Kelp and seaweed feeding by High-Arctic wild reindeer under extreme winter conditions

One challenge in current Arctic ecological research is to understand and predict how wildlife may respond to increased frequencies of “extreme” weather events. Heavy rain-on-snow (ROS) is one such extreme phenomenon associated with winter warming that is not well studied but has potentially profound...

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Bibliographic Details
Published in:Polar Research
Main Authors: Brage Bremset Hansen, Ronny Aanes
Format: Article in Journal/Newspaper
Language:English
Published: Norwegian Polar Institute 2012
Subjects:
geo
Online Access:https://doi.org/10.3402/polar.v31i0.17258
https://doaj.org/article/9d46eb9625fe42d088df170482084079
Description
Summary:One challenge in current Arctic ecological research is to understand and predict how wildlife may respond to increased frequencies of “extreme” weather events. Heavy rain-on-snow (ROS) is one such extreme phenomenon associated with winter warming that is not well studied but has potentially profound ecosystem effects through changes in snow-pack properties and ice formation. Here, we document how ice-locked pastures following substantial amounts of ROS forced coastal Svalbard reindeer (Rangifer tarandus platyrhynchus) to use marine habitat in late winter 2010. A thick coat of ground ice covered 98% of the lowland ranges, almost completely blocking access to terrestrial forage. Accordingly, a population census revealed that 13% of the total population (n=26 of 206 individuals) and 21% of one sub-population were feeding on washed-up kelp and seaweed on the sea-ice foot. Calves were overrepresented among the individuals that applied this foraging strategy, which probably represents a last attempt to avoid starvation under particularly severe foraging conditions. The study adds to the impression that extreme weather events such as heavy ROS and associated icing can trigger large changes in the realized foraging niche of Arctic herbivores.