Education Level
Undergraduate
Faculty Advisor(s)
Professor David Taylor
Academic Department(s)
Marine and Natural Sciences
Symposium Date
2024
Abstract
Mercury (Hg) is a bioaccumulative contaminant that can be transferred from pregnant females to developing embryos (i.e., intrauterine maternal Hg transfer); thus, leading to health deficits in offspring. This study examined Hg transfer in the ovoviviparous spiny dogfish (Squalus acanthias) and viviparous smooth dogfish (Mustelus canis). Female dogfish were collected from Narragansett Bay, Rhode Island Sound, and Block Island Sound via rod & reel, gillnet, and trawling. In the laboratory, intrauterine pups were excised from pregnant dogfish, after which samples of mother and pup muscle tissue were analyzed for total Hg concentrations ([Hg] in ppm dry weight) using automated atomic-absorption spectroscopy. Maternal muscle [Hg] was positively related to TL within both species, indicating bioaccumulation of the contaminant in mature females. Muscle [Hg] as a function of age followed similar trends between both species, however, Hg bioaccumulation was much higher in males than females for both species indicating the offloading of Hg to pups in females. Smooth dogfish pups exhibited higher muscle [Hg] than spiny dogfish pups, indicating a viviparous reproductive strategy results in higher amounts of Hg offloading than ovoviviparity. There existed a significant positive relationship between maternal and pup muscle [Hg] within smooth dogfish however no such relationship was exhibited in spiny dogfish. These results suggest that maternal Hg transfer occurs in both spiny and smooth dogfish, and the viviparous reproductive strategy of smooth dogfish results in higher amounts of Hg offloading to pups than the ovoviviparous strategy of spiny dogfish.
Recommended Citation
Taylor, David L.; Ajemian, Maxwell; and Remick, Abrielle, "Maternal mercury transfer from pregnant spiny (Squalus acanthias) and smooth (Mustelus canis) dogfish to their pups through differing reproductive strategies" (2024). Student Research Symposium. 9.
https://docs.rwu.edu/studentresearchsymposium/9
Comments
This research was presented at the 2024 Rhode Island Summer Undergraduate Research Symposium, held on Friday, July 26, at the University of Rhode Island and supported by independent research with Dr. David Taylor.