Black-headed gull

The black-headed gull (Chroicocephalus ridibundus) is a small gull that breeds in much of the Palearctic including Europe and also in coastal eastern Canada. Most of the population is migratory and winters further south, but some birds reside in the milder westernmost areas of Europe. Small numbers also occur in northeastern North America, where it was formerly known as the common black-headed gull. As is the case with many gulls, it was previously placed in the genus Larus.

Black-headed gull
Adult summer plumage
Adult winter plumage Colony sounds, Suffolk, England
Conservation status
Least Concern (IUCN 3.1)^[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Laridae
Genus:	Chroicocephalus
Species:	C. ridibundus
Binomial name
Chroicocephalus ridibundus (Linnaeus, 1766)
Map of eBird reports of C. ridibundus   Year-Round Range   Summer Range   Winter Range
Synonyms
Larus ridibundus Linnaeus, 1766

The genus name Chroicocephalus is from Ancient Greek khroizo, "to colour", and kephale, "head". The specific ridibundus is Latin for "laughing", from ridere "to laugh".^[2]

The black-headed gull displays a variety of compelling behaviours and adaptations. Some of these include removing eggshells from one's nest after hatching, begging co-ordination between siblings, differences between sexes, conspecific brood parasitism, and extra-pair paternity. They are an overwintering species, found in a variety of different habitats.^[3]

Description

This gull is 37–44 cm (14+1⁄2–17+1⁄2 in) long with a 94–110 cm (37–43+1⁄2 in) wingspan and weighs 190–400 g (6+3⁄4–14+1⁄8 oz).

In flight, the white leading edge to the wing is a good field mark. The summer adult has a chocolate-brown head (not black, although does look black from a distance), pale grey body, black tips to the primary wing feathers, and red bill and legs. The hood is lost in winter, leaving just two dark spots. Immature birds have a mottled pattern of brown spots over most of the body,^[4] and a black band on the tail. There is no difference in plumage between the sexes.^[5]

It breeds in colonies in large reed beds or marshes, or on islands in lakes, nesting on the ground.^[5] Like most gulls, it is highly gregarious in winter, both when feeding or in evening roosts. It is not a pelagic species and is rarely seen at sea far from coasts.

The black-headed gull is a bold and opportunistic feeder. It eats insects, fish, seeds, worms, scraps, and carrion in towns, or invertebrates in ploughed fields with equal relish.^[5] It is a noisy species, especially in colonies, with a familiar "kree-ar" call. Its scientific name means laughing gull.

This species takes two years to reach maturity. First-year birds have a black terminal tail band, more dark areas in the wings, and, in summer, a less fully developed dark hood. Like most gulls, black-headed gulls are long-lived birds, with a maximum age of at least 32.9 years recorded in the wild, in addition to an anecdote now believed of dubious authenticity regarding a 63-year-old bird.^[6]

Distribution

Black-headed gulls can be found over much of Europe. It is also found in across the Palearctic to Japan and east China.^[7] Small numbers also breed in northeastern Canada and can be seen in winter in northeast North America as far south as Virginia, often with the similar-looking Bonaparte's Gull and also in some Caribbean islands.

Behaviour

Eggshell removal

Eggshell removal is a behaviour seen in birds once the chicks have hatched, observed mostly to reduce risk of predation.^[8] Removing the eggshell acts as a way of camouflage to avoid predators seeing the nest.^[9] The further away egg shells are from the nest, the lower the predation risk.^[8] Black-headed gull eggs experience predation from different species of birds, foxes, stoats, and even other black-headed gulls. Although mothers show some form of aggressiveness when a predator is near, in the first 30 minutes, wet chicks can be easily taken by other black-headed gulls after hatching when the parents of the wet chick are distracted.^[9]

Black headed gulls also carry away other objects that do not belong in the nest. The removal of eggshells and other objects is important not only in the incubation period but also during the first few days after the eggs hatch. However, the removal process seems to increase as time goes on.^[10] The removal is done by both the male and female parents, normally lasts a few seconds and is done three times a year.^[9]

A black-headed gull is able to differentiate an egg shell from an egg by acknowledging its thin, serrated, white, edge. Therefore, the weight of the egg or eggshell does not play a role when determining its value.^[11]

