A census of variable oystercatcher (Haematopus unicolor) in the Marlborough Sounds
|Title||A census of variable oystercatcher (Haematopus unicolor) in the Marlborough Sounds|
|Publication Type||Journal Article|
|Year of Publication||2010|
|Type of Article||Full article|
|Keywords||breeding distribution, census, Marlborough Sounds, population estimate, variable oystercatcher|
A total of 730 variable oystercatchers (Haematopus unicolor) were recorded during a survey of the entire 1,500 km coastline of the Marlborough Sounds, New Zealand in spring 2006. This included 347 breeding pairs, 28 single birds and a non-breeding flock of 8 birds. The distribution of oystercatchers was influenced by habitat and human development, with fewer birds found in the inner sounds, where there is most development, and in the exposed outer coastline, where cliff or boulder habitat is limiting. Using similar methods of coastal surveys during the breeding season, the estimated national population of oystercatchers has increased from 2000 birds in 1970-71 to 7000 birds in 2006. This represents a population growth rate of 3.5% per annum. Winter flock counts give lower population estimates and coastal surveys are recommended for future monitoring of this species.