Aug 4, 2011

The natural born sparrow killer, J8Y3

Lesser Black-backed gull J8Y3 born on a roof in the middle of University of Bergen campus
When reading literature the main food source of Lesser Black-backed gulls (Larus fuscus) are fish. A study by Bustnes et. al (2010) found that saithe (Pollachius virens) and herring are the most important food sources of chicks. However gulls are regarded as generalists and will take advantage of every kind of food that are available. This is probably an important factor for their success as urban breeders.

This individual (J8Y3) was born at the roof of VilVite centre at Marineholmen in the middle of Bergen city centre. When it was close to fledge it jumped off the roof when some workers did some maintenance on the roof. Down on the ground it was an easy target for us and we ringed it the 14th of July but gave it poor hope for survival as it did not seemed frighted at all.

Four days later we found it some hundred meters away in the park. When we feed the other gulls with bread it it took some pieces but then suddenly it grabbed a young House sparrow (Passer domesticus) held it in the beak until it was dead and swallowed it in one go. We believed this to be of pure luck mostly since this is a young and inexperienced individual.

Some days later we experienced exactly the same. When we feed breed in order to read a metal ring on a Black-headed gull we heard the death screams from House sparrow and then saw the Lesser Black-backed young standing with it in it's beak. It took under a minute before the pour sparrow was dead and it could be swallowed in one go. This time we quickly got our camera equipment form our bags and took some shots and video.

This prove the ability of these beautiful gulls to be generalists and take advantage of every food source available. This bird which we first thought had small chances for survival will hopefully be reported from Anza, Agadir in Morocco in one of the following winters.

1 comment:

  1. I'd like to report a sighting today of J8Y3 from Sheffield, Yorkshire, England. Several hundred LBBG's are currently feeding on the city rubbish dump, and were today cooling off in the river, allowing the ring to be read (and photographed).
    Interestingly another Norwegian rung LBBG (JNA5) was present in the same area on Tuesday.

    Andy Deighton (