Hunting Invasives


After studying invasives in class, students at Wentworth College went to Red Beach on the Whangaparaoa Peninsula. There they found an abundance of the Mediterranean fan worm. These worms live in a hard tube which is grown by the worm, and is easily identified by the orange filaments which form a fan when opened from the top of the tube. This species is registered as an invasive globally, and spreads easily as they can grow on any solid substrate which leads to them getting carried around the ocean on the bottom of boats and ships. Once it gets to a new place, this species can establish quickly, as one female can produce 50000 eggs during breeding season!

Upon finding an abundance of this species at Red Beach, the students wondered what they can do to try reduce the number of worms on their shore. However, when threatened this species will release it’s gametes as a form self-preservation. This means that if you spot this species on your local beach, it is best to leave them as they are and report your finding to your local council or MPI by phoning 0800 80 99 66.

Invasive Fanworm

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