Science Advisory Report 2012/047
Advice on the northern Hudson Bay narwhal population based on stock dynamic modelling of 1982-2008 aerial surveys
Summary
- The analysis suggests that the 2008 survey estimate was not reliable because the model could not be fitted to that survey without considerable adjustment.
- It reinforces the contention that the survey was severely affected by biases that produced an unrealistically low number for the NHB narwhal population. Modelling with increased killer whale predation starting in 2000 allowed a better fit to the 2008 survey estimate but only if predation removals were quite high.
- The modelling results are uncertain. Without more recent surveys to inform the model, estimating future sustainable catches for the Northern Hudson Bay narwhal population is difficult.
- It is recommended that a new survey be conducted as soon as possible to inform population trend and sustainable catches.
This Science Advisory Report is from the November 22-26, 2010 National Marine Mammal Peer Review Committee (NMMPRC) annual meeting. Additional publications from this process will be posted as they become available on the Fisheries and Oceans Canada Science Advisory Schedule.
Accessibility Notice
This document is available in PDF format. If the document is not accessible to you, please contact the Secretariat to obtain another appropriate format, such as regular print, large print, Braille or audio version.
- Date modified: