Estimating colony and breeding population size for nocturnal burrow-nesting seabirds

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 454:83-90 (2012) - DOI: https://doi.org/10.3354/meps09663 Estimating colony and breeding population size for nocturnal burrow-nesting seabirds Heather L. Major1,2,*, Alex M. Chubaty2 1Centre for Wildlife Ecology and 2Evolutionary and Behavioural Ecology Research Group; Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada *Email: heather.major3@gmail.com ABSTRACT: Estimating colony areas, locations, population sizes, and trends are all important aspects of managing animal populations. The ability to assess population trends and delineate important wildlife areas remains a top priority for managers and conservation biologists. Yet, outdated laborious estimation methods remain in high use. By simulating known populations on known island sizes and using established transect and quadrat survey methods, we asked whether using inverse distance weighting (IDW) interpolations in ArcGIS improved estimates of colony area and population size for nocturnal burrow-nesting seabirds over conventional global interpolation methods. We performed 100 simulations for each of 3 population sizes (500, 1000, and 50000 breeding pairs) on 3 island sizes (10, 50, and 500 ha), excluding the largest population size on the smallest island size, for a total of 800 simulated islands. We estimated colony area and population size for each simulated island using both IDW interpolations and an established global interpolation method, and the accuracy of each estimate was then calculated. Using an information theory approach, we found that IDW interpolation estimates were overall more accurate when estimating population size, but we found no difference in colony area accuracy between interpolation methods. We recommend using IDW interpolations to estimate colony area and population size along with consistency in survey structure both among study sites and years. We also recommend maintaining a consistent transect length whenever possible to ensure that observer bias does not influence areas surveyed. KEY WORDS: Colony size · Interpolation · Line transects · Population size · Seabird Full text in pdf format PreviousNextCite this article as: Major HL, Chubaty AM (2012) Estimating colony and breeding population size for nocturnal burrow-nesting seabirds. Mar Ecol Prog Ser 454:83-90. https://doi.org/10.3354/meps09663 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 454. Online publication date: May 21, 2012 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2012 Inter-Research.