Puget Sound Restoration Fund

Abstract Ecosystem-based fisheries management requires an understanding of the interactions between managed and unmanaged species and the connections they have with their habitats. Although aquatic plants are known to provide important shelter for a variety of species, an often-overlooked component is the extent to which primary producers contribute to their diet. In this study, we reconstructed the dietary connections between 18 consumers, including vulnerable rockfish species, and several primary producers. Two of these primary producers, Zostera marina (eelgrass) and Nereocystis luetkeana (bull kelp), have experienced spatial variation in abundance and substantial declines, respectively, within Puget Sound, Washington, USA. Using stable isotope ratio data, we estimated that both bull kelp and Smithora naiadum (an epiphytic algae) were the most important sources of carbon in consumer diets, followed by particulate organic matter and eelgrass. Our results indicated strong dietary connections for certain consumers, such that epiphytic algae was found to comprise greater than 40% of the diets of copper rockfish (Sebastes caurinus), while bull kelp contributed most to the diets of Pacific staghorn sculpin (Leptocottus armatus) and quillback rockfish (S. maliger). For several consumers, we observed habitat-mediated prey choice because the relative importance of bull kelp or epiphytic algae in their diets increased when these consumers were collected from sites dominated by kelp or eelgrass, respectively. Understanding the strength of these trophic relationships is an important step for predicting ecosystem consequences following perturbations within these habitats, and such information is vital to managers making decisions related to the conservation of valuable populations.

Arkema, K. K., L. A. Rogers, J. Toft, A. Mesher, K. H. Wyatt, S. Albury-Smith, S. Moultrie, M. H. Ruckelshaus, and J. Samhouri. 2019. Integrating fisheries management into sustainable development planning. Ecology and Society 24(2):1. https://doi.org/10.5751/ES-10630-240201

For long-term persistence of species, population structure is important. Traits that hold adaptive advantage such as reproductive timing and stress resilience may differ among locales. Knowledge and consideration of these traits should be integrated into conservation efforts. To test for adaptive differences between Olympia oyster populations a reciprocal transplant experiment was carried out monitoring survival, growth, and reproduction using three established populations of Ostrea lurida within Puget Sound, Washington. Performance differed for each population. Ostrea lurida from Dabob Bay had higher survival at all sites but lower reproductive activity and growth. Oysters from Oyster Bay demonstrated greater proportion of brooding females at a majority of sites with moderate growth and survival. Together these data suggest the existence of O. lurida population structure within Puget Sound and provide information on how broodstock should be selected for restoration purposes.