Wind Chill Causes Numb Fingers

A Twite catching session this morning saw John Mason and myself on the North Harbour Wall at around 07.15 to set up the whoosh net.  Although the temperature was just above freezing, the 15 mph wind made it feel extremely cold.

A single net launch resulted in a catch of 39 Twite (27 retrap, 1 control & 11 new birds) and two new plus one retrap Goldfinch. The retrapped Twite were all recently ringed except for two - all were recorded but not processed in view of the conditions.  The control bird was wearing a BTO metal ring on the right leg, but no colour rings.  Two birds with metal only rings have been here for a while now and we have been hoping to catch them.

Following this burst of activity it was decided, in view of the lack of any feeling in the fingers and toes and the light snow flakes falling, to retire to the Nature Reserve hut to recover.

It is known that Machrihanish bird obs. did ring a few birds with metal only in autumn 2012 so we were half expecting these two to be part of that catch, although the ring series was not similar to others they used in that period .

Machrihanish have been contacted by email and we await a reply.


ajd  

Blue Tit versus Coal Tit

One of the fascinations of ringing at a site over the years is that you have an insight into the changes in bird populations. I operate a small broad leaved woodland  feeding station at which ring I ring  on ca 20 occasions each winter and average around 700 birds per winter. This winter has been extraordinary for the numbers of Coal Tits I have caught compared with the number of Blue Tits. This sent me looking back through my records.

I  analyzed the catches in three year periods and worked out the percentage of Coal Tits in the catches the results are as follows-

04-06         24%

07-09         44%

10-12         49%

This means that although up to this winter the numbers of blue tits has been reasonably stable, Coal Tits have increased quite dramatically. In fact for this winter so far for the first time the numbers of Coal Tits have exceeded the number of Blue Tits with 140 Coal Tits and the lowest number of Blue Tits at 96. This gives the highest percentage yet of 60% Coal Tits in the catch.

Why should this be? Firstly, Blue Tits had a very poor breeding season in the cold and wet spring of 2012. Coal Tits obviously did better. But the long term increase in Coal Tits in this area is probably linked to the maturing of the many conifer plantations  to the north of us. I also get the general impression that Coal tits are breeding in larger numbers in mixed and broad-leaved woodlands. They were certainly irrupting last autumn as is so well shown by the ringing totals from another of our sites Heysham B.O. where 474 have been ringed in 2012 compared to just 80 in 2011. It  will be interesting to see what any recoveries we get shows.

John

A Review of Ringing in 2012

I am sure that most ringers will agree that 2012 has been one of the most difficult years, with the wet and windy weather restricting activities. The poor weather though does also seem to have had  a detrimental effect  on the productivity of many species and these two factors are  certainly reflected in our ringing totals.

Our final total of 10,251 new birds is just over 4,000 down on 2011.   The species with the largest decline was Sand Martins where we  undertake a Re-trapping Adults for Survival (RAS) project on the colonies  along the River Lune. From 2140 last year to just 462 in 2012. The poor weather was mainly to blame, not  only did it cause problems on the evenings we planned to go out but with so much rain river levels were high and we could not access some of the colonies and some were completely flooded out.  Counts of the nest holes though showed a decline from last years record population. By contrast Swallows were up from  556  to 1400 due to the formation of a workable reed bed roost at Middleton Nature Reserve.

Turning to the warblers, all species except Willow Warbler were well down. Reed Warblers, on which we run an RAS declined from 971 to 649, Sedge Warbler from 479 to 243 Whitethroat from 158 to 70, Grasshopper Warbler from 46 to just 11 and Blackcap from 163 to 102. Suggesting poor productivity in all these species. Willow Warbler at 507 declined only slightly, past recoveries suggest that most of our passage Willow Warblers orginate in Scotland where the weather was apparently better than ours.

Of the resident species all the tits were well down  with the marked exception of Coal Tit which at 459 was 108 up. Coal Tits nest earlier than the other tits so they possibly escaped the  poor weather and perhaps their coniferous habitat provided better conditions. Support for this latter view comes from another coniferous breeder the Goldcrest  which increased from 185 to 314.All the finches except Goldfinch were down.

Perhaps the best evidence for poor productivity comes from the nestling ringing in our nest boxes. A project where effort was  the same in both years. Blue tit nestlings  declined from 908 to 505 this year. Great Tits from 507 to 368 and Nuthatch from 69 to 39. The later nesting Pied Flycatchers did better going from 515 to 451.

So rather a dissapointing year, let's hope that 2013 brings better things.

John