nominate Lesser Black-backed Gull (L. f. fuscus)

(last update: 26-11-2014 )

adult fuscus: March

Gulls at Ashdod Israel, 16 March 2010.

In northern Europe, several ringing programmes were started to get more information about the feeding aspects, migration and behaviour of Larus fuscus fuscus. One of such ringing programmes is executed in the three northern counties of Norway: Nordland, Troms and Finnmark.
Morten Helberg, Geir Systad, Ingve Birkeland, Nils Lorentzen & Jan Bustnes published an article about this research in Ardea 97, 2009, titled: Migration patterns of adult and juvenile Lesser Black-backed Gulls Larus fuscus from northern Norway. The complete PDF can be found HERE. The summary for juveniles can be found in the fuscus 1cy October section, the summary for adults can be found in the fuscus adult October section.

Nordland - Hortavær

Hortavær, in the very south of the county Nordland, had a homogenous population of about 400 pairs of fuscus type birds in 2005 (birds showing blackish upperparts). In this population, only one or two paler birds have been observed; one of these paler birds may possibly have raised chicks in a mixed pair with fuscus. In 2008 a new population of 200 pairs was discovered nearby Hortavær; and also on this location was one pale non-breeding bird.

Between 2005-2007, 509 birds have been ringed, and 26 birds were rediscovered. Despite being a colony of pure fuscus birds, several individuals were found following the western migration route, through the North Sea, south along the Atlantic coast of the Iberian peninsula and north Africa. Here are two example males from this population: J309 and J130. J309 (thumbnail left, click to enlarge), is a perfect illustration of jet-black adult nominate fuscus, breeding on Hortavær, Nordland. This Archipelago contains a pure population of such dark fuscus birds. Complete moult still not started by mid-July. J130 (thumbnail right), illustrates type of breeding habitat for this colony.

And also two example females from this population: J303 (left) and J127 (right). Again these birds illustrate nicely the darkness of the upperparts, leaving almost no contrast between the tone of the wing-coverts and the medial black bands on the primaries. By clicking the thumbnail of J127, you also find a map with migration strategy followed by this bird, which was seen in western Europe and Morocco. More details about the upperpart grey tone for various Lesser Black-backed Gull colonies throughout Europe, you can look at the fuscus adult August section. Here, you will see the findings of E Barth, Norwegian scientist who plotted grey tones in the 1960-1970's. Much of what he wrote, still is true in Norway.

In fuscus colonies, like in other white-headed gull species, you can find 3cy birds which return to inspect their future breeding grounds and feeding grounds, and some may even try to participate in courtship. In Hortavær, several 3cy birds, ringed in 2005 and 2006 have been seen back in the colony. These thumbnails give some illustrations. Probably, most of such 3cy birds involve males. Above left bird is J304, caught on the nest as 3cy fuscus. The right thumbnail shows 3cy J054, ringed as pullus in 2005 and returning in the colony in 2007. Below left is 3cy J229 and below right is 3cy J214, of which is included a map with migration strategy followed by this bird (seen in N Germany and Belgium).
Harry Vercruijsse (1999), who did research in the Netherlands on Herring Gulls in the dunes, found the breeding attempts by such young birds not really successful in their first year back in the colony. Birds in 3cy may occupy a territory, but real breeding attempts often start the next year. Still, it may be a good strategy to return at such early age, to have advantage over other males regarding best breeding locations and feeding grounds. Similar results were found by Chabrzyk & Coulson (1976) on the Isle of May, SE Scotland.
[HJP Vercruijsse, Zilvermeeuwen uit de duinen van Schouwen, 1999. Publication ibn dlo, Tilburg, ISBN 9090131671.
G Chabrzyk & JC Coulson, Survival and recruitment in the Herring Gull Larus argentatus, 1976. J of An Eco 45: 187-203.] (thumbnail left: 3cy J243).

Pale-mantled adults in Hortavær, Nordland. This Archipelago contains a pure population of dark fuscus birds, but sometimes a pale-mantled bird is seen here as well. Maybe there has been one breeding attempt of mixed fuscus type x pale-mantled bird.

Troms & Finnmark

North of the county Nordland lies Troms and the northernmost county is Finnmark. Starting in the south, Svartskjeran near Ibestad is the first colonies that was visited to measure and colour-ring Lesser Black-backed Gulls. Table 2 gives the breeding population for the counties Troms and Finnmark.

Click on Troms-Finnmark map below for larger image.

Troms - Svartskjeran / Ibestad

This small colony with maximum 10 breeding pairs consists of pure fuscus birds. All colonies north of Svartskjeran hold mixed populations with both fuscus type birds and pale-mantled birds. The island Svartskjeran was visited from 2005-2008 and 28 birds have been ringed here. The thumbnails of J000, J0R1 and J0R2 represent the type of birds breeding here, with jet-black upperparts. One of these example birds is J0R1, a bird ringed on the nest in 2005. This individual has been recorded several times in February and March 2008 at Ashdod, Israel. J0R1 follows the eastern migration route, earlier described by Kilpi and Saurola in 1984 for nominate fuscus.
Single observations of colour ringed birds from N Norway, e.g. observations from central inland Norway, the Baltic Sea and Israel demonstrate the eastern migration route (eastern flyway through Finland, Black Sea, Israel to the Rift Valley into the African Great Lakes). However, there were also observations of Norwegian birds from 'pure fuscus colonies' in England, which later that winter turned up in Morocco and another 'pure fuscus' bird in Portugal.

