Non-native Japanese skeleton shrimp, orange sheath tunicate and American slipper limpet all found at the Port of Ipswich.
An insight into the creatures that inhabit the water around Suffolk's county town was given in a recent presentation by George Seinet, environmental coordinator for Associated British Ports, which operates the Port of Ipswich.
Species non-native to the UK Mr Seinet has seen include the American slipper limpet - "They can stick to everything and block up outflows on boats," he said.
Less troublesome are the orange sheath tunicate, a tube-like invertebrate which siphons seawater through its body for food, and the Japanese skeleton shrimp, which Mr Seinet has also found.
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"I record them, take pictures and send details to the NNSS (non-native species secretariat)," continued Mr Seinet, who says warmer temperatures caused by climate change is one reason why species originating from outside the UK are venturing into Suffolk waters. Non-natives also arrive attached to boats, which have travelled from foreign waters, he said.
Non-native pacific oysters have also been seen at the Port of Ipswich although they get short thrift from Mr Seinet. "I go round at low tide and bash them with a hammer," he continued.
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Mr Seinet was speaking at the recent Stour & Orwell Forum held at the Royal Harwich Yacht Club in Woolverstone.
When asked during the Q&A session what species he most dreaded finding lurking beneath the surface of the port's water, Mr Seinet named, without hesitation, the carpet sea squirt.
According to the NNSS, this filter feeding marine invertebrate was first identified in UK waters in 2008.
It forms into large colonies, carpetting hard structures on which it grows and has already caused havoc in other countries such as New Zealand and the USA.
"It literally smothers everything, even mussels and crabs, and the costs of getting rid of it are phenomenal," added Mr Seinet
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