Science

Wild bees and flowers both declining, survey finds

The diversity of bees and the flowers they pollinate have both declined significantly in Britain and the Netherlands over the last 25 years, researchers have found.

The diversity of bees and the flowers they pollinate have both declined significantly in Britain and the Netherlands over the last 25 years, researchers have found.

"We were shocked by the decline in plants as well as bees," the study's lead author, Koos Biesmeijer of the University of Leeds, said in a statement.

"If this pattern is replicated elsewhere, the 'pollinator services' we take for granted could be at risk. And with it the future for the plants we enjoy in our countryside."

The pollinators are essential for the reproduction of many wild flowers and crops.

While previous studies looked at only a few sites, Biesmeijer's team of professionals and volunteers compared records forhundreds of sites from before and after 1980.

Particular bees for particular flowers

Loss of bee diversity might not be a problem if a single species of bee could pollinate every flower species, but that's not the case, the researchers report in Friday's issue of the journal Science.

Overall, generalist pollinators are replacing a larger number of rarer, specialist pollinators.

"In Britain, pollinator species that were relatively rare in the past have tended to become rarer still, while the commoner species have become even more plentiful," said Stuart Roberts of the University of Reading.

"Even in insects, the rich get richer and the poor get poorer."

The scientists don't know if it's the bees or flowers that are disappearing first, but the declines parallel each other.

In Britain, there were declines in 70 per cent of the wildflowers that need insects for pollination, while wind-pollinated or self-pollinated plants stayed the same or increased.

The Netherlands showed a decline in plants that require bees for pollination, but not plants that can turn to other insect pollinators.

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