Insect species that prefer crops prosper while majority decline

phys.org | 3/27/2019 | Staff
moemajor (Posted by) Level 3
Click For Photo: https://3c1703fe8d.site.internapcdn.net/newman/gfx/news/hires/2019/insectspecie.jpg

Many species of flower-visiting insect are in trouble in Britain, according to a new report from the Centre for Ecology and Hydrology (CEH) near Oxford, which drew on almost 750,000 observations of insects between 1980 and 2013. The study used population records of 353 wild bee and hoverfly species over large areas of Great Britain to show that one third of these pollinating species declined in range during this time.

Most of these losses were in species that were already relatively rare. Some big losers were the red-shanked carder bee, the smooth-gastered furrow bee and the large shaggy bee, all of which had vanished from around half of their previous locations in 1980.

Report - Species - Bee - Hoverfly - %

However, the same report also found that other species of bee and hoverfly, about 10% of the total, actually increased. Some of these, like the ashy mining bee and the lobe-spurred furrow bee, are pollinators of field crops like oilseed rape. These two species increased their ranges five-fold during the same period, suggesting that crop-specialist species are thriving at the expense of most others.

The other winners were actually invaders. The ivy bee – most often seen on the plant of the same name – only colonised mainland Britain in 2001 and the range over which it can be found has been expanding by 16% every year since. Despite what may appear to be a mixed bag, the overall diversity of British pollinator species has fallen steadily since 1980.

Insects

Why do we need insects?

The new study underlines the already alarming downward trend in insect numbers seen in several other studies conducted in the UK, Germany and Central America. In February 2019, a report claimed that current rates of decline might lead to "the extinction of 40% of the world's insect species over the next few decades". This almost apocalyptic claim was...
(Excerpt) Read more at: phys.org
Wake Up To Breaking News!
Sign In or Register to comment.

Welcome to Long Room!

Where The World Finds Its News!