Lake Sturgeon Can Live for Centuries

Some of the Great Lakes' biggest fish may have birthdays that predate the United States by centuries. A new study suggests female lake sturgeon can live up to about 427 years and males to 279—nearly tripling an earlier lifespan estimate of up to 150 years and putting them in the same league as the ultra-long-lived Greenland shark, reports MLive. Instead of counting growth rings on ear bones or fin spines, which become unreliable for "slow-growing, long-lived species," researchers analyzed 44 years of tag-and-recapture data from five sturgeon populations in Michigan and Wisconsin to model how long it takes fish to reach certain sizes.

As the Michigan Department of Natural Resources, which was involved in the study, explains, "Unlike people, who stop growing taller after reaching maturity, fish continue to grow throughout their lives," which makes such analysis possible. The work, published in the Journal of Fish Biology, has direct implications for managing the threatened species, which matures late and reproduces slowly. The findings support strict harvest rules like those at Michigan's Black Lake, where the entire winter sturgeon season can end within minutes; last year's quota for the entire lake was six fish. That syncs with researchers' recommendation: "Harvest limits for lake sturgeon should be conservative to ensure population sustainability."