19 June 2008

Christchurch City Council’s efforts to protect and restore the natural environment are getting a lot of attention lately - and not just from the city’s human inhabitants.

Two rare bird species have been found at opposite ends of the Styx River within a day of each other.

A White Heron has taken up residence at Styx Mill Basin Reserve, and a juvenile Australasian Crested Grebe has appeared at the mouth of the Styx River in Brooklands Lagoon.

The White Heron, or Kotuku, has made a home for itself in an area where park rangers have been planting thousands of native trees and shrubs as part of a bush and wetland restoration project. This work has included the creation of three wildlife lakes, expansion of core wetland areas and development of native bush patches.

The White Heron, or Kotuku, has made a home for itself in an area where park rangers have been planting thousands of native trees and shrubs as part of a bush and wetland restoration project. This work has included the creation of three wildlife lakes, expansion of core wetland areas and development of native bush patches.

The heron was spotted on Tuesday, 10 June, by Park Rangers John Parry and Bill Stevenson and Environmental Education Teacher Jessica Brocas, who were escorting a group of students from Harewood School.

The bird is the first White Heron recorded at the Styx Mill Basin and is the 49th species of bird recorded at the reserve.

White Herons breed at a colony on the Waitangiroto River, near Okarito Lagoon in Westland. After breeding they disperse throughout the country and usually live alone through autumn and winter. The oldest White Herons are known to live up to 22 years.

In the 1980s and 90s, a locally famous White Heron spent its winters on the Linwood Avenue Canal and Travis Wetland. It appeared in the area without fail for 14 consecutive years before it disappeared, and presumably died of old age.

The Australasian Crested Grebe, or Puteketeke, is usually a resident of high country lakes but seems to be making itself at home in the tidal environment of Brooklands Lagoon. The juvenile was first spotted by Park Ranger Andrew Crossland on Wednesday, 11 June.

The species is one of our rarest and most-threatened native waterbirds, with a total population of only about 430 birds. Its range is typically restricted to a small number of lakes in Canterbury, Otago, Westland and Fiordland.

Crested Grebes were first recorded on waterways in the Christchurch area in 1849, prior to the arrival of the first four ships, and were probably locally common in pre-European times.

Like many waterbirds they were hunted by early settlers and suffered from predation and widespread destruction of their wetland habitats. By the 1880s Crested Grebes had disappeared from most lowland sites in Canterbury and survived only on the least disturbed high country lakes and tarns.

However, since the late 1980s these birds have been wintering on Lake Forsyth, and some have recently begun nesting on riverbanks.

It seems this highly endangered bird is beginning to disperse to similar habitats in the wider Central Canterbury area. Ornithologists are predicting that Crested Grebes might actually start colonising Christchurch waterways and wetlands in the next few years.

ENDS

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