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| [Note Guidelines] Photographer's Note |
Wrybill (Anarhynchus frontalis)
Early in the 19th century, this species was recorded in flocks of thousands. It has certainly declined since then to a small population overall, and available evidence suggests that the decline is ongoing, thereby qualifying it as Vulnerable.
Identification: 20 cm. Stocky, pale grey plover, tip of black bill turned to right. Ash-grey crown, nape, upperparts. White underparts. Black band across upper chest thick in breeding male, thinner in breeding female, sometimes absent in non-breeding birds. Black frontal band above white forehead in male, absent in female. Juvenile breast-band absent, back feathers tinged with white. Voice Short, clear weet.
Range & population: Anarhynchus frontalis breeds in Canterbury and Otago, South Island, New Zealand. It is found in over 26 riverbeds, but is only common on 10. It winters mainly north of 38°S in the North Island. In the last 40 years, population counts have varied between 3,000 and 5,000 individuals, probably reflecting the difficulty in surveying the species. Analysis of wintering flocks indicates a slow decline over this period, which is supported by preliminary results from a long-term demographic study.
Ecology: It breeds on braided riverbeds, and frequents sheltered estuaries and coasts over the non-breeding season. Nests are built within 250 m of running water, and are usually hollows in bare shingle, lined with more than 100 small pebbles. It lays two eggs. Young usually begin to breed at two or three years of age. Mark-recapture of almost 2,400 birds indicates that many live past 10 years of age, the average adult life expectancy is c.5.4 years. Diet comprises mostly mayflies and caddisflies, but is more general when rivers are in flood.
Threats: Breeding habitat is deteriorating, primarily from the encroachment of weeds as hydroelectric schemes reduce seasonal flushing of riverbeds. The extent of predation by stoat Mustela erminea and cats has not been quantified, but is likely to be substantial. The recent illegal introduction of Rabbit Haemorrhagic Disease has resulted in the localised switching of some predators to a diet consisting of more birds. Predation by Kelp Gull Larus dominicanus may pose an increasing threat as it becomes more numerous in association with human activities. Increasing use of riverbeds for recreational purposes and floods are also threats.
The above obtained from http://www.birdlife.org/datazone/ebas/index.html?action=SpcHTMDetails.asp&sid=3149&m=0
IMAGE INFORMATION
Camera: Canon 1D Mk lll
Time of day: 6:11 p.m.
Date: 29th December 2007
Weather conditions: Clear
Lens: Canon 100-400mm L IS USM
Filter: Hoya 77mm UV
Shutter Speed: 1/640
F-Stop: F/14
Focal Length: 400mm
ISO: 400
Support: Hand Held
Original file type: Digital Raw |
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Hi Pam,
Good composition.Great shot with excellent detail