True Grit

The use by Bearded Tits of the grit trays at Leighton Moss have been exciting a lot of interest this year. I thought some back ground information on the development of the trays may be of interest along with our findings from colour ringing the birds.
For many year Bearded Tits used to grit on the gravel paths. The rather poor photo shows a shot taken c 1993 with 22 bearded tits all gritting on the paths. In c 1996 I had the idea to provide grit trays and they have been used ever since and use of the paths has stopped. Birds gritting on the path were subject to a lot of disturbance but the present arrangement allows lots of people to see (and photograph) these super birds.
Bearded Tits need grit at this time of year because they are changing from the soft insect diet of summer to the harder mainly reed seed diet of winter. The grit sits in the gizzard and so grinds up the seeds.
We are also responsible for the colour rings you can see on all but a few birds. The birds are colour ringed as part of a long term (25 years) population and DNA study of this very local species. Remember Leighton Moss is the only place you can regularly see this evocative species in the North West.
The colour rings have also enabled us to study their gritting habits. Every year the adult birds come first to the trays from about mid September to mid October almost all the birds gritting are adults but as the season progresses birds of the year move in. This year to date we have identified 51 different birds using the trays 23 of them adults and 28 this year's young ones. So far this year we have ringed 104 young bearded tits the largest number since 2000 so many more may yet visit the trays.


John Wilson

Blue Tits have a Record Season

Our ringing of blue tits to date suggests that they are on track for an excellent season. Despite a rather low breeding population in our nest boxes following two years of poor productivity the numbers of fledged young was high.

Ringing since then has recorded a high population suggesting good survival . Leighton Moss is typical with 369 caught to date 77 up on the whole of 2008. There is still two and a half months yet to go in which we normally catch many birds. Another pointer to productivity is the percentage of adult birds in the catch. In 2008 it was 21% this year it is only 7% the best since 2006.

Blue tits are normally quite sedentary but in years of high population they often irrupt with birds moving some distance. A pointer that this may happen this year is an adult bird ringed at Heysham on 8/10 and caught six days later at Leighton Moss, a movement of 17 kms in just five days. Not exactly in the same league as our true migrants but still unusual for a blue tit.

At the late September meeting of Lancaster and District BWS most members reported no unusual numbers of Blue Tits at their garden feeders. However all the signs are that there is a large amount of natural food available with a good beech mast and berry crop.

John Wilson

ARE BEARDED TITS PREPARING TO IRRUPT?

Bearded Tits have had their best season at Leighton Moss since the crash in the population in the 2000/2001 winter. To date we have caught 92 free flying juveniles 41 more than last year. Juvenile survival has been very good- of 16 ringed as nestlings no fewer than 13 have been caught as free flying juveniles. This included 5 out of a brood off 6 ringed in a nest box just 4 m. from a Marsh Harrier nest!. There has also been at least one very late brood, just recently we have caught three in juvenile plumage. A male was caught yesterday and it was just starting to moult and still in full juvenile plumage. So must have been hatched in mid to late August.

The first brood younsters are now very active and showing well. We have been recording fat scores and weight of all the birds we have caught. Recently almost all first brood youngsters have some fat in the trachael pit and they have on the average increased their weight by almost 1.5 grams since August.Is this laying down of fat in preparation for a move?

In some years prior to 2000 some bearded tits have irrupted away from Leighton usually in late October and early November We have had sightings from Marton Mere near Blackpool and birds caught in Bolton, Coventry and three in South Yorshire.

If you do see birds away from Leighton please check for rings as all our birds are colour ringed. (A BTO metal ring and three colours). Please note carefully the position of the colour rings and report them on this site. Many thanks.

John Wilson

Reed bed Birds Have a Good Season

Our ringing at Leighton Moss suggests that most reed bed birds have done well this year. Pride of place goes to Bearded Tits with 84 young birds ringed this year the highest total since the crash in the breeding population in 2000 and 23 up on 2008. The first brood has now completed their moult and are showing well with some starting to visit the grit trays. Sightings of colour rings are very welcome please send to johnwilson711@btinternet.com.

Reed Warblers also with 694 ringed are well up on the 553 of last year and a few are still left. Reed Buntings with 59 ringed as similar to 2008. Sedge Warblers at 249 are 21 down on 2008

Of other species Blue Tits seem to have had a successful season with 148 ringed to date compared to 158 in the whole of 2008 and the best part of the season to come. Passage Warblers though are down mainly I think due to the bad weather in August and early September.

John Wilson

Ringing Photos

there are soem really nice photos of ringing, courtesy of the Times. Follow this link to see them:

http://www.timesonline.co.uk/tol/news/photo_galleries/

you need to scroll down the page to the box that says "Bird ringing" and click on "slide show"

enjoy!

paul

Interesting Lesser Black-backed Gulls

There has been a little bit of Mute Swan-like ring-reading 'fatigue' with the Lesser Black-backed Gulls which have been ringed at Tarnbrook, Walney and the Ribble over the last few years.

Please, however, continue to report them e.g. they are developing interesting life histories in relation to winter travels to Iberia and north Africa.

There are also some other very interesting ringed Lesser Black-backed Gulls birds around. Mark Breaks recently unearthed an Icelandic-ringed bird at Stock Reservoir and Steven Grimshaw recently read the following :

Ringed: Orfordness, Suffolk as pullus on 12/7/03
Seen: Laayoune Plage, Western Sahara 19/1/04
Seen: Great Harwood, Blackburn 19/7/09

This is the first Lancashire sighting of any of the 4,000 ringed at Orfordness over the last 13 years. Note that it stayed in Africa during its first winter as is not unexpected, but perhaps not usually this far to the south. Why is this relevant to 'our area'? Note the Blackburn date (and age of the bird) and can we assume it has changed breeding sites to Tarnbrook?

Pete

Reed Warblers Prosper

Large numbers of Reed Warblers are ringed each year at Leighon Moss during our Bearded Tit study. Since 1997 we have registered this ringing in the BTO's RAS scheme which attempts to monitor the survival of adults. With the ringing effort being roughly similar each year we get an idea of population levels as well.

Our average catch of adults in the 12 years from 1997 to 2008 is 176. This year to date we have recorded 166- slightly below average but 13 up on 2008. We may yet catch a few more although most adults appear to leave during the period late July and through August. In the 12 years studied we have only recorded 5 adults in September, although many juveniles are caught in the first half of September.

Reed Warblers appear to be long-lived. This year we have caught one first ringed in 2002, 4 in 2003 and 1 on 2004. This year adults seem to have stopped a little later than usual with 9 adults caught between August 16th and yesterday(25th)- in some years we have not caught any adults at all in this period. Of the 9 adults caught this year 5 were well above the average weight of 11 grams with the heaviest being 14.3 grams. These 5 all showed signs of laying down fat reserves in readiness for migration.

Recoveries from our ringing give some clues as to the timing of this migration. We have had 11 adult Reed Warblers caught on passage along the south coast of England the earliest was on August 2nd and most were during mid August. Tracking the migration further, our earliest date for an adult on migration along the Atlantic coast of France is August 10th.

We also monitor productivity and this year seems to have been well up to average with 430 juveniles ringed to date.

John Wilson