Mar 22, 2010

Greylag goose ringing update

The other day I received an update from Alan Leitch of the Orkney ringing group about the Greylag goose ringing that I had been along to giving a hand out in the summer time. On the 8th of July 09 at the loch of Hundland on the north west of the mainland the ringing group went to work on the moulting flightless flock there. The evening was chosen to try and reduce the effect of the predatory Bonxies that were a present and constant danger to the flightless flock and their youngsters.

On that evening we had captured the birds by means of driving the flightless breeding/moulting flock in to a prepared corral. We succeeded in corralling 191 birds which was about thirty percent of the birds present at the site. Preceding counts on the loch had established that there were at a peak 640 birds on June 30th when 82 broods and a total of 307 goslings giving 3.74 as an average brood were noted. This compares to 08 when a count of 500 birds with 58 broods and 215 goslings giving 3.70 as an average brood size. 25 marked birds from the 08 count were recorded on Hundland loch during this breeding season, many with goslings in tow.

Since July 08 all the sightings of the collared birds have been entered into a data base with some surprising results. about 90 % of the collared birds have been reported within 5km of Hundland loch with the furthest local birds appearing on Shapinsay just 20km away. The only exception to this local pattern have been sightings of birds on the Buckenham Marshes down in Norfolk!

In 08 two of our collared goslings made the 790 km trip to East Anglia. DIS and DIU had somehow managed to head off in an unexpected direction, possibly in the company of other geese This pair managed to return to Orkney to be recorded at RSPB Durkadale close to the ringing site. DIS remained at Durkadale and DIU headed off to Milldam on Shapinsay. Neither bird was seen again until they showed up yet again on Buckenham marshes on the 3rd of Jan!. This time they had a couple of the 09 first year birds in tow HAK and HAJ neither of these had been reported since ringing in july. They have been spending most of their time on the river Yare between Buckenham and Claxton marshes Norfolk since January. The interesting thing here is that these birds are to young to be related. DIS and DIU did not breed in 09 as they were to young. All four birds have been spending time with ‘feral’ Greylag and Canada geese although often reported as only loosely associating with other geese outwith the main group of ten birds. It does make you wonder if all the birds are Orcadian though! Interestingly though another gosling was reported shot to the BTO. This one HFS was shot at Wickhampton Acle Norfolkthis is in the close locality to the Orkney birds and begs the question was it one of the migrating group? But as Allan says we will never really know. Hopefully we will see all of these birds return to The west mainland possibly even on Durkadale come April. The oldest of them will be ready for breeding this year so the story will hopefully continue.

On a darker note the breeding population continues to expand and the pressure to reduce numbers dramatically looks like it is going to happen sooner or later. Different geese scaring methods to keep them from grazing new growing crops are being researched but I think little success is being achieved so they and their youngsters to come may have to take their chances in the future.

In December 09 the Grey goose count for the whole of Orkney revealed a staggering count of 80,538 of which an estimated 10-12000 (11%) currently summer on the islands. It is likely that this amount of birds is affecting other traditional breeders but I don’t think that any real research yet exists to support the idea. Some form of control looks like it will eventually come about though.

Finally there was the leucistic white Greylag known as Blondie or more properly HBF. You may have seen this bird in the photos I posted last July. It was amazing that it had survived the predation from Bonxies and made it to a first year bird. Its more amazing still that it has survived the trophy instincts of local and commercial shooters. Blondie is doing well, alive and kicking and still out west.

My thanks to Alan and the Orkney ringing group for the update and the opportunity to get out and help in the first place.

If anyone has sighting of any of these collared birds anywhere and at any time could you please report them to…


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