Monitoring of long-tailed bats in the Iris Burn Valley, Fiordland 2017
A 2017 report on the results of monitoring a population of critically endangered long-tailed bats that were discovered in the Iris Burn Valley in 2011.

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Long-tailed bat monitoring report, Iris Burn Valley, Fiordland (PDF, 921K)

Summary

A population of critically endangered long tailed bats (Chalinolobus tuberculatus) was discovered in the Iris Burn Valley in 2011. Roost emergence counts were initially used in 2011 and 2012 to determine the status of the population. This evolved into roost catches banding individuals which have been conducted yearly since 2013.

Rodent control was initiated in 2014, with ground control and two aerial 1080 operations in 2014 and 2016. The outcome target of the pest control is to detect a stable or increasing trend in adult female survival/population size, and no declines relating to pest numbers, using minimum number alive (MNA) of adult females.

Females are best to monitor as they make up the majority of bats in a communal roost, males spend a lot of time in solitary roosts. Monitoring shows the population of female bats in the Rocky Point colony is increasing steadily and has doubled in size since 2014 and now has a MNA of 65 females.