In late April 2016 we checked the sooty colony again with the burrowscope. The sooty chicks would be fledging in early May and if there were healthy chicks present in late April, then they would probably have had their last parental feed and would be likely to fledge successfully.
We found 16 healthy sooty chicks, in various states of down coverage, but all looking good. Down coverage is a misleading method of aging chicks and a single wet night on the surface can turn a fluffball into a bird that looks ready to go.
Not only was 16 a vast improvement on last year’s presumed 3 fledges, it was from 20 active burrows (of 30 known burrows) at egg-laying time in late November. This is a high success rate and implies that all was well at the colony with respect to weka predation and any other adverse factors beyond our knowledge.
Weka numbers were a bit lower this year than last, but we did not see any evidence of successful weka predation last year either. I guess some at-sea event, such as food concentrations moving further south than expected, might have explained last year’s result.
Can we ease up on weka-catching therefore? Quite possibly with respect to the sooties, but not if we are hoping that any of the smaller seabirds like fluttering shearwater, fairy prion or diving petrel will establish.