The COVID-19 pandemic gives the snow goose a short break

“Bad brings good,” says the proverb. We might believe this after reading a study published in Biological conservation by the team of the Department of Biology and the Center for Scandinavian Studies at the University of Laval. These researchers took advantage of the special conditions that prevailed during the first three years of the COVID-19 pandemic to answer a question they were unlikely to have studied otherwise: How would snow geese react if we halved the pressure during the spring hunt and what ? if we double it in subsequent springs?

“Spring snow goose hunting was allowed in Quebec in the spring of 2020, but public health measures, particularly those that limited travel between regions, resulted in fewer hunters. The following year, after the easing of health measures, hunting pressure increased,” emphasizes the first author of the study, doctoral student Frédéric LeTournay. This is evidenced by the number of geese killed in the spring. In 2020, this figure reached 10.6 thousand. In 2021 and 2022, the catch of geese increased to 21 thousand and 24 thousand, respectively.

Since 1999, a research team led by professors Gilles Gauthier and Pierre Leganier has periodically captured snow geese from the St. Lawrence River Estuary to assess how the females’ body condition changed over the three years preceding their departure to their breeding grounds. in the Canadian Arctic. “The captured geese are weighed and measured, which allows us to establish a body condition index that reflects their energy reserves,” explains Frédéric LeTournay.

In the years leading up to 2020 and into 2021 and 2022, female body condition index followed a similar pattern, increasing gradually between the start and end of the harvest period, reflecting the feeding of geese at this critical time of year. On the other hand, 2020 was an exception to this rule. The geese reached peak body condition about two weeks earlier than in other years and remained stable thereafter.

“Our hypothesis is that due to reduced hunting pressure in 2020, geese were less restless, they had to move less, they were less stressed, and their grazing efficiency was higher,” says Frédéric LeTournay.

Interestingly, tracking of females wearing GPS collars showed that they spent less time in agricultural fields in late spring 2020 than in other years, even though this environment provides them with a rich and plentiful food source. “Spring hunting takes place exclusively in agricultural fields,” explains the doctoral student. Our interpretation is that the geese realized that visiting these fields was risky. Once they had accumulated enough nutrients, they avoided agricultural fields.

Spring snow goose hunting was initiated in 1998 in Quebec due to the rapid growth of the species. At the time, we feared degradation of its habitats in the Arctic, the mouth of the St. Lawrence River and the Atlantic coast of the United States, as well as increased damage to agricultural fields.

“This conservation measure has worked, as the snow goose population has stabilized at almost a million,” emphasizes Frédéric LeTournet. Even after two decades, it is still effective because our research shows that geese are not yet accustomed to being hunted and still respond quickly to changes in hunting pressure. This suggests that the true impact of spring hunting on snow goose population dynamics is underestimated if only the number of geese harvested is considered.”

Research published in Biological conservation signed by Frédéric LeTournay, Frédéric Dulud-de Broen, Thierry Grandmont, Marie-Claude Martin, Gilles Gautier and Pierre Legagnier of Laval University, and Joël Béti of the University of Quebec at Rimouski.