Main Club, 4 July 2025

Kelly Sheldrick shares fascinating discoveries from her ongoing research into WA’s microbat communities.

Kelly Sheldrick’s recent presentation on Southwest bat research opened many eyes to the remarkable diversity and conservation challenges facing our local microbat populations. Speaking to our naturalist group in July, Sheldrick outlined her comprehensive study across 14 trapping sites, revealing both encouraging discoveries and urgent conservation concerns.

Why Bats Matter

Sheldrick began by saying, “Why bats?” Because “they are awesome!” she declared, acknowledging that despite negative connotations, bats provide essential ecosystem services. These nocturnal mammals are master insect controllers, pollinators, seed dispersers, and their guano fertilises. Beyond ecological benefits, bat research has driven medical breakthroughs, technological advances, and even helped visually impaired people learn echolocation techniques.

With 42 species across Western Australia from seven families, bats represent one of our most diverse mammalian groups. Yet the Southwest’s bat fauna remains poorly understood, with only nine species documented in the region—often at low densities and with unresolved taxonomic questions suggesting possible cryptic species.

Regional Differences Revealed

Sheldrick’s research uncovered striking patterns between urban Perth and the southern forests. In Perth, two species dominate the catches: Gould’s Wattled Bat (Chalinolobus gouldii) and the Lesser Long-eared Bat (Nyctophilus geoffroyi). These urban-adapted species thrive in city environments, with Gould’s Wattled Bats readily occupying bat boxes and being well-documented on iNaturalist.

“What’s interesting is that Perth catches showed more males,” Sheldrick noted, “which could indicate sex segregation for some species.” Notably absent from Perth catches were Chocolate Wattled Bats (Chalinolobus morio), which prefer dark areas with habitat connectivity.

The southern regions tell a different story, supporting much higher diversity with more Southern Forest Bats (Vespadelus regulus) and a greater proportion of females.

The Southwest’s Endemic Species

Sheldrick highlighted the region’s high endemism, with several species occurring nowhere else in the world. Three species particularly captured the audience’s attention:

1. The Western False Pipistrelle (Falsistrellus mackenziei) presents a concerning conservation picture. “This species’ range is retracting,” Sheldrick explained. “It was once found in Perth, but now we rarely detect it north of Collie.” Climate change may be playing a role, making this a priority species for future research.
2. The South-western Free-tailed Bat (Ozimops kitcheneri) represents another Southwest endemic,
3. while the White-striped Free-tailed Bat (Austronomus australis) found across Australia stands out as the region’s largest microbat, with calls so low-frequency human ears can hear them—if you still have good hearing.

Research Methods

Sheldrick’s presentation highlighted innovative approaches to studying these elusive creatures. Her team of volunteers employed both traditional trapping methods using harp and mist nets, and acoustic monitoring technology. The Long-eared Bats (Nyctophilus species) proved particularly challenging, being acoustically indistinguishable and requiring physical capture for identification to species level.

They have been utilising acoustic lures—recordings of European bat social calls played near traps. “Lures increased capture rates by 4-8 times across all species,” Sheldrick reported. These recordings, captured outside maternity roosts, showed no evidence of causing distress to the bats.

The complementary nature of different survey methods became apparent. While acoustic surveys excel at detecting the loud, low-frequency calls of white-striped free-tailed bats, these fast, high-flying bats prove nearly impossible to trap. Conversely, the quiet long-eared species require trapping for proper identification and are less detectable in acoustic surveys.

Conservation Challenges Past and Present

Sheldrick’s research revealed sobering examples of habitat loss. Historical records show a maternity colony at Yanchep caves documented in 1924, but the site was subsequently mined for guano, and ongoing ground water extraction has led to drying of the caves, destroying this important habitat.

Today, similar threats persist. At Yalgoo, Sheldrick recently observed approximately 300 bats of two species using the gypsy tunnel near the carpark entrance—a significant maternity colony now threatened by a mining proposal. “We’re investigating how the value of ecotourism could save this roost,” Sheldrick explained, highlighting how conservationists are exploring alternative economic arguments for habitat protection.

Even established colonies face ongoing challenges. The Margaret River Chocolate Wattled Bats’ maternity colony, while protected in a cave system, experiences regular disruption from the adjacent carpark, illustrating the need for better management of critical habitats.

Future Research Priorities

Looking ahead, Sheldrick outlined several research priorities. The ongoing search for Chocolate Wattled Bat populations represents urgent work to understand this species before further habitat loss across its WA range. Climate change mitigation strategies for the declining Western Falsistrelle require immediate attention, though the species’ elusiveness makes research challenging.

Future work will focus on confirming species presence at additional sites while reducing disturbance to critical maternity colonies. Protecting roost sites has emerged as a key priority, particularly for “non-threatened” species that may be at risk but lack formal protection status.

Radio tracking studies planned for December promise exciting insights into habitat use patterns our southwest endemics, while ongoing surveys aim to fill knowledge gaps across the Southwest’s under-surveyed areas.

Opportunities for Citizen Scientists

Sheldrick’s presentation concluded with encouraging news for citizen scientists. The scale of the region and limited research resources mean community involvement is essential rather than merely welcome.

Regular bat box monitoring along the Canning River occurs monthly, providing consistent volunteer opportunities. The community science platform iNaturalist already hosts numerous records of Gould’s wattled bats, demonstrating how citizen observations contribute to understanding species distributions. The potential for expanding this to acoustic records is also possible.

Trapping surveys will resume in November, with optimal conditions occurring during this period. December’s radio tracking studies offer particularly exciting opportunities for volunteers to follow individual bats and understand their habitat use patterns.

Priority areas for citizen scientists include helping survey under-researched areas to improve understanding of species distributions. The Southwest still contains significant survey gaps, and citizen scientists can play a crucial role in filling these knowledge voids.

A Call to Action

Sheldrick’s presentation painted a picture of remarkable diversity facing unprecedented challenges. The Southwest’s bat fauna represents a unique evolutionary heritage shaped by millions of years of isolation. These species have survived ice ages and dramatic climate shifts, but now face threats from habitat loss, climate change, and human disturbance.

The research demonstrates that citizen scientists can make genuine contributions to bat conservation. Whether through regular monitoring, participating in surveys, or recording observations on iNaturalist, community involvement multiplies researchers’ capacity to understand and protect these remarkable animals.

As we face the potential loss of sites like the Yalgoo colony, the urgency becomes clear. Every observation, every monitoring session, and every voice raised for habitat protection contribute to ensuring future generations can experience the wonder of watching bats emerge at dusk from their roosts.

The Southwest’s bats have evolved in isolation for millions of years. Whether they survive the next century depends on how effectively we can combine scientific research with community action. As Sheldrick concluded, “The opportunities are there—the question is whether we’ll seize them.”

Ry Beaver

For more information about participating in bat research, look for the WA Bat Network on Facebook or information on the CCWA website. Trapping surveys resume in November, with radio tracking opportunities available in December.