What Is Sea Vomit, and How Can Scent Dogs Find It?

What is sea vomit?

Sea vomit is a nickname for carpet sea squirt, whose scientific name is Didemnum vexillum. It is a colonial tunicate: a marine animal whose individuals live together in a group. The colonies can form spreading covers on underwater surfaces. ²⁴

The nickname refers to the organism’s appearance; it is not a separate species. Other reported names include marine vomit and pancake batter tunicate. ⁴

Carpet sea squirt is considered invasive in several regions. An invasive species is one that spreads in a place where it is not native and causes harm. The sources say this sea squirt can smother native wildlife and threaten oyster farms and other aquaculture, or the farming of aquatic organisms. ¹²⁴

Why can carpet sea squirt cause harm?

Colonies can grow over marine life and surfaces. If growth is not controlled, it can smother and kill native species. The organism may also affect coastal businesses, including oyster farms. ¹²

It can occur around harbours, farms and marine equipment. Small pieces may cling to boat hulls, fishing gear or ropes, making them difficult to notice. The Herald reports that management can become difficult and costly once the species is widespread. ¹²

The supplied reports describe possible effects but do not estimate the total damage to wildlife or businesses. They also do not give a full account of how the species travels between places.

How does a scent dog find sea vomit?

Sgiath is a black Labrador who works with Dr Texa Sim, a marine ecologist based near Glencoe in the Scottish Highlands. Sim trained her to recognise the scent of carpet sea squirt. Before this work, Sgiath had training as a mountain rescue dog. ¹

The pair search coastal areas at low tide. Sgiath can indicate colonies and small fragments on items such as boat hulls, ropes and fishing gear. BBC reports that she has found hundreds of colonies. ¹²

The articles do not describe the precise training exercises or how each alert is checked. They report that Sgiath uses scent to draw her handler’s attention to places where the species may be present.

Does Sgiath remove the invasive sea squirt?

The reports describe Sgiath’s role as finding the organism, not removing it. Detecting a colony is separate from clearing it or stopping it from spreading. The supplied sources do not explain what happens at each site after a dog alerts to sea squirt. ¹²

A dog may help locate growth that people could miss, including small pieces on equipment. But the reports do not compare the dog’s performance with other search methods or measure whether using her leads to better control. ²

Why has Sgiath received an award?

The International Fund for Animal Welfare named Sgiath its Animal of the Year for her work detecting an invasive marine species. The award also brings attention to her handler’s conservation work. ¹²

BBC says Sgiath is believed to be the first dog in the UK trained to hunt sea squirts. The Herald says she is thought to be the first dog trained to detect this particular species worldwide. These are different claims, and both reports qualify them rather than presenting them as verified records. ¹²

The recognition highlights scent detection as one possible conservation tool. It does not establish how widely the approach can be used or whether it will control the spread of carpet sea squirt.