12 November 2024: New study reveals distinct foraging strategies in Norwegian killer whales

A recent study by Vogel and colleagues, titled “Norwegian killer whale movements reflect their different prey types,” was published in Polar Research in March 2024. The research examines the feeding behaviours of Norwegian killer whales and reveals two main foraging strategies. Using field observations and stable isotope analysis (a technique that identifies chemical traces in tissue to help determine diet and habitat) the researchers classified the whales as either “seal-eaters” or “fish-eaters.”

Satellite tracking data showed that seal-eaters travel along coastal routes, staying on average 6.9 km from shore, while fish-eaters head further out, averaging around 45.1 km offshore along the continental shelf. Seal-eaters also showed a preference for areas where harbour seals rest on land. The study suggests that fish-eaters focus on fish for their diet, while seal-eaters adjust their foraging, primarily targeting seals but opportunistically eating fish based on availability.

These findings demonstrate how tracking data can help scientists understand how Norwegian killer whales choose and hunt their prey, shedding light on their movement and feeding patterns.

Read the full article here: https://doi.org/10.33265/polar.v43.9840

Photo credit: Fernando Ugarte