July 2019

Yesterday I saw two swifts.  It is only the second time I have seen swifts this year, the worst year since we moved here.  Swifts are in serious decline as highlighted on BBC’s Springwatch recently.  They suggested that part of the reason for the lack of swifts this year has been bad weather in Spain that has delayed or interrupted their migration.  Another reason for their decline is the dramatic decline in the number of insects.  Swifts feed exclusively on flying insects and stay on the wing throughout their lives except for brief periods to mate and nest.  Martins and swallows also feed on the wing, but they do land to roost as well as to nest and mate.  Their ability to land may also allow them to pick off crawling insects to supplement their diet, something swifts cannot do as they have no claws that would enable them to grip a perch.  Another difference is that swifts tend to fly much higher than swallows or martins when they feed but it’s debatable whether that is a factor in their decline or not.  It will be a sad summer when swifts no longer reach the UK, and that summer doesn’t seem that far away.

I found out something interesting about the bee-wolf (Philanthus triangulum) recently.  The bee-wolf is a solitary wasp – solitary because it doesn’t form a colony like the more familiar social wasps that will ruin your picnic – and is one of a group called digger wasps.  It digs a long burrow in soft sandy soil and will dig brood chambers at intervals along the burrow.  It then goes out and catches honeybees which it paralyzes with its sting and then carries the bee back to its burrow.  It will do that three or four times for each chamber and will then lay a single egg in each chamber.  Note that the honeybees are only paralyzed, not dead because they stay fresher like that.  The egg then hatches and the larva feeds on the paralyzed honeybees – yes, it’s gruesome!  It has been estimated that a typical beewolf burrow will contain up to a hundred honeybees.

Bee-wolf - Philanthus triangulum

I have been reading about the relationships between insects and bacteria recently and how insects use bacteria to aid digestion, and about how bacteria affect the behaviour of insects.  The interesting thing about the bee-wolf is that it can exude a white paste from its antennae which contains a particular strain of bacteria.  The bee-wolf daubs this paste onto the roof of the burrow.  This has two purposes – firstly, it shows which way is out when the next generation emerges from their chambers the following year, and secondly, it passes on that same strain of bacteria to the next generation for daubing on to their burrows.  Bee-wolves are active from July to September and should you wish to see them in action, I can recommend the RSPB Nature Reserve at Dungeness.  There is an area of sandy soil on the right of the track about 50 yards before the visitor’s centre where you can see bee-wolves carrying their prey to their burrows and you can marvel at their strength and their gruesome lifestyle.  Don’t worry about being stung – they are only interested in bees.

Bee-wolf with prey -  you can just see the outline of the bee below the wasp

Incidentally, the bee-wolf used to be a rarity in Britain until the late 1980’s.  They have since expanded their range considerably and are now commonly seen throughout the south and east of the country.  They are common in continental Europe and are known to expand their range during long hot summers.  I guess I could bang on about global warming now but I won’t – maybe next month.

June 2019

As we walked back from the Village Hall recently, we saw a very large egg partly hidden in the grass by the entrance to the church.  There was no sign of any nesting activity, and no sign of any large birds anywhere.  The most likely parent is a greylag goose.  These have been seen flying over the area, and the distinctive thing about their eggs is that they are white when laid but gradually become stained as they age.  This egg was mostly white with some staining and has become more stained since we first saw it.  One theory is that geese could jettison their egg in flight for some reason, perhaps because the bird was ill or injured, or maybe just exhausted.  Apparently, the population of greylag geese in the south-east don’t migrate and are resident throughout the year, but it is possible that it could be from a bird that was returning from its Mediterranean wintering ground to more northerly breeding grounds in say Scotland.  I guess that it’s a mystery that will never be solved, the only certainty is that sadly, this particular egg won’t be hatched. 

I was delighted to see a red kite fly over the garden in the last day or two (mid-May), not least because it gave me a break from digging the garden as it meandered slowly past.  They are magnificent birds and the reintroduction of red kites to the UK has been very successful.  Starting in 1989, young birds were introduced, mostly from Spain, to the Chilterns and to Northern Scotland over a five year period.  Since then there have been several more reintroductions in the Midlands and in Northern England.  Though red kites are now seen regularly throughout the UK, the one that I saw may not have been from a reintroduced population, it could equally well have been a migrant from northern Europe which also has a thriving population of red kites.  Though they are raptors and will take live prey if they get the chance, they are mainly scavengers taking carrion and any other scraps they can find.

Barn Owl (Not the local one, this was seen in Norfolk)

Last year we saw a barn owl carrying prey over to a nest on the far side of the field at the back of the house, and eventually saw one fluffy fledgling sat out on a branch of the tree.  A couple of weeks ago, we saw the barn owl again (or maybe another one) carrying prey in the opposite direction towards Pannel Valley.  No doubt it has a young family to feed somewhere in that direction.  The breeding season is certainly in full swing at the moment and we have seen blackbird and sparrow parents feeding their chicks in the garden.  The sparrows have re-used the artificial house martin nest box I put up a couple of years ago, that has never been used by the martins.  The martins seem to prefer to refurbish their old mud nests, which they are doing at both the front and the back of the house.  The swallows seem to be investigating the carport for nesting, but it always takes them a long time to settle and start nest building.  As in previous years, there are three swallows involved.  We assume that this is a male, a female, and one of last year’s juveniles.  There seems to be no squabbling as between two rival males and so the third bird is probably a family member.  We also assume that it is the same pair that return each year, but that is unlikely as most swallows only survive for about four years, though some have been recorded up to eleven years old.

Swallow chicks from 2012