Project Information

Title: Pigeon Guillemot Restoration 19110853

Project Year and Number: 2019: 19110853

Other Fiscal Years and Numbers for this Project: 2023: 23110853 , 2022: 22110853 , 2021: 21110853, 2020: 20110853, 2018: 18100853, 2017: 17100853, 2016: 16100853, 2015: 15100853, 2014: 11100853-Am.8.29.13, 2011: 11100853

Principal Investigator (PI): David Irons (USFWS), Robb Kaler (USFWS), Kathy Kuletz (USFWS)

Managing Agency: USFWS

Assisting Personnel: None

Research Location: Prince William Sound

Restoration Category: General Restoration, Monitoring, Research

Injured Resources Addressed: Pigeon Guillemot

Abstract:

Historically, the Naked Island group had the largest breeding population of pigeon guillemot (Cepphus columba) in Prince William Sound (PWS), Alaska, but it declined over 90% after the 1989 Exxon Valdez Oil Spill. Following the effects of the oil spill, predation of adults and their nests by introduced American mink (Neovison vison) was the primary factor limiting population recovery. However, with the major changes in the ocean ecosystem in the Gulf of Alaska in the past few decades, sufficient food availability for nesting has also been a concern, as the guillemots in PWS overall have been gradually declining since the oil spill. Mink trapping in guillemot nesting areas was conducted 2014-2018 and mink were caught during the first three years (2014-2018; 76, 23, 7, 0, and 0 mink, respectively). In 2017, mink tracks were observed at one location, but no mink were caught. In 2018, no mink tracks were observed and no mink were captured. While trapping was restricted to pigeon guillemot nesting areas, which were placed along 70% of the shoreline throughout the islands, male mink were likely traveling greater distances in search of females, thereby increasing their exposure to traps. During this 5-year restoration study, counts of pigeon guillemots at Peak, Naked and Story islands has more than doubled from 2014-2018 (69 to 167 individuals) and numbers of nests increased more than four times (11 to 51 nests). Enough food has been available to allow good breeding success the last three years. Numbers of pigeon guillemots counted at control islands did not show a similar increase in population gain. From a management perspective, it is important to determine if mink are absent from the islands, when or if they might return and at what numbers will they start having an effect on the pigeon guillemots again. We propose to continue to: (i) search for evidence of mink in guillemot breeding areas, (ii) monitor the recovery of pigeon guillemots, and (iii) monitor relative food availability, using black-legged kittiwakes (Rissa tridactyla) as indicators. While we expect no mink remain on the Naked Island group, we propose three additional years of winter/spring monitoring using bait stations, camera traps, and track surveys focused on 10 previously high-density mink areas to determine need for continued management of mink. To monitor continued population recovery of guillemots, we propose five years of annual guillemot population surveys. The surveys would be conducted, as they have been in the past, in spring at the Naked Island group and control islands (Fool, Seal, Smith and Little Smith islands). To monitor relative food availability, we will use black-legged kittiwakes as an indicator. We propose a cost efficient survey to follow productivity trends of black-legged kittiwake colonies in PWS to provide information on the relative availability of food for nesting. Together, these data will inform future management actions by determining if mink are absent from the islands, measure the rate of recovery of pigeon guillemots following the removal of mink, and provide an indicator for productivity patterns of ocean conditions to help interpret pigeon guillemot population trends.


Proposal: View (300 KB)

Information and/or Products produced by this project:
Title Description Type Document(s)
Sam Stark MS Thesis Other View (988 KB)

Reports:
Annual Report FY19: View (799 KB)
Final Report: See Project 23110853

Publications from this Project: None Available