Diving out at the Hen resulted in finding this unusual species Tripneustes kermadecensis. We dove into multiple spots throughout the day. The final spot was remarkably desolate in terms of kelp and encrusting organisms compared to previous areas. However, it was populated by these spectacular looking urchins. Very different in size and colouration from our classic “Kina”. Before further investigation I had no knowledge about this sea urchin but it was certainly worrying to see its anomalous appearance coinciding with a fairly unhealthy looking reef. Correlation is not causation but I feared this species was partially responsible for the reef condition, possibly even an invasive species from seas far away. Upon talking with a friend he was able to positively identify it as Tripneustes kermadecensis, allegedly abundant in the upper reaches of New Zealand waters especially the Kermadec islands. Finding the species this far south could be considered unusual but may be observed more frequently due to warming oceans allowing these urchins to potentially extend their range poleward towards mainland New Zealand. The environmental effects are currently impossible to quantify but it would likely have a disruptive effect on currently established populations as they compete for the same resources. I would generally advocate not killing things if you don't know what they are, and consider it as a lapse of judgment on my part to end this urchin. Perhaps they were responsible for the sparse kelp bed and barron rock or perhaps not, time will tell. At the very least a friendly sanddaggers wrasse got a good feed and this video should serve to bring some attention to one of the less highly regarded phylums, Echinodermata. There are plenty of fish in the sea, but plenty of other things also. As a spearfisherman it can be easy to overlook anything besides fish and sharks but the ocean is a great puzzle and we are still learning how all the pieces fit together.
Diving out at the Hen resulted in finding this unusual species Tripneustes kermadecensis. We dove into multiple spots throughout the day. The final spot was remarkably desolate in terms of kelp and encrusting organisms compared to previous areas. However, it was populated by these spectacular looking urchins. Very different in size and colouration from our classic “Kina”. Before further investigation I had no knowledge about this sea urchin but it was certainly worrying to see its anomalous appearance coinciding with a fairly unhealthy looking reef. Correlation is not causation but I feared this species was partially responsible for the reef condition, possibly even an invasive species from seas far away. Upon talking with a friend he was able to positively identify it as Tripneustes kermadecensis, allegedly abundant in the upper reaches of New Zealand waters especially the Kermadec islands. Finding the species this far south could be considered unusual but may be observed more frequently due to warming oceans allowing these urchins to potentially extend their range poleward towards mainland New Zealand. The environmental effects are currently impossible to quantify but it would likely have a disruptive effect on currently established populations as they compete for the same resources. I would generally advocate not killing things if you don't know what they are, and consider it as a lapse of judgment on my part to end this urchin. Perhaps they were responsible for the sparse kelp bed and barron rock or perhaps not, time will tell. At the very least a friendly sanddaggers wrasse got a good feed and this video should serve to bring some attention to one of the less highly regarded phylums, Echinodermata. There are plenty of fish in the sea, but plenty of other things also. As a spearfisherman it can be easy to overlook anything besides fish and sharks but the ocean is a great puzzle and we are still learning how all the pieces fit together.
The Fish Really Likes It😊 Respect
Shouldve done a taste test.
Maybe next time haha. Wasn’t sure about it but have since heard they are good eating!