5 minutes with Jeff Johnson, Senior Collection Manager and Ichthyologist

On average there are around 30 new fish species from Australian waters described annually – how fin-tastic! Spend 5 minutes with Jeff Johnson, Senior Collection Manager of Ichthyologist and find out what his favourite collection item is.

What is your favourite object/species in the collection and why?

My favourite collection object is a pair of dried vertebrae from a huge White Shark, Carcharodon carcharias. The specimen is the oldest extant zoological item in any Australian museum and, if the labelling is correct, would be from the largest White Shark ever recorded. The original handwritten label reads “Vertebrae from 28- foot Great White Pointer, Derwent River, Van Diemen’s Land, 1830”. The actual length of the shark cannot be accurately validated without knowing the position in the vertebral column that the vertebrae were excised from – in any individual those in the anterior portion being significantly wider in diameter than those at the rear. Based on validated scientific data, it seems unlikely that the shark was 28 ft (8.5m), unless these were the narrowest vertebrae in the shark. This all goes to make this specimen historically significant, scientifically challenging and intriguing.

Do you have any interesting facts about your specialty area?

Fishes are by far the largest group within the vertebrates. With about 35,000 species worldwide, they comprise more species than all the mammals, birds, reptiles and amphibians put together. There are more than 5,000 fishes recorded from Australian waters, with about 30 or so additional ones newly described, or recorded, each year.

The largest living fish is the Whale Shark, Rhincodon typus, reaching at least 12 m. The smallest fish is subject to some debate, according to whether this should be the shortest, or that of least weight, however the title should probably go to the Stout Floater, Schindleria brevipinguis, a relative of the gobies from the Great Barrier Reef, which reaches 7 to 8 mm in length and about one millionth of a kilogram. 

Perhaps the strangest fish to be found in Australian waters is the parasitic male of the Southern Seadevil, Ceratias tentaculatus. On maturity the tiny males of this deep-sea anglerfish permanently attach to the body of the much larger female…so as to be always available for mating!

Weirdest item in the collection, apart from various grossly deformed specimens, would probably be a cross-section from a very solid plank of wood washed up on the beach near Cooktown. It has the tip of a marlin’s snout firmly imbedded in it! One could only imagine the force necessary for the bill to penetrate a floating plank and snap off. Ouch!    

On average there are around 30 new fish species from Australian waters described annually. Many more could be described, if there were sufficient ichthyologists available with the time to describe them! The process of describing fish species is time-consuming and not always straightforward. Detailed examination is required, often using both morphological and genetic analysis, and rigorous comparison with similar existing species is needed.   Many species have been flagged as undescribed for years, but are awaiting an ichthyologist with specialist knowledge of the group to devote the time to formally name them. Among the fish species that I have specialist skills in (particularly sweetlips, sand perches, soles, waspfishes and velvetfishes) there are at least 12 new species that I am currently aware of.     

Tell us a little bit about Ichthyology  and why do you love working in this specific research area?

There are so many and varied facets to the study of Ichthyology. Collection-based ichthyologists in museums have traditionally focussed on taxonomy (classification and identification) and distribution of species, however we field queries about a much wider range of topics. Dangerous species, poisonous and venomous species, invasive species, species with expanding ranges due to climate change, details on ecology and reproductive biology, just to name a few. Providing authoritative, high quality advice and information to the general public, government authorities, industry, media and scientific community is a constant source of inspiration. 

What is your favourite thing about your role at the museum? Why?

Making new discoveries of things that have long confounded other experts, and seeing the results through to peer-reviewed publication is very satisfying…as is solving a tricky public enquiry and getting a “thank you, I would never have guessed that” response.

What is one of the most interesting facts you have discovered through working at the museum?

The museum has a wealth of highly-talented people whose expertise within their chosen field is often unsurpassed both nationally and internationally. Being a little eccentric sometimes goes with that territory.

Learn more about Jeff Johnson here.