Shedding Light On The Secret Lives of Microbats in Perth

A collage of microbat images, both flying and close-ups

It is common to see bats flying around streetlights on most nights – Their dark silhouette and mid-air antics. They are so fast, they are often hard to identify. Come to think of it, if we knew they were bats we would fly inside just as quickly!

Our fear of bats is quite irrational. It stems from how bats are depicted as monsters in popular culture and folklore. Their dramatic features with fanged teeth and unusually large ears, don’t help their case. In fact, it is these features that have inspired countless stories of bloodsucking vampires and their legions, and one very horrific tale of Count Dracula who lurks in the dark to stalk and prey upon his unsuspecting victims.

In truth, very little is known of our winged insect-eating critters. They are shy and inconspicuous. They are nocturnal creatures, who spend most of their active time hunting for insects and foraging food. And their curious habits remain shielded by the copious cover of the night when they operate and their ability to quickly disperse at the first sign of intrusion.

We do, however, know that they are an indispensable part of our environment. They are insectivores that help curb the spread of agricultural pests. And they contribute immensely to biodiversity.

Here in this blog, we shed light on the secret lives of microbats in Perth. Their habits and habitats. And what we must do to protect the threatened creatures.

 

Flying Mammals

Bats make up almost one-quarter of all known mammal species in the world. There are two varieties of bats – the megabat, also known as the fruit bat, and the microbat.

  • Megabats can be large and weigh up to a kilo. They have large wingspans of over a metre.
  • Microbats, on the other hand, are tiny. Some microbats weigh a mere 3gms and can fit through small gaps that are 5mm wide. The larger microbats can weigh up to 150gms and have wingspans of 25cms.

Scientists believe that the two varieties of bat evolved separately and regard them as distinctly different groups.

Microbats give birth to one pup per year, or sometimes twins. The babies are born during spring or summer, when days are warm with ample sunlight and when there is a good supply of food. They are born with their eyes closed, but within a short span of 6-8 weeks, they develop into fully grown adults that can fly and feed independently.

 

Echolocation On

Microbats are extremely adept flyers and can remain airborne for hours at a time. They use echolocation to navigate and hunt in the dark. Bats emit high-frequency sound waves that bounce off objects. By reading the returning waves they are able to tell what lies in their path. The microbats can locate flying insects and detect obstacles in their way with great accuracy using this method.

The waves that bounce back to the microbat tell it a lot about the object – how far it is, its texture, its shape, its size and if it is stationary or moving.

Many bats have special features to help them echolocate. Some have very long ears for hearing. Others have a growth on their nose, called a nose leaf, which focusses sound.

The Myotis microbat that lives near waterways has been recorded catching over 1200 flies in under 1 hour.

 

Gleaning Off

Microbats use this technique of “gleaning off” to catch insects that are not flying.

Bats do this by flying slowly, hanging on branches or even hovering closely. The microbats listen for tell-tale sounds of movements that their targets make like the motion of bugs on the ground or as insects shuffle along branches. They use a combination of echolocation and instinct to zero in on their prey. Then they strike and pluck the insects off the leaves, branches or ground, wherever they may be. In a clean hit.

The Golden-tipped microbat uses this technique to glean off spiders, swooping them straight out of their webs.

 

Torpor Mode

Microbats go into a state of torpor, which is very similar to hibernation, to conserve energy on days when food is scarce. Torpor can only be used temporarily for a few hours or days at a time.

The microbats mostly eat insects. One Australian species, called the ghost bat, is also known to eat small birds, frogs, lizards and other smaller bats.

 

City Living

During daylight hours microbats are known to spend their time inside hollows of tree trunks or branches. The clearing away of trees is creating a major lack of habitat for our vulnerable critters.

In such conditions, microbats will find shelter in manmade structures such as inside mineshafts, tunnels, buildings, under bridges, inside rooftops and in your gardens.

Usually, microbats are extremely fussy while choosing their roosts. You can help microbats by installing safely designed and comfortable bat boxes.

Clear away debris or branches from their flight path. Remove barbed wires from around your property. Ensure that the bat box you install is placed high and in direct sunlight – the best position is facing East in direct sun half-day and shade in the other half. Inspect the box regularly. And, report feral bee infestation immediately.

