GEOSCAN, résultats de la recherche


TitreThe potential of underwater imaging to evaluate lobster (Homarus americanus) density on different habitats
AuteurTremblay, M J; Smith, S J; Clement, P M; Todd, B J
SourceICES Annual Science Conference, abstracts; 2009 p. 139
Séries alt.Secteur des sciences de la Terre, Contribution externe 20120080
RéunionICES Annual Science Conference; Halifax, NS; CA; Septembre 22-26, 2008
ProvinceRégion extracotière de l'est
Lat/Long OENS-66.4167 -65.5000 43.6667 43.1667
Sujetstopographie du fond océanique; topographie du fond océanique; faunes; etudes fauniques; distribution de la faune; assemblages fauniques; peuplements biologiques; biomes; diversification biotique; écosystèmes; organismes marins; milieux marins; bathymétrie; géologie marine; géologie de l'environnement
ProgrammeLes géosciences à l'appui de la gestion des océans
Résumé(disponible en anglais seulement)
Habitat relationships of the American lobster have been studied via traps, scuba, and by trawls but to a much lesser extent by underwater video or still photography. Lobsters are often associated with shelters but in some areas are frequently in the open. In this paper we explore the potential of an underwater towed vehicle (Towcam) to estimate the density of lobsters and crabs on different bottom types. Towcam collects highfrequency still images and continuous video. A pilot study was undertaken in an area off southwest Nova Scotia where bottom mapping was available from multibeam and sidescan and where there are productive lobster and scallop fisheries. Lobsters were evident in more than 10% of the still images on some transects. On sand, gravel, and cobble bottoms lobsters were readily seen and could often be measured with reference lasers. On rougher bottoms with boulders, some lobsters were still evident either in the open or partially hidden in shelters. The paper will also discuss (i) methods for measuring field of view and (ii) methods for incorporating relationships between lobsters and bottom type (based on the images), into survey designs.