Comment on “Population dynamics reveal conservation priorities of the threatened New Zealand sea lion Phocarctos hookeri” by Meyer, Robertson, Chilvers and Krkošek (2015)

Meyer et al. (2015) conclude that the population growth rate is most responsive to changes in survival of adult female Hookers or New Zealand sea lions (HSL), and that failure of measures intended to manage the incidental mortality of HSL in sheries could explain why the main population of [HSL] continues to decline. They claim that the New Zealand governments management of incidental HSL mortality is an exemplary case where management actions are implemented without quantifying the populations vulnerability to a threat. We disagree with all those conclusions. We argue that the data used are too limited and the modelling is too simplistic to estimate demographic parameters reliably. We suggest further that the authors misinterpreted their results. In any case, the management of sheries mortality has been thoroughly evaluated with respect to likely population effects.