Cherry pollinators fest!

It was a warm, sunny afternoon and the cherry was at full bloom (three weeks earlier than last year), attracting a menagerie of bees, butterflies, queen wasps and flies. I did saw a honeybee, but I think even without this species, the cherry would be fully pollinated given the number and diversity of insects on it.

 Several bees were firsts for the year, including Bombus lapidarius, B. pascuorum and Melecta albifrons. I saw the first male red mining bee yesterday but they seemed to be everywhere today.

Bombus lapidarius queen 

Anthophora plumipes female

Queen wasp grooming

Possibly a dronefly

Male Osmia bicornis

and a Peacock also settled repeatedly on the blossom to feed

A small shining metallic wasp fell on the small pond and was rescued.

The first water beetle in the Victorian bath that makes our mini pond, awaiting ID.

Melecta albifrons, a cuckoo bee that parasitises A. plumipes, feeding on Muscari

 Melecta albifrons,  resting on a daffodil

And finally, a shot of a Red Mason Bee patrolling the Muscari.

A wet bee on bluebells

Continuing with the rain theme. Here you have a shot I took earlier of a soaking wet Melecta albifrons, during a brief sunny spell. She was still alert enough to offer me her middle leg (a defensive behaviour of bees and bumblebees) when I touched her.

Red Mason bee male checking out Melecta

A Melecta albifrons male has been feeding lazily on the Erysimum in the afternoon a sunny day.  Clambering over the flowers, not bothering to fly, this cleptoparasitic bee behaves in a very different way to its host: the buzzing, hovering, always alert Anthophora plumipes. Red Mason bee (Osmia rufa) males are patrolling the flowers and they check everything vaguely looking like a Red Mason bee female. With their contact, they scare away females A. plumipes - which I guess feel harassed like they do when their own males jump on them. A male Osmia rufa sees the Melecta and jumps on it. Just a quick contact, presumably chemical cues are checked and if not right, the bee flies away. The Melecta stays on. And when I check the camera, I am thrilled I got the shot!

Melecta albifrons male (photos 26/03/2012). They are handsome bees.

Melecta, a cleptoparasitic bee

The plum tree started flowering last week and today it was buzzing with bees. I counted six species, Bombus terrestris and lapidarius queens, Anthophora plumipes males and females, Andrena fulva, with males actively patrolling the branches, and the first males Osmia rufa of the year. Later, a black bee with white and grey hair patches and dark wings turned up. It was Melecta albifrons, a cleptoparasite of A. plumipes. I haven't found much information on M. albifrons so the following life history account mainly comes from a study on the American species, Melecta separata. Melecta females parasitise Anthophora species that nest communally. They explore their host's nesting aggregations in search of finished nests. A female, upon finding a nest will start digging and breaking open the sealed entrance. Then she will lay an egg on the roof of the cell, seal the cell and replug the nest. Anthophora females usually attack the cuckoo bee, but she either flies away or if inside the nest it defends herself with her sting. The Melecta larva hatches a day earlier than the Anthophora's and is very mobile. They pierce and drain the Anthophora egg and any other Melecta eggs that she finds in the cell with their long sickle-shaped mandibles. Only one Melecta larvae survives, as if two are born at the same time one will kill the other. The larvae then feeds on the syrupy mixture of pollen and nectar intended for the Anthophora larvae. Subsequent larval stages lack the long mandibles of the first stage. The following year a Melecta will emerge from the cell, having consumed the food intended for Anthophora grubs. In a M. separata nesting aggregation 20% of the nests were parasitized.
The Melecta albifrons visiting my plum showed a very different behaviour from other bees, sluggish, like she didn't want to fly too much, climbing over the flowers to reach each of them and feeding showing a very long tongue. The bee stayed for quite a while feeding on the plum flowers. M. albifrons has a very similar distribution to its host in Britain (click here for distribution map), reaching up to the Yorkshire Wolds in the north. Its peak flight period is a few weeks after the emergence of the host, and flies from April to early June. Given that it doesn't need to collect pollen for provisioning its brood, the bee is not fussy about what flowers to visit, and tends to fly at short daily periods - the warmest - as they are less endothermic than their Anthophora hosts, as shown in the figure below.

References
Thorp, R. (1969). Ecology and Behavior of Melecta separata callura (Hymenoptera: Anthophoridae). American Midland Naturalist, 82 (2) DOI: 10.2307/2423782
P. G. Willmer and G. N. Stone (2004). Behavioral, Ecological, and Physiological Determinants of the Activity Patterns of Bees. Advances in the Study of Behavior, 34 , 347-466 : doi:10.1016/S0065-3454(04)34009-X

Grape Hyacinth visitors

Many nectar-feeding insects prefer to use abundant floral resources. That is, a plant is much more frequently visited when there is a large clump of the species together or it flowers profusely, just because the insect has to travel less to obtain the same amount of energy. I have experienced this first hand in my garden with Grape Hyacinth (Muscari armeniacum) an early flowering bulb with clusters of deep blue flowers at the top of a spike. This year I have several large drifts of this species, which has been flowering for the last month or so and this has been rewarded by an unusually high diversity in the species visiting the flowers. Here is a selection of photos taken in the last few days on this plant.

Anthophora plumipes female loaded with yellow pollen and feeding on the flowers

Anthophora plumipes male, leaving the flowers with his tongue still extended

A male Red Mason Bee (Osmia rufa) sunbathing on a stone next to a Muscari clump. The first males of the year appeared today and I have watched them feeding and patrolling the plants, making sure they weren't missing any of the females. The males kept checking the Anthophoras.

A Peacock visiting the flowers. Grape hyacinths are also visited by Commas and Small Tortoiseshells (see here for photos)

This scruffy-looking dark bee with white tufts of hair is Melecta albifrons, the cleptoparasite bee (cuckoo bee) of Anthophora plumipes.

I have got no photos but a couple of days ago I saw an Andrena fulva and a queen Bombus pascuorum (both first of the year) visiting Muscari in my garden.

UPDATE 11/04/10

Today a queen Bombus terrestris visited the Muscari patch and I managed to get a shot of the first Osmia rufa of the year feeding on it as well.

UPDATE 17/04/10

A Green-Veined butterfly fed on the Muscari patch.