For the first time, footage has been recorded of the rare carnivorous New Zealand snail, Powelliphanta augusta, laying a small white egg from an opening beneath its head, resembling a small chicken egg. The moment was documented during a routine weight check at a facility on the West Coast of New Zealand's South Island, where conservation rangers have cared for Powelliphanta augusta snails housed in chilled containers for nearly two decades to save the species from extinction.
The video shows a small white egg starting to emerge from a Powelliphanta augusta snail's neck. Conservation officers state that they have never observed this behavior before.
Lisa Flanagan, who has worked with Powelliphanta augusta snails for 12 years at the Department of Conservation, expressed her surprise at the event. "It's remarkable that in all the time we've spent caring for the snails, this is the first time we've seen one lay an egg," she said, according to the Associated Press. "They're polar opposites to the pest garden snail we introduced to New Zealand, which is like a weed, with thousands of offspring each year and a short life."
Powelliphanta snails are some of the world's largest snails, roughly the size of a golf ball, and are found only in New Zealand. These carnivorous snails feed mainly on slugs and earthworms, which they slurp up like spaghetti. They have large, distinctive shells in a range of rich earth colors and swirling patterns.
Powelliphanta snails have a genital aperture on the neck, which allows them to remain in their shell during mating and egg-laying. The snail uses a genital pore located on the right side of its body, just below its head, to simultaneously exchange sperm with another snail. The sperm exchanged between Powelliphanta augusta snails is stored until each snail creates an egg.
הצגת פוסט זה באינסטגרם
Each Powelliphanta augusta snail takes eight years to reach sexual maturity and has a long but slow reproductive life. After reaching sexual maturity, each snail lays about five eggs annually, shaped like a hen's egg, and it can take more than a year for the eggs to hatch. Some of the captive snails are thought to be between 25 and 35 years old.
In the early 2000s, the Powelliphanta augusta snail was the center of public uproar and legal proceedings when an energy company's plans to mine for coal threatened to destroy its habitat. As a result of public discontent and legal proceedings, about 4,000 Powelliphanta augusta snails were removed from the mining site and relocated to new places to conserve this slow-breeding species. Approximately 2,000 more snails were housed in chilled storage in the West Coast town of Hokitika to ensure the preservation of the species.
The conditions in the containers mimic the alpine climate of a remote mountain, which was the snails' former habitat, destroyed by mining activities on the South Island's West Coast. As of March this year, there were nearly 1,900 Powelliphanta augusta snails and nearly 2,200 eggs in captivity, according to the Department of Conservation.
Ingrid Gruner, the Department of Conservation's regional biodiversity liaison, described the footage of the egg-laying moment as "quite remarkable," according to The Guardian. "In all the years we've been doing that work, we've never encountered it," she added. "The species continues to surprise us."
Very little was known about Powelliphanta augusta snails before the Department of Conservation took them into captivity. The conservation program for these snails is likely to have saved the species from extinction, and it is now slowly recovering. New colonies of Powelliphanta augusta snails have been established in the wild but are being monitored to ensure they can form a sustainable population.
The former habitat of the Powelliphanta augusta snail was a remote mountain on the West Coast of the South Island that has been engulfed by mining since 2006 when Solid Energy began mining on the Mt Augustus ridge line near Westport.
Powelliphanta snails are hermaphroditic, allowing them to reproduce when encased in a hard shell. Other snails mate and lay eggs in a similar fashion, though some, like Norfolk Island's Campbell's keeled glass-snail, have been observed birthing live young.
The article was written with the assistance of a news analysis system.