Earlier eggshell removal hypotheses

Other hypotheses have attempted to explain the survival value of black-headed gulls removing their eggshells from the nest, including:^[9]

1. The sharp edges of the shells after hatching could harm the chicks^[9]
2. The eggshell could somehow intrude during the brooding^[9]
3. The eggshell could slip over the unhatched egg, creating a double shell^[9]
4. Some of the moist organic material left from the shell could lead to a production of bacteria and mould^[9]

Breeding

Begging coordination between siblings

Black-headed gulls feed their young by regurgitating onto the ground, rather than into each chick one at a time. The parents tend to accommodate their regurgitation amounts for how intense the nest begging is, from both an individual chick or a group of chicks begging together. Chicks who are siblings, have learned this behaviour and begin synchronizing their begging signals to decrease the costs as an individual and increase the benefits as a whole.^[12] The rate of parental food regurgitation to chicks increases with begging intensity.^[13]

The amount and response of begging signals differs throughout the nestling period. Usually, there are 3-5 begging events/hour, each lasting around one minute.^[12] High intensity begging behaviour appears at the end of the first week in the nest, but the coordination between multiple chicks emerge during the last week of the nestling period. The more siblings present, the more they coordinate their begging while decreasing the number of begging.^[12]

Sex differences

Male chicks have less of a chance of survival when compared to female chicks. Black-headed gulls are a sexually size-dimorphic species, so the larger sex is at a disadvantage when the amount of food sources are low.^[14]

Male birds are more likely to be born in the first egg and female birds are more likely to be born in the third. The position of a female black-headed gull in response to the food available when laying the eggs can predict the offspring's characteristics.^[15]

Conspecific brood parasitism

Conspecific brood parasitism is a behaviour that occurs when females lay their eggs in another female’s nest, of the same species.^[16] It can reduce the cost of incubation and nestling young by passing it on to another bird. Black-headed gulls usually lay three egg clutches, and the first two are normally larger than the third.^[16] The third egg normally has the lowest survival rate, while the first or second are usually the parasitic eggs.^[16]

Most of the egg dumping occurs within the beginning of the egg laying period. The parasitic eggs being laid in another conspecific’s nest increases the chance of hatching and may occur because of nest desertion or a nest being taken over by another bird.^[16]

Multiple eggs in a nest from different mothers may also result from intra-specific nest parasitism,^[17] joint female nesting,^[18] and nest takeover.^[19] Intra-specific nest parasitism is a disadvantage to the hosts because the female could end up taking care of the parasitic chicks over her own and therefore neglecting them and reducing their fitness. Another disadvantage for the host is that incubating more chicks than their own takes up more energy.^[20]

Extra-pair paternity

The rate of extra-pair paternity (EPP) has a large variation between populations of black-headed gulls. It is primarily a context-dependent strategy, meaning not all black headed gulls experience this behaviour.^[21] The variation between populations of extra-pair paternity can be explained by the variation it has on the advantages and disadvantages it has on a female, as well, as the variation in pressure on a females choice.^[22]

The differences in the rate of EPP may be determined by multiple different factors: life history traits, ecological factors or different behavioural strategies of males.^[21]

Central–periphery gradient within colonies

Egg-laying can be earlier in Black-headed Gulls nesting in the centre of the colony, with central pairs tending to lay larger eggs, which have a higher hatching success, than pairs nesting at the periphery of the colony. Centrally nesting individuals have also been found to be in better condition and have higher genetic quality.^[23]

Walking displays

Black-headed gulls display both head-bobbing walking (HBW) and non-bobbing walking (NBW). Head-bobbing walking is expressed by a hold phase and a thrust phase. The hold phase in black-headed gulls occurs mainly during the single support phase and is when the bird balances its head to equal the environment.^[24] Head-bobbing walking occurs during a seeking type foraging by walking through water and includes benefits such as enhancing motion and pattern detection and gathering depth information from motion parallax during the thrust phase.^[24] Non-bobbing walking occurs when black-headed gulls are displaying a waiting behaviour while foraging on flat surfaces.^[24]

