Bees Need Food Up to a Month Earlier than Provided by Rcommended Pollinator Plants
New research from the Universities of Oxford and Exeter has revealed that plant species recommended as 'pollinator friendly'* in Europe begin flowering up to a month too late in the spring to effectively contribute to bee conservation. This 'hungry gap' results in low colony survival and low production of queens for the following year. The results showed that pollen and nectar availability during the early colony founding stage is a critical, and previously under-appreciated, factor in bee colony success. This approach focuses on existing hedgerows in agricultural land and doesn't reduce farm cropping area, so can appeal to land managers whilst also providing important conservation outcomes for pollinators.
The researchers explored when during the year bumblebee food (pollen and nectar) demand is highest, how colony survival is impacted by periods of food scarcity, how food requirements relate to seasonal changes in colony composition (numbers of adults, eggs, larvae, and pupae), and how availability of early spring-blooming plants affects colony survival and queen production. The colony's demand for nectar and pollen is driven mainly by the number of larvae rather than the number of adult workers.
Despite years of pollinator planting and conservation initiatives, pollinators are still in decline around the world. Very early spring flowers are likely to increase bee colony survival and queen production, contributing towards halting and reversing this decline. 'Bee colony success' is defined as the bee colony surviving until the end of the season and producing new queens for the following season.