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Post Info TOPIC: Species in Focus - Jay.


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RE: Species in Focus - Jay.


Jays in Southern Cemetery yesterday seemed to collecting food and flying off - presumably back to a nest site but I couldn't hang around as I was doing the BBS.

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Not defeatism as such. They are 10x harder to confirm breeding than Blue Tit say, so they are bound to be slightly more under-recorded relitively speaking.
I'll be putting in a bit of extra effort to confirm Jay no doubt Steve.

Have fun this weekend!
Henry.

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Not showing signs of defeatism are you, Henry?

As Bill suggests, all our other evidence tells us that Jays have increased in number (and distribution?) since the last atlas - mainly due to the maturing of trees planted in country park areas in the 70s & 80s.

There is no evidence that we are doing less fieldwork than was done for Breeding Birds in Greater Manchester and surely bird observation skills haven't deteriorated?

Can't think of a better way of proving breeding than by following Bill's excellent tips.

Steve

PS I note that you have now logged well over 4000 atlas records, Henry

I'll put aside most of this weekend for checking them!

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Steve "Make your birdwatching count!"


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Certainly is a shy species in the breeding season Bill. I know that most tetrads in my area have a pair or two but confirming them is another matter. This will surely be an under-recorded species in the local atlas.
Henry.

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At the time of our last atlas, it was written that "although the Jay is moderately well distributed it is not abundant; most of the occupied tetrads only having one or two pairs. Also there is no evidence that this has changed significantly in the last hundred years". Just to provide a further bit of information, it then occupied 124 tetrads, with breeding confirmed in 69 of these. So the big question is, has this species expanded its range and increased in numbers since our last atlas? Anecdotal evidence might suggest that it has but data received for the current atlas project, up to and including the end of the 2010 breeding season, leaves any conclusions still pretty much up in the air. At the end of the third breeding season it had been recorded as a confirmed breeding species in just 37 tetrads, which is only 54% of the BBGM figure. So has this species really declined since BBGM or are we just missing those vital signals and sightings that would allow us to confirm breeding?

The Jay is probably the shyest member of the crow family and as a consequence is likely to be the most challenging of all of the corvids for atlas field birders to confirm breeding for. Still, which of us wants bird watching to be easy and straightforward? Most birders like to be tested - so if we become aware of the regular presence of a pair of Jays in suitable territory this breeding season, let's make it our mission to try and follow their progress and see if we can confirm breeding for a good few more tetrads for our atlas this summer.

A review of the data from the first three years of our current atlas project reveals that over two-thirds of confirmed breeding records for this species were for sightings of adults with fledged, dependent young (code FL). So would some information that might point towards when is the best time to look out for these family parties be of some help? According to the BTO Nest Record Scheme data the average date for the laying of the first egg is around 8th May and the average clutch size is 5 eggs. Incubation begins with the second to fourth egg and takes between 16 to 19 days and nestlings fledge after a further 19 to 23 days. This would appear to make mid June as the optimum time to start looking out for Jay family parties. So do any of these time scales appear to stack up with our own records? Well yes, surprisingly they do! There were several records of family parties of Jay, including recently fledged young, on our very own GM sightings forum from mid-June onwards last summer. Additionally, in the first three years of our current atlas those FL coded records were noted between the following dates:-

In 2008 - from 20th June to 27th July.

In 2009 - from 7th June to 20th July.

In 2010 - from 11th June to 30th July.

Incidentally, approximately 35% of these FL coded records were from June and 65% from July.


Young cease to be fed by parents at 6 to 8 weeks and this information taken in conjunction with the above mentioned dates appears to give us roughly about a month and a half in which to locate these elusive family parties. It now sounds so incredibly simple to be able to confirm breeding for Jay doesn't it! Such a pity it's not!

Once again the best of luck with your bird watching and many thanks for your help.


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