Triplefin fish


Triplefins are a small fish species which are found all over the world in many different colours. Though small, these fish are extremely important in the environment as they are an important prey species for many other marine organisms. Aotearoa is a hotspot for these tiny, finned friends with 26 species of triplefins which are only found here in New Zealand.

As a PhD student I have been using the spotted robust triplefin (Forsterygion capito) to understand the effect of plasticisers, the chemicals put in plastics, on the ability of these fish to reproduce. To do this, I exposed fish to microplastics containing plasticisers via their food. I then compared their reproductive output to that of fish who do not eat plastics after 5 weeks of treatment. Exposure to the plastic/plasticiser combination cause a halved reproductive output and increased stress at the cellular level.

As plastic pollution in the ocean is becoming a concern in recent times, it is important to understand how plastics may be impacting wildlife big and small. The effect of plasticiser exposure via consumed microplastics is currently unstudied and is an important piece of the puzzle in our understanding the effects of the plastic problem.

In spending the past 3 years of my life with these fish I have learnt a lot about these special fish. For instance, the males are solely responsible for egg guarding and care. For the intertidal species, the male will even stay with the nest when the tide goes out!

These fish can be found in the intertidal zone, the part of the beach which is left uncovered when the tide goes out, as well as in the subtidal seeking refuge within the rocky reeks around the coasts of New Zealand.

Check out iNaturalist to learn more about Triplefins of Aotearoa.


Triplefin Research


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