Survey of bats on the south coast and ranges of the Shoalhaven region in New South Wales

Abstract

Surveys for echolocating bats were conducted primarily by harp trapping and echolocation detection in the Shoalhaven region on the south coast region of New South Wales from 1989 to 2021. A total of 399 sites were surveyed by harp trapping and 175 sites through echolocation call detection. Mist nets were used to catch bats at one site in 1989. The survey covered a range of vegetation communities at altitudes that ranged from near sea level to 770m asl. One hundred and seventy-four harp trap sites were within conservation reserves/state forests and the rest were on freehold land. Each site was trapped from 1 - 4 nights for a total of 666 harp trap nights. Sites surveyed electronically were sampled between 1-2 nights for a total of 230 samples of either 30 minutes duration or an entire night. A total of 18 species were captured in harp traps during the survey. The Yellow-bellied Sheath-tailed Bat Saccolaimus flaviventris was observed once during spotlight surveys and detected electronically. The White-striped Free-tailed Bat Austronomus australis was heard echolocating at night and detected electronically. The Little Bent-wing Bat Miniopterus australis was only detected electronically. The highest capture rate was in Jerrawangala National Park where 38 animals consisting of five species were trapped in one trap on a single night. The highest species richness and density was found in tall open forests, especially those along the Illawarra escarpment. Analysis of abundances found that the Little Forest Bat Vespadelus vulturnus was the most common species accounting for 45% of animals trapped. Seven species currently listed under the Biodiversity Conservation Act (2016) were caught and another detected electronically. Those trapped were the Large-eared Pied Bat Chalinolobus dwyeri, Eastern Falsistrelle Falsistrellus tasmaniensis, Golden-tipped Bat Phoniscus papuensis, Eastern Bent-wing Bat Miniopterus orianae oceanensis, Eastern Coastal Free-tailed Bat Micronomus norfolkensis, Large-footed Myotis Myotis macropus and Greater Broad-nosed Bat Scoteanax rueppellii. In addition, the regionally rare Ride’s Free-tailed Bat Ozimops ridei was trapped. The survey provided the first live specimens of Eastern Forest Bat V. pumilus in the south coast region, a range extension of some 260km south of the previous accepted records in the Watagan Mountains. The capture of a Large-eared Pied Bat at Meroo NP represents a southern range extension for this species. Morphometric data are presented plus comments on species habitat preference.