The grey heron is a very large heron that is widely distributed across Europe, Asia and much of Africa. It has been recorded in New Zealand on a single occasion, when a first-year bird was captured on a yacht off the east coast of the North Island in about 1898. The specimen is held, along with the rest of Sir Walter Buller’s ‘third collection’, in Carnegie Museum, Pittsburgh, Pennsylvania.

Identification

A large heron; larger than white heron, with dark grey back, paler grey underparts, white head and neck with black streaking on front of neck, and black crest. In flight the dark grey body and forewings contrast with black flight feathers.

Voice: a harsh ‘frank’ given in flight, often when flushed.

Similar species: white-faced and reef heron are smaller (length 67 cm); white-faced heron is bluish-grey with a white face, reef heron is dull slaty blue-grey all over.

Distribution and habitat

The grey heron is widely distributed across Eurasia, with a small, isolated population breeding in Sumatra, Indonesia. They occur widely throughout freshwater and coastal wetlands.

Population/New Zealand records

A single record off the east coast of the North Island in about 1898. Walter Buller purchased the specimen in London, and subsequently sold it to the Carnegie Museum, where it remains.

The East Asian population of jouyi, the race thought to have occurred in New Zealand, is ‘guesstimated’ to be between 100,000 and 1,000,000, while the Sumatran population is only 1,000-2,000.

Threats and conservation   

Habitat destruction is adversely affecting grey herons in the Malay Peninsula, and probably elsewhere. Grey herons suffered badly from the pesticide DDT which caused eggshell thinning and low breeding success. DDT is still used in China and a growing number of other chemicals, such as fire retardants, are now polluting water bodies and may be affecting birds such as herons.

Breeding

Grey herons breed colonially, usually in trees, but occasionally on the ground. Usually 4 eggs are laid in a stick nest.

Behaviour and ecology

The northern East Asian population is strongly migratory, and is the most likely source of the New Zealand bird, in contrast to the more sedentary Malaysian Peninsula/Sumatran population.

Food

Mostly fish, particularly eels, but will also take a wide variety of other aquatic prey as well as small mammals and birds.

Weblinks

BirdLife factsheet

Wikipedia

References

Bartle, J.A.; Tennyson, A.J.D. 2009. History of Walter Buller’s collections of New Zealand birds. Tuhinga 20: 81-136.

del Hoyo, J.; Elliott, A.; Sargatal, J. (Eds.). 1992. Handbook of birds of the world. Vol. 1, ostrich to ducks. Lynx Edicions: Barcelona.

Heather, B.D.; Robertson, H.A. 1996. The field guide to the birds of New Zealand. Viking: Auckland.

Marchant, S.; Higgins, P.J. (Eds.). 1991. Handbook of Australian, New Zealand & Antarctic birds. Vol. 1, ratites to ducks. Oxford University Press: Melbourne.

McClure, H.E. 1974. Migration and survival of the birds of Asia. US Army Medical Component SEATO Medical Research Laboratory: Bangkok.

Wetlands International (2012). Waterbird population estimates, Fifth Edition. Summary Report. Wetlands International, Wageningen, The Netherlands

Wells, D.R. 1999. The birds of the Thai-Malay Peninsula. Vol. 1. Non-passerines. Academic Press: London.

Recommended citation

Melville, D.S. 2013. Grey heron. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz