Body condition index in beluga whale ( Delphinapterus leucas) carcasses derived from morphometric measurements

• Published in: Marine Mammal Science
• Main Authors: Larrat, Sylvain, Lair, Stéphane
• Other Authors: Fisheries and Oceans Canada, Parks Canada
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2021
• Subjects: Beluga; Beluga whale; Beluga*; Delphinapterus leucas
• Online Access: http://dx.doi.org/10.1111/mms.12855; https://onlinelibrary.wiley.com/doi/pdf/10.1111/mms.12855; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/mms.12855

Abstract Conservation efforts of the beluga whale ( Delphinapterus leucas ) of the St. Lawrence estuary include a mortality surveillance program which has the objective of documenting the causes of mortality. The evaluation of the animal's body condition is a key component in the diagnostic process. There is currently no consensual method to measure or calculate body condition indices in beluga whales. Morphological measurements recorded during necropsy were used to design a scaled mass body condition index that was compared to currently used visual evaluation, and to alternative morphological indices. Beluga whales were separated into two size‐based groups. The scaled mass index was well correlated with analog‐visual‐scale derived scores in beluga whale >290 cm, but not in animals <290 cm. Both methods showed almost perfect agreement regarding the categorization of carcasses belonging to the first quartiles. The alternative indices that were best correlated with the scaled mass index were those calculated using the sacral circumference and the ventral adipose thickness in animals <290 cm and the epaxial muscle mass and maximum circumference in beluga whales >290 cm. These scaled indices could provide objective tools to evaluate body condition of stranded beluga whales.