Thursday, 23 August 2012

The Brown Creeper

by Derek Onley

Everyone's heard of kiwi. Most people will have seen a fantail. Many will have heard, if not seen, a morepork. Mention kaka and robin to anyone who has been out in the tamest of New Zealand bush and they will know what you are talking about. But ask if they've seen the brown creepers and even some of the keenest, most committed Orokonui volunteers will look at you blankly.


Strange, because around Dunedin, not only are they found in almost any bit of remnant bush bigger than Carisbrook, however scruffy, but they are also happy in pine plantations. (Now there's an idea: let's plant Carisbrook into lowland native forest.)  They are up in the low bush along the tussock edge in the Silverpeaks, and down in the strip of pine forest behind the beach at Waikouaiti. Though the odd wandering one might turn up in your garden for a few weeks in autumn, it is true that they haven't taken a liking to the suburbs and don't pile onto your bird feeders like silvereyes, but they do occur in the posher parts of the Dunedin town belt and there are lots in the Orokonui Ecosanctuary.


Not only are they common but they also tick all the other environmental and conservational boxes. They are endemic; not something that can be said for the better known fantail and morepork, both of which occur in Australia and the Pacific. And, furthermore, they occur only in the South Island -- a restricted range by any global conservation criteria. They are part of a distinctive, long-isolated and old New Zealand bird family that includes the North Island whitehead and the endangered mohua, and though they are able to adapt to a certain extent, they are essentially a forest and shrubland species, and as such in an agricultural country their habitat is never likely to be entirely secure.


So why are they not better known? Maybe it's the name -- 'brown creeper' hasn't exactly got a romantic or exciting ring about it. PeopIe have been heard to say: 'I'll just go up the valley to listen out for moreporks', or even 'I think I'll go for a walk up the Silverstream and look for robins'.  But brown creeper? It conjures up a little drab, mousy, unexciting bird that clings closely to tree trunks in impenetrable thickets, which is exactly the lifestyle of its American namesake, known in Europe as a tree creeper. New Zealand brown creepers are, in contrast, perky, active, busy little birds that bounce around, hang upside down and investigate every crevice, cranny and hole in a kanuka before scurrying off to the next, all the time calling to and yelling at their mates in the flock. Agreed, up the top of that kanuka, they do look brown -- few sparrow-sized birds wouldn't -- and yes, even close up you could still claim that the back, tail and wings are brown, but there's definitely some bright chestnut mixed in. The face is a clean, grey mask with a dash of white behind the eye, and the undersides, at the risk of spicing things up a little too much, could be described as pale cinnamon.


The Maori name pipipi doesn't help the image much, being but a somewhat unadventurous rendition of the call, though it does suggest that they are noisy, as indeed they are, constantly chattering in a scratchy, nasal way. Both males and females sing, often in a duet. The varied male song has been described as 'a phrase including slurs, musical whistles and harsh notes – chi-roh-ree-roh-ree-ree'! I suggest you would be better to listen to a recording or go out with someone who knows what they're talking about.


Brown creepers spend much of their lives in flocks; 20 or so is the usual size in the Orokonui. Nesting pairs defend territories but there are observations of other birds helping to feed the young.  Koekoea, long-tailed cuckoos, four  times as long and 10 times as heavy, lay their eggs in brown creepers' nests, and with the demise of all but a few mohua, brown creepers are now the commonest host in the South Island. But koekoea also require decent stands of mature native forest and haven't been recorded nesting in the Dunedin area for many years.


There are lots of brown creepers in the Orokonui. The regular bird surveys have found pre-fence averages per five minute count were the highest for any species: 2.5 per count in spring compared with 2.0 for their nearest rivals, bellbirds. Four years of fence have seen bellbird counts overtake those of brown creepers (around 1.0 compared with 4.0 for bellbirds last autumn) and there is an indication that brown creeper numbers are actually falling within the sanctuary while outside in the control areas, east over the Mopanui ridge and at Volco, counts remain much as they always were.


Surprising little birds, brown creepers.

1 comment:

Margie's Garden said...

Thank you for these notes. i would very much like to see and hear these birds one day. The related white-heads in our north island forests are lovely to listen to.