יומן של Australasian fishes

ארכיון יומן של ספטמבר 2023

ספטמבר 7, 2023

Scientist Member Profile - Dr Anthony Gill

Collecting fish for aquariums was a popular hobby for many living near oceans, streams or lakes. Learning how to catch, transport and support wild fish in enclosed tanks in your living room was a challenging and educational exercise, especially for the young hobbyist. The first bed I learned to make was the seabed, in my aquarium. Other lessons as a hobbyist included learning about fish habitat, avoiding fish stress but most importantly, how to clean up the living room floor when the bottom fell out of my large tank one evening. Holding the dog back was a key step.
Even today, I have friends who collect marine tropicals, washed down the coast by currents, which will not survive the winter in their new, more temperate waters. I hear that most them, while in captivity, do survive and adopt to a new life, living in a tank, far south of their normal homes on the Great Barrier Reef. I do look back fondly on my days as a boy, collecting fish for display in my home aquarium, and believe that it must have played a role in developing my interest in fish today. It was a nostalgic pleasure to learn that the subject of this edition of our Bio Blurbs, Dr Anthony Gill, (@anthonygill), had similar experiences with fish as a youth. Unlike me, however, having a fish collection inspired Tony (as he is known by most colleagues) to study the world of fish taxonomy, launching a career which had him working in some of the world’s great museums, such as the Smithsonian and the British Museum.
He tells us of his early days, “I grew up in Muswellbrook in the Upper Hunter. I guess my interest in nature was initially through fishing with my dad in the Hunter River. My dad used to get annoyed with my strategy of slowly retrieving my line back through the shallows so I could catch "rubbish fish" (mostly eleotrids, a group that I would later publish on). These often ended up in my fish tanks, which I started keeping when I was about five, and I soon had a bunch of aquariums and a (still) growing library of fish books. I loved fishing on the coast (mostly at Pelican, Swansea Channel), but being a country boy, was terrified of sharks! On my 14th birthday I joined the Newcastle branch of a marine aquarium society (M.A.R.I.A. - Marine Aquarium Research Institute of Australia). That night, after the society's monthly meeting, I did my first snorkel ... ironically, in Swansea Channel. It was terrifying for me (not helped by a makeshift dive light that kept going out), but I was amazed by the diversity of fishes. Members of the society used to hold regular field trips, where they would collect fishes for their aquariums, mostly juveniles of tropical species that would not survive in the wild beyond mid-winter. At that time (mid 70s) there were few identification resources, particularly for juvenile fishes, so we often didn’t know the species until they had grown a little in our tanks.”
Tony has been involved in Australasian Fishes since the project first kicked off. He tells us, “I’ve known Mark ever since I had an internship at the Australian Museum over 40 years ago. We’ve also conducted fieldwork throughout NSW. My taxonomic research is mostly on Indo-Pacific fishes with much of my effort concentrated on Australian fishes. Aside from that research, I have a fair knowledge of live identification of most groups thanks also to fieldwork with Jeff Johnson in Queensland and Barry Hutchins in Western Australia. I enjoy contributing to the project, and more generally to iNaturalist fish identifications.”
Tony has made almost 10,000 identifications on iNatrualist, of that total, almost 4,000 are for the Australasian Fishes project. As one of the project’s experts in fish taxonomy, he is someone to whom the project owes a great deal. I asked Tony how he goes about identifying a rather difficult fish to classify. How does he start and what process does he follow? He responded, “It depends a bit on the species involved, but the first step is always to get it to a broader category such as genus or family. That can be very difficult for someone starting out, as it’s something that mostly relies on experience. There are characteristics of course for distinguishing genera and families, but often these aren’t visible in photographs. Instead, you rely on the “gist” of the fish, things that you probably can’t list or recall … “that’s a wrasse because it looks like a wrasse.” Probably things like scale size, fin shapes and positions, mouth size, and body shape play a large role in getting through that first step. Beyond that, it’s a case of matching colour patterns, fin-ray counts, scale counts or whatever to get past family or genus to species identification. All these characteristics are best viewed from a lateral perspective, which means photos that show fishes in other positions (or with bits obscured) are more difficult to identify. Shots where the fins are erect will often allow fin-ray counts to be checked. Coloration often varies, depending on whether the fish is photographed at night or during the day, or whether it’s stressed, alive or dead, or in courtship colours, or a juvenile versus an adult. Sometimes a dead fish is easier to identify because that’s how that species is always depicted in identification resources; other times stress coloration can make identification difficult or impossible. Above all, accurate species identification is possible only if the taxonomy is reasonably well-resolved, and there has been appropriate linking of studies of museum specimens to live ones.”
To those of us familiar with fish identification, it appears a lot of taxonomy has gone down the genetic route, rather than the traditional physical inspection process. As Tony has a passion for fish identification, I was curious how he is dealing with the change in scientific techniques. He tells us, “Yes, molecular techniques have become the mainstay in taxonomy, with fewer and fewer people being trained in morphological methods. This is unfortunate, as we live in a morphological world, and don’t experience it through those kinds of methods. I’m very much in favour of these techniques as tools in taxonomy, but they need to be coupled with proper morphological work. Unfortunately, morphological taxonomy is often slow and painstaking, and dependent on slowly acquired taxonomic understanding of a given group. This