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The monitoring of endemic birds during the control of introduced mammalian predators is a common practice at community-based conservation projects in New Zealand. We describe long-term trends of endemic passerines monitored using the presence-absence technique during the control of stoats (
Mustela erminea) and brushtail possums (
Trichosurus vulpecula) in the Flora Valley, near Nelson, New Zealand. Data collected over an 8 year period by Friends of Flora, a community-based organisation, suggests that bellbirds (
Anthornis melanura) significantly increased, while South Island robin (
Petroica australis), tomtit (
P. macrocephala) and rifleman (
Acanthisitta chloris) populations showed little or no change, and grey warblers (
Gerygone igata) significantly decreased. All species showed a greater increase during the first 4 years of the survey compared to the second 4 years, which suggests that meso-predator release of rats may have occurred from ~4 years after the start of the surveys. The presence-absence technique is simpler to conduct than the more commonly used 5-minute bird count method, and thus may be better suited for use by the community sector in similar situations.