The Yellow-bellied Sheathtail microbat has an echolocation call that people with sharp ears can hear – a metallic sounding tick tick tick.

 

Bat Haven At The Wetlands Centre

We, The Wetlands Centre Cockburn, are located in the heart of the Beeliar Regional Park, surrounded by abundant natural beauty. Here we have been working at rehabilitating & conserving our wetlands and educating our community on wetland concerns for the last 25 years.

It is our dream to create safe habitats for all our wildlife, including our microbats. Together with bat expert and specialist Joe Tonga, we have installed a number of well-designed bat boxes towards this endeavour. Our bat boxes showcase healthy bat roosts that are thriving!

Our bat stalk night for children is an adventurous outdoor activity, where we learn about bats through real-life encounters. Children love flashing their torchlights and being out in the bush, and it is, of course, all under guided supervision. We also conduct the bat stalk night for adults with nibbles – cheese and drink – and deep conversation.

Ask us about our bat programs. Take a look at our many bat boxes. And learn more about these beautiful wetland creatures – the microbats!

This article includes insights from GoBatty.com.au, a blog run by Joe Tonga of Natsync Environmental, our local bat expert.

A Wetland Habitat For Our Amazing Turtles

A close-up shot of an oblong turtle with an inset of one swimming in the wetlands

Turtles are remarkable and resilient creatures that inhabit our wonderous wetland worlds. They are widely celebrated in both popular culture and folklore as totems of balance, beauty and prosperity. In Aboriginal culture too, turtles are seen as symbols of longevity, endurance, and the continuation of life (especially in the face of great hardship and struggle).

We have much to learn from our endearing turtles. However, the avenues are limited as turtles are also inherently shy creatures. They seldom venture out, staying confined to the comfort of their wetland habitat and sanctuary for long stretches of time. And their rituals of mating, nesting, feeding and living, remain largely undocumented and mysterious.

Hidden in the grassy underbrush and marshy swamps, they thrive. Feeding on bugs, snails, worms, fish, crustaceans, plants and animals, scavenging and flourishing, they play a crucial role in the wetland ecosystem. They are vital indicators of wetland health. This is why their ever-dwindling numbers, impacted habitats and disrupted food-webs demand our most serious consideration.

 

Come, Meet Our Oblong Turtle

The oblong turtle or, the long-necked turtle, is a native species that is only found in this part of the world – in a small pocket at the southwestern tip of the state of Western Australia. And we are fortunate for their presence here!

The oblong turtles owe their name to the oblong shape of their carapace (upper shell) and snake-like long neck. Dark brown or muddy black in colour, these turtles are found in waterways across Perth and throughout the south-west. They occur in permanent and seasonal freshwater habitats, including rivers, swamps, lakes, damp lands, and natural as well as artificial wetlands.

Adult turtles can grow large and measure about 30-50cms from the tip of their tails to the end of their beaks. The young hatchlings are tiny as they begin their journey though, with a carapace merely the size of a 20-cent coin!

A long neck turtle walking through the wetlands
Image by Sharon Mcarthur

The Turtle Nesting Period is On!

September to January is a special season indeed. At this time of year, you can witness turtles leaving their watery homes in search of suitable nesting sites. They are known to travel up to a kilometre in search of the perfect site with soft sandy soils where they can lay their leathery eggs.

Unfortunately, a turtle out of water is a turtle at risk! Turtles get run-over by cars as they cross busy roads and pavements, oftentimes distracted by loud sounds and noise from moving traffic. Turtles are also exposed to birds and other predators that prey on them as they find their way. Dehydration and tiredness from the long journey and the added confusion of a changed or disturbed site can cause the turtle to feel lost and ultimately perish from fatigue.

If you are lucky to site a turtle that is on its way, help it cross the road by halting incoming traffic till it crosses. If this is too risky, you could lift it across the road (make sure that you take it in the direction it is headed and not back!) and ensure that there are no other threats around. If you have the time, you could also follow the turtle (at a safe distance) to and from the nesting site. Protecting our exposed and vulnerable turtles can go a long way in ensuring the survival of the species.

 

Threats to The Oblong Turtle

We lose a number of turtles to road accidents each year. In fact, in the period leading from September to January when turtles nest, and from June to July when hatchlings make their way back home to the wetlands, our turtles are at their most vulnerable.

A baby oblong turtle peeks above the water surface to breathe.Feral animals including birds of prey, cats, dogs and foxes are a significant threat to our oblong turtles. Feral animals are known to attack the turtles as well as their nests, feeding on eggs. Poaching and removing turtles from their wild habitat to keep as domestic pets is also a major threat. Although catching and keeping turtles as pets is illegal and punishable by law, it still happens.

And finally, it is the increasing urban sprawl, especially in the vicinity of the wetlands, that is leading to fewer and more disjointed habitats for our turtles. The compromised water quality and enhanced pollution levels are impacting their numbers, even as safe and suitable habitats become threateningly scarce.

 

Turtles on Your Property?

If your home happens to be popular with the turtles and you see a great number on your property, chances are that you are on a nesting site! Turtles are known to follow the same pattern year-on-year and are likely to end up in the same favourite spot for nesting. If you are a turtle buff, this can be an incredible opportunity for you to witness something magical!

Allow the turtle to nest and observe at a safe distance. Ensure that your pets are on a leash and away from the turtle. Make sure that there are no other threats that could harm the turtle. The female turtle will take anywhere between 15-30 mins to lay her leathery eggs, using her plastron (lower shell) and legs to dig and later cover-up the hole.

The turtle will be tired from her strenuous journey and vigorous nesting activity. If you find her at risk, you could help her get back to the wetlands safely, but not unless you are sure that’s the direction she is headed in. Keep the nest undisturbed while the mum is away. Turtle hatchlings will emerge after a period of incubation, and you can help them get back to the water too.

Here are some handy instructions if you are required to move a nesting site or handle a turtle anytime. Please remember that our turtles are wild creatures, and it is not encouraged to interfere with their movement unless they are at risk. That is please do not pick up hatchlings or adults unless absolutely necessary!

An illustration showing the right way to hold a long neck turtle.

Handling a Turtle: When handling a turtle prepare for them to resist and squirm strongly. They do not bite; however, they are known to scratch and struggle. Take care to keep a strong hold and not to drop them when this happens. Wrapping a small damp towel around the turtle can help you get a good grip. Always use both your hands and keep the turtle away from your own body.

Moving a Nest: If you are required to move a nest for any reason, or if you come across a compromised nest and want to help relocate it, here is what you do: Make sure you dig around with gentle hands and get all the eggs in the nest. Mark the position the eggs were in exactly and ensure you put them into the relocated site as they were found. The fresh hole you dig should be at the same depth and with similar conditions of dampness or dryness. Remember turtle eggs that are rotated will not hatch! If the temperatures are too cold too, the eggs won’t hatch!

 

Facts You May Not Know About Our Turtles

Here are some quick oblong turtle facts that may surprise and wow you!

  1. Freshwater turtles, such as our oblong turtles, can drop their body temperature, slow their pulse rate and use their stored body fat in place of fresh food to survive severe hot and dry conditions. This ability, known as aestivation, is the reason our hardy turtles can cope with the roughest Western Australian weather.
  2. Turtles are the only creatures with an exterior shell that is all bone and attached to their spine. The turtle shell is living material, much like our own fingernails. And they can sense pain, touch and temperature through it!
  3. It is a common misconception that our oblong turtles can protect themselves by retracting into their shells. Oblong turtles cannot retract into their shell!
  4. Our oblong turtles can live a long life of over 60 years when the conditions are right. They need to live long because they have very low recruitment rates (few surviving offsprings). In fact, on average only 1% of turtle eggs go on to hatch and survive until adulthood.
  5. Turtles are known to feed on the dead and decaying organic matter and debris. Turtles help keep the waterways clean and aid in wetland function.

 

Help Us Turtle Watch!

Sighting a turtle is a beautiful and moving experience! Be sure to share your lucky sighting at climatewatch.org.au. You can log your sighting using their app. Or call us at The Wetlands Centre Cockburn at our Turtle Watch Helpline.

Keeping a lookout on the migration patterns and movements of our native turtles helps us identify important habitats and nesting grounds. It also helps us create safer homes for these amazing wetland creatures!