CONFIRMED: SMAST Seminar - DFO - "Population Dynamics and Biology of Daubed Shanny (Leptoclinus maculatus), an Arctic-Boreal species that is Disappearing from the Gulf of Maine" by: Gary Nelson
Department of Fisheries Oceanography "Population Dynamics and Biology of Daubed Shanny (Leptoclinus maculatus), an Arctic-Boreal species that is Disappearing from the Gulf of Maine" Gary Nelson, Fish Biology Program Manager, Mass Division of Marine Fisheries Please note, due to the University wide mental health day 10/30 the seminar will take place on Tuesday 10/29 Tuesday, October 29, 2024 3:00 - 4:00 pm SMAST E 101-102 and via Zoom Abstract: The daubed shanny (Leptoclinus maculatus) is an Arctic-boreal fish species with a circumpolar distribution and whose southernmost extent of its range in the northwest Atlantic is the Gulf of Maine. Because life history characteristics of fishes often vary along latitudinal gradients, the daubed shanny population in the Gulf of Maine may exhibit different biological characteristics and population dynamics than the Arctic populations from which most information about the species comes. To improve our knowledge, this study was undertaken to document trends in temporal abundance, spatial abundance, and depth and temperature ranges based on historical trawl surveys, and to evaluate sex-specific differences in size, weight and age of individuals captured in the Gulf of Maine. The species was distributed throughout the western Gulf of Maine, primarily at depths from 30 to 120 m in spring and in waters >82 m in fall and was associated with the near-lowest temperatures available in the survey regions. Most daubed shanny were >8-9 cm total length in spring, but small fish (7-11 cm total length) dominated catches in fall, possibly representing pelagic post-larvae settling to the benthos. The population abundance of daubed shanny fluctuated widely since 1963 but appeared to collapse after 2009 in concert with warming temperatures and declines in Calanus copepod abundance in the Gulf of Maine. Female daubed shanny were larger and heavier than males, and both sexes reached a maximum age of 6 years. Compared to published data, daubed shanny in the Gulf of Maine has a shorter life span, grows faster and likely experiences higher natural mortality than the Svalbard, Norway population above the Arctic circle. *********************************************************** For additional information, please contact Callie Rumbut at c.rumbut@umassd.edu
See description for location
> See Description for contact information
https://umassd.zoom.us/j/93758230260?pwd=OHJ5UDloQkZZaCtXcTlBNlR6Qm0rQT09