Friday, 21 August 2015

Plight of the Bumblebee 2: Commerce and conservation

B.lapidarius in my garden
When people talk about the vital importance of bees for pollination and agriculture, the only species that is usually thought about is the honeybee. For many crops however, both those grown in field and those in glasshouses, bumblebees and other wild bees are vastly more important. While honey bees are pretty generalist feeders, visiting many types of flower, they are not good at pollinating many species and are incapable of pollinating some crops at all, of which the Solanaceae (tomatoes, chilli peppers, aubergines etc.) are the most obvious. These require “buzz pollination”, where the bees vibrate the anthers to release pollen.  Other important crops which benefit from this type of pollinator rather than honey bees include blueberries, cranberries, and also kiwifruit. Even apples seem to be better pollinated by bumblebees that honeybees, as honey bees approach the flower in such a fashion that pollen is not efficiently moved from flower to flower. In addition, honeybees will not fly in cool or wet weather, which reflects their essentially tropical to subtropical origins. Bumblebees by contrast are adapted to cool climates, and will fly in cold weather or even in rain.

Tuesday, 11 August 2015

Plight of the Bumblebee Part 1: Lifecycle

B.terrestris worker
Aside from the honeybee, just about the only wild bee species most people in Britain are able to name are the large, furry bumblebees in the genus Bombus. With 24 species in the UK, and around 250 worldwide, they are a small but conspicuous minority of the several hundred species wild bee species in the UK. Aside from bumblebees and honeybees, the other species are all solitary, with a single female provisioning their nest, usually in a hole which may be excavated in the ground, wood, or simply a hollow stem.