Gannet

Gannet
Gannet
Northern Gannets on Heligoland, a small German archipelago in the North Sea
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Suliformes
Family: Sulidae
Genus: Morus
Linnaeus, 1753
Species
  • Morus bassanus
  • Morus capensis
  • Morus serrator
Synonyms

Moris

Nesting gannets (Morus serrator) at the Muriwai colony in New Zealand

Gannets are seabirds comprising the genus Morus, in the family Sulidae, closely related to the boobies.

The gannets are large black and white birds with yellow heads. They have long pointed wings and long bills. Northern gannets are the largest seabirds in the North Atlantic, with a wingspan of up to 2 metres. The other two species occur in the temperate seas around southern Africa, southern Australia and New Zealand.

Gannets hunt fish by diving from a height into the sea and pursuing their prey underwater. Gannets have a number of adaptations which enable them to do this:

  • they have no external nostrils;
  • they have air sacs in their face and chest under their skin which act like bubble wrapping, cushioning the impact with the water;
  • their eyes are positioned far enough forward on their face to give them binocular vision, allowing them to judge distances accurately.

Gannets can dive from a height of 30 m, achieving speeds of 100 km/h as they strike the water, enabling them to catch fish much deeper than most airborne birds.

The gannet's supposed capacity for eating large quantities of fish has led to "gannet" becoming a disapproving description of somebody who eats excessively, similar to "glutton".

Contents

Mating and nesting

Gannets are colonial breeders on islands and coasts, normally laying one chalky, blue egg. It takes five years for gannets to reach maturity. First-year birds are completely black, and subsequent sub-adult plumages show increasing amounts of white.

The most important nesting ground for Northern gannets is the United Kingdom with about two thirds of the world's population. These live mainly in Scotland, including the Shetland Isles. The rest of the world's population is divided between Canada, Ireland, Faroe Islands and Iceland, with small numbers in France (they are often seen in the Bay of Biscay), the Channel Islands and Norway. The biggest Northern gannet colony is in the Scottish islands of St Kilda; this colony alone comprises 20% of the entire world's population. Sulasgier off the coast of the Isle of Lewis, Bass Rock in the Firth of Forth, Grassholm in Pembrokeshire and Bonaventure Island, Quebec are also important Northern gannet breeding sites.

The Skellig Islands off the south-west coast of Ireland hold some 27,000 pairs of Northern Gannets, the second largest colony in the world.

Systematics and evolution

The three gannet species are now usually placed in the genus Morus, Abbott's Booby in Papasula, and the remaining boobies in Sula. However, some authorities believe that all nine sulid species should be considered congeneric, in Sula. At one time, the various gannet species were considered to be a single species.

Most fossil gannets are from the Late Miocene or Pliocene, a time when the diversity of seabirds in general was much higher than today. It is not completely clear what caused the decline in species at the end of the Pleistocene; increased competition due to the spread of marine mammals and/or supernova activity which led to mass extinctions of marine life are usually assumed to have played a role.

The genus Morus is much better documented in the fossil record than Sula, though the latter is more numerous today. The reasons are not clear; it might be that boobies were better-adapted or simply "lucky" to occur in the right places for dealing with the challenges of the Late Pliocene ecological change, or it could be that many more fossil boobies still await discovery. Notably, gannets are today restricted to temperate oceans while boobies are also found in tropical waters, whereas several of the prehistoric gannet species had a more equatorial distribution than their congeners of today.

