Climate change impacts the bumblebees

12/07/2015

An international team of scientists demonstrated for the first time that due to climate change, bumblebee species in Europe and North America fail to relocate, lose distribution areas in the south and even disappear in some regions due to rapid global warming on a continental scale.

"It's happening right now, but in reality the decline started decades ago"Commented to the Scientific Information and News Service (SINC), Jeremy Kerr, a researcher in the Department of Biology at the University of Ottawa and lead author of the study.

While many species, such as butterflies, migrate north to cooler environments, to survive the rising temperatures, the bumblebee species of Europe and North America remain in the south.

SINC reported that to demonstrate how climate change affects these insects, Kerr and his colleagues developed a 423.00 database of geolocated observations (compiled from private collections and museums) of 67 bumblebee species from Europe and North America between 2001 and 2010.

In the study, the researchers also compared the changes of northward displacements of bee species of the last decades with the activity of bumblebees from 1901 to 1974, when the weather was colder.

The results of the research -published in Science- showed that bumblebees have not moved northward in recent decades. Moreover, during the same period, these pollinators disappeared from the southernmost and warmest areas, because they could not move towards colder habitats.

"We can not see general trends showing that bumblebees are overcoming rapid warming"Kerr told SINC, who pointed out that other factors such as land use and pesticides are not significant factors that contribute to the reduction of their populations.

While the study does not predict the time when some species of bumblebee will disappear, Kerr assured the publication that "What we do know with certainty is that many species of bumblebees are already on the verge of extinction. This is the case of the species Bombus affinis".

For the researcher, some species may already be extinct, given that "they have not been seen for a while".

"In the case of many species, they will face a real risk of global extinction in the coming decades if current trends are maintained"Warned Kerr.

For the expert, the problem is that the bumblebees have evolved in cold conditions, and seem to have enough problems with the heat.

Further, "we have found a sign that this is really happening in an evolutionary sense: a close relative of bumblebee species shares tolerances similar to temperatures"Said the scientist who indicated that there is a new biological mechanism that explains how species respond to changes based on their evolutionary past.

Source: Fruit Portal