tomtit

Predation by mammals has been identified as the primary limiting factor of Aotearoa New Zealand native birds. Consequently, the ranges of many native forest bird species have contracted to cooler and higher elevation tracts of forest that support fewer introduced mammals. However, lower elevation forests are likely to be intrinsically more productive and able to sustain larger bird populations if control of mammalian pests removes predation as a primary limiting factor.

This study investigates the hypothesis that tomtits are significantly less susceptible to 1080 poison operations when cereal rather than carrot bait applications are used, both at relatively low sowing rates. We made counts of territorial male tomtits along transects during standard 1080 possum control operations in 2001 to 2003. The transects had 3Ð5 kg ha-1 sowing rates of either carrot or cereal baits.

The suitability of line-transect-based distance sampling to robustly estimate population densities of bellbird (Anthornis melanura), kererū (Hemiphaga novaeseelandiae), North island tomtit (Petroica macrocephala toitoi) and tūī (Prosthemadera novaeseelandiae) during concurrent multi-species surveys was investigated. Densities were estimated annually from 2006 to 2009 at three sites within the Coromandel Forest Park, New Zealand.