Dramatic global decrease in the range and reproduction rate of the European hamster Cricetus cricetus

A Surov,P Bogomolov,A Banaszek,N Feoktistova,S Monecke

doi:10.3354/esr00749

Abstract

Although the European hamster is probably the fastest-declining Eurasian mammal, its IUCN Red List status is still Least Concern. In addition to the huge distribution area, this categorization is based on the assumptions (1) that the decline affects only Western Europe, where (2) modern agriculture has led to (3) an increase in the mortality of the species. Since mortalityreducing protection measures in Western Europe have been unable to stop the decline, we reviewed the literature from 1765 to the present and reappraised the situation. We found support for none of these assumptions. The species has also vanished from more than 75% of its range in Central and Eastern Europe. In 48 of 85 Russian, Belarussian, Ukrainian and Moldovan provinces, its relative occurrence has decreased. It is now rare in 42 provinces and extinct in 8. Mortality has not increased, but the reproduction rate has shrunk since 1954 throughout the distribution area. Today the reproduction rate is only 23% of that between 1914 and 1935. Taking into account the mortality of this prey species, 1 female today raises only 0.5 females for next year’s reproduction. The extra polation of the literature data points to an extinction of the species between 2020 and 2038. We strongly recommend (1) changing the status of the European hamster on the IUCN Red List from Least Concern at least to Vulnerable or even Endangered and (2) supporting scientific research on the reproduction of European hamsters as a protection measure. Global threats such as climate change, light pollution or (in the past) fur trapping are more likely to be the ultimate reason for the decline of this species than modern agriculture.

Highlights

Until the 1970s, European hamsters were a much feared agricultural pest throughout their distribution area
Since the extrinsic mortality of European hamsters does not seem to have increased, we reviewed literature on their reproduction rate published since 1765 from across the distribution area, i.e. embryo numbers, litter size and the number of litters a female has in a year
If the low reproduction rate, which suggests a shrinking of the population by 50% each year in large parts of the distribution area, is incorporated, the status of Endangered (EN ) criterion A4 might be considered: A projected or suspected population size reduction of ≥50% over any 10 year period, [...] where the time period must include both the past and the future, AND where the reduction or its causes may not have ceased OR may not be understood OR may not be reversible (IUCN 2012, p. 19)

Summary

Introduction

Until the 1970s, European hamsters were a much feared agricultural pest throughout their distribution area. Since European hamsters prefer agricultural areas as habitat, farmers are compensated by 450 to 2250€ per year and hectare (Laussmann & Fabry 2008, Amand et al 2012, MKULN V 2013) for so-called hamster-friendly field management. This type of management aims to reduce mortality (Villemey et al 2013) presumably caused by industrialized agriculture and includes small-scale cultures, restricted ploughing and late or no harvest to provide year-long food and cover for hamsters (Kayser & Stubbe 2002, Köhler et al 2014, La Haye et al 2014). The French national action plan for the European hamster for 2012 to 2016 provided 4 400 000€ just for this purpose (Amand et al 2012)

Objectives

Findings

Conclusion