Cookies

We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.


Durham Research Online
You are in:

Remote estimation of grey seal length, width and body mass from aerial photography.

Twiss, S.D. and Pomeroy, P.P. and Thomas, C.J. and Mills, J.P. (2000) 'Remote estimation of grey seal length, width and body mass from aerial photography.', Photogrammetric engineering & remote sensing., 66 (7). pp. 859-866.

Abstract

High-resolution images of two UK grey seal breeding colonies were derived from multi-temporal aerial photography and geo-referenced in a GIS using ground control points obtained in the field with sub-meter DGPS. Lengths and widths of seals were digitized from these images. Elevations at seal locations were determined using sub-meter DEMs, allowing measurements to be adjusted for proximity to the camera. Mass estimates of seals were computed from these measures using models developed from direct field measurements. Comparisons of estimates derived from the images and actual masses of seals measured in the field indicate that this method provides a consistent index of relative body size. Seasonal patterns of changes in remotely determined size and mass estimates and inter-colony comparisons mirrored patterns observed from direct field measurements. Our work permits the remote estimation of seal body size for any sample of seals without the intrusive complications and sample limitations of direct field measurements.

Item Type:Article
Keywords:Halichoerus-Grypus, North-Rona, Site fidelity, Scotland, Success, Size, Dipersion.
Full text:Publisher-imposed embargo
(AM) Accepted Manuscript
File format - PDF (Copyright agreement prohibits open access to the full-text)
(267Kb)
Full text:(VoR) Version of Record
Download PDF
(2453Kb)
Status:Peer-reviewed
Publisher Web site:http://www.asprs.org/PE-RS-Journals-2000/PE-RS-July-2000.html
Date accepted:No date available
Date deposited:17 March 2014
Date of first online publication:July 2000
Date first made open access:No date available

Save or Share this output

Export:
Export
Look up in GoogleScholar