Uses

 

Eggs, Collection Museum Wiesbaden, Germany

The eggs of the black-headed gull are considered a delicacy by some in the UK and are eaten hard boiled.^[25][26] The collection of black-headed gull eggs is heavily regulated by the UK government. Eggs may only be taken by a small number of licensed individuals at six sites between April 1 and May 15 each year and only a single egg may be taken from each nest. No eggs are permitted to be sold after June 30. As the gulls tend to lay in late April and early May, the eggs are only available to purchase for 3 or 4 weeks per year.^[27]

Synchronization

Observations on the behavior of black-headed gulls show that black-headed gulls individuals synchronize their vigilance activity with other black-headed gulls neighbors. Synchronization in black-headed gulls groups is dependent on the distance between the black-headed gulls members.^[28]

Australian discovery

On 19th October 1991, local Broome birder Brian Kane saw a strange species of bird while trawling the local sewer ponds. Upon seeing this bird, he contacted the Broome Bird Observatory by telephone to verify the species, however there was conjecture regarding its identity. Kane took photos of the bird and recorded field notes, before sending this information to the Appraisals Committee in Hobart, Tasmania, who were able to confirm that it was indeed a black-headed gull. This was the first recorded sighting of the species in Australia.^[29]

In popular culture

In Richard Adams' 1972 novel Watership Down, a black-headed gull named Kehaar (who claims his name is the onomatopoeia of waves breaking against the shore) plays a major part in the story. Injured by a farm cat and left behind during the seasonal migrations, Kehaar finds himself stranded on the Downs and is taken in by a warren of European rabbits. He later becomes their friend and ally, and helps to save the rabbits from danger many times; instincts eventually force him to return to his colony, but he promises to visit the rabbits each winter. ^{[30] [31] [32]} True to Adams' stated intentions of trying to keep the animals' behavior close to reality, Kehaar is characterized as intelligent, gregarious, noisy, messy, and impatient. He has a guttural accent, inspired by a Norwegian Resistance fighter Adams once had known.^[33] Kehaar appears in all three screen adaptations of the novel; the character was voiced by Zero Mostel in the 1978 film, Rik Mayall in the 1999 TV series, and Peter Capaldi in the 2018 miniseries.

The black-headed gull is the official bird of Tokyo, Japan,^[34] and the Yurikamome automated guideway transit in Tokyo Bay is named after it.^[35]

Gallery

•  

  mating

•  

  nesting and with chicks

•  

  Ringing of black-headed gull Chroicocephalus ridibundus (Linnaeus, 1766) (Laridae) nestling

•  

  Adult winter plumage in St James's Park, London

•  

  Adult breeding plumage

•  

  Juvenile plumage

•  

  In flight

•  

  Juvenile at Farmoor Reservoir, Oxfordshire

•  

  At Farmoor Reservoir, Oxfordshire

•  

  First winter plumage, at Blenheim Palace, Oxfordshire

•  

  ID composite

•  

  In flight near Großenbrode, Schleswig-Holstein. The bird is in a near-vertical position.

•  

  From Navi Mumbai, India

•  

  Ringed adult in summer.

•  

  Juvenile first winter.

• Black-headed gulls forages on insects.

