Reed Bed Blues

Been a difficult and disapointing month for our Bearded Tit and Reed Warbler RAS study at Leighton Moss. Ringing has proved difficult due to the poor weather but the Bearded Tit population appears to be well down . In June 2014 we caught 65 Bearded Tits of which 54 were juveniles, this year with admittedly less effort we have only caught 7 birds of which only 3 are juveniles.

Reed Warblers  are also down, in June last year we caught  115 , this year only 58. Part of the decline  is due to  the late fledging . We caught the first juveniles(2) this morning 10 days later than in 2014. The highlight of this mornings catch was a Reed Warbler in its 8th year, ringed as a juvenile in 2013 it had not been re-trapped until this morning. It is our 8th oldest Reed Warbler, the oldest was just short of 10 years.

Blue Tits are incidental to our study but they to are well down,34 last year almost all juveniles this year only 5 and not one juvenile. this fits in well with our nest box studies which reveal the lowest productivity since we recorded nest records on IPMR in 2001.

Some of these declines are due to less effort due to poor ringing weather. Last year we netted on 13 occasions compared with 9 this year. But low productivty brought about by the poor spring weather must be the main reason. Lets hope for a more productive July.
John

Nest Box Blues

Its certainly been a disappointing season for the tits in my nest boxes. I study 5 schemes spread through woods from the coast, through the willow scrub of Leighton Moss to the Oak woods of the Lune valley. I have compared the results for this year with 2014 which was an excellent year. In total this year I had boxes occupied by  58 Blue Tits and 53 Great Tits, compared with 60  Blue Tits and 71 Great Tits in 2014.

Total failures due to predation, desertion or the young dying increased markedly this year. In 2014 total failures was only 10% in Blue Tits and 15 5% in Great Tits . This year this has increased to 40% and 53 % respectively . The increase has been mainly in the whole brood of  chicks dying usually a few days after hatching or to desertion in the egg stage.

Brood size at ringing was 8.5 in Blue Tits in 2014 but only 6.2 this year. Great Tits declined from 8.5 in 2014 to just 4.4 this year.

We had a most welcome increase in Pied Flycatchers with 26 occupied boxes compared to 16 in 2014. Total losses though have risen from just 6% in 2014 to 41% this year. This was due mainly to predation (probably weasel) in the higher section of the main wood. The only losses of young were of three nests in an alder wood. Brood size was similar with 6.6 in 2014 and 6.3 this year.

This years poor results  must be due to the cool wet spring  producing a decline in caterpillar numbers especially early in the season when most of the losses occurred.

John 

 

A remarkable evening's ringing

As part of North Lancs Ringing Group's Sand martin Retrapping Adults for Survival (RAS) we are regularly catch Sand martins ringed in the UK and France.  Consequently the first two retraps in a recent visit being from the UK (Lune valley) and a bird from France were of no surprise. The next bird had a ring had an address of 'Icona, Madrid' which is our 9th from the main Spanish ringing scheme.  Amazingly the fourth retrap to be caught was carrying a ring was addressed 'San Sebastian, Aranzadi'.  This is the first Sand martin we have caught from the Basque ringing scheme in Spain and only the second bird the group has caught from it (the first being a Reed Warbler in 2010 near Heysham).

While it is always nice to catch birds from elsewhere the RAS project is all about returning birds to their breeding sites.  As I have said many times it is no surprise that Sand martins from the Lune go through France (in fact, it would be a surprise if one did not).  Spain, again is no surprise, however some Sand Martins do go to Africa via Italy.

So far this year NLRG has retrapped around 100 adults from previous years in two colonies with around 450 pairs. The oldest bird was originally ringed in 2010 as an adult with several captures since.  For a Sand martin this is getting to be a good old age.

Two more major colonies are much further behind in their breeding cycles so are yet to be visited.

As always, many thanks to everyone who makes this project possible.

A Unique Redwing ?

Recent recoveries from the Ringing Office included the Group's first Redwing in Iceland. This bird was ringed by Mark on the edge of Bowland on Boxing Day 2014 and found dead in cold weather in SE Iceland on 26 April this year. Whats unique about that? Well its the Group's first passerine to be reported from Iceland but the interesting question is, was it one of the Icelandic race coburni? The Migration Atlas (2002) says that the Icelandic race winters exclusively in Ireland and  Northern Scotland and there were no ringing recoveries of this race in England or Wales so this bird may be one of the first. However the timing of the recovery does not rule out vagrant spring passage of the continental race iliacus.

In total the group has ringed 2733 Redwing most of them at winter roosts. The map below shows the recoveries of this wintering thrush. The black spots are birds reported in the same winter as ringing showing that some birds move to Ireland and France in  severe winters. The red dots are birds reported in subsequent winters proving conclusively that  birds can change their wintering areas from winter to winter. Not a good idea really as all the southern European birds and the one in Azerbaijan were shot!

John