20/06/2026
❤️ Rockpool finds ❤️
Sea squirts are some of the strangest animals in NZ rock pools. Even though they look like plants, slime, or eggs, they are actually marine invertebrate animals called tunicates or ascidians.
Interesting facts:
* They are close relatives of vertebrates
Their larvae briefly develop a primitive spinal cord, making them surprisingly related to humans compared with many other marine creatures.
* They are filter feeders
They continuously pump seawater through their bodies and filter out microscopic food particles.
* The “squirt” name is literal
If disturbed underwater, many species eject jets of water from their siphons.
* NZ has both solitary and colonial species
Some live alone like soft sacs attached to rocks, while others form huge colorful colonies like the yellow one you found.
* They help clean the water
By filtering seawater, they play an important ecological role in coastal ecosystems.
* They thrive in shaded wet places
You’ll often find them under rocks, in crevices, wharf pilings, caves, and tidal pools.
* Some are invasive
A few non-native tunicate species have become pests in marinas and aquaculture areas in NZ because they spread rapidly over surfaces.
* Their colors can be wild
Bright yellow, orange, purple, red, translucent white, and even fluorescent-looking species exist.
Common places to spot them
* East coast Auckland rock pools
* Raglan intertidal areas
* wharves and marinas
* mussel-covered reefs
* shaded volcanic rocks
They’re one of those creatures people walk past without noticing — until you look closely and realize the rocks are covered in tiny living filter-feeding animals
