Changes in minke whale distributions in the Southern Ocean ...

• Main Authors: Beekmans, Bas W.P.M., Forcada, Jaume, Murphy, Eugene J., de Baar, Hein J.W., Bathmann, Ulrich V.
• Format: Conference Object
• Language: unknown
• Published: ASC 2008 - Theme session B 2024
• Subjects: Arctic Sea FAO area 18; Ecosystem observation, processes and dynamics; Arctic; Austral; Southern Ocean; minke whale; Sea ice
• Online Access: https://dx.doi.org/10.17895/ices.pub.25243483.v1; https://ices-library.figshare.com/articles/conference_contribution/Changes_in_minke_whale_distributions_in_the_Southern_Ocean/25243483/1

No abstracts are to be cited without prior reference to the author.This study explores the various relationships between distance from the sea ice edge and minke whale density distribution by means of a circumpolar spatial analysis. For almost 30 years, the International Whaling Commission (IWC) has conducted whale surveys in the Southern Ocean during austral summer months under the IWC/IDCR-SOWER programme. This has resulted in three circumpolar sets of surveys, with over 21,000 minke whale sightings. We used these sightings in spatial models of line transect data based on generalised additive models (GAMs). The GAMs assumed an overdispersed Poisson error structure and log-link. Model selection was based on maximisation of explained deviance and minimising the Generalised Cross Validation (GCV) score, while excluding GAMs that generated extreme and unlikely minke whale densities. The GAMs were fitted independently by survey area and year. Selected GAMs included combinations of the following covariates: ...