Little tern
Common name: Little tern
Scientific name: Sterna albifrons
Conservation status: This species is classified as 'Endangered' in Queensland under the Nature Conservation Act 1992.
Description: This is the smallest tern in the Australasian region, but is very similar in size, shape and plumage to the fairy tern, Sterna nereis. Its length is 20-28cm and its wingspan is 45-55cm. The tail is moderately long and forked, and is slightly shorter than the wing-tips when the bird is at rest. It has a distinctive breeding plumage with black crown and nape and narrow black wedge from eye to bill. Its white forehead extends back over the eye as a narrow eyebrow, and its bill and legs are yellow. Its bill usually has a black tip. The sexes are indistinguishable. Non-breeding birds have a black bill and legs, with a greatly receded black crown.
Habitat and distribution: The little tern is mainly found in coastal environments, including beaches, sheltered inlets, estuaries, lakes, bays and harbours, especially where exposed sandbanks or sand spits occur. It is sometimes found on offshore continental islands or coral cays. Breeding habitat includes sand spits or islets in sheltered coastal environments such as estuaries and inlets, and also sandy ocean beaches, with nests occasionally built in sand dunes. It may also occasionally nest on coral cays.
Its distribution includes all continents. In Australia, it occurs in all coastal areas except the south-west and southern parts of Western Australia, the western half of South Australia and western shores of Tasmania. It is scarce in south-eastern Australia in winter, apparently because Asian birds depart to breed and local birds migrate north along coast.
Behaviour and life history: The little tern usually feeds in small groups, although it often roosts in large flocks on beaches or sand spits with other terns. It is active and noisy; its usual flight call is an excited, high-pitched 'kweek'. Its alarm call is an urgent 'tee-eep, tee-eep, tee-eep'. The little tern flies with deep, rapid wingbeats and hovers rapidly with wings held in steep 'V' before it plunges into the water when feeding. Breeding colonies are surprisingly unobtrusive and easily overlooked.
The little tern breeds from May to July in the Gulf of Carpentaria, and mostly from September to January along the east coast. This species lays eggs directly on the sand. Laying does not occur at the same time, even within individual breeding colonies. Clutch size is one to three, incubation period is 17-25 days. Chicks are mobile very soon after hatching and leave the nest almost at once. The fledging period (hatching to maturity) is 17-19 days.
Threatening processes: Threats known to affect the little tern include coastal recreational activities such as 4WD vehicles on the beach, trail bike riding and walking that can crush eggs and chicks. Foxes, wild dogs and uncontrolled pet dogs are the most serious predators, along with cats, rats and silver gulls. Human disturbance is also a major cause of nest failure. Loss of suitable nesting habitat occurs because of recreational use or development. Little terns are potentially susceptible to pesticides and contamination of estuaries by oil spills and heavy metals.
Recovery actions:
- Major breeding sites in Queensland need to be identified or verified.
- Feral animals, including cats and foxes, need to be controlled at known sites.
- Education (including signage) at known sites is essential so that visitors aware of the impacts of their activities. Drivers of vehicles on beaches are requested to stay clear of nesting areas.
Further information:
Stephen T. Garnett S.T and Crowley G.M. 2000. The Action Plan for Australian Birds (PDF)*. Environment Australia, Canberra.
* Requires Acrobat Reader
Last updated: 31 August 2006