Nathaniel Tennies, “Where Will it Grow? Bull Kelp Distribution Modeling in the Salish Sea”
Mentor: Filipe Alberto, Biological Sciences
The bull kelp, Nereocystis luetkeana, is a foundational species for aquatic ecosystems in the Salish Sea on the border of Washington and British Columbia. Its ecological importance, population contractions, and the present environmental pressure in these bodies of water require an increased research effort on bull kelp dynamics in the Salish Sea. We’re approaching this issue by developing a species distribution model (SDM) to predict, in a spatially explicit way, the probability of N. luetkeana occurrence across the Salish Sea. These SDM models are built from presence and absence species occurrence data (the response variable) and its association with a set of spatially explicit environmental data (the predictor variables). Environmental data were obtained from the Aqua-MODIS NASA satellite, the Bio-ORACLE global marine dataset, and local digital elevation models. Model development started in summer 2019 and is planned to be finished during spring 2020. The main technique we’re using is generalized linear modeling, a form of multiple regression analysis better suited for presence-absence responses. Once our first model is finalized, we intend to use other model types and compare the results. We will compare the different modeling approaches on their accuracy and set of predictors identified in association with species probability of occurrence. An SDM model will be valuable to guide current restoration efforts of the species before spending resources on reestablishing extinct populations in places where the local environment is no longer suitable.