By Nina Mercer, Planning and Performance Advisor
Crawling around in the dirt on the forest floor isn’t something I’ve done a lot of, but that’s because I’ve never snailed before! And snailing must be one of the more rewarding pieces of conservation work I’ve done in a long time.
What is snailing?
Essentially snailing is surveying sites for our native Powelliphanta snail. It’s a little-known fact that the lower North Island has several reserves that are home to these giant snails, and the species we were looking for was Powelliphanta traversi latizona.
Fascinating facts about Powelliphanta
There are about 20 species of Powelliphanta across Aotearoa New Zealand, and they’re among the largest snails in the world. Found in wet native forest habitat, and some species in alpine tussock, these amazing creatures are carnivores, slurping up a worm the way we slurp up spaghetti bolognaise! (Check out this video here).
Protecting Powelliphanta
Intensive rat and possum control is undertaken at the reserve we were monitoring, rats are the number one predator of snails, but they are also susceptible to possums in some locations, pig foraging, hedgehogs and the song thrush. Our survey results will give an indication of how well pest control in the reserve is impacting the snail population.
Our mission for the day
Under the expert guidance of Biodiversity Ranger Aimee Stubbs, our team of intrepid hunters hiked into a small inland scenic reserve. We had three survey plots on our radar and quickly found the first. After taping off the 10 x 10m plot and creating an A, B, C, D grid it was time to get on our knees and start snailing!
Working as a team
There isn’t a lot of finesse to snailing, we lined up in a row along the tape measure and shuffled forward on our knees. Butts in the air and eyes to the ground we scooped and sifted leaf litter as we crawled, carefully replacing the litter to keep the snail’s home nice and moist. The shout of ‘I’ve got one’ elicited excitement and a little envy, I had to remind myself that it’s not a competition.
Empty shells were also found in the search; and deposited into the ‘bag of death’ to be sent off for analysis.
My first snail
Finally, I found my first snail, and it was a big one! With a gleeful shout I made sure everyone knew of my discovery and put the marker in the ground to come back and measure the snail. A bonus with snail monitoring is that you can mark the spot you find them knowing they will still be there when you come back to measure and record!
An amazing haul
With 14 snails found in the first plot, we moved on to the second and found 48! We barely had enough stakes to keep up with the finds, so exciting. And one of my snails was the biggest at 52mm across! (Again, not a competition Nina). The third plot was host to 16 snails so all up we found 78 snails; our long-term recovery goal is to find more than 12 snails per 100m2, so we’re tracking far above average so far! Ranger Aimee was very happy!
Tired but triumphant
Somewhat weary from all the crawling and the odd clamber over and under logs, we wandered back to the cars feeling pleased with the day. It’s exciting to see first-hand how the mahi we are doing is making a difference for our taonga species.
Snailed it!
Authors note – Snailing is not the technical term for this mahi, but we like the sound of it 😊
