Spawning Sanctuaries as an Approach to Meet Management Goals

A New Approach to Meet Management Goals

Over the past 30+ years, our black bass research group (scientists from Carleton University, University of Illinois, and Fisheries Conservation Foundation) have studied and monitored local smallmouth and largemouth populations.  These long-term studies have made the following relevant findings:

1. In order for bass fry to survive and recruit into a population, nesting male bass must continue to guard their offspring against predation until their fry are developed enough to be independent – a total of 4-6 weeks.
2. During that parental care period, if the male parent is removed from the nest via angling, his offspring can be consumed by predators very quickly.
3. Despite the current regulations that prohibit bass fishing until the 3^rd Saturday in June, the level of angling during the bass reproductive period has increased dramatically in lakes across the region.

This has resulted in populations of bass across the region are suffering from what we call recruitment overfishing. This occurs in bass when, there are chronically high levels of angling bass off their nests, preventing the replacement of young fish (recruits) into the population, leading to long-term declines of the fishery.

To counter the impacts of recruitment overfishing, proposed a new regulation strategy to protect nesting bass: the use of Bass Spawning Sanctuaries.  These are seasonally designated areas within a lake where all forms of fishing are prohibited during the critical period when fish such as largemouth and smallmouth bass are spawning and guarding their young.  They are an innovative conservation approach to improve and maintain the abundance of fish and the quality of recreational fishing.

Why are spawning sanctuaries important?

Spawning sanctuaries will fully protect all species of fish that spawn within their boundaries from the disruptions that angling can cause to their reproductive behaviors. Species such as largemouth and smallmouth bass go through a series of reproductive behaviors that includes courtship, nest building, spawning, and guarding their young until they are old enough to survive on their own and disperse.  When any of those activities are disrupted, the number of surviving offspring from that parent is reduced.  If those disruptions happen to many individuals within a lake, the number of surviving offspring and ultimately the number of surviving adults declines.

Spawning Sanctuaries in Ontario

In 2024, the Ontario Ministry of Natural Resources established bass spawning sanctuaries in two Ontario, Canada lakes: Charleston and Opinicon.  The regulation prohibits all fishing within the spawning sanctuary boundaries, from April 15 through the Friday before the first Saturday in July.

To determine how well the spawning sanctuaries protect nesting largemouth and smallmouth bass from pre-season angling, as well as how they affect the actual production of young bass, a coalition of research scientists have been conducting research both inside and outside the spawning sanctuaries during the nesting period.

The three main approaches to this research are:

• Snorkel surveys are used to assess how many largemouth and smallmouth bass build nests, spawn, and successfully produce offspring that are capable of surviving in the absence of the male guardian parent.
• Tracking fish movement using acoustic telemetry allows the research team to assess the individual fidelity to spawning areas, summer home foraging ranges, and overwintering areas of both species.
• Opinion interviews will assess how anglers feel about the new regulations and to answer any questions.