Space use and residency patterns of largemouth bass relative to a freshwater protected area

Abstract

Abstract Fish movement patterns are an essential consideration for the design of effective freshwater protected areas (FPAs). The Rideau Waterway system (Ontario, Canada) is home to some of the oldest single-resource FPAs in Ontario (> 70 years active). Initially, these FPAs were intended to provide holistic protection to the heavily exploited largemouth bass, but since their establishment, little is known regarding their protective capacity. Using a passive acoustic telemetry network, we measured how site fidelity varied with body size and across seasons in largemouth bass within one Rideau Waterway FPA. Collectively, 50 bass were tracked for an average of 227 days, with some individuals tracked upwards of 744 days. Tagged fish spent on average 55% of their time at liberty within the FPA, with occupancy rates exceeding 85% for some individuals. Most of the tagged fish displayed cyclical movement behaviour between the FPA and non-protected areas, largely corresponding with known life-history stages. Largemouth bass occupancy was highest in the spring-summer seasons (i.e., reproductive period), with a sharp decline during the fall that sustained through the winter. FPA occupancy varied with body size, with large fish (> 430 mm) using the FPA more extensively. Our findings show that this Rideau Waterway FPA provides temporal protection from exploitation to a highly targeted sportfish, especially during their reproductive period, likely providing major conservation benefits. These findings also highlight the value of considering the habitat requirements of a species across life-stages to inform effective FPA design.