Mr Wasp

This handsome beast is a male wasp, something not often seen.  He is easily identified from his enormous antennae and his long abdomen which has seven segments (compared with the female's six).  I presume the antennae help to locate the females by scent.

You will have realised by now that I am a fearless superhero but the truth is that male wasps don't sting.  Here are a couple of photos in a more natural setting.

We can tell from his face that this is a male common wasp (Vespula vulgaris).

Queen wasps are a familiar sight in the spring as they forage and chew wood before starting a new colony.  And worker wasps are very common, especially in early autumn as the colonies break up and the redundant workers go on the rampage, terrorising picnics and beehives.  This chart from BWARS compares the appearance of the three castes of Vespula vulgaris.

Late in the life of the social wasp colony the queen starts laying eggs that will produce males and new queens.  After mating the queens go off to hibernate until next spring while the males and the workers all die off.  The males spend their short lives flying, drinking nectar, and chasing females.  Sounds like a pretty good way to make a living.

Young blackcaps bite the dust

I have been very intrigued to watch these young blackcaps in the garden this week.  They were eating woody nightshade berries which are poisonous.

Immediately after eating the berries they were flying down to a patch of bare soil and picking up small bits of earth.  At first I wondered if they were looking for insects but it was clear they were swallowing the soil.

To prove what they are up to here are a couple of brief video clips, the first with a tree sparrow joining in.

I think the blackcaps are probably all juveniles although some have better developed feathers than others - possibly from first and second broods.  Juveniles and females aren't always easy to tell apart.

Soil eating is known as geophagy, literally earth swallowing, and is observed in many types of animal.  It is common behaviour in many herbivorous mammals as a way of providing essential minerals otherwise missing from their diet.  I found an interesting article by Jared Diamond reviewing reasons why birds (in his case parrots) might eat soil.  They include 1) to assuage hunger, 2) to help grind up swallowed food, 3) to buffer acidic or alkaline foods, 4) to counteract viruses or bacteria, 5) to provide essential minerals, and 6) to detoxify plant poisons.

Of these I wondered if the last is the explanation in these blackcaps.  Woody nightshade berries (Solanum dulcamara) are toxic and the other birds seem to avoid them.  Then I found this extract in a book called Birds and Berries by Barbara and David Snow.

So it seems that blackcaps deliberately seek out the woody nightshade berries.  I think the probable explanation for what I have seen is that the blackcaps are eating the poisonous fruit and then eating the soil as an antidote.  The question is why don't they just eat the blackcurrants, gooseberries and raspberries like the other birds do?  They must get something out of it.  Any comments will be welcome.

Bird of the week - Tree sparrow

The tree sparrow chicks in the last three nest boxes in the garden have fledged in this past week.  I think these were all third broods although it isn't always easy to keep track of what they are up to.

I noticed the sparrowhawk in yesterday's post has been hanging around in the kitchen garden this week - he must have known the chicks were about to fledge.  They were certainly making a lot of noise and they attracted attention from this woodpecker as well.

The chicks' first flight was as far as the fence where they sat and wondered what to do next.

I have been offering the sparrows red millet seed recently and they seem quite pleased with it.

The first chicks fledged at the end of May so they are now well able to look after themselves.

The newest chicks can fly to the feeder but can't feed themselves.

The sparrows are very keen on taking dust baths at this time of year.  It helps to remove parasites from their feathers.

The dust-bathing sparrows attracted a lot of interest.  They were watched in their baths by a very puzzled young blackcap,

a woodpigeon,

a robin,

and a rather suspicious young willow warbler.  It is a good job they are not shy.

Here is a brief video of a young sparrow trying out a dust bath yesterday, even though the soil isn't really dusty enough.

Tree sparrows are in trouble, having suffered a catastrophic decline in numbers in the 1970s and 1980s.  They are on the UK Red List because of population decline.

The picture is more promising when you look at BTO Garden BirdWatch data for the North East of England for recent years.  Tree sparrows moved into my garden in spring 2012 and have been here ever since. 

Tree sparrows are now largely absent from the south of the country and seem to prefer eastern parts of Northern England, Scotland and Ireland.

The tree sparrow is Passer montanus and in Thomas Bewick's time it was known as the mountain sparrow.  It is interesting that its distribution was very different in those days, almost the opposite of how it is now.  Bewick wrote

This is Bewick's illustration for A History of British Birds published in 1797.

The tree sparrow's call and song obviously aren't interesting enough for it to be included in the recordings at the British Library but you can hear it here.  It has also featured on the BBC Radio 4 Tweet of the Day as you can hear here.

The garden has been full of tree sparrows this week, great to see.

The hunter and the hunted

These photos were taken a few minutes apart in the kitchen garden, a male sparrowhawk and a very young dunnock.