The Wirebird census for 2009 took place during the month of January. In this month, thirty one Wirebird sites were surveyed across the island. These sites were originally identified by Dr Neil McCullough and by repeating surveys in the same areas every year we can estimate population size and make comparative assessments of population trends.  The total number of adult Wirebirds counted this year was 322.  This is 51 fewer adults than the 2008 census and represents a 13.7% decrease. This appears as a contrast to the similar increase witnessed last year.  It is possible however that there has been a move of birds from the main breeding sites into more semi-desert areas due to exceptional wet weather.  One of the areas we have seen a decrease in is Deadwood Plain from 66 to 47. Whilst we have seen an increase in numbers in the semi-desert Prosperous Bay Plain and Upper Prosperous Bay Plain areas, from 60 to 80.

In the first quarter of 2008 it was thought that the wet weather had a bearing on the larger than usual population of chicks and fledglings observed. Possibly because the food available to feral cats and myna birds [for instance] was more varied reducing the predation of Wirebird nests and may have also increased the availability of invertebrate food for Wirebird adults and young. However during the rest of the year we have seen Wirebirds leaving pasturelands and moving into the semi-desert areas. This is particularly notable on Deadwood where a combination of additional factors as well as the weather including, construction of the wind turbines and low grazing pressure has led to an increase in vegetation height. From our nest cameras in the field we have more data on rats, cats and myna birds and predation on Wirebirds continues to be a worrying factor. Fieldwork has also shown that disturbance from construction and off-road vehicles remains an issue.

Census counts have increased year on year since 2005/6. Although there is a significant decrease this year it is still felt that the main indicator from this years annual census is that the general trend for total numbers counted is potentially stabilising. A programme of ringing Wirebirds set up by Fiona Burns as part of her doctoral studies should help improve our understanding of Wirebird movements. Movement of Wirebirds into different areas when conditions are not ideal in their main breeding areas (predominantly pastures) might explain this year’s observed population decrease. Other areas throughout the island hold small pockets of Wirebirds but these are not included in the Census Counts, we are hoping to include these in next year’s counts and gather more information throughout the year to determine if Wirebirds may be breeding successfully in these areas.

The initial results from pasture improvement programmes established to help the Wirebird to breed successfully indicate that they can make a positive difference, however sustaining these benefits is a priority issue. 

The Conservation Officer and the SHNT would like to thank personally all those who helped with the count:
Andrew Darlow           Invasive Species Project Officer
Dr Tony Prater            RSPB, Wirebird Mitigation Project
Patrick Joshua            Nature Conservation Group
Fiona Burns                 Ph.D student, Bath University
Desmond Baggott       Building Contractor
Gillian Baggott             RSPB Events Project Manager
Susan Steptoe            RSPB Council Coordinator
Chris Dodd                  Warden Scottish Natural Heritage     
Lourens Malan            Horticultural Support Officer
Katrine  Herian            Conservation and Horticultural scholarship volunteer
Louise Blessington      National Trust volunteer
Dominic Hewes          National Trust volunteer
George Savill              National Trust volunteer

Gavin (Eddie Duff) Ellick
SHNT Conservation Officer Wirebird

Related Information

The Wirebird Project Page