how selective mortality and exploitation can alter population size structure, sex ratios, and life history characterist...

Feeding patterns and population structure of an invasive cyprinid, the rudd Scardinius erythrophthalmus (Cypriniformes, Cyprinidae), in Buffalo Harbor (Lake Erie) and the upper Niagara River

Feeding patterns and population structure of the non-native rudd Scardinius erythrophthalmus (Linnaeus) were examined to understand their ecology in Buffalo Harbor and the Niagara River. We hypothesized that (1) the diet of rudds would be omnivorous, but contain greater proportions of macrophytes in summer months, (2) feeding intensity would increase with water temperature, and (3) condition and growth would be similar to other populations. We collected rudds with a variety of gears in 2009 to test these hypotheses, and used data from 2007 to 2010 seining surveys to determine if the relative abundance of young-of-the-year rudd differed among sites with different flow conditions. Rudds were mostly herbivorous; they consumed aquatic macrophytes in summer and supplemented their diet with algae and fish in spring and fall. Feeding intensity was positively correlated with water temperature, but significantly reduced during spawning. Rudd condition and growth were greater than estimates from other populations, suggesting increases in abundance and range expansion are possible. Furthermore, reproduction was successful at lotic sites but very poor at sites without measureable flow, contrary to the paradigm of optimal rudd habitat. Research is needed to understand how herbivory by abundant rudd populations affects native aquatic communities.

First Report of Abundant Rudd Populations in North America

Abstract The rudd Scardinius erythrophthalmus was first introduced into U.S. waters about a century ago, and the species’ popularity as a baitfish in the 1980s has facilitated its spread to at least 21 states and the province of Ontario. Several established populations have been identified, but low abundances have led to little research and management attention. Rudds comprised 48.7% of the 14,130 fish captured in spring trap-netting surveys of Buffalo Harbor (northeastern Lake Erie) and the upper Niagara River during 2007–2008. Rudd was the most abundant species sampled, being captured at 11 of 12 locations and comprising 23.6% of the total catch in Buffalo Harbor and 70.3% of the catch in the upper Niagara River. Documented presences and absences in historical reports indicate that rudd became established in these waters between 1986 and 1991. Research is needed to understand the effects of rudds on native aquatic resources, especially nearshore macrophyte assemblages and the fish they support. Received...

Feeding Strategies and Diets of Young-of-the-Year Muskellunge from Two Large River Ecosystems

Abstract We analyzed stomach contents from 674 young-of-the-year (age-0) muskellunge Esox masquinongy sampled in New York waters of the St. Lawrence and upper Niagara rivers to (1) describe diets and document use of nonnative prey, (2) examine the feeding strategy (generalized versus specialized) and the importance of different prey types, (3) evaluate temporal patterns in feeding strategy and prey importance, and (4) determine how prey length related to muskellunge length and whether this relationship differed among prey types. Banded killifish Fundulus diaphanus, native cyprinids, and tessellated darters Etheostoma olmstedi were the most important prey numerically and by weight in the St. Lawrence River. Native cyprinids, banded killifish, and darters (Etheostoma spp. and Percina spp.) were the most important prey in the Niagara River, but nonnative cyprinids were more important by weight than darters. Muskellunge from both rivers exhibited a specialized feeding strategy, with individuals specializing o...