[196] Larus fuscus, Lesser Black-backed Gull

[196] Larus fuscus, Lesser Black-backed Gull

Introduction

Larus Fuscus, the Lesser Black-backed Gull, is one of two very common and widespread species of gull that in Britain are now more often seen inland than at sea. The other one was seen yesterday.

Taxonomy

Kingdom – Animals

Phylum – Chordates

Class – Aves (Birds)

Order – Charadriformes (Waders and Gulls etc.)

Suborder – Lari (Gulls etc., Skuas, Auks)

Family – Laridae (Gulls, Terns and others)

Subfamily – Larinae

Genus – Larus

Scientific Name – Larus fuscus

Name

This bird can be compared to the Great Black-backed Gull although its back is not really black. The Latin fuscus means dark or black-brown.

Description

Larus fuscus is very similar to Larus argentatus, almost identical in size, but its back is a darker shade of grey. In some conditions at a distance, it could be called black. Its legs and feet are yellow.

Otherwise, much of what I said yesterday about [195] the Herring Gull also applies to Larus fuscus. The two species are very closely related and the two species of both are sometimes considered as a group of similar species.

The next picture shows both species for comparison.

(The Larus fuscus may be slightly smaller but the apparent difference in size in the picture is mostly due to the perspective of distance.)

In winter they have the same spotted head and necks as Herring Gulls and the young birds are virtually identical. Both species are mottled brown with pinkish legs and black bills. I work on the assumption that juvenile gulls are most likely to be the same species as nearby adults so I won’t guarantee that I have the right species here (or yesterday.)

Habitat

The traditional winter location of Larus fuscus is much wider than Larus argentatus, including Atlantic coasts down to Central Africa, Indian ocean coasts, the coasts of China and parts of North America. It breeds further North around Iceland and the Arctic coasts of Europe.

 In the UK it is found at some seaside locations but is now mainly resident inland, often in towns and cities as an unwelcome visitor.

Other Notes

As noted yesterday, at seaside resorts, Herring Gulls and Lesser Black-backed Gulls tend not to mix. But both species can occur in the same towns and cities inland.

See also

There are a few more very rare occasional visitors in the Gull family but the only other one that is relatively common is Larus marinus, the Great Black-backed Gull. It is a much more of a sea bird and may be spotted with binoculars flying over the sea, or occasionally at rest very near to the sea.

[Note: with two species, one of which has the word ‘Lesser’ in its name, it is tempting to assign the word ‘Greater’ to the other, but ‘Great’ is more usually correct.]

It is noticeably larger than Larus fuscus and a darker shade of grey – almost bleck – but the best distinguishing feature is its pink legs.

It is the largest species of gull and takes four years to reach adult plumage.

[195] Larus argentatus, Herring Gull

[195] Larus argentatus, Herring Gull

Introduction

Larus argentatus, the (European) Herring Gull is one of two very common and widespread species of gull that are now more often seen inland than at sea. The other one will come tomorrow.

Taxonomy

Kingdom – Animals

Phylum – Chordates

Class – Aves (Birds)

Order – Charadriformes (Waders and Gulls etc.)

Suborder – Lari (Gulls etc., Skuas, Auks)

Family – Laridae (Gulls, Terns and others)

Subfamily – Larinae

Genus – Larus

Scientific Name – Larus argentatus

Name

Gull comes from Welsh and Cornish roots replacing the earlier name ‘mew’ for the birds. Both are ultimately onomatopoeic.

The Herring Gull is, of course, named for its association with fish called herrings. You may think you know what a herring is but common names are never simple. The three species of Clupea are called herrings, but then so are about twenty related species in the family Clupeidae and about a dozen less closely related species! [We won’t meet them in this blog.]

The Latin larus from Ancient Greek laros referred to a gull or other large seabird.

Argentatus means silver (coloured). There is another bird native to Australia called the Silver Gull, Chroicocephalus novaehollandiae. (New Holland is Modern Latin for Australia!)

Description

Almost all gulls used to be included in the genus Larus but since about 2005 smaller species have been split off into [080] Chroicocephalus and other genera.

All the large gulls in the genus Larus are very similar. They are medium to large birds. mostly grey or white with some black markings. They have stout, mostly yellow bills and pinkish or yellowish legs and webbed feet.

Larus argentatus used to include the following, which are now generally considered to be separate species.

The European Herring Gull is white with a light grey back and black tail. Its bill is chunky with a pointed down-turned upper beak, yellow with a red spot. Legs and feet are pink. The iris of the eye is yellow. Male and female birds are identical is all stages of development although the adult male is slightly larger than the female. It is found around the coasts of northwest Europe from Northern Portugal to Norway including the British Isles and Iceland.

Gulls used to be mainly sea birds but, in the UK the Clean Air Acts changed things from about 1960. In an attempt to reduce the frequent occurrence of smog, the direct burning of coal was discouraged in favour of more smokeless fuels. Rubbish used to be routinely incinerated but now it mostly goes to landfill sites, where vast quantities of food waste are available to scavenging birds such as gulls. There are also many office buildings with flat-topped rooves where gulls can breed.

In the UK Herring Gulls are now much more common as inland birds where they feed almost entirely from rubbish dumps. This continues with modern household recycling schemes because much office and industrial waste is not sorted so rigorously. Councils try to discourage the birds and often this is done by falconry – a raptor at a rubbish dump keeps the gulls away. But the birds have learned that the falconer only works on a forty-hour week and they come as soon as the keeper with his discouraging falcon goes home.

Juveniles and Winter

Identifying nearly identical species of gulls is not made easier by variations in plumage.

The winter (non-breeding) plumage is similar with grey-brown streaky spots on their head and necks.

With the juveniles it gets more complicated. Smaller gulls like [080] the Black-headed Gull, mature in just over a year but larger gulls take longer. Larus argentatus in its first year is speckled all over in dark brown and white and its bill is completely black. It has first winter, second winter and third winter variations as it gradually changes to look like its parents, with the bill staying black for most of this period.

Habitat

The traditional location of Larus argentatus is the coastal area of Northwest Europe from Northern Spain to Finland, mostly as a resident species. In the UK it is now mainly resident inland. often in towns and cities as an unwelcome visitor.

Other Notes

When I see large gulls at seaside resorts, they are generally either Herring Gulls or [196] Lesser Black-backed Gulls. The two species tend not to mix. But both species can occur in the same towns and cities.

See also

The Yellow-legged Gull, Larus michahelis, is found more over continental Europe but the occasional stray is sighted in Britain. It is similar to Larus argentatus but has yellow legs.

If you spot a gull looking like a Herring Gull but with yellow legs in England, it could be Larus michahellis or it could be an unusual rare variant of Larus argentatus. The most likely option is a hybrid cross between Larus argentatus and [196] Larus fuscus, coming tomorrow.

The Common Gull or Mew Gull, Larus canus, is a relatively uncommon gull found over much of northern Eurasia and north-western North America. Its name may be derived from its liking for common land as a winter habitat. They are smaller than the Herring Gull and are described as having greenish-yellow legs and bill but, to me, they are yellow – without the red spot.

See tomorrow for more Larus species.