Scientist Member Profile - Tom Trnski (Head of Natural Sciences, Auckland Museum)

Both images above taken during the 2011 Kermadec Islands expedition - ©Richard Robinson
Left image - Tom Trnski @tomtrnski spreading rotenone.
Right image - Tom (centre) processing a fish catch with Mark McGrouther @markmcg (right) and Carl Struthers @cdstruthers.
Tom Trnski grew up at a beachside suburb in Melbourne and spent his summers exploring the local rockpools. Once he learnt how to snorkel his interest in marine life expanded and continues to this day. He now studies fishes of the southwest Pacific region, and he is a specialist on the larval stages of fishes – the stage between hatching from their egg to settlement into the juvenile habitat – including their identification and ecology. He spent over 20 years at the Australian Museum, Sydney, before moving to the Auckland Museum in 2007
Tom has published books and scientific papers describing fish larvae and their fascinating life history. He has also led and participated in many surveys of fishes throughout the Pacific, from Indonesia, the Great Barrier Reef, Coral Sea to French Polynesia. In 2011 he led a biodiscovery expedition to the Kermadec Islands with scientists from five different agencies collecting and documenting species. The expedition was the largest of its kind to the Kermadecs – one of the world’s most untouched marine environments – and included discoveries new to New Zealand and to science.
Q: Could you tell us a little about the origins of your interest in nature, especially fish?
A: My immigrant parents were wary of the Australian environment, so my exposure to nature started in my mid-teens through friends who I would bush walk with. This transformed my view of nature and I found an immediate connection; on reflection this was perhaps a spiritual connection that has stayed with me for the rest of my life. I still get a buzz out of being in a remote place in a pristine environment. An undergraduate field botany course in Tasmania helped me interpret landscapes and the drivers of biodiversity.
I was a really poor swimmer as a child and somewhat fearful of the ocean after a near-drowning experience when I was about seven. I grew up in bayside Melbourne and spent summers at the beach, but never too far from shore, but was fascinated by the critters in the rockpools (these same rockpools are now barren of most life!). It wasn't until I was 19 that I learnt to swim distance and SCUBA dive. I did my science degree in Townsville and in second year did a weeklong coral reef ecology subject based at Orpheus Island and this was the beginning of my understanding of marine ecosystems and the pleasure of diving. Diving provided me the opportunity to observe closely the diversity and behaviour of marine life. I didn't realise until I studied science that it was a good fit for me.
After I finished my degree, I moved to Sydney for a year. While working as a barman to make ends meet (what else to do with a marine biology degree?). I started volunteering at the Australian Museum on my days off to maintain my interest in marine science. This led to a few short-term contracts and then to a full-time job there with the fish team. It was this serendipity that aligned me with fishes for the rest of my career. I spent 22 years there supporting and leading research, taking lots of data on fishes, doing collection management, and developing new collection and research facilities. There I had the opportunity to participate in, and later lead, field expeditions to collect fishes, sometimes to remote areas such as Shoalwater Bay in Queensland, the far northern Great Barrier Reef and Coral Sea, and French Polynesia. I have a logistician personality, so these expeditions were a good match to my natural abilities.
My first serious science job at the Australian Museum was working with my research mentor Jeff Leis, describing the development of fish larvae. It resulted in a book on the larvae of tropical Indo-Pacific fishes, which is still relevant today. I subsequently worked on another book describing larvae of southern Australia. After over 10 years of working at the museum, I undertook a PhD on the behaviour and ecology of larval and juvenile fishes.
Q: Why the interest in the Australasia Fishes project and are you contacted to assist with Identifications often? How did you first get involved with our project?
A: My former manager at the Australian Museum, Mark McGrouther, got me started, and hooked, on the Australasian Fishes project. The iNaturalist platform is fantastic, linking citizens to scientists. There are more eyes out there observing nature, and making great contributions to species distributions, behaviour and diversity. I can vicariously participate in these observations through my involvement in the Australasian Fishes project. I enjoy the challenge of identifying fishes, sometimes from imperfect images. I don't always get it right, but the community of experts narrows down the identification options to provide a good data set for analysis. I am quite time-challenged in my current job, so tend to respond to posts that I am linked to, rather than me being proactively searching for posts to identify.
Q: Could you tell us a little about your typical, fish identification process?
A: Interestingly, it is my exposure to larval fishes that has given me the knowledge to identify fishes. Fish larvae often look totally different to the adults. However, there are basic morphological consistencies of meristics (things that can be counted, like vertebrae and fin elements) and morphometrics (relative positions and size of anatomical features). Identifying fish larvae also requires a broad knowledge of the diversity of fishes, to help narrow down the options.
