Source: Te Herenga Waka—Victoria University of Wellington
A research team exploring marine sponges in Fiordland has found half of the 82 sponge specimens collected during a recent trip are new to science.
The discovery of so many new species was “a huge surprise” and exceeded all expectations, said Professor James Bell, a marine biologist at Te Herenga Waka—Victoria University of Wellington and leader of the research team.
“We set out expecting we might find a few new species—if we were lucky. We had no idea of how many different sponges the fiords hold. It seems crazy because we dive so much there, but we have just been swimming past all these beautiful, undescribed sponges,” said Professor Bell.
Sponges play a vital role in the marine environment, recycling nutrients and forming “sponge gardens” that provide habitat for fish and other species.
Dr Michelle Kelly, a sponge taxonomist specialist at Earth Sciences New Zealand, confirmed 41 of the sponge species collected in Fiordland were undescribed and have yet to be named. They add to the approximately 1,700 sponge species already known to live in waters around Aotearoa New Zealand.
The sponges were collected during a research trip in April to investigate the distribution of these animals in Fiordland and how it differs between the inner and outer parts of the fiords. Back in the lab, the sponge specimens were compared with samples of known species held in a collection at Earth Sciences New Zealand.
Dr Kelly described the study of taxonomy—identifying, naming, and describing species—as “like a good Agatha Christie novel, putting all the clues together to get an answer”. Finding new and undescribed species was “very exciting, although not unexpected give the sheer abundance of sponges on the vertical walls of the fiords and the lack of previous formal research on Fiordland sponges,” she said.
Sponge identification starts by creating “spicule preparations”, where sponge tissues are dissolved to reveal the calcium carbonate and silica spicules—tiny parts of the sponge skeleton. These spicules are used along with other characteristics—including shape, colour, texture, mucus production, and even smell—to classify different species.
Dr Francesca Strano, a post-doctoral research fellow at Te Herenga Waka who worked with Dr Kelly, said identifying and describing the new species was crucial for effectively managing and conserving Fiordland’s marine ecosystems, and tracking changes in the environment.
“Species identification takes a lot of time but is really important for managing our oceans, particularly when there is still so much biodiversity we have yet to discover, often just under our noses,” said Dr Strano.
The study is one of the projects of the Southern Fiordland Initiative, a research collaboration aiming to find out more about the marine environment in the fiords and how it is changing. The George Mason Charitable Trust and Te Herenga Waka provided funding for the research.