References

1. Butchart, S.; Symes, A. (2012). "Larus ridibundus". IUCN Red List of Threatened Species. 2012: e.T22694420A38851158. doi:10.2305/IUCN.UK.2012-1.RLTS.T22694420A38851158.en.
2. Jobling, James A (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp. 104, 171. ISBN 978-1-4081-2501-4.
3. Scott, Paul; Duncan, Peter; Green, Jonathan A. (2 January 2015). "Food preference of the Black-headed Gull Chroicocephalus ridibundus differs along a rural–urban gradient". Bird Study. 62 (1): 56–63. doi:10.1080/00063657.2014.984655. ISSN 0006-3657. S2CID 84645998.
4. Peterson, R., Mountfort, G. and Hollom, P.A.D.1967. A Field Guide to the Birds of Britain and Europe. Collins
5. "Black-Headed Gull | Bird Spot". 24 August 2017. Retrieved 13 June 2021.
6. "Longevity, ageing, and life history of Chroicocephalus ridibundus". The Animal Ageing and Longevity Database. Retrieved 27 September 2015.
7. Attenborough, D. 1998. The Life of Birds. BBC ISBN 0563-38792-0
8. SORDAHL, TEX A. (2006). "Field Experiments on Eggshell Removal by Mountain Plovers". The Wilson Journal of Ornithology. 118 (1): 59–63. doi:10.1676/1559-4491(2006)118[0059:feoerb]2.0.co;2. ISSN 1559-4491. S2CID 84953154.
9. Houghton, J.C.W.; Feekes, F.; Broekhuysen, G.J.; Tinbergen, N.; Szulc, E.; Kruuk, H. (1962). "Egg Shell Removal By the Black-Headed Gull, Larus Ridibundus L.; a Behaviour Component of Camouflage". Behaviour. 19 (1–2): 74–116. doi:10.1163/156853961x00213. ISSN 0005-7959.
10. Beer, C.G. (1963). "Incubation and Nest-Building Behaviour of Black-Headed Gulls Iv: Nest-Building in the Laying and Incubation Periods". Behaviour. 21 (3–4): 155–176. doi:10.1163/156853963x00158. ISSN 0005-7959.
11. Tinbergen, N.; Broekhuysen, G.J.; Feekes, F.; Houghton, J.C.W.; Kruuk, H.; Szulc, E. (1962). "Egg shell removal by the Black-headed Gull Larus ridibundus L.; A Behaviour Component of Camouflage". Behaviour. 19 (1/2 (1962)): 71–117. doi:10.1163/156853961X00213. ISSN 0005-7959.
12. Blanc, Alain; Ogier, Nicolas; Roux, Angélique; Denizeau, Sébastien; Mathevon, Nicolas (2010). "Begging coordination between siblings in Black-headed Gulls". Comptes Rendus Biologies. 333 (9): 688–693. doi:10.1016/j.crvi.2010.06.002. ISSN 1631-0691. PMID 20816649.
13. Mathevon, N.; Charrier, I. (7 May 2004). "Parent–offspring conflict and the coordination of siblings in gulls". Proceedings of the Royal Society of London. Series B: Biological Sciences. 271 (suppl_4): S145–S147. doi:10.1098/rsbl.2003.0117. ISSN 0962-8452. PMC 1810040. PMID 15252967.
14. MULLER, WENDT; GROOTHUIS, TON G. G.; EISING, CORINE M.; DIJKSTRA, COR (2005). "An experimental study on the causes of sex-biased mortality in the black-headed gull - the possible role of testosterone" (PDF). Journal of Animal Ecology. 74 (4): 735–741. doi:10.1111/j.1365-2656.2005.00964.x. ISSN 0021-8790.
15. Lezalova, Radka; Tkadlec, Emil; Obornik, Miroslav; Simek, Jaroslav; Honza, Marcel (7 September 2005). "Should males come first? The relationship between offspring hatching order and sex in the black-headed gull Larus ridibundus". Journal of Avian Biology: 060118052425010––. doi:10.1111/j.2005.0908-8857.03466.x. ISSN 0908-8857.
16. Duda, Norbert; Chętnicki, Włodzimierz (2012). "Conspecific Brood Parasitism is Biased Towards Relatives in the Common Black-Headed Gull". Ardea. 100 (1): 63–70. doi:10.5253/078.100.0110. ISSN 0373-2266. S2CID 86227635.
17. YOM-TOV, YORAM (28 June 2008). "An updated list and some comments on the occurrence of intraspecific nest parasitism in birds". Ibis. 143 (1): 133–143. doi:10.1111/j.1474-919x.2001.tb04177.x. ISSN 0019-1019.
