Higher call rates of morepork, Ninox novaeseelandiae, at sites inside an area with ongoing brodifacoum poisoning compared with matched non‐managed sites

In Ark in the Park, a conservation project in the Waitakere ranges near Auckland, New Zealand, the anticoagulent brodifacoum has been used as a principal means of ongoing rodent pest eradication since 2003. The morepork (Ninox novaeseelandiae) is a small species of owl at risk of secondary poisoning through ingestion of poisoned invertebrates and rodents. To begin to examine whether morepork are being affected by the continued poisoning operation, we conducted call counts in December 2006 and January 2007. We collected data on morepork calls inside the poison‐operation area (Ark in the Park) and compared their rate and direction with calls recorded at date‐matched control locations in the Waitakere ranges where no poisoning was conducted. Despite small sample sizes, there were significantly more calls, call bouts, and estimated numbers of morepork inside Ark in the Park compared with the control sites outside. If higher call rates, in the face of ongoing brodifacoum application, represent higher densities of morepork inside Ark in the Park compared to nearby non‐managed sites, then we suggest that these results imply a higher quality of foraging habitats and breeding grounds inside the conservation area following the reduction in population sizes of mammalian pests.