The Paradox of Invasive and Imperiled Brook Trout: A Review of Several Tools to Manage These Populations

Fisheries biologists develop the best science possible to combat invaders or rescue imperiled populations but do little collaborative thinking.  This is not surprising since our goals and objectives differ completely.  In this paper, I review several tools for pursuing these dichotomous objectives in Brook Trout management.  A relatively unknown, but potential biological eradication alternative, is a Trojan Y Chromosome (TYC) program where genetically YY male fish could be regularly released into an undesired population over time, hopefully resulting in population extinction.  A genetic sex marker used to develop a potential TYC broodstock for Brook Trout revealed a male-biased sex ratio of about 60:40 for age zero Brook Trout residing in five Idaho streams.  Such data have population dynamics implications for depressed Eastern stocks if similar ratios there are the norm.   Basic life table data, rare for any Brook Trout population, can be used for simulating either suppression or enhancement efforts.   Other potential management approaches, such as use of Tiger Muskie to eliminate Brook Trout in high lakes, are of a decidedly one-sided nature.   However, I conclude that more geographic collaboration among entities employing recently developed tools for wild Brook Trout could benefit managers on both ends of the spectrum.