Habitat Use of Finless Porpoises in Hong Kong

Abstract

Very little is known about finless porpoises (Neophocaena phocaenoides) in the waters surrounding Hong Kong. In light of recent development projects and an increase of vessel traffic, they have become increasingly threatened. In this project, I modeled the relationship of finless porpoises to their environment to better understand their habitat use. I used finless porpoise sightings and water quality data to predict suitable porpoise habitat. I also assessed the impacts of high speed ferry lines on the resulting suitable habitat. Specifically, I looked for patterns between sightings and water quality data, identified candidate environmental variables that drive finless porpoises to specific habitats, and, using habitat modeling techniques, I determined thresholds for habitat suitability. I used presence only data and Maxent for habitat predictions and Marxan as a spatial prioritization tool for conservation planning.  Based on my findings, I mapped suitable habitats and identified which areas conflict with the South Lantau high speed ferry line. The results of my models can be used to propose management recommendations.