Jan 18, 2012

The white winged invasion continues

The first two weeks of the new year here in Bergen have given us the greatest influx of White-winged gulls ever recorded. At this writing, 18 Iceland Gulls (Larus glaucoides) and 4 Glaucous Gulls (Larus hyperboreus) have been seen in the county of Hordaland in 2012. Further north in Norway the numbers are higher with over 24 Iceland Gulls in Uthaug harbour outside Trondheim on the 15th of January and 25 individuals on Smøla (a bit south of Trondheim) on the 16th of January. Of the 18 Iceland Gulls observed in our county, 8 are adults, 1 third winter, 5 second winter and only 4 first winter. In previous years, the first winter birds were clearly dominating. When the adult Iceland Gull was seen at the island of Fedje on January 8th, it was over ten years since the previous record. Strangely enough, this was at the exact same location at Mulevågen, Fedje.

Since the last blog post, two more white-winged beauties have been ringed in Bergen. First a second winter Iceland Gull was ringed in the city centre lake on the 12th of January. After a failed attempt on our lunch break, we managed to catch it on the second trial after work. This second winter is the first second-winter bird to be ringed in Norway and the 12th Iceland Gull in total to be ringed in Norway.

J8Y7 the 12th Iceland Gull to be ringed in Norway

On the 16th of January, the most eager twitcher in Bergen called and said that there were two Glaucous Gulls in the city centre park. In addition to JP370, which had been in park every day since ringing on the 3rd of January, a second winter Glaucous Gull was present. This new one was an easy catch and I think we only used minutes before we had it and could measure, ring and take blood samples. Measurements suggests that this new one is a female.

JP363 a nice second winter Glaucous Gull

JP370 is still present in the park, terrorising the Herring Gulls.

The adult Iceland Gull from the island of Fedje 8th of January. The first adult in over ten years in our county.

Ringing summary for December 2011

In December we ringed a total of 33 gulls. Most Herrings but two new Black-headed Gulls was nice bringing the year total up to 11.

Species1YSub adultAdult
Mew Gull238
Herring gull936
Black-headed Gull002

Jan 3, 2012

More white winged beauties

Photo: Frode Falkenberg
In the lunch beak today we decided to have a look for the old faithful Ring-billed Gull (Larus delawarensis) and read some Mew Gulls. It did not take long time before we spotted it on exactly the same pier as when it was found for the first time this winter. Today we tried to feed out bread to see if it was hungry. 'All' the other gulls on the pier flown against us and took bread but the Ring-billed remained and eventually decided to fly in the opposite direction. Bread do not seem to tempt this bird, maybe warm fish cakes or salmon will... When we headed back to work we agreed that a quick check in the city centre lake is a must. When driving the few hundred meters towards it we both get a text message from Frode Falkenberg, who had spent his lunch gulling in city centre lake, saying "2Y Glaucous Gull which feed on bread in the city centre lake now".

We had all the equipment in the car and went for a new white gull challenge. Within 15 minutes we had it and could put a ring the county of Hordalands second Glaucous Gull (Larus hyperboreus). This one was really big with a head and bill measurement of 152,4 mm and therefore surly a male. The one we caught 13th of October was considerable smaller for a male and had just 144,4 mm in the same measurement.

Frode Falkenberg had used some time getting pictures of this white giant and the nice picture of it before ringing in this post is his.

Jan 1, 2012

White winged New Year's Day

Happy new year to all! The new year started really good for Urban Ringing, Bergen with our second ringed Iceland Gull (Larus glaucoides). The bird was discovered by Frode Falkenberg on 30th of December at Osøyro 30 kilometres south of Bergen. There was two first winter Iceland Gulls at the site but only one of them was feeding on bread. On New Year's Eve we decided to make one of these Iceland Gulls our first ringed bird in 2012. A success would also make us the winner of the Iceland Gull bet we made the 27th of November. When we woke up the weather was really bad with heavy rain and we feared that the the catching would rain off. However in the afternoon we headed of to Osøyro when the rain seemed to stop for a moment. When we arrived we found the bird immediately and after one failed try we caught it.

Compared to the one we caught 27th of November this one was in better condition. It's body mass was 675 g and when handling the bird it felt like it had more fat because the breast bone was not particular sharp. In comparison the gull from the 27th had a body mass of only 520 g which is below the rage given in literature. Glutz von Blotzheim and Bauer (1982) give the range 620 to 735 g for first winter females. The sex is unknown for both individuals, but analysis of the blood samples will later give us an answer.

Iceland Gull J8Y5 performing long call minutes
before catching.
Wing of Iceland Gull J8Y5.

When Frode found the bird the 30th of December he noted some black spots above the eye and assumed this to be parasites. When the bird was ringed we could have a closer look and soon became quite sure that the spots was bird louse or Mallophaga. We sampled some and will take them under the stereo microscope and try to determine the species. It is interesting to see that the Ross' Gull (Rhodostethia rosea) in south western Sweden also have similar dark spots on exactly the same position above and behind the eye. When birds are infested with ecto parasites like Mallophaga they tend to be more visible in the head because this is one of the most difficult body parts to preen.

Head of Iceland Gull J8Y5. Note the black spots behind the eye. This is probably Mallophaga or bird louse which is parasites of birds.

We also found a new Iceland Gull. This second winter suddenly showed up when feeding out bread. This is the third Iceland Gull at this location in three days. We did not see the second first winter bird today.

2012 started perfect and 2011 ended with 72 gull readings on the 31st of December (most Herring and Mew Gulls) which is a new all time high for Bergen. A small ice cap on the lakes and sunny weather are the two most important reasons for this. The 31st was also the first day without rain since 7th of December and the rain have really been pouring down on the majority of these days.