Endocrine disruptors across generations in fish
Exposure to endocrine disrupting compounds at an early life stage can cause sex change in fishes, but little is known about how this influences population size or the overall fecundity of a population. We recently published work in Environmental Science and Technology describing how masculinization or feminization of group spawners such as Menidia species impacts overall reproductive output. In summation, we found that masculinization can be more detrimental than feminization.
Papers published in Scientific Reports and PeerJ demonstrate that silverside offspring sexual differentiation and fecundity, gene expression, as well as sex ratio, are influence by parental exposure to EDCs and increased temperatures. In ongoing work, silversides are being exposed to known EDCs to determine effects on gene expression and epigenetic effects (DNA methylation), and will soon be exposed with changes in salinity regimes in mind. Some endpoints are being evaluated over three generations to examine the potential for trans-generational effects. This work is currently funded by the Environmental Protection Agency (EPA Science to Achieve Results) and the Delta Science Program.
At Oregon State, we are investigating microplastic occurrence in rockfish caught near marine reserves, in otter scat, and in California mussels outplanted at ten sites along the West coast. Also, collaborators at the University of North Carolina Wilmington are using an interdisciplinary approach to complete a three-year study on the trophic transfer and effects of microplastics from zooplankton species such as favellids and larval fish to Black sea bass (Centropristis striata), as well as and the occurrence of plastic exposure in Black rockfish (Sebastes melanops). Related work was featured in the documentary A Plastic Ocean (2017) and Brander had the opportunity to speak on Capitol Hill in D.C. and to the legislature in Salem on microplastic pollution in 2019 . Brander and collaborators are funded by the NOAA Marine Debris program and the OSU Agricultural Research Foundation. Papers on microplastics will be out in late 2019 in a special issue of Limnology and Oceanography Letters and a special issue of Applied Spectroscopy.
Studies in invertebrates
Ongoing work in oysters (Crassostrea virginica) is examining the potential effects (both positive and negative) of aquaculture in research reserves, using tools such as quantitative PCR to link with higher level endpoints such as condition and recruitment. This research is funded by the NOAA National Estuarine Research Reserve (NERR) program.