| Summary: | There is little information regarding the ecology of minke whales (Balaenoptera acutorostrata) in southern waters of the Northeast Atlantic. To improve the knowledge about the foraging ecology of this species and validate the use of complementary methods for baleen diet estimation, we analysed stomach contents (n=24, 2005-2023) and blubber fatty acids (n=10; 2005-2010) from minke whales stranded in the west coast of Iberia. Overall, the main prey identified in stomach contents analysis were Sardina pilchardus, Trachurus spp., species from the family Ammodytidae, Scomber spp. and species from the family Mugilidae with the former two prey groups being predominant (numerical importance (%N): 36.6% and 17.1% respectively; biomass (%W): 27.1% and 23.7%, respectively). Despite the low sample size, minke whales stranded in Galicia (n=4) showed a predominance of Scomber spp. (%N: 89.1%, %W: 77.3%) in their stomachs. Females (n=10) show a less diverse diet compared to males (n=14), mostly composed of species from Clupeidae, Carangidae and Scombridae families. Results suggest a shift in the diet of minke whales in west Iberia (2005-2015 vs. 2016-2023), possibly related with changes in sardine abundance in this region. The estimated length of the main prey ingested by minke whales was within the legal landing size allowed for fisheries in the west coast of Iberia, suggesting a potential minke whales-fisheries overlap in resource exploitation, which may be relevant for future conservation management. The quantitative fatty acid analysis supported the results obtained from stomach contents for the subsampled animals (n=10), validating, for the first time, the use of quantitative fatty acid analyses for a longer-term diet determination in baleen whales. This study comprises the first description of the diet composition of minke whales in the southern part of their distribution range, in the North Atlantic Poster.-- 35th Annual European Cetacean Society Conference, Catania (Italy), April 10-12 2024 No
|
|---|