Page 38 - Green knowledge 2024

Photo: Ingrid Bjørndal Foss
Climate change affects deer
Climate change impacts deer on many levels, from physiology and behaviour to population
dynamics. A new study, based on 218 scientific articles, indicates that warmer summers are
likely to have a have a larger impact than milder winters.
NIBIO researchers Dr Hilde K. Wam and Dr Aksel
Granhus are part of a European team that has
reviewed 20 years of research on how climate change
impacts deer in boreal and temperate forests of the
Northern Hemisphere.
Milder winters can benefit many species, such as
moose, deer, and roe deer, who then need less energy
to stay warm and can find food more easily. How-
ever, warmer and wetter summers may exceed the
animals’ tolerance, increasing the risk of heat stress
and parasite infection. Over time, this is likely to
weaken populations, particularly in southern
regions, forcing them to migrate further north.
Moose are especially sensitive to heat. Data from
Sweden already show that southern populations are
struggling more than northern ones. To adapt, ani-
mals may seek cooler environments such as wetlands
and mature forests or change their activity patterns.
It is vital that their habitats provide access to these
resources.
Changes in spring and autumn weather also influ-
ence migratory patterns. The snow season is becom-
ing shorter, prompting deer to begin spring migra-
tions earlier. They encounter flooding at unusual
times, and they delay their return in the autumn.
This may lead some populations to the abandon
migrations altogether.
“It’s difficult to predict exactly how future climate
will evolve and how this will affect deer. Our study
does not provide definitive answers, but so far it rep-
resents the largest synthesis of current knowledge
relevant to Norway,” Dr Wam concludes.
Purpose: Collaboration: To understand how deer are affected by climate change.
Swedish University of Agricultural Sciences (SLU), Skogforsk (Sweden), Natural Resources Institute
Finland (LUKE), National Research Institute for Agriculture, Food and Environment (INRAE, France)
and Forest Research Institute (Poland)
Funding: Nordic Forest Research (SNS)
Contact: Research Professor Hilde Karine Wam, Division of Forest and Forest Resources.
Email: hilde.wam@nibio.no | Phone: +47 920 10 746
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