Sunday, 22 June 2014

RAS Ringing at Manor Farm - June 2014

For the second time this weekend I was up at 5 am, this morning though it was for bird ringing rather than twitching. The plan was to visit Manor Farm Country Park in the hope of catching some House Sparrows for my BTO RAS project. I have blogged about the project on previous occasions so won't go through it in detail again. But for those who don't know, the aim is to catch or see as many previously ringed birds between the breeding season (March to September).

Adult Male House Sparrow
To make this easier, all of the birds I catch are ringed with a BTO metal ring on the right tarsus, and a yellow coloured darvic ring, with a single letter and two numbers, on the left tarsus. I started the project in 2000 and have to date ringed over 700 birds,

The Colour Rings used for my RAS Project

It is the peak breeding season for House Sparrows at present, and I had timed this visit in the hope that the first broods had fledged. We set six nets, around the farm buildings in locations that have previously proven to be good capture sites. Our first bird was a Carrion Crow, a species that I had not trapped at the site until last year, and now have ringed four. I think this reflects the number of birds present around the farm, which has increased dramatically in recent years. The next birds were a couple of Dunnocks and then we started catching sparrows. It was now 6:30 and the farm opened to the public at 10, so we had three hours to ring. 

It was a productive session that resulted in a total of 36 birds, of which 27 were House Sparrows. The total was made up of eight re-traps and 19 new birds, of which 15 were juveniles. Both adult and juvenile sparrows have a complete moult post breeding/fledging, therefore usually all wing and tail feathers will be replaced. Typically this will commence later in the season for adult birds, since they can have two or three broods. However, juvenile birds commence moulting in mid June, these will be the first broods.

Juvenile Male House Sparrow - note the white patch behind the eye and
rufous feathers coming through, more rufous feathers were present in the wing.

Of the birds we caught, five were in primary moult. This was generally not very advanced in that only the innermost primary had been replaced and the next was growing; all of the other feathers were old. One individual was in a curious state in that it had replaced all of its primaries, primary coverts and greater coverts, and only some of its tertials and secondaries (see below). It will be interesting to see how this bird progresses its moult, so hopefully I will catch it again over the next couple of weeks.

Wing of Juvenile House Sparrow

During the session we also caught a few other species that are breeders at the site; Wren, Blackbird and a couple of Greenfinches. The female was very tatty, but the adult male was still relatively fresh which was quite surprising for this time of year.

Adult Male Greenfinch

The only other species ringed was a juvenile Robin. I always say to my trainees that when you have a bird of a known age it is worth looking at features, such as tail feather shape and size, shape and colour of tips of greater coverts, so that they are familiar with the features when they catch a contentious bird. There was certainly no doubting this Robins age.

Juvenile Robin

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