Going Down Under: Caving for Fish in Australia

November 2009

         In May and part of June, I traveled to Western Australia for a three-week trip that was equal parts collecting, museum work, and fish conference. For this trip I had to go down under, literally. The first part of the trip involved entering some tight subterranean habitats in search of blind cave fish. The second part of the trip was working up some bioluminescent fishes collected for me at the Western Australia Museum in Perth and the third leg was the Indo-Pacific Fish Conference in Freemantle. It was a very interesting and worthwhile adventure all around. This trip was also notable at a personal level because I was able to have my wife, Annemarie Noël, join me. I’ll spare you the details about the conference (I won an award!) and museum work (I found a new species!) so that I can focus on the collecting.

         The collecting trip was nearly derailed before it got started. Despite more than six months of planning and negotiation, my permits were nullified at the last minute. The permits were voided because of a miscommunication between the Western Australia Museum (WAM) and the Australian government. The timing could not have been worse; I got the news via e-mail the Friday before I was to leave. Because our Friday morning is already Saturday in Australia, I was unable to remedy the situation before my flights. I spent the entire time traveling to Australia worried sick that I wouldn’t be able to collect. After flying for what seemed like three days (actually only two days) and finally arriving in Perth I immediately called the collection manager of the WAM. She explained that there was a terrible misunderstanding and that she would talk to the government to reinstate my permit. Unfortunately the new permits were much more limiting than the originals, but certainly better than nothing.

         The next morning Annemarie and I boarded a flight to Exmouth, which is about 1300km north of Perth. The town of Exmouth is in the Northwest Cape, a small peninsula that is nearly the most western tip of Australia. Around that peninsula, also called Ningaloo, is the only part of Australia with cave fish. Their habitat is distributed around the few hundred kilometers of the peninsula. Only one species is known, Milyeringa veritas, commonly known as the blind gudgeon. Based on some preliminary work I suspect that there is more than one species. These fish are poorly known and the populations are likely much bigger than the few specimens we find in caves. Their real homes are the inaccessible underground water chambers that span many kilometers.

I became interested in blind subterranean fishes after collecting them in parts of Madagascar last year. The first thing I noticed about the Northwest Cape of Australia is how much it resembles Southeastern Madagascar. Both locations are dry landscapes with a bright maroon colored soil, baobab trees and short stubby brush. The other thing they have in common is the presence of blind, pigment-less, subterranean fishes. From my previous work I learned that the closest relative of the blind fishes in Madagascar are the blind fish in Australia. These helpless blind aquatic animals can’t travel 10 feet out of the caves let alone across the Indian Ocean. Their long history of living underground and being isolated from predators made pigment and vision unnecessary. The only explanation for the disjunct distribution of this Malagasy/Australian lineage is that these fishes were once part of a continuous landmass that subsequently broke apart. That former continuous landmass is known as Gondwana, and it included both Australia and Madagascar and possibly the common ancestor of these fishes. These fishes are part of a lineage that has survived the 130 million years since the break up of Gondwana. They’ve managed to survive in isolation oblivious to the changes above ground. The extinction of non- avian dinosaurs, bolide strikes, climate change, and the rise of humanity has not caused them to blink an eye (if they had eyes to blink).

On our first collecting day, we went to six locations where Milyeringa had been collected previously. At our first site, Woburi Rockhole, we drove a little bit off the road in Exmouth to a small hole in the ground that led to a larger underground chamber. We had to shimmie down a metal pole that was rigged up for cave divers to enter from above into the water below.

         As we entered you could see fossil marine shells in the limestone deposits lining the walls of the entrance. Inside the cave, which was tiny compared to what I experienced in Madagascar, we saw eight specimens of Milyeringa veritas. I was glad to have Annemarie with me as this was her first experience with caves. Inside the cave we found the skeleton of a large kangaroo that must have fallen into the cave about a month earlier. We were lucky we didn’t discover it a week earlier because it was surrounded by thousands of fresh fly egg casings. It will make for a fine fossil one day. We spent about a half an hour in the cave before moving on. The next sites were mostly wells that were built next to small enclosed caves. Aboriginals had used the caves to get ground water for hundreds of years and you could still see the shards on the ground from the shells they once used to bring up water. Later settlers built wells for easier access to the water. I shimmied down some of the wells by pressing my back and hands against the wall while my feet were pressed against the other side. In other wells our guide, the wonderful spelunker Darren Brooks, used repelling equipment to drop sometimes more than 30 feet to get to the water and fish below.

         The most interesting cave was a site we entered on the second day. At first glance I thought it would be impossible to enter. The entrance was just two small holes, one that looked to be about 45 inches around and the other perhaps 15 inches around. Neither looked particularly inviting. The larger opening and the tunnel below were so tight that I needed to take my helmet off in order to fit. The cave itself was shaped like an Erlenmeyer flask with a tight elbow shaped entrance. After dropping a small chain ladder down the hole (making the entrance even tighter) we slowly slipped down about 15 feet into a small pocket that led to a short horizontal shelf that led to another drop of 15 feet into the main chamber. This chamber was filled with water and luckily a couple of blind gudgeon. We needed the ladder for the last drop because there was nothing to grab onto for the last ten feet. The bowl shaped chamber was dark and damp and the high CO2 levels meant that we couldn’t stay there very long. We collected a single specimen from that cave and headed back out. The climb back out of that cave was one of the scariest most physically challenging things I’ve ever done. After climbing out of the first chamber relatively easy I made a stupid mistake and tried to exit by climbing out facing a different direction than I had gone in. I found myself stuck like a fly in a pitcher plant.

I could feel the cool air above me but I couldn’t move my arms above my head nor could I move my knees to leverage myself upward. It was extremely claustrophobic and terribly frustrating. After doing the equivalent of a hundred push ups and making no progress in getting out I headed back down to turn around. Finally, after 15 minutes of scraping myself against limestone and brushing biting ants from my face, I got out. All for a little blind fish – but in the end it was worth it. (My wife took excruciating video of my progress out of the cave that nobody reading this will ever see.)

The collecting part of the trip was much shorter than I had hoped but I gained enough materials to do what I had intended. Before heading to Perth Annemarie and I decided to do something completely different from hunting little three-inch fish in holes. We went swimming with the largest fish, the whale sharks. After dealing with dark and tight spaces it was great to actually get into the great Indian Ocean and follow some 20 foot sharks around for a day. The remainder of the trip was also fruitful and enlightening but nothing will be as memorable as our time in the Northwest Cape.