AUTHORS: Justin Lombardo, University of Illinois Urbana-Champaign; Cory D. Suski, University of Illinois Urbana-Champaign; David P. Philipp, Fisheries Conservation Foundation; Joel Zhang, Carleton University; Joseph Parkos, Illinois Natural History Survey; Steven J. Cooke, Carleton University; Jeffrey A. Stein, Illinois Natural History Survey
ABSTRACT: Spring fishing for spawning black bass is a controversial topic. The aggressive behaviors exhibited by nesting males increases their susceptibility to angling, and should a nesting bass be removed by an angler, all offspring in that nest can be consumed by predators. Over time, this has potential to negatively impact populations, which may suggest the need for regulatory protection for nesting males. Unfortunately, long-term studies that track changes in black bass populations due to angling during the spawn have not been conducted, precluding our ability to make definitive conclusions about the impact on populations. The objective of this study was to quantify how reproductive and behavioral characteristics of spawning black bass in lakes Charleston and Opinicon in southern Ontario have changed due to angling pressure over a 32-year period compared with two control populations that have not received angling pressure. For this, nesting surveys were conducted during two sampling periods by snorkeling along the littoral zone in all four lakes to observe the mating success of nesting males. After snorkeling, nests were angled with 15 standardized casts to quantify susceptibility to angling. Results show that, from the 1990s to 2020s, there was no significant change in mating success in any of the studied lakes. The percentage of strikes on the first cast, however, significantly decreased in smallmouth bass in lakes Charleston and Opinicon, with no significant decreases in the control lakes. Similarly, in lakes Charleston and Opinicon, the percentage of strikes on any cast decreased in largemouth bass, with no significant changes in the control lakes. Results suggest that fisheries induced evolution may be negatively influencing black bass behavior and eroding their response to angling. Results will be further discussed in the context of protected areas to mitigate the consequences of angling.