Climate change could wipe out most Arctic reindeer in 75 years

By Stephen Beech

Arctic reindeer numbers could decline by 80% within 75 years due to global warming, warns new research.

Future climatic change is likely to cause declines in reindeer populations and their distribution at rates rarely seen over the last 21,000 years, say scientists.

Reindeer - also known as caribou in North America - are an Ice Age species that have survived many episodes of Arctic warming.

They are uniquely adapted to Arctic environments, where they regulate ecosystems and sustain the livelihoods of many indigenous people.

But, despite being one of the most abundant herbivores in the Arctic, climate change has contributed to a loss of nearly two-thirds of their global number over the last three decades.

An international research team looked back 21,000 years and examined how reindeer responded to previous climatic events, asking whether they will be able to cope in the future.

Lead investigator Dr. Elisabetta Canteri, of the University of Copenhagen in Denmark, said: “Using fossils, ancient DNA and computer models, we reconstructed changes in the abundance and distribution of reindeer over the past 21,000 years at resolutions never done before, and we directly compared these to future predictions.

“This revealed that populations of reindeer have experienced major declines during periods of rapid climate warming, but the losses expected in the coming decades due to future climate change are likely to be even more severe than those in the past.”

Populations in North America are "particularly vulnerable," according to the findings published in the journal Science Advances.

Study co-leader Professor Damien Fordham, of the University of Adelaide in Australia, said: “Our forecasts show that these North American caribou populations are most at risk from climate warming, with declines of up to 80% likely by 2100 unless there are major cuts to greenhouse gas emissions and increased investment in wildlife management and conservation.

“These declines are likely to have far-reaching ecological implications that will further increase the vulnerability of caribou in North America and reindeer in Eurasia to climatic warming and other stressors.”

The research team says reindeer and caribou help maintain plant diversity in the tundra by feeding on some and influencing how others grow, meaning that where they disappear, plant diversity is likely to decline.

University of California Professor Eric Post, who also contributed to the research, said: “A reduction in tundra plant diversity resulting from the loss of reindeer and caribou will have many cascading effects, including reduction of carbon storage in Arctic soils.

“Continued losses will likely further exacerbate climate warming through the release of soil carbon to the atmosphere, which of course, would further threaten reindeer and caribou as well as ourselves.

“For thousands of years, the well-being of our own species has benefited directly from healthy reindeer and caribou populations.

"Now more than ever we need to ensure their well-being in turn.”

Professor Fordham says the results of the research show urgent action is required.

He added: “Increasing investment in the management and conservation of reindeer and caribou populations, particularly in North America, where losses are forecast to be greatest, will benefit the persistence of this species and the services it provides to Arctic ecosystems and the communities that depend on them."