Beetles are touring Australia—not the Fab Four, but the iconic Christmas beetle—and ’tis the season to start counting. The historic Christmas Beetle Count is underway and so far, 7,200 people have reported sightings across Australia (we’ve never actually tallied them until we noticed they were gone).
An official count using citizen science was started three years ago by Invertebrates Australia, an environmental charity founded by scientists. The Christmas beetle’s rise or fall, however, is still too early to call because there is no baseline data to compare.
Canberra is fortunate to have the CSIRO’s Australian National Insect Collection for reference, which holds 7,000 specimens of Christmas beetles (Anoplognathus).
CSIRO entomologist James Bickerstaff has his work cut out for him (Australia has about 400,000 species of insects that have yet to be named) but he still finds time to volunteer for the Christmas Beetle Count.
“People don’t even need to be aware that the Christmas Beetle Count is running, they just have to take photos of Christmas beetles and just by tagging it as a Christmas beetle on iNaturalist, it’ll get flagged in the project,” Dr Bickerstaff said. “It will be automatically absorbed into the count and be identified by the experts on the team.
“It’s hard to say whether they’re increasing or decreasing because we’ve only been doing this for three years now so it’s really hard to disentangle historic trends from what we’re seeing today. We don’t have a good historical record of Christmas beetles.”
There are 42 different species of Christmas beetles in Australia according to Dr Bickerstaff, who can identify every single one of them by the hairs on their bum (not the scientific terminology).
“You can quite easily tell species apart by looking at those hairs on the back end and they’ve also got different mouths and faces as well, which you can easily tell the species apart,” Dr Bickerstaff said. “You can also tell them apart from colouration and the size of the beetle.”
Canberra is home to 14 species of Christmas beetles, including the local duck-billed beetle (A. montanus) and if you look closely, it actually does look like it has a duck bill. Another local festive beetle is the washerwoman (A. porosus).
As a child of the ‘70s, I can recall when Christmas beetles were in plague proportions (perhaps exaggerated by my nostalgia for the good old days) but there were definitely more beetles 50 years ago than the rare few we see today, despite a lack of scientific data.
“It’s really hard to try and figure out when they declined and how much they have declined by,” Dr Bickerstaff said. “It is very difficult because we don’t have that baseline data.”
So the jury’s still out, with Invertebrates Australia stating on their website: “we cannot conclusively say if there’s been a decline.”
So come on Professor Ken Behrens, stop taking selfies, start photographing Christmas beetles and post and tag them on iNaturalist.
Some citizen scientists have already submitted photos of four very rare species last sighted decades ago. For one species (A. vietor), observers took the first known picture of a living individual – it had previously been known only from a single, dead beetle. This record was 300km away from the only site previously known for this species.
We must be patient, however, because a few more years’ worth of data is needed before scientists can announce anything conclusive about Christmas beetle population trends.
To participate in the Christmas Beetle Count, visit invertebratesaustralia.org/christmas-beetles
