A steppe-dwelling rodent species called the Brandt’s vole (Lasiopodomys brandtii) actively modifies habitat structure by cutting down a large, unpalatable species of bunchgrass in the presence of shrikes, a behavior that disappeared when these avian predators were excluded experimentally.
Using field surveys and manipulative experiments, Zhong et al. evaluated how habitat modification by Brandt’s voles (Lasiopodomys brandtii) influences predation risk from shrikes in a steppe grassland, located in Inner Mongolia, China. Image credit: Guoliang Li.
The Brandt’s vole is a steppe-dwelling species of rodent in the family Cricetidae.
This species is currently distributed from the central parts of Inner Mongolia, China, through the central and eastern Mongolia, and to the southern borders of Mongolia in Trans-Baikalia.
Also known as the steppe vole, it is commonly found in grassland areas. Its typical habitat is dry steppes and pastures.
In a new study, University of Exeter researcher Dirk Sanders and his colleagues found that Brandt’s voles cut tall bunchgrass (Achnatherum splendens) when shrikes (Lanius spp.) are nearby.
The voles don’t eat or use the bunchgrass, they cut it to keep themselves safe, an example of ecosystem engineering.
“When shrikes were present, the voles dramatically decreased the volume of bunchgrass,” Dr. Sanders said.
“This led to fewer visits from shrikes — which apparently recognize cut-grass areas as poor hunting grounds.”
“An activity like this is costly for the voles in terms of energy, so there must be high ‘selection pressure’ to do it — cutting the grass must significantly improve their chances of survival.”
The researchers also tested the impact of keeping birds away, by putting up nets over certain areas.
With no shrikes overhead, the voles stopped cutting the bunchgrass.
“We sometimes underestimate the ability of wild animals to react to changes in their environment,” Dr. Sanders said.
“In this case, the voles were able to change their behavior in response to the removal of predators.”
“Our findings are a reminder that species show remarkable adaptations,” he said.
“It also underlines that the loss of even a single species in a food web can result in unexpected changes to an entire habitat.”
“This study provides a good example that animals can actively modify their habitat to reduce predation risk,” said Dr. Zhibin Zhang, a researcher in the State Key Laboratory of Integrated Management of Pest Insects and Rodents at the Institute of Zoology of the Chinese Academy of Sciences.
“The finding would have some implications in rodent management in pasture land,” added Dr. Zhiwei Zhong, a researcher at Northeast Normal University.
“Keeping or planting these large bunchgrasses may help to attract shrikes, and then to reduce the population density of voles.”
The study was published in the journal Current Biology.
_____
Zhiwei Zhong et al. A rodent herbivore reduces its predation risk through ecosystem engineering. Current Biology, published online March 11, 2022; doi: 10.1016/j.cub.2022.02.074
Source link: https://www.sci.news/biology/brandts-vole-ecosystem-engineering-10613.html
