Monday, 24 June 2019

Moreton Pinkney: 14th year of Breeding Bird Survey

I completed my fourteenth annual BTO Breeding Bird Survey last Saturday.  My survey square is just to the west of Moreton Pinkney in south Northamptonshire.  The land is mostly agricultural - predominantly sheep grazed pasture with a single arable field.  A disused railway line runs across the northern part of the square, as does a small tributary of the river Cherwell.
Early morning sun on the transect route
The highlight of this particular visit was a fine male Redstart that perched up on the top of a hedge and made a couple of short flights before moving on across the field and disappearing. Presumably this bird is already on migration back southwards. This is very much a first for my BBS survey visits - Redstart is a scarce passage migrant through our area (though they formerly bred) and July and August are the best months to catch up with them locally.
A male Redstart photographed in Wales last May
There are quite a few species I have only seen once during these surveys, others include Wheatear, Hobby, Fieldfare, Marsh Tit, Sand Martin, Tufted Duck, Little Egret and, perhaps most surprisingly, Sparrowhawk. In total I've recorded 72 species with an average of 41.5 species per year (across the two counts).
Many species have been remarkably consistent over the years, appearing each year in roughly similar numbers, but a few have shown declines and increases.
The two that stand out as doing quite well in recent years are Wren and Blackcap:
Male Blackcap singing
On the minus side, Chaffinch are not doing so well and Tree Sparrows have gone.  There are still a few Tree Sparrows not too far away so it is possible they may re-colonise.
The decline in Chaffinches and Tree Sparrows is very much in line with trends across the BOS area reported last year in Bird Trends in the Heart of England 1977-2016.  Between 1993 and 2015, Chaffinch declined by 30% and Tree Sparrow by 67%.
For the same period, the trend across the whole of England shown by The Breeding Bird Survey 2018 was down for Chaffinch (-18%) but up for Tree Sparrow (63%).  The latter seems to be doing well further north.  In our area Chaffinches are a common bird of farmland habitats, as well as woodlands and gardens, and this may explain why it is declining more here than elsewhere.  In most parts of the country the Chaffinch is a woodland bird and is regarded as a woodland generalist species, a group which are generally faring quite well.