Monday 29 June 2015

Hoverflies that mimic bumblebees

This large hoverfly is Volucella bombylans.  It exists in two forms, Volucella bombylans var. bombylans, a mimic of the red-tailed bumblebee (Bombus lapidarius) and Volucella bombylans var. plumata, a mimic of the white-tailed bumblebee (Bombus lucorum).  Batesian mimicry reduces the chance of the fly being predated by its resemblance to a bee.  The female hoverflies lay their eggs in the nest of social wasps and bumblebees where the larvae are scavengers, usually feeding on debris in the nest rather than on the host larvae.

This is Volucella bombylans var. bombylans.


And this is a red-tailed bumblebee worker.


This is Volucella bombylans var. plumata.


And this is a white-tailed bumblebee.

Another, less common hoverfly that mimics a bumblebee is Merodon equestris, the large narcissus fly.  Its larvae develop in daffodil bulbs.  The adult fly's colouring is quite variable - this male is perhaps a mimic of the common carder bee.  He was defending a patch of flowers against all comers, chasing off any bumblebee that tried to land.

This is a common carder bee.

For a well illustrated guide to hoverflies that mimic bumblebees (in Ireland) click here.

30 June 2015 update.  After posting the above yesterday I found this fly this morning at Banks' Pond.  I think it is a female hoverfly with an unusual colour form and the unfortunate name of Volucella bombylans var. haemorrhoidalis, perhaps mimicking an early bumblebee (Bombus pratorum).


And here is a male Bombus pratorum.

Saturday 27 June 2015

Bird of the week - Puffin

The puffin (Fratercula arctica) is everyone's favourite seabird.  There are 40,000 pairs on the Farne Islands.








This one looks either happy or bored.  The serrations inside the beak help it hold onto fish.





The puffin's favourite food is sand eels.  The record number in one beakful is 83!  Returning puffins fly back to land in groups to reduce the risk of attack from predatory gulls and skuas.



Puffins make their nests in burrows grouped in colonies.  The female lays a single egg and on fledging the chick leaves the nest for the first time at night.  It swims out to sea and does not return to land for two or three years.









Listen to the BBC Radio 4 Tweet of the Day on puffins here.

Thursday 25 June 2015

Ruby-tailed wasp

The first time I saw this tiny jewel-like wasp was when talking to Peter a couple of weeks ago by the gate to Banks' Pond.  It was only there for a moment and didn't keep still so I didn't get any useful photos.  This time when I stopped by on the off chance it (or another one) was there again, and it sat still for long enough to have its photo taken.





Ruby-tailed wasps are cuckoo wasps, parasites or kleptoparasites of solitary wasps and solitary bees - that is their larvae eat the larvae of the hosts or their food supply.  Chrysis ignita is the most common species but there are several others that are very similar.  It has an armoured body as protection against the defences of the host.  It parasitises mason bees and leaf-cutter bees as well as some solitary wasps.  On the same gate I saw this bee, a leaf-cutter I think but I haven't yet identified it - possibly Megachile centuncularis or M. versicolor.  It may well be the host species.

Tuesday 23 June 2015

Kittiwakes

The kittiwakes on the the Tyne Bridge were my bird of the week recently but most kittiwakes nest on cliffs.  There are over 4,000 pairs on the Farne Islands where these photos were taken.






Monday 22 June 2015

Orange-tailed mining bees

Orange-tailed mining bees (Andrena haemorrhoa) foraging on viburnum at Hidcote Manor.  It is interesting that there is no pollen on the bee's knees!




Saturday 20 June 2015

Bird of the week - Guillemot

A bird called William - guillemot is derived from Guillaume, French for William, although why William I don't know.  In North America the same bird is a common murre and its scientific name is Uria aalge.

The Farne Islands are home to over 25,000 pairs of guillemots in the summer.


A small percentage are bridled guillemots, that is they have spectacle-like markings around the eyes.

The guillemot looks dark brown and white when compared with the razorbill.

Female guillemots lay a single egg and brood it on the rock face as there is no nest.  The eggs are conical-shaped to minimise the risk of rolling off the edge and have a special self-cleaning waterproof surface.

Young guillemots are known as jumplings because their first move is to jump off the rocks into the water.  We saw only one jumpling last week.  Its feet look enormous - all the better for jumping with.

Listen to Sir David Attenborough's BBC Radio 4 Tweet of the Day on guillemots here.

Thursday 18 June 2015

Full circle

The arrival of the great spotted woodpecker chicks in the garden this week reminds me that it now just over a year since I started writing this blog. 





My first post on 14th June last year was on woodpeckers feeding their young.  Taking a good photo of the feeding is a challenge because the chick is usually sitting on the wrong branch, or the wrong tree or just out of view.  My luck was in this morning.  Considering the poor light under the trees on a cloudy windy day the photos aren't too bad.  It is interesting that most of the feeding seems to be done by the fathers.





Here is something I don't think I have ever seen before - both birds on the feeder.  And it happened twice this afternoon.





The chicks are quick learners and soon work out how to get onto the peanuts and feed themselves.