L is for Larus

LARUS (Lariid gulls)

Ok, this is cheating. This entry could have been focussed on the Lesser Black Backed Gull Larus fuscus, but it is difficult to talk about this species without comparison to others in the genus*.  

Any trip to the British coast will have a background of ‘gull-ness’, both the soundtrack of their territorial ‘trumpet calls’ and the image of pale ‘V’-shaped birds flying across the blue sea (No ship painting is worth its salt without gulls in), and of course the presence waiting for you to drop a chip. Love them or loathe them, they are the classic sea bird (Indeed the name Larus means ‘a sea bird’) and they add a certain romance to a beach holiday.

But look closer and you’ll notice different species. The larger gulls are distinguishable by the shade of their wings. The classic blue-grey ‘Sea gull’^ᵻ the Herring Gull L. argentatus (meaning ‘decorated with silver’), the darker grey Lesser Black-backed Gull L. fuscus (meany ‘dusky’) and the pitch black, Greater Black-backed Gull L. marinus, the largest gull in the world.  They are fairly similar, with a dagger-like yellow bill, red spot on the lower jaw (which acts as a feeding signal to their young), black-and-white tipped wings and a furrowed brow. The juveniles are a spotty brown. You may see another Lariid, the Common gull L. canus which is smaller with a slimmer, all yellow bill and rounded head. They are named from the middle English meaning plain, not abundant². A recent arrival, The Mediterranean gull L. melanocephalus , has a black head in summer, reduced to a spot in winter and a thick red beak (not to be confused with the black-headed gull Choriocephalus ridibundus).

Of course, you don’t have to go to the coast any more to see gulls in Britain. They’re now common in our cities, parks and rubbish dumps.  Herring gulls only moved into cities during the 1940’s³. Since then both Herring and Lesser Black Backs have increasingly exploited the artificial cliffs of flat-roof buildings for nesting (Much to the dismay of many human occupants), whilst commons forage on playing fields. The Great black-back is more coastal and hasn’t taken to landlubbing ways.

Gulls are able to adapt to new lifestyles with their generalist diet. They are omnivores, gulping down a variety of land and water invertebrates, small vertebrates, some plantstuffs, carrion and human scraps . On the coast they are mainly fish eaters, hence the herring gull was named as feeding flocks signalled the location of herring Clupea spp. shoals to fisherman, whilst the lesser black back was known as the ‘Coddy moddy’ for following young cod Gadus morhua².  Gulls can swallow large fish whole to gorge themselves (I once saw Japanese tourists feed a whole medium battered cod to a herring gull in one!).
The Great black back is a ferocious predator of larger animals including rabbits and seabirds. The common gull takes smaller fish and invertebrates, and unusually eats grain, hence the Devonshire name ‘Barley bird’².
Gulls have developed new behaviours to get their food, such as pirating from other seabirds, pattering the ground with their feet to bring up earthworms, dropping shellfish onto rocks to crack them and puncturing bin bags. They find a bonanza of easy pickings at rubbish dumps, but their adventurous tastes get them into trouble with inedible objects. One gull was found to have swallowed a mobile phone⁴!  The increasing amounts of plastic waste in our oceans is a huge problem for many seabirds.

With gulls increasingly moving into our living space, they seem to be doing well. The Lesser Black Back, traditionally a summer migrant wintering in Southern Europe, is even increasingly staying over⁵. However, the bigger picture is not good. The Herring gull is on the red list of threatened British birds, and the Black-backs and Common are classed as Amber^3,6. Rather than expanding, gulls are being pushed to move inland as overfishing depletes their natural food sources⁷. Whilst landfills once attracted them in needy times, inland gulls are now doing better than coastal dwellers, even though we try to deter them as a nuisance⁷. The fact is, if we want our seaside soundtrack to last, Britain’s gulls need all the support they can get.

*All of Britain’s gulls except the Kittiwake Rissa tridactyla used to be classed in the Larus genus, but a genetic study revealed this to be inaccurate¹. Thus the Black-headed Gull Choriocephalus ridibundus and the Little Gull Hydrocoloeus minutes are now classed separately.

^ᵻThe term 'Seagull' is technically wrong. It is not opposed to anything (i.e. there are no land gulls, river gulls etc) and most gulls do not rely on the sea. It’s often said only to truly apply to the kittiwake, a strictly oceanic species, but the name originally applied to the Common gull².

References

11-      J.-M. Ponsa, A. Hassanina, and P.-A. Crochet. (2005) Phylogenetic relationships within the Laridae (Charadriiformes: Aves) inferred from mitochondrial markers. Available from: http://www.researchgate.net/publication/7692222_Phylogenetic_relationships_within_the_Laridae_%28Charadriiformes_Aves%29_inferred_from_mitochondrial_markers

22-      Fransesca Greenoak. (1979) All the Birds of the Air. A. Brown and Sons.

33-      RSPB. (2013) Advice: Urban Gulls. Available from: http://www.rspb.org.uk/advice/gardening/unwantedvisitors/gulls/urbangulls.aspx

44-     C.J.Camphuysen, S.Boekhout, A.Gronert, V.Hunt , T van Nus. and J. Ouwehand, (2008). Bizarre prey items: odd food choices in herring gulls and lesser black-backed gulls at Texel.  Sula 21, 49-61. Cited by: Darren Naish. (2009) Mobile phones, medals, a doll’s legs, an entire army… is there anything a gull won’t swallow? Available from: http://scienceblogs.com/tetrapodzoology/2009/12/19/gull-swallows-phone/

55-      R.A. Robinson./ (2005) BTO BirdFacts: profiles of birds occurring in Britain & Ireland: Gulls: Lesser Black-backed Gull Larus fuscus   [Linnaeus, 1758]. Available from: http://blx1.bto.org/birdfacts/results/bob5910.htm

66-      R.A. Robinson. (2005) BTO BirdFacts: profiles of birds occurring in Britain & Ireland. (BTO Research Report 407). BTO, Thetford. Available from: http://www.bto.org/birdfacts

77-BBC. (2012) Who What Why: Why are there so many seagulls in cities? BBC News Magazine. Available from: http://www.bbc.co.uk/news/magazine-19490866