Freya in better days, photographed by WMR-colleague Jeroen Hoekendijk. Analysis of walrus faeces found along the North Sea coast and Norwegian waters on several occasions between February 2021 and April 2022 shines a new light on the species’ distribution.
The walrus, known as Freya in the Netherlands, visited the Wadden Sea on at least two occasions in the aforementioned period, during which she defecated, among other locations on the Zr. Ms. Dolfijn submarine, which was at anchor in Den Helder. Thanks to excellent contacts with the navy, researcher Sophie Brasseur (Wageningen Marine Research) managed to acquire the faeces. She also managed to get her hands on the droppings produced two weeks earlier on Terschelling, thanks to a local vet.
Analysis of the faecal sample revealed that Freya’s diet consisted solely of Atlantic jackknife clams (Ensis leei), an invasive species abundant in the North Sea and the Wadden Sea. YouTube footage showing her spitting out empty jackknife clam shells confirms that this was, indeed, on the walrus’ menu.
No shortage of food. Elevated water temperatures also seemed to be no problem; the water she encountered on her journeys was frequently above 20°C. This did not seem to affect her.
Other reasons
According to Brasseur, these observations suggest that walruses typically stay in the Arctic region for reasons other than those that were hitherto assumed. Not due to water temperatures of the availability of food, but because they might otherwise be exposed to over-hunting or disturbances.’
And, now that the north-eastern Atlantic Ocean is becoming busier -both as a result of the walrus population growth and human activities- while the area of ice sea is reduced, she expects walruses may move further south. There is no shortage of food, jackknife clams abound.
Accident waiting to happen
Preparing for this would be wise, she stresses. After all, Freya’s story ended badly: she was killed by Norwegian authorities in the Oslo harbour in August of 2023. Not for being intrusive or aggressive, but because humans persisted in approaching the animal despite repeated warnings, creating an accident waiting to happen. Norwegian authorities wanted to prevent this. Adequate measures can prevent situations where culling seems the only option, she concludes.