Troms - Lemmingsvær

Lemmingsvær holds one of the larger colonies in northern Norway, and ringing started already in 2002, with now 226 birds ringed in the period 2002-2008. Maximum breeding pairs is 45 birds for this location, with about 50% of these breeders being pale-mantled birds (origin either from graellsii populations from the west or intermedius birds colonising from southern Norway).
Example birds are JM82, JM85 (female) and JM88 (male). JM82 was not sexed. The complete moult has still not started by mid-June in this bird. It is obviously a pale-mantled bird, with a migration strategy much in line with what can be expected for intermedius birds from southern Norway or graellsii birds from the U.K. You can view the map by clicking the thumbnail of JM82.

Troms - Froholman / Eldhusholmen

The ringing programme at Froholman started in 2005 and within three years (2005-2007) 8 adults were caught on the nest. The catches of juveniles were better, with 162 juveniles colour ringed in the period 2005-2008; although last year only 2 birds were caught. 2008 has been a dramatic year regarding juveniles in all north Norwegian populations. None of the adults have been rediscovered outside the breeding range, up to May 2008, but three juveniles were seen again.

One of these birds is shown here as well, J916. This bird was seen in Israel and one year later in Egypt, nicely demonstrating the migration route already known for nominate fuscus from Finland. When J916 turned up in Egypt in February 2008 as 3cy bird, the upper-part grey tone was very dark, supporting the idea this is an offspring of pure fuscus.

As the first thumbnail shows, the population on Froholman obviously holds both pale-mantled birds and very dark fuscus-type birds.

Troms - Nordfugløy

The most northern island in the county Troms is Nordfugløy. Here you find a Lesser Black-backed Gull colony in cloudberry mires, about 300 meters above sea level. The oldest data about the presence of this colony are from 1963 when 125 pairs were estimated. Still, there was nothing known concerning the subspecies composition before the first adult birds were caught and colour-ringed in 2002. The breeding population varies a lot in numbers between the years, with a minimum of 15-20 pairs in 2002, and with a maximum of 100 pairs in 2006 and 2007. Nowadays, with about 100 pairs, it is the largest colony of Lesser Black-backed Gulls in northern Norway.

The island also hosts a breeding population of 100+ pairs of arctic skuas and 200+ pairs of Common Gulls. There is only one island in this ringing program which is higher up north: Loppa Island, which is a similar colony at about 200 meters above sea level.

The ringing program on Nordfugløy started in 2000, when juveniles were ringed. From 2000 to 2008, 172 juveniles were ringed here. Up to May 2008, 20 of these juveniles were seen outside the breeding range. Between 2002 and 2007, 17 adults were ringed as well, with 7 rediscoveries. This is a remarkable high recovery rate, certainly due to the predominant western migration route chosen by the adults breeding on this island. Pale-mantled birds from Nordfugløy have been rediscovered in Portugal, Spain, Italy and Libya. One dark fuscus-type bird has been observed frequently in Israel, J0X0 (see thumbnail right above).

adult March - description

By March many birds migrate north from nthe winter areas in Africa and pass Israel, where all images have been taken on this webpage. March is by far the best month to score ringed fuscus in Israel. In the January section and in the February section you can see that in ringed adult fuscus (provenance on age and location), the last phase of the complete moult includes growing P10. March and April are months used for migration and since fuscus is a long distance migrant one may expect no moult in this period. This appears to be true regarding the flight feathers. The list shows the primary moult scores for ringed birds and unringed birds of which the full set of primaries is visible in images.

"Primary moult scores for ringed and unringed fuscus in March"

P10 fully grown; P1-P10 present. PMS=0.
white ring: C1N9, C3Y1, C5P4, C5P8, C9XX, CCJ9, CE41;
red ring: C7EP, CE43, A170;
blue ring: J0X0;
black ring: J449;
ringed birds: 12.
unringed birds: 17.

It is difficult to determine exact moult stages in the wing-coverts in birds that are as dark as adult fuscus. For March, with the complete moult just finished, it may sound logic not to expect to much moult in the wing-coverts. And this is true for Finnish fuscus as far as we have checked the birds on this site. But interestingly, two birds, both from far northern Norway showed wing-covert moult: J0X0 and J20E.

March 13 2014. "the gathering".

Last days of March or sometimes the first week of April: Larus fuscus circling in groups to migrate north to the breeding grounds.

Spring Baltic Gulls in Israel. Picture: Amir Ben Dov.

Larus fuscus fuscus, March 21 2009, Yavne 4 water storage ponds, Ashdod, Israel. Picture: Amir Ben Dov.

Larus fuscus fuscus, March 21 2009, Yavne 4 water storage ponds, Ashdod, Israel. Picture: Amir Ben Dov.

Larus fuscus fuscus, March 21 2009, garbage transfer point area in Ashdod, Israel. Picture: Amir Ben Dov.