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. Bees collect pollen and nectar for their food    Nectar is converted into honey in the hive, whilst the pollen is converted into beebread / 'bee pollen' .  Read more...

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...

Flowers have various ways of tempting pollinating insects to visit them.  Indeed, some have very complex mechanisms to promote pollination and fertilisation, for example, the bee orchid.  In order to attract pollinating bees, the orchid has evolved “bee-look-alike” flowers.  These draw the bees in with the “promise of sex”.  They attempt to mate with the flower, landing on the velvety lip of the flower and pollen is transferred.  The bee leaves ‘frustrated’.  However, the right species of bee doesn't live in the U.K., so here bee orchids self-pollinate. Read more...

Different species of bumblebees make their nests in different places (using feathers, hair, dried moss or grass or materials for loft insulation). White tailed bumblebees.       May be found under the floor of garden sheds Buff tailed bumblebees.           May use air bricks and nest in the cavity walls of house Early bumblebees.                     Often use old birds’ nests in trees Carder bees                                 May use grass tussocks, dry leaves e.g. Under bramble thickets Tree bumblebees                        Make use of holes in tree trunk Wherever the nest is, the queen collects and forms a ball of the insulation material in a central space. https://www.youtube.com/watch?v=GCYUTRw-VZI Then, the queen constructs a ‘cup’ of wax.   This wax is produced by glands along the body, and molded by the legs and mouthparts (mandibles). Once formed, the wax ‘cup’ is filled with honey (essentially concentrated nectar). In addition to foraging for nectar, the queen will collect pollen which, with the addition of some nectar /honey, is fashioned into a small, pea-sized ‘ball’. The ‘ball’ is finally covered in a layer of wax. If the queen has fed well, then her ovaries will have developed and will be ready to lay eggs. The eggs are fertilised as they pass out of the body, using sperm stored from the mating that happened the previous year. A batch of eggs (usually 16) is placed inside the ‘pollen ball’, which is again sealed up with wax. The eggs are ‘sausage shape’ and cream in colour. Once inside the pollen ball, the bumblebee eggs are incubated - rather like the care extended to birds’ eggs.   They are kept warm by heat energy generated by the queen – who shivers and her muscles generate heat energy to warm the eggs. Shivering uses up energy at a prodigious rate, so the queen makes use of the nectar/honey store.   However, this does not last so the queen has to leave the nest (in search of nectar); but the eggs cannot be left for long or they will cool and development will slow (or cease). If kept at the right temperature, the eggs will produce grubs or larvae in about four days. The larval stage of all insects is a feeding stage – in which the animal builds up cells and tissues; and grows. In order to grow though, the larva / grub has to shed its skin / cuticle (this moulting is known as ecdysis) and the new one (formed beneath the old one) allows for expansion.  Moulting happens three times within 12 / 14 days and the grubs increase in size substantially. Next, the grub / larvae spins a cocoon from a protein thread. Within this, pupation and metamorphosis occurs. The tissues of the larva are completely remodeled – to form antennae, eyes, legs, distinct internal organs. This transformation takes about two weeks – at the end of which time, a recognizable (but white) bee emerges. To be continued .......

Nectar is a sugar-rich liquid produced by special glands on a plant.  These glands are usually associated with the flowers - but not always.  Floral nectaries are usually found at the base of the petals so that a visiting insect picks up or deposits pollen whilst collecting the nectar; thus, 'helping' the plant to reproduce / set seed.   Common pollinators are bees, bumblebees, wasps, moths, butterflies and hummingbirds;  less common pollinators are flies, ants, possums and bats. Read more...

Bees are (usually) frequent visitors to our gardens.  Gardening catalogues and websites are ‘always’ extolling the virtues of particular flowers / plants in terms of attracting insect visitors to our gardens.  These insect visitors are important pollinators – not just for garden flowers, but also for fruit trees and other soft fruits.  But is there any evidence about the ‘best flowers’ to plant for insect visitors – other than “opinion and general  experience”. Now some research on this has been done by the Department of Apiculture at the University of Sussex.   The Department and Professor Ratnieks (which have featured in the woodland blog before) are involved in “The Sussex Plan for Honey Bee Health and Well being”. Read more...