The plight of Tasmania’s handfish

The cold waters of Tasmania might seem like a far cry from Indonesia’s treasured critter-dive locations, but for those willing to brave the cold, they hold some amazing treasures. Put on your drysuit, grab your camera, take the plunge, and you just might discover some of the rarest fish on the planet.

Tasmanian dive sites are home to seadragons, multiple seahorse species, but the critters that will convince me to shiver my ass off are the handfishes. Handfish are relatives of the better-known frogfishes, which means to have a similar fishing lure (adapted dorsal fin spines) on top of their head. As the name implies, they also have adapted pectoral fins which resemble hands. Like their frogfish cousins, handfish spend most of their life on the seafloor, waiting for unsuspecting prey to swim by and gobble up.

There are 14 known handfish species, all of which are found only in southern Australia. Unfortunately, 8 out of the 14 species are endangered. One species, the Smooth handfish (Sympterichthys unipennis) even has the unfortunate distinction of being the first marine fish to have gone extinct.

What a fish! The red Handfish (Thymichthys politus) is critically endangered. Photo credit: Tyson Bessell

Other handfish species are not doing much better and might follow in the Smooth Handfish’s unfortunate footsteps all too soon. The Red Handfish (Thymichthys politus), Spotted Handfish (Brachionichthys hirsutus), and Ziebell’s Handfish (Brachiopsilus ziebelli) are all considered to be Critically Endangered. The fate of the Ziebell’s handfish in particular is looking very grim since no confirmed sightings have been reported in 14 years 😦

The sad state of handfish is ironic as, not unlike other endangered or extinct species, they used to be very common. So common in fact, that less than 50 years ago, the local university used them as a model animal for dissections in zoology classes! Early Tasmanian settlers and convicts even considered eating them because they were found everywhere and were easy to collect, but decided against it because they were too small (less than 10cm).

So what went so wrong that we now fear they might go extinct? The main reason for their issues is habitat destruction and degradation. The combined effects of destructive fishing pressures, coastal development, increased pollution and silt runoff means that much of the places they used to thrive are no longer suitable. To add insult to injury, the waters home to handfish have been invaded by the Northern Pacific Seastar (Asterias amurensis). There are now millions of them in prime handfish habitat, and they love to eat handfish eggs and the stalked ascidians the Spotted handfish lay their eggs on. Without a proper place to attach their eggs, the handfish can’t reproduce anymore, with a crashing population as a result.

The critically endangered Spotted Handfish (Brachionichthys hirsutus). Photo credit: Rick Stuart-Smith

Luckily for the handfish, a dedicated group of people are trying their very best to turn its fortunes around. The Handfish Conservation Project is a team of researchers and conservationists that is working hard to save these amazing species. The project has mapped out recovery plans, does research on handfish to better understand how we can help them, and has a citizen science portal to report handfish sightings. In a very cool recent project, science and art were combined successfully to make ceramic egg habitats that are unpalatable for the invasive seastars, but acceptable for handfish to lay eggs on.

If, like me, you want to help conserve these fantastic critters, there’s a few things you can do. If you see Red or Ziebell’s handfish, please report it here, ideally accompanied by pictures. If you can and want to, you can donate to the project here. If you are really keen, you can even name an endangered handfish! For more general info on handfish conservation, the Handfish Conservation Project website is a good place to start.

The Red Handfish (Thymichthys politus) has good reasons to look grumpy. Photo credit: Tyson Bessell

Fieldwork discoveries in corona times: Alor

It’s July 2020 and more than 3 months of COVID19 isolation is starting to grate on me. Time to relive fieldwork from earlier this year, when travel was still possible and exciting research was happening!

My fieldwork season for 2020 promised to be a very exciting one. Not only were we planning to survey coral reefs in Flores with a great team, I even got support from National Geographic to explore some of Indonesia’s most remote reefs.

In the start of March I picked up my genetically-inclined colleague Alessia Bani from the airport in Bali for what turned out to be quite the adventure. We had 2 months of eDNA sampling and exploring ahead of us, mostly in places I had never visited, let alone dived before! Our first destination was Alor, a spot where I had been dying to get to for years.

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Heading to a survey site

Alor is fast becoming known as a place for great muck diving, but also for excellent reefs and even big stuff (hammerhead sharks!). It’s still not the easiest place to get to, but once you get there, oh boy does it deliver! I can honestly say that it has been one of the most enjoyable places I visited in the last 3 years of fieldwork.

We stayed at the very hospitable Air Dive, where our host Acionk and the rest of the team made us feel not just welcome, but part of the Air Dive family. They made our surveys into the easiest and most pleasant fieldwork we’ve done for this entire project.

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A pair of robust ghost pipefish (Solenostomus cyanopterus). Photo credit: Maarten De Brauwer

Our reason for being in Alor was obviously more than just good company. We were in Alor to study coral reefs and collect eDNA. This method is great to get fantastic amounts of data on the diversity of life on coral reefs, but unfortunately it also means very short dives and lots of time spent filtering water at the surface. And trust me, when you’re in Alor, you want to spend as much time as you can under water. While we purposely visited healthy and damaged sites, the abundance of life was great. We had amazing coral reefs, plenty of fish, some very cool critters (frogfishes, ghost pipefishes, plenty of nudibranchs,…). If we could have spent an extra week just fun diving we definitely would have.

The place wasn’t just great under water, there is SO MUCH action on top as well. Alor Strait is home to two resident dolphin pods, one of which frequently hangs out just out front of the place we were staying. We were also lucky enough to see a strong upwelling event, where (very) cold water rises to the surface. As a result, many smaller fish get a cold shock and die or get temporarily paralysed. The sudden abundance of motionless tasty morsels meant a free feast for the dolphins, as well as the local people, who came out with every pot, pan, net, or other random scooping implement of choice.

We finished our non-diving day with a visit to the local dugong, Mawar. Mawar’s name (=Rose) turned out to be a bit of an awkward choice, as this particular rose was a hefty male dugong with anything but delicate flowers on his mind. As we were told, he is the only dugong in the area and gets quite lonely. So any visitors are greeted with overly enthusiastic hugs, which is why nobody is allowed to swim with him anymore. In absence of humans in the water, dear Mawar seems to have taken a fancy for boats. If you want to know just how much of a fancy, let’s say that if I posted some of the pictures I took on this blog, it would probably get taken offline for inappropriate content…

In short, we had a fantastic time in Alor, seeing 9 dive sites was nowhere near enough and I hope to get back sooner rather than later. A big thank you to the Air Dive team, while I am normally not one to advertise dive centres on this blog, they helped us out far beyond what was needed and were just the friendliest bunch of people. Sampai jumpa lagi!

The discovery of the Sodwana seahorse (Hippocampus nalu), Africa’s first pygmy seahorse

I am beyond excited to share the news that with a fantastic team of colleagues, we described a new species of pygmy seahorse!!! Hippocampus nalu, or the Sodwana pygmy seahorse in normal language, is the 45th seahorse species to be described, and the first pygmy seahorse species found in African coastal waters. It’s gorgeous and cute and very tiny.

To explain the story of how such a discovery happens, we wrote an explainer in The Conversation. Just so you wouldn’t have to do effort of clicking the link, I am also sharing the article below, which was co-written by myself, Louw Claassens, Graham Short, and David Harasti. All pictures provided are by Richard Smith.


Before you read this article, pause for a moment and look at the nail on your little finger. That’s about the size of a new species of seahorse discovered in the waters of Sodwana Bay, South Africa, which falls within the iSimangaliso Wetland Park, a World Heritage Site, in KwaZulu-Natal province.

Hippocampus nalu grows to a maximum size of just 2cm. It is the first pygmy seahorse ever discovered in African waters. Our team has conclusively demonstrated that Hippocampus nalu is physically and genetically distinct from the seven known species of pygmy seahorses. Its nearest relatives are found more than 8,000 km away in the Pacific Ocean.

Hippocampus nalu - South African pygmy seahorse, Sodwana Bay

An adult male Sodwana seahorse (Hippocampus nalu). Credit: Richard Smith

Seahorses are threatened all around the world. Many species are at risk of becoming extinct because of human activities such as bottom trawling, over-fishing, and habitat destruction. As a result, several species are listed on the IUCN Red List of Threatened Species. However, to date no pygmy seahorses are considered threatened – because we simply do not know enough about them. By discovering more species, and learning more about these tiny creatures, scientists can offer advice on how best to protect them.

Pygmy seahorses can also provide an important boost for tourism: scuba divers love these small species and are willing to travel far and wide for a chance to see them. If coastal communities and scuba divers alike are taught about the best ways to protect these species and others in the oceans, there can be huge economic and social benefits.

The most astonishing part of this discovery is that it didn’t start in a laboratory, or with keen scientific minds assessing the likelihood of finding a pygmy seahorse in African waters. Instead, it began with a photograph.

Tracking the seahorse

Dr Louw Claassens and Dr Dave Harasti arrived in Sodwana in early 2018 looking for an entirely different animal: a seahorse-like species called a pygmy pipehorse. But then a local dive guide named Savannah Olivier showed them a photograph of a very small seahorse. The scientists recognised it as a pygmy seahorse, which are supposed to live an entire ocean away. South Africa is home to four other seahorse species, but this was the first time a pygmy seahorse had been observed in South Africa, let alone Africa.

Nine months later Louw returned to Sodwana Bay, this time accompanied by Dr Richard Smith, a pygmy seahorse expert. They, with Olivier, found a pair of the tiny pygmy seahorses along a rock face at about 15m depth. The little creatures were grasping on to slivers of algae amid raging surging seas. The reefs of Sodwana Bay are exposed to the swells of the Indian Ocean, very unlike the more sheltered coral reef settings in the tropical Pacific where the other known pygmy seahorses are found.

Later they even found a tiny juvenile measuring just a centimetre in length, which was dwarfed by a diver’s finger.

Juvenile Hippocampus nalu - South African pygmy seahorse, Sodwan

Juvenile Hippocampus nalu – South African pygmy seahorse, Sodwana Bay. Credit: Richard Smith

Finding the seahorses was only the first step in describing the new species. The rest of the team now got to work. Graham Short, a researcher at the Australian Museum and California Academy of Sciences, compared the mystery seahorses with other pygmy seahorse species by looking at their characteristics under a microscope, as well as a powerful CT scanner. Dr Mike Stat, a geneticist from Australia, used genetic methods to test how distinct it was from other species. Through combined team efforts, we confirmed that the Sodwana pygmy seahorse was a new species and could give it an official scientific name.

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CT scan of the Sodwana seahorse (Hippocampus nalu). Credit: Graham Short

The name “nalu” has three layers of meaning. In the local isiXhosa and isiZulu languages it means “here it is”, to show that the species had been there all along until its discovery. “Nalu” is also the diver Savannah Olivier’s middle name. Finally, “nalu” means “surging surf, wave” in Hawaiian, which hints at the habitat the species lives in.

More to learn

The discovery of the Sodwana pygmy seahorse is exciting for more than just its scientific value. It provides new insights into the global distribution of these tiny fish and paves the way for further exploration in other locations. Only a handful of research publications focused on the ecology of pygmy seahorses exist, so anything we can learn more about these critters will help the future conservation of this unique group.

Finding a species like Hippocampus nalu also shows how little we know about Africa’s marine biodiversity, and how much more is left to discover. It highlights how important the observations of keen amateurs are to help scientists. If a keen fisherman did not consider a strange looking fish caught off the south coast of South Africa worth sharing with Marjory Courtney-Latimer in 1938, the discovery of the coelacanth, a living fossil, might never have happened.

Similarly, without a diver’s sharp eyes and an expert’s initial questions, the world would still not know that the Sodwana pygmy seahorse exists. As scientists, being open to questions from the general public not only helps inform non-scientists, but can also help us make new discoveries.

Hippocampus nalu - South African pygmy seahorse, Sodwana Bay

 A female Hippocampus nalu. Credit: Richard Smith