Fish and Game develops a new way to control fish populations

Sep 14, 2017 at 1:00pm

Roger Phillips, Idaho Department of Fish and Game

Fish and Game researchers and hatchery staff are collaborating on a project using 50 year-old technology to develop a monosex fish population whose offspring can only produce males. These males have two YY chromosomes (YY) rather than the usual XY arrangement.

Stocking YY-male hatchery fish into a body of water with an undesired fish population could change the sex ratio to all males within a few generations, and the unwanted fish population would eventually fail to reproduce and therefore die off. Once accomplished, Fish and Game would stop stocking those fish and fisheries managers would then restock that body of water with a more desirable fish species. 

Fish and Game officials hope the YY-male approach will be a cost-effective technique to control undesirable fish populations. Gary Byrne, the Fish Production Manger overseeing the hatchery portion of Idaho’s YY brook trout program, said it only took four years to develop the YY brook trout broodstock. 

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