Meeting Abstract
Understanding the interaction between disease epidemics and host population genetic background is critical to predicting impacts and recovery potential. Since 2013, Sea Star Wasting Disease (SSWD) has led to a devastating marine epizootic which has caused drastic declines in many populations of sea stars along the west coast of North America. Among these is the small, six-armed sea star Leptasterias spp., which has faced severe but varying impacts as a result of this disease. Unlike larger stars, Leptasterias are direct developers and brood live young, which could lead to low gene flow and local differentiation or adaptation, suggesting that differing impacts between sites may have a genetic basis. To investigate the clade composition of sites differentially affected by SSWD, we used DNA sequence from the mitochondrial cytochrome oxidase subunit 1 to barcode 24 Leptasterias collected from two sites near Depoe Bay, Oregon. We compared this sequence to DNA sequence from northern California sites showing low disease impacts and central California sites showing strong impacts. At two Oregon sites surveyed here, Boiler Bay and Fogarty’s Creek, Leptasterias have persisted through SSWD in high abundance. Preliminary results from this study indicate that these Oregon populations show mitochondrial genetic similarity to many populations that have shown considerable decline in central California. These findings suggest that regional variation must be considered along with host mitochondrial clade composition.
