The decline of bumblebees and other pollinators has been noted in the woodlands blog on several occasions; they play a key role in the pollination of many crops that we rely upon.
Urban areas are now important habitats for bees, bumblebees and other pollinators as the world becomes increasingly urbanised, and patterns of land management have changed over the last century - with vast swathes of monocultures. Urban areas can offer a much greater selection of plant species. Cities can offer diversity to both long tongued and short tongued bumblebees (specialists and generalists respectively) by offering a rich choice of flowering plants. Specialist bumblebees have long tongues to probe deep into certain flowers, whereas short-tongued, generalist bumblebees can collect nectar / pollen from a variety of flowers. Read more...
Some 90% of the world's plants, including many food crops, rely on animals for pollination (as opposed to wind or even rarer water pollination). The contribution of honey bees and bumblebees to these pollination services is vital but they are at risk due to:
- the effects of disease,
- climate change
- effects of pesticides and
- habitat loss / destruction.
Whilst it is sometimes possible to help hives / colonies of the ‘domesticated’ honeybee suffering from parasites / disease, ‘helping’ wild populations is a much more difficult proposition. Read more...
Declining bee populations in Europe have caused alarm in recent years and the decline has been attributed to a multitude of factors / causes, for example :-
- Climate change
- Pesticides - especially neonicotinoids
- Varroa mites
Sound is part and parcel of life. The nervous system of animals are attuned to it; it serves to inform them of danger, of food, of mates etc. We do not think of plants are being sensitive to or responsive to sound - though some people are convinced that talking to plants helps them to grow better (this might be due to an enhanced level of carbon dioxide near to the plants). However, some recent studies by Professor Lilach Hadany (of Tel Aviv University) and her colleagues suggest that some plants can respond to certain sounds that bees produce. Read more...
Bumblebees and honeybees seem to be assailed from all sides - pesticides, parasites and viruses, habitat fragmentation, climate change all come into play. Now a study of honeybees in the North West (of the UK) suggests that there is a clear link between their immediate landscape and the quality of their diet.
Flower-visiting insects evolved in the Cretaceous Period (about 100 million years ago) - a time when the major flower groups (Monocotyledons and Dicotyledons) came into being. Flowers have a number of “ploys’ to encourage pollinators to visit them - for example, by their colour, scent, reflectance, size, outline, temperature, motion and nectar guides. The latter are markings or patterns on the petals and floral parts to guide bees, bumblebees or other pollinators towards the nectar and to encourage pollination. This link (click here) shows how a flower might appear to a bee or butterfly - due their sensitivity to U.V light. Read more...
It has been known for some time that bees and bumblebees are attracted to flowers by their colour(s), scent (volatile oils), shape, nectar and indeed electric fields (see recent post). However, it has now been shown that bumblebees can pick a plant on the basis of the nutritional content of its pollen.
Anthony Vaudo et al at the Centre for Pollinator Research (Penn State University) recorded the foraging patterns of bumblebees in defined outdoor areas, and then determined the chemical make-up (carbohydrate, protein and lipid levels) of the pollen from the different species present. They found that the bumblebees went for pollen with a high Protein:Lipid value. Read more...
Sadly, our air is polluted with many different chemicals from anthropogenic sources - particularly the burning of fuels. Many of these chemicals have been implicated as exacerbating a number of health conditions - notably heart disease, COPD (chronic obstructive pulmonary disease), stroke and lung cancer. Common pollutants are particulates (from diesel), ozone and nitrogen oxides. These pollutants not only affect us but also many different plants and animals.
Recent research at Penn State University has revealed that ozone interacts with plant scents (volatile oils) and degrades them. As a result the scents are less effective in attracting pollinators (bees and bumblebees) to the flowers. Read more...