Ferret caught within 150 metres of wrybill population

Photo taken yesterday shows a ferret caught within 150 metres of the main population of wrybills on the South Branch of the Ashburton River. The ferret was caught right in the centre of an area where breeding banded dotterels are located.

Wrybills- often look skyward

Wrybills seem to be easily alarmed by any shadows over them. There is increasing concern about the potential impact of the increasing numbers of black-backed gulls on the wrybill population. Gulls may be major predators of wrybill chicks but there is little direct evidence to support this idea.

wrybill taking off- Avon-Heathcote Estuary

wrybill sex ratios

There is some concern that as male wrybills sit on the nest during low light periods ( dawn and dusk) and through the night, and females on the nest during the day- (as a rule of thumb on rivers that are monitored) - that male wrybills may be more vulnerable to mammalian predation.

I have no hard data analysed yet to support this hypothesis- but it would be relevant to investigate. If anyone is looking through wrybill flocks on their southward migration could they please record the number of males and number of females . Please email to me at langlands@xtra.co.nz
Note Male wrybills have a distinct solid black line on their forehead, females do not.
photograph of male bird shown .
Thanks
Peter

Nelson Tasman Branch Wrybill Watch

Nelson Tasman Branch Wrybill Watch
A noon high tide at Nelson in mid August saw twenty five members of Nelson-Tasman Branch of Forest & Bird braving the cool thigh deep water of the Waimea Estuary. Led by ornithologist Willie Cook, this was no mid-winter fun dip but a necessary wade to gain access to a spit of land from which a group of distant transients might be viewed. The transients in question were some thirty wrybills. This New Zealand endemic bird overwinters on the mudflats of North Island harbours and returns to its nesting grounds of the South Island braided river shingle during late winter. The Waimea estuary provides a good rest point in that migratory journey. The wrybill derives its name from its rightward laterally twisted bill; a feature unique to its species. Current population estimates are between 3,000 and 5,000 individuals and surveys seem to agree that bird numbers are declining. The most likely causes of the decline are loss of habitat through weed encroachment (eg.lupins) and the effects of hydroelectric and irrigation schemes, and predation by mustelids. The wrybill shows a remarkable tolerance to the presence of man, another factor which may not be helpful in its bid to survive but, on the positive side, allowed us to enjoy its visit.

http://www.facebook.com/profile.php?id=655388324#!/ForestandBird?ref=mf

Extracted from Forest and Birds Facebook page- 010910-