Department of Fisheries Oceanography

“Collapse, recovery and collapse of an important fishery”

Alex Hansell

Research Fishery Biologist, NEFSC

Wednesday, April 30, 2025

3:00 – 4:00 pm

SMAST E 101-102 and via Zoom

Abstract:

Georges Bank is a shallow plateau off the coast of New England that has supported productive fisheries for centuries. One of these fisheries targeted yellowtail flounder (Limanda ferruginea), which at its peak caught over 30,000 mt a year. However, over the last 100 years the stock has fluctuated, with periods of high abundance (1970s and 2000s) and low stock size (1990s and 2020s). A previous review published twenty years ago documented the collapse of the stock in the 1990s and subsequent recovery in the 2000s, hypothesizing the major reason for recovery was bilateral science and successfully coordinated management intervention. Unfortunately, by the time that review was published, the stock had started to decrease again and collapsed in the 2010s. Here, we update empirical indicators of spatial distribution and growth for Georges Bank yellowtail as well as apply a state-space stock assessment model that includes process error and environmental effects on annual recruitment. Results suggest that the stock has spatially contracted on the Bank, fish are smaller with less variation in size, and recruitment has decreased in recent years due to low stock size and increasing water temperature. These results give insight into an iconic New England groundfish stock, as well as, provide a unique opportunity to study the fluctuations of a stock through multiple periods of recovery and collapse.

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Join Zoom Meeting

https://umassd.zoom.us/j/93758230260

Meeting ID: 937 5823 0260

Passcode: 426839

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For additional information, please contact Callie Rumbut at c.rumbut@umassd.edu