18. Vehrencamp, Sandra L. (2000). "Evolutionary routes to joint-female nesting in birds". Behavioral Ecology. 11 (3): 334–344. doi:10.1093/beheco/11.3.334. ISSN 1465-7279.
19. Waldeck, Peter; Andersson, Malte (2006). "Brood Parasitism and Nest Takeover in Common Eiders". Ethology. 112 (6): 616–624. doi:10.1111/j.1439-0310.2005.01187.x. ISSN 0179-1613.
20. Duda, Norbert; Ch e ˛ tnicki, Wlodzimierz; Waldeck, Peter; Andersson, Malte (7 January 2008). "Multiple maternity in black-headed gull Larus ridibundus clutches as revealed by protein fingerprinting". Journal of Avian Biology: 080205233540538–0. doi:10.1111/j.2007.0908-8857.04111.x. ISSN 0908-8857.
21. Indykiewicz, Piotr; Podlaszczuk, Patrycja; Minias, Piotr (2017). "Extra-pair paternity in the black-headed gull: is it exceptional among colonial waterbirds?". Behaviour. 154 (11): 1081–1099. doi:10.1163/1568539x-00003459. ISSN 0005-7959.
22. Petrie, Marion; Kempenaers, Bart (1998). "Extra-pair paternity in birds: explaining variation between species and populations". Trends in Ecology & Evolution. 13 (2): 52–58. doi:10.1016/s0169-5347(97)01232-9. ISSN 0169-5347. PMID 21238200.
23. Indykiewicz, P.; Podlaszczuk, P.; Kamiński, M.; Włodarczyk, R.; Minias, P. (2019). "Central–periphery gradient of individual quality within a colony of Black‐headed Gulls". Ibis. 161 (4): 744–758. doi:10.1111/ibi.12689. S2CID 91379509.
24. Fujita, Masaki (24 January 2006). "Head-bobbing and non-bobbing walking of black-headed gulls (Larus ridibundus)". Journal of Comparative Physiology A. 192 (5): 481–488. doi:10.1007/s00359-005-0083-4. ISSN 0340-7594. PMID 16432727. S2CID 23321265.
25. Copping, Jasper (28 March 2009). "Top restaurants face shortage of seagull eggs". The Daily Telegraph. London.
26. "Conservation (Natural Habitats&c" (PDF). Archived from the original (PDF) on 14 April 2010.
27. "Gull's Eggs: A Chef's Guide". First Choice Produce. 30 March 2019. Retrieved 13 January 2021.
28. Evans, M. H. R., Lihou, K. L., Rands, S. A. “Black-Headed Gulls Synchronise Their Activity with Their Nearest Neighbours.” Scientific Reports, vol. 8, no. 1, 2018, doi:10.1038/s41598-018-28378-x.
29. "Black-headed Gull at the Broome Sewage Ponds".
30. Adams, Richard. "Chapter 23: Kehaar". Watership Down, Scribner U.S. edition, 2005. ISBN 0-7432-7770-8.
31. Adams, Richard. "Chapter 38: The Thunder Breaks". Watership Down, Scribner U.S. edition, 2005. ISBN 0-7432-7770-8.
32. Adams, Richard. "Chapter 40: The Way Back". Watership Down, Scribner U.S. edition, 2005. ISBN 0-7432-7770-8.
33. Adams, Richard. "Introduction". Watership Down, Scribner U.S. edition, 2005. ISBN 0-7432-7770-8.
34. "Tokyo's Symbols". Tokyo Metropolitan Government. Retrieved 25 May 2020.
35. University of Michigan. "Developing Metros". Developing Metros: A Railway Gazette International Publication. Transport Press: 6. 1996. ISSN 0268-5590. OCLC 12264501.{{cite journal}}: CS1 maint: others (link)

External links

 

Wikimedia Commons has media related to Chroicocephalus ridibundus.

 

Look up black-headed gull in Wiktionary, the free dictionary.

• Black-headed gull stamps from many countries at bird-stamps.org
• Feathers of Black-headed Gull (Larus ridibundus) at Ornithos.de
• BirdLife species factsheet for Larus ridibundus
• "Chroicocephalus ridibundus". Avibase.  
• "Common black-headed gull media". Internet Bird Collection.
• Black-headed gull photo gallery at VIREO (Drexel University)
• Interactive range map of Larus ridibundus at IUCN Red List maps
• Audio recordings of Black-headed gull on Xeno-canto.
• Chroicocephalus ridibundus in Field Guide: Birds of the World on Flickr
• media from ARKive  
• Article with video about Black-Headed Gull at avibirds.com