The Wren (Gærdesmutte) is a common garden bird in Denmark, small but with an amazing song! Photo: Jennifer Lynch
This week at the university I set up some mist nets, which are specially designed to catch small birds for ringing or banding. By catching the birds, and giving them individual lightweight metal rings, this allows us to recognize the birds again in the future and follow their progress. I was also hoping to catch some of the 500 chicks (Blue tit & Great tit) which were ringed last year while they were still in the nest boxes.
A male Blackbird (Solsort), the most common breeding bird in Denmark. Photo: Jennifer Lynch
When a bird has been caught, a number of measurements can be made, including weight and wing length which can give us an indication about the health or fitness of the bird. All this information can be pieced together to give a picture of the health of the population and help identify any changes over time.
Redstart (Rødstjert) breed in Denmark and other northern countries in the summer and migrate to Africa to overwinter. (This is a male) Photo: Jennifer Lynch
Over two mornings at SDU I managed to catch a total of 23 birds, with 12 different species. These included both resident birds like Robin (Rødhals), Wren (Gærdesmutte) and Greater Spotted Woodpecker (Stor flagspætte) and some birds that migrate from Africa to breed in Denmark in the summer like Redstart (Rødstjert), Blackcap (Munk) and Chiffchaff (Gransanger).
Female Greater Spotted Woodpecker (Stor Flagspætte). Photo: Rasmus Sloth Pedersen
Among them were 2 Great tits (Musvit) and 2 Blue tits (Blåmejse). The females were clearly breeding, as they had developed a large “brood patch”. This is a naked, featherless patch on the belly, which allows the birds to transfer as much heat as possible to the eggs during incubation.
By blowing on the feathers on the stomach you can reveal the females brood patch, which allows her to transfer her body heat to the eggs she is incubating. Photo: Jennifer Lynch
Among the 23 birds I caught, I did manage to catch one bird with a ring already on it’s leg. It was a Great tit with ring 9Z15066. After the ringing session I checked my records from last year and I could see that this birds was ringed as a chick in box 57 in the north west part of the woods (Area 6), one of the closest boxes to Bilka!
A female Mallard (Gråand) was a nice surprise in the net. Photo: Jennifer Lynch
One bird I didn’t really expect to catch was this female Mallard, who I found walking around in the bottom of the net. The nets I used are specifically designed to catch small birds, but can in some cases catch larger birds too! She also received a ring, and was released to join her mate, who wasn’t far away. I will be carrying out more ringing around the campus during the summer months, so if you would like to come along and see how it works, keep an eye on our Facebook page.