Reindeer adaptability 

By Dawn Wiseman

Biologist Robert Weladji says most organisms are more adaptable than we realize, including humans. Originally from the African nation of Cameroon, Weladji is an expert on reindeer populations across northern Europe.

Robert Weladji in northern Europe is flanked by a single reindeer. Magnifying glass

Robert Weladji in northern Europe is flanked by a single reindeer.

“I like challenges,” he said with a smile. “I know people do not expect me to work with this species, but while working for the World Wildlife Fund rhino project in Cameroon, one of my supervisors was a black rhino expert from Scotland.”

Weladji’s trip from the intense heat of Africa to the sub-zero cold of Scandinavia was precipitated by funding for his PhD. “The proposal was generally aimed at work on population dynamics of large herbivores.” Because the sponsoring agency was based in Norway, it preferred a focus on northern herbivores, and hence reindeer.

Reindeer (or caribou, as they are called in Canada), are semi-domesticated in Finland, Scandinavia and Russia. They migrate over long distances, following relatively fixed routes from winter through summer.

Weladji’s focus is population ecology and biodiversity conservation. Each year he travels to the animals’ range for fieldwork. One of his current projects examines the behaviour and the dynamics of the reindeer during the rut, or breeding season.

“One thing we have found is that having too many young males mixed with the older males is a bad combination for herd productivity.” The reindeer breeding season is short, one to two weeks. The health of the herd as a whole relies to an extent on every mature female becoming pregnant.

Weladji and his collaborators from Finland and Norway have all noted the problems associated with the presence of many young males.

“Young, inexperienced males spend time attempting to mate with females who subsequently try to escape. At the same time, dominant males spend time chasing the younger males off, becoming exhausted and having less time to mate with females in heat.” Consequently, some of the females do not get pregnant at all. And, more importantly, “All the animals are using their energy in a very inefficient way at a time of year when they cannot afford to lose weight.”

Reindeer gain all of their weight during the short northern summers when high food- value plants are in bloom. They need that weight to sustain them through the winters when all they can eat is lichen, a plant-like substance common in tundra and taiga areas. Lichen can keep them alive, despite its low food value.

“There is no weight gain in winter,” said Weladji. “In winter they often lose weight. The lichen is not enough for their maintenance, so anything which impacts weight before winter is not good for the herd.”

That the reindeer can survive on lichen at all is a testament to their adaptability and supports Weladji’s research into the impact of climate change on the herds.

“We know that the physical features of their range are changing, we know that these changes will have effects on population dynamics, but the effect will vary greatly between populations, so that we cannot predict with any certainty whether the overall impact will be positive or negative.” In either case, he believes the reindeer will certainly adapt because they are remarkably resilient animals.

Weladji’s reindeer work is ongoing and will bear fruit for a long time to come. He already has one graduate student working with him on these projects. For the moment, however, he is more excited about the opportunities that have arisen since finding a home at Concordia in July of this year.

“My dream has been to apply the knowledge I have acquired about large herbivore population ecology to the management and conservation of wildlife in Africa,” he explained. In January, he will get that opportunity with a new grad student whose research focuses on black rhino population dynamics.

“I’m very excited by this opportunity to create a new niche for students who are interested in tropical-related research. I’m looking forward to attracting good students to this ambitious program.”


Concordia University