A good quality photograph can be the difference between a rough identification and an identification to species. Ideally a well-lit lateral shot with all fins visible is a winner. But this is not always possible, or only a part of the fish is available (for example some skeletal remains). The best images are also sharp enough to count the spines and rays of the fins; this certainly makes my identification task easier.
Q: Tell us about some of your experiences in remote area research.
A: I have been privileged to have had the opportunity to visit many islands in the South Pacific, often remote or uninhabited. Usually I am contributing to biodiversity surveys of the marine environment with a diverse array of other marine scientists. I have seen some pristine and degraded environments which has fuelled my interest in marine protection and recovery.
Even though I sometimes lead these remote area biodiversity surveys with scientists that have interests in marine mammals, algae or marine invertebrates, my passion is for the fishes. However, I recognise that all of these elements are connected, and I ensure that all interests are accommodated in expeditions.
Most of my survey work is undertaken snorkelling or diving or using ship-based capture methods such as nets, traps, dredges, videos or night lighting. Every method has its biases in what species are recorded so it is important to diversify methods to maximise species diversity.
The most exciting aspect of these surveys is either finding species that have not been recorded from an area before (range extensions) and finding new species. All of these increase our understanding of biogeography and the diversity of life.
I have been challenged many times to identify fishes. With about 20,000 marine species (and a similar number of freshwater species) there is always an unfamiliar species to deal with. Good descriptive guides written by experts are essential tools or the trade.
In identifying fishes for the Australasian Fishes project, I have sometimes made major errors if I have assumed the fish is marine rather than freshwater. So, it is imperative that the locality and habitat details are provided to assist with the identification. I had a recent fail when I assumed a fish was found in marine waters but in fact it was in freshwater, and I embarrassingly was nowhere near the correct identification ( ).
Q: What are your personal, current areas of research?
A: I moved to Auckland 13 years ago, initially to take up a curatorial role. My current role is as head of the natural sciences team at the Auckland Museum. I am the administrative leader of a team of curators and collection management staff. This means that I don't get a lot of time to do research. I manage to remain active mostly through collaboration with other scientists or through student supervision.
My varied research interests, at the moment, include the biodiversity of fishes in the South Pacific region, the drivers of biogeographic patterns, marine restoration, larval fish development and ecology, and the intersect of science and indigenous knowledge. The latter is challenging but also the most fulfilling part of my role. We were recently awarded a $13 million grant to enable an indigenous-led research program at the remote and pristine islands of Rangitahua / Kermadec Islands, which I have the privilege of co-leading.
I have been fortunate to have had a career in museums. Museums have an interesting profile, where research is undertaken, biodiversity is recorded, and the galleries can engage the public on topical issues.
Q: What do you think about the project? Are we making a contribution, and if so, in what areas do you believe the data we are collecting will ultimately be useful, in a scientific context?
A: The Australasian Fishes project is making a great contribution to our knowledge of species distribution ranges and new species records, and sometimes behaviour. The many additional observers have added new observations that would otherwise go undocumented.
This journal post was written by Australasian Fishes member, Harry Rosenthal.
Posted on November 04, 2020 03:56 AM by markmcg markmcg


Very enjoyable read, thanks Harry. I was fortunate enough to work at Auckland Museum for a few years and regularly had contact with the awesome Natural Sciences team. Tom was always super helpful and enthusiastic when I approached him about an ID on a fish observation I'd uploaded to iNaturalistNZ, and I'm proud I was able to add to AM's fish collection thanks to his encouragement.

Posted by jacqui-nz over 3 years ago

@tomtrnski You bio is interesting and inspirational. As well, it is great to see that my hobby (contributions to Inat) is useful to science. Furthermore, I am most delighted to have learned two words that I can use in everyday conversation: meristics and morphometrics. I have not got there yet, but I sense a haiku or perhaps a pop-song with these words... As always @harryrosenthal, wonderful writeup.

Posted by fiftygrit over 3 years ago

Nice one Tommy T!

Posted by anthonygill over 3 years ago

Good one Tom T

Posted by amandahay over 3 years ago

Great to read about you, Tom. I always admire your great attitude and passion for fishes and marine life. Good luck.

Posted by javad55 over 3 years ago

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