Saturday 6 June 2009

Conditions Suited to bird species Brown Treecreeper

Recently I had the pleasure of meeting Jane Paul at a field day at Bathurst. She is an avid birdwatcher and a member of NSW Bird Atlassers Inc. Subsequent to this meeting I’ve been corresponding with Jane, seeking information on what we may or may not have done here on Ochre Arch that has seen the exit from a small area in what we now call the Hopbush Paddock of the bird species Brown Treecreeper (Climacteris picumnus) which have a NSW conservation status of ‘Vulnerable’.

Jane referred my query to Neville Schrader from who is very knowledgeable of birds Parkes who responded and advised:
"The Brown Treecreeper is one of about 20+ woodland species considered to be decliners or put bluntly headed for extinction. This can be contributed to over clearing and habitat fragmentation. Reid in his study of Threatened and declining birds in the NSW wheat belt 1999, identified that Brown Treecreepers (and Hooded Robin) needed both standing and fallen. Ford noticed around Armidale that the distribution of Brown Treecreepers decreased westward by 40 to 60 km over 30 years. What he established was that small isolated populations in a fragment landscape were untenable and considered this to be due to power dispersal in such a landscape. This agrees pretty well what is happening in this area (Parkes) the first to go was the small family populations in fragmented habitat and by 1998 the larger state forests were starting to decline in population. So I’m inclined to think there are a number of factors. One would suspect that if vegetation growth was the problem because the species spends a lot of time on the ground feeding then the drought should have seen the species recover. If you may recall the only pair of brown Treecreepers we got on our outing at the Atlas camp at Grenfell had good ground cover so whilst I don’t completely reject that it may have some influence in good years, I believe that there are a number of factors that is causing this species any many others to decline. I put this down to habitat size, loss of vegetation complexity and structure, species competition, feral animals competition.”

We’ve looked at each of the factors Neville raised to see whether our decision making may have impacted on the exit of the Brown Treecreepers. Here are our thoughts:
Habitat size: If anything habitat size is now expanding on our place, although only marginally
Loss of vegetation complexity and structure: Now improving
Species competition: I don’t know what the competitors are, so cannot comment
Feral animals competition: This may well be the main factor. We’ve done nothing to control foxes since taking over the place … so they may be worse.

So … our not controlling fox numbers may well be the problem. We will be addressing this shortly in conjunction with staff from the Lachlan Livestock Health and Pest Authority. Let’s hope the Brown Treecreepers return!

Our thanks go to both Neville (gave permission to publish his comments) and Jane for their help and input, as above.

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