Date of Graduation

Spring 2018

Document Type

Honors Research Project

Degree Name

Bachelor of Science



Research Sponsor

Dr. Anne Wiley

First Reader

Dr. Randy Mitchell

Second Reader

Dr. Fransisco Moore


On the island of Kauai, black rats (Rattus rattus) are an invasive species that have been recorded by the Kauai Endangered Seabird Recovery Program (KESRP) to prey upon the federally endangered Hawaiian Petrels (Pterodroma sandwichensis) and threatened Newell’s Shearwaters (Puffinus auricularis newelli). The black rats were studied in order to determine whether the seabirds make up a significant portion of the black rat’s diet. Stable isotopes of d13C, d34S, and d15N in the black rat’s whiskers were analyzed to look at whether their diet was mainly terrestrial based or marine based. A marine based diet would indicate seabird predation by black rats. The whiskers were also able to show the individual black rat diet during the period of time of the growth of the whisker. The data collected was evident that the incidences of seabird predation by black rats were low, meaning that seabirds are not the primary nutrient source for the black rats.