Fossil species of gannets are:

  • Morus loxostylus (Early Miocene of EC USA)—includes M. atlanticus
  • Morus olsoni (Middle Miocene of Romania)
  • Morus lompocanus (Lompoc Late Miocene of Lompoc, USA)
  • Morus magnus (Late Miocene of California)
  • Morus peruvianus (Pisco Late Miocene of Peru)
  • Morus vagabundus (Temblor Late Miocene of California)
  • Morus willetti (Late Miocene of California)—formerly in Sula
  • Morus sp. (Temblor Late Miocene of Sharktooth Hill, USA: Miller 1961)—possibly M. magnus
  • Morus sp. 1 (Late Miocene/Early Pliocene of Lee Creek Mine, USA)
  • Morus sp. 2 (Late Miocene/Early Pliocene of Lee Creek Mine, USA)
  • Morus peninsularis (Early Pliocene)
  • Morus recentior (Middle Pliocene of California, USA)
  • Morus reyanus – Del Rey Gannet (Late Pleistocene of W USA)

Popular culture

Gannet in the Celtic Sea - Ireland
  • In many parts of the United Kingdom, the term Gannet is used to refer to people that steadily eat vast quantities of food especially at public functions.
  • Young gannets were historically used as a foodsource, a tradition still practised in Ness, Scotland, where they are called 'guga'.
  • The Gannetwhale is a hypothetical descendant of the gannet seen in the television show The Future Is Wild.

References

  • Miller, Loye H. (1961): Birds from the Miocene of Sharktooth Hill, California. Condor 63(5): 399-402. PDF fulltext

External links


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Synonyms:
, , (Sula bassana)


Look at other dictionaries:

  • Gannet — Gan net, n. [OE. gant, AS. ganet, ganot, a sea fowl, a fen duck; akin to D. gent gander, OHG. ganazzo. See {Gander}, {Goose}.] (Zo[ o]l.) One of several species of sea birds of the genus {Sula}, allied to the pelicans. [1913 Webster] Note: The… …   The Collaborative International Dictionary of English

  • gannet — O.E. ganot gannet, sea bird, water fowl, from P.Gmc. *ganito (Cf. Du. gent, M.H.G. ganiz, O.H.G. ganazzo), from PIE *ghans (see GOOSE (Cf. goose)). O.Fr. gante is from Germanic …   Etymology dictionary

  • gannet — [gan′it] n. pl. gannets or gannet [ME ganat < OE ganot, solan goose, lit., a gander, akin to Du gent, OHG ganazzo, gander: for IE base see GOOSE] any of a genus (Morus, family Sulidae) of pelecaniform birds; esp., a white, gooselike, web… …   English World dictionary

  • Gannet — Gannet, so v.w. Bassansgans …   Pierer's Universal-Lexikon

  • gannet — ► NOUN 1) a large seabird with mainly white plumage, catching fish by plunge diving. 2) Brit. informal a greedy person. ORIGIN Old English, related to GANDER(Cf. ↑gander) …   English terms dictionary

  • Gannet — Gannett oder Gannet hat verschiedene Bedeutungen: Gannett Peak, der höchste Punkt in Wyoming Fairey Gannet, ein britisches Kampfflugzeug Gannett Company, Inc., ein US amerikanischer Medienkonzern Frank E. Gannett, Gründer des Gannett… …   Deutsch Wikipedia

  • gannet — /gan it/, n. any large, web footed, seabird of the family Sulidae, having a sharply pointed bill, long wings, and a wedge shaped tail, noted for its plunging dives for fish. [bef. 900; ME; OE ganot; akin to D gent GANDER] * * * Any of three… …   Universalium

  • gannet — [OE] The gannet used to be known dialectally as the solan goose (solan was a compound formed in the 15th century from Old Norse súla ‘gannet’ and önd ‘duck’), and in fact the name gannet too reveals a perceived similarity between the gannet and… …   The Hutchinson dictionary of word origins

  • gannet — [OE] The gannet used to be known dialectally as the solan goose (solan was a compound formed in the 15th century from Old Norse súla ‘gannet’ and önd ‘duck’), and in fact the name gannet too reveals a perceived similarity between the gannet and… …   Word origins

  • gannet — /ˈgænət / (say ganuht) noun any of three large pelagic birds of the family Sulidae, as the cape gannet, Morus capensis, found in oceans off southern Africa. See Australasian gannet, northern gannet. {Middle English and Old English ganet, related… …  

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