Tuesday 3 November 2015

A new winter roost for Jackdaws and other corvids appears.

This year, as the bird breeding season came to an end, I noticed that as evening approached Jackdaws were beginning to congregate in the trees in the field behind my house. In the morning as it got light I heard them awaken and begin to fly off for a day's feeding and other non-breeding season activities hence I thought a new winter roost had begun somewhere nearby. There is a large, well established, Jackdaw and other corvid (Carrion Crow  and perhaps Magpies) roost at Baddeley Green. Previous counts indicate it has between 200 and 400 birds. It can be observed from the Caldon Canal towpath near Heakley Hall Farm and is located at map ref. SJ901 517. I have watched this roost for the past threee years and presumably it is older than that. I have written about it here. And I have mentioned another nearby one here.

The new one is in a plantation of mixed conifer and deciduous trees that were planted only a year or so before I moved to Endon twelve years ago. At that time the trees would have been too short to provide any cover for a roost, however now they are at least 3 metres tall, probably more. And, as some will have foliage all year round they will provide some shelter for the birds during harsh winter nights. Whether this new roost is a smaller one that I failed to notice before (though, as I say, it seems unlikely that it is more that five years old as the trees would have been too small then) that has grown into something more noticable, or that it is has freshly established this year I cannot be sure. Also, I wonder if it is comprised of birds that have previously been overwintering at one of the other nearby roosts and have split off the for this new one - again I do not know. Also, does it mean that the local Jackdaw population is growing so that a new roost is required to accomodate all the birds. Again I do not know. According to the British Trust for Ornithology's Bird Atlas 2007 - 2011 (published 2013) over most of the Britsh Isles breeding success for Jackdaws has been increasing over the past few years. Assuming %age mortality rate has stayed the same then the population of Jackdaws living around Endon could be increasing, which may help explain the necessity for an extra roost. Alternatively the other roosts may be less favourable for some reason and so birds from those have decided to find a new place to spend the winter nights. I will have to go along to the Baddeley Green one and see if it looks like there are fewer birds this year. Though, as it is very difficult to get an accurate count, I am not sure that this would help me to come to any conclusions. And, of course I don't know what is happening at other roosts that I either don't know about, or have never counted.

A futher point is that Jackdaws nest in the chimneys in the houses in my street, at least in the ones they can access. Some houses, including mine, have their chimneys capped to prevent them geting in. A few years ago a pair of Jackdaws investigated a Tawny Owl nest box I have installed on a tree in my garden; I dont think they actually produced a brood. So there is a breeding colony of Jackdaws close to this new roost.

Anyway, here are some photos taken on the evening of 03.11.2015 at about 16:40. The roost is visible from the Caldon Canal towpath beside the fields behind Post Bridge Cottage Farm and is actually on land belonging to Kypersley Farm (SJ931 528).

A pre-roost congregation arriving in a row of trees near the main roost.

Close up of photo above.

Jackdaws arriving at the main winter roost sight - you can just see that they are in paris as the males are guarding their mates - as is the usual behaviour for this species at this time of year (Jackdaws pair for life). 

Something disturbed the roost and this is hundred or so birds disturbed  flying up from the tree tops. this is typical behaviour, it takes quite a while for the birds to finally settle down for the night - perhaps an hour. 


Another temporary gathering area, before finally entering the trees.


The plantation where the roost is located. 



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  1. Wendy GREAT BLOG AND REPORT have left a Comment on Facebook

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