Marine associated bird and mammal habitat use at the Five Finger Lighthouse Island

Abstract

In summer 2017 I studied the abundance and distribution of marine associated birds and mammals from four observational points on the southernmost of the Five Finger Islands (FFI). My objectives were (1) to identify the areas of highest habitat use by species of conservation concern, and (2) to use this information to make recommendations for an ecosystem-based management plan at the Five Finger Lighthouse Island (FFLI). I found higher relative abundance and higher biodiversity of both birds and marine mammals on the South and West facing sectors compared to the North and East facing sectors. I attribute this to the greater habitat complexity that comprises a near-shore reef, a mixed kelp forest, and a channel between the reef and the side of the island with the highest cliff, areas used extensively for foraging, nesting, traveling, socializing, and resting by many of the documented species. I therefore recommend avoiding development and minimizing anthropogenic disturbance on the southern and western portions of the island including the adjacent reef and channel between the reef and island. As both the FFI ecosystem and the Five Finger Lighthouse (FFL) management continue to evolve in response to changing environmental conditions and human needs, this study provides a useful baseline for future comparison. Continued study and monitoring is also recommended at this site to inform future adaptive management, document changes over time, and engage community stakeholders in science and conservation.