Researchers analyzing the migration of red knot shorebirds, have found that the birds are getting smaller due to the effects of climate change. Red knot shorebirds’ migration goes from the Arctic into the Southern Hemisphere. This could mean a speedy extinction for the animal.

The study determined that warmer temperatures are contributing to the malnutrition of the birds in their breeding grounds in the high Arctic. Thus, making more complicated for smaller birds to get food and survive, as reported by National Geographic News.

Red Knot shorebird migration under climate change's menace
Researchers thought that smaller birds did better than the bigger ones, yet the study recently published in the journal Science shows how small red knot shorebirds could face starvation due to climate change. Image Credit: WNPR

For the study, the team tracked the subspecies of red knot that nests in northern Russia and winters on the tropical coast of Mauritania in West Africa. They used satellite imagery to look for a correlation between snow melt and the development of the birds.

“It is even worse than we thought,” said Michael Reed, a conservation biologist and bird expert who teaches at Tufts University outside Boston.

“This is going to increase their extinction risk, and the red knots are already in the highest-risk category,” Reed added in the statement.

Researchers found the breeding grounds have been progressively melting. At a faster pace than they were almost 30 years ago. This means the area’s schedule has changed and the insects the birds eat are emerging earlier. Therefore making red knots get there too late to eat them. So it’s safe to assume the migration has shifted into a race for food. The early bird gets the worm, as they say.

As a consequence, the malnutrition affects the body size and makes it harder for smaller birds to get any food at all. Instead of insects, birds are now eating more sea grass, a less nutritional alternative.

Climate change could be a reason for bird’s decreased survival rates

The survival rates among the shrunken red knots are significantly smaller than the larger juvenile birds. The smaller birds have almost half the chances to survive than the bigger ones. This is because they are still able to retrieve clams and such burrowed in the sand, according to Jan van Gils. The study’s author Jan van Gils is a senior scientist at the Royal Netherlands Institute for Sea Research.

Previously, it was thought that smaller birds did better than the bigger ones. Because shrinkage was a possible adaptation to climate change in view to the fact smaller birds dissipate body heat better, van Gils said. However, the study published recently in the journal Science proved the case is the opposite. Showing how smaller birds are having a harder time surviving, especially when migrating.

Source: Science