Earth_Island_Journal_-_Spring_2020

EARTH ISLAND JOURNAL • SPRING 2020 9

New research links climate change to bumblebee declines, particularly in warming southern areas like Mexico and Spain.

CALL OF THE WILD

Bad News

for Bees

The news keeps getting worse for insects. Colony collapse

disorder is wiping out honeybees. Habitat loss is decimating

UWVIZKP J]\\MZÆQM[ 7^MZITT QV[MK\ UI[[ Q[ LMKTQVQVO NZWU

Puerto Rico to Germany. Now, it seems, we have one more

bit of bad news to add to the list: As the climate warms,

bumblebees are struggling to hold on.

A new report published in ScienceÅVL[\PI\J]UJTMJMM

populations are facing steep declines in North America and

Europe. Researchers, who mapped where bumblebees used

to live compared to where they are now, found that the

likelihood of a site being occupied by the insects declined by

a striking 46 percent in North America and 17 percent in

Europe in less than a single generation.

“It was the weirdest thing ever,” Jeremy Kerr, a coauthor

of the report and a biologist at the University of Ottawa,

told Sierra magazine. "We were going over our numbers, and

we realized that actually what we were looking at over the

course of half a generation of humans was the progressive

mass extinction of a taxom ... I mean, it's an astonishing rate

of change.”

PMZM[MIZKPMZ[TWWSMLI\LQٺMZMV\J]UJTMJMM[XMKQM[

comparing bee observations between 1901 and 1974 with

those between 2000 and 2015, by which time the impacts of

climate change could be observed. They found bee declines

were most pronounced in warming southern areas like

Mexico and Spain that are experiencing higher temperatures

related to climate change, and where bumblebees are already

living at the edge of their temperature range.

“Bumblebees thrive in cool, temperate climates,” Dave

Goulson, bumblebee expert and a biologist at University of

Sussex, told Inside Climate News. “They are scarce in warmer

regions where they tend to overheat in hot weather. It seems

TQSMTa\PI\IZIXQLTa_IZUQVON]\]ZMKTQUI\MUIaJM\PMÅVIT

straw for many of them.”

What’s bad for bumblebees is also bad for a range of

plants, including both wild species and food crops like berries,

tomatoes, and squash. Bumblebees have a longer pollination

season than most other insects, beginning earlier in the spring

and continuing further into the fall, due to their tolerance for

KWWTMZKTQUI\M[IVLKIXIKQ\aNWZTWVOMZÆQOP\[

<PMZM[MIZKPMZ[PWXM\PMQZÅVLQVO_QTTQVNWZUJ]UJTMJMM

conservation work, which must include climate mitigation

measures as well as habitat preservation. They also believe

their methodology to predict extinction risk could be applied

to a wide range of other animals, including reptiles, birds,

and mammals.

"Predicting why bumblebees and other species are going

extinct in a time of rapid, human-caused climate change

KW]TLPMTX][XZM^MV\M`\QVK\QWVQV\PM\_MV\aÅZ[\KMV\]Zaº

Kerr says.

talking points

PH

OT

O^ J

AM

ES

JO

HN

ST

ON

E