NLRG was formed in 1957 to help in the study of birds in the Lancaster and District Birdwatching Society area. There are currently 12 active ringers. Species currently being studied include: Pied Flycatcher, Bearded Tit, Sand Martin, Twite, Goosander, Oystercatcher and Grey Wagtail. Migration has been studied for 28 years at Heysham. We welcome anyone who wants to observe, help or perhaps wish to become a ringer. Photo: A Heysham-ringed Twite on the Mull of Kintyre (thanks to Eddie Maguire)

Sunday 3 November 2013

Bearded Tits October Grit Tray Sightings

This October has turned out to be one of the  most intriguing and at times most frustrating of our nine year study of the gritting behavior of this charismatic species. Despite a good population with 45 young birds ringed this year and at least 26 colour ringed adults identified, sightings on the trays have been the lowest since our study started. The average number of October sightings in past years has been 245, this year we have recorded only 107 despite much effort.

Why the difference? Well  this has been the warmest October since the study started with no frost and an abundance of insects- the main food of Bearded Tits in summer.  So possibly they have not had to turn to what is normally their main food at this time of year- reed seed. this is much harder to digest than insects and they need grit in their gizzard  to grind it up. Interestingly the only days numbers have been present has been on the cooler calm days. One of these fortunately coincided with the filming by the BBC Autumn Watch team when 15 birds were present.

The other difference this year is that the water level is much lower and large areas of dry  substrate, normally under water are accessible to the birds and they could possibly be getting grit there although there appears to be very little grit in the deep peaty soil.

Despite the lower numbers  there were several interesting sightings both of adults which have retained their pair bonds, in one case over three years, and of first year birds which have established pairs  shortly after fledging and are still together.

John

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