by Jess Cartwright
The story of the Christmas Island Pipistrelle sounds like it should have a happy ending, but this species upsettingly became extinct in 2009. The factors that contributed to its decline are vital to understand how other bat species can be conserved. Earth has been home to bats for more than 50 million years and there are over 1400 species, globally. Each bat is vital to our ecosystem and in need of our protection. If we can learn anything from the Christmas Island bat, it’s what else needs to be done to ensure other species don’t decline to extinction. We need bats to increase in numbers and thrive.
The Christmas Island bat lived on and was native to Christmas Island, Australia. It was an incredible vesper bat; small in size (3-4.5g) with brown fur with yellowish tips and rounded triangular ears. It had a distinct call that could be detected through echolocation and were the only microbats on Christmas Island. They fed off a diet of insects, foraging above and below the canopy, and made their roosts in tree hollows and amongst forest vegetation.
What’s strange about this bat’s extinction is that it is so well documented. It used to be sighted on the island regularly but declined rapidly from 1994. In 2006, a well-known communal roost was assessed which housed 54 bats, and similar other roosts were found on the island. Just three years later, in January 2009, this roost only had 4 roosting bats. An effort was made to place these bats in captivity to preserve the species but on reassessment in August of the same year, only one bat was detected leaving the roost. It has apparently never returned. The opening page of John Woinarski’s book, A Bat’s End: The Christmas Island Pipistrelle and Extinction in Australia has a harrowing account of the final days that scientists spent frantically trying so save the species:
‘The scientists set up an elaborate maze of netting to try to catch it. It is a forlorn and futile exercise, for, even if captured, there is little future in one bat. But the bat evades the trap easily, and continues foraging. It is the evening of 26 August, humid under the dense rainforest. The last bat emerges from its day-time shelter, and the bat detectors signal its movement to the scientists. It flies to and fro along its regular foraging beat for several hours. The detector blips frequently; then less; and then no more. The bat is not recorded again that night, and not at all the next night. The bat is never again recorded. The scientists search all nearby areas desperately over the following nights, and across the island. It has gone. There are no more bats. Its corpse is not, will never be, found. It is the silent, unobtrusive death of the last individual. It is extinction.’
It is not conclusive what forced the bats into extinction, but there are a number of suspected reasons that contributed to the sharp decline in numbers. These include disruption from other introduced animals; wolf snakes, yellow crazy ants, feral cats, black rat and giant centipedes have all been identified as a potential threat. Unknown illness or disease, disturbance of the bats’ roosts and climate change have been other topics of interest. It is fair to assume that if research and interference had been conducted earlier, the extinction of this bat might have been avoided.
So what will help bat conservation? Firstly, bats have a pretty bad reputation thanks to the media and fear from the general public. This reputation is mostly unfounded and needs to be overcome. People are often scared that bats are rabies-ridden, and while it is very possible to carry the disease, bats are not really at any higher risk than other mammals. Wearing gloves while handling bats and having up-to-date rabies jabs all but eliminates a possible transition to humans. They are also not seen as typically ‘cute’, and therefore aren’t viewed favourably; although, with those big ears and tiny claws how can you not find them adorable? Bats have also been labelled as a ‘pest.’ Because of their protected status it means developers often have to legally conduct bat surveys before any work can be done, which can sometimes result in delays and increased costs.
These misconceptions and bad press often detract from the fact that bats are SO integral to the environment and absolutely need to be protected. Not only do they help with pest control (are you going to start eating flies and insects?) but they also pollinate flowers and spread seeds. They are often seen as an ‘indicator species’ because changes to bat populations can highlight a change to biodiversity in a particular area.
There is still so much we don’t know about bats; they cannot be tracked all of the time, roosts often change and they cannot be tagged easily, or as humanely, as other animals. A lot of research on bats is completed by ecologists and volunteer groups, who have a real passion for conserving animals. But we also need your help – you could be one of the lucky ones and have a roost concealed in your home! We rely on the kindness of the public to allow volunteers to survey roosts on private property, even one survey a year can have a huge impact. We need a combined effort to help these little animals and to save more species from extinction.
How you can help:
If you find an injured bat, or suspect bat activity in your home or a nearby building, please call your local rescue centre who can advise what to do.
Do not use flypaper in your home and be aware if you have a cat - a lot of bats are injured or killed due to being hunted by cats. If you suspect a cat-attack, please call for help from an experienced bat carer such as those at Severn Wildlife Rescue. Even if an injury isn’t obvious, there could be some internal damage or infection passed on from the cat.
Do not move or handle bats unless specifically asked to by a trained bat carer or handler.
If you have building work done on your house, or with your work, make sure the legal steps are followed and bat surveys are conducted to ensure bat safety.
If you want to, setting up a bat box in your garden could offer bats a place to call home throughout the year. Just make sure you don’t disturb the box once it’s in place.
If you are in a position to, if you remove a natural habitat (trees, ponds, hedgerows etc) try and replace them. If there’s a new development in your area, hold them accountable to ensure there are enough natural spaces to accommodate the wildlife they are disrupting.
If we all work together, we can help ensure bats can continue to live in our changing world.
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