Marine Snails Have Unique Swimming Patterns, New Study

A snail in a rain shower. Photograph: Henning Kaiser/AFP/Getty Images
A snail in a rain shower. Photograph: Henning Kaiser/AFP/Getty Images
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Marine Snails Have Unique Swimming Patterns, New Study

A snail in a rain shower. Photograph: Henning Kaiser/AFP/Getty Images
A snail in a rain shower. Photograph: Henning Kaiser/AFP/Getty Images

In the world's oceans, billions of tiny marine snails commute daily between surface waters, where they feed at night, to depths of several hundred meters during the day to rest.

Marine snails play an important role in geochemical cycles and climate: 12-13% of the global carbonate flux occurs when the calcium carbonate shells of dead snails sink to the depths, where they dissolve and contribute to atmospheric carbon and ocean acidification. But because they are difficult to study and can't be kept in the laboratory, the behavior of these animals is poorly known, especially for the subtropical and tropical regions where their diversity is greatest.

According to a study published Monday in the Frontiers in Marine Science journal, a US team led by researchers at the University of South Florida tried to address this lack of information. They filmed the movements of tropical marine snails and analyzed these both from a fluid physics and ecological perspective. They showed that each species has a distinct style of swimming and sinking depending on the shape of their shell (coiled, elongated, or round), and body size.

Between 2017 and 2019, the researchers caught multiple individuals of nine species of marine snails and transported them to the laboratory, where they recorded their behavior in a salt-water aquarium with a high-speed technique that tracks movement in 3-D with a pair of cameras. For each species, they calculated the absolute and normalized speed (relative to body length) during active swimming and passive sinking, the frequency of wing movement, the angle of descent during sinking, the tortuosity of the path of ascent during swimming, and the shells number.

The researchers found that each species has a distinct swimming pattern. Tiny snails with coiled shells swim more slowly whereas larger snails with bottle-shaped or wing-shaped shells swim faster because their larger sizes allow them to overcome the effects of water viscosity.

In a report published by the Frontiers in Marine Science journal, author Dr. David Murphy, assistant professor at the Department of Mechanical Engineering of the University of South Florida, said: "Understanding the swimming ability of these animals is helping us better understand their ecological importance and distribution in the ocean. Further, we hope to learn from the swimming style of these organisms to design a new generation of bio-inspired underwater vehicles."



Escaped Otter is Home Safe but US Zoo Says her Pal is Still on the Loose

  The two North American river otters escaped two weeks ago from the NEW Zoo & Adventure Park in Green Bay, Wisconsin. Reuters
The two North American river otters escaped two weeks ago from the NEW Zoo & Adventure Park in Green Bay, Wisconsin. Reuters
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Escaped Otter is Home Safe but US Zoo Says her Pal is Still on the Loose

  The two North American river otters escaped two weeks ago from the NEW Zoo & Adventure Park in Green Bay, Wisconsin. Reuters
The two North American river otters escaped two weeks ago from the NEW Zoo & Adventure Park in Green Bay, Wisconsin. Reuters

Ophelia the escaped zoo otter is back home but Louie remains elusive — perhaps in search of a mate.
The two North American river otters escaped two weeks ago from the NEW Zoo & Adventure Park in Green Bay, Wisconsin. Ophelia was captured Friday night, the zoo said in a Facebook post.
Her return was kept under wraps until Tuesday while she was held for observation. A veterinarian’s examination Monday cleared her for return to her enclosure, The Associated Press reported.
However, she “may not always be visible to guests,” the zoo said. “Ophelia has always been a bit shy and enjoys tucking into things to take naps throughout the day.”
The mammals escaped through a hole in a fence during a snowstorm.
Louie remains on the lam. “This is otter breeding season and we expect that, as a male otter, Louie is likely ranging a bit further from home than Ophelia did.”
It's unlikely Louie is too far away, the zoo said. Otters are territorial creatures.
He's undoubtedly safe — otters are native to the area — and poses no harm to humans.
The zoo has had help from a tracker, motion-activated cameras and reports from residents who see the critters, particularly those who are able to take photos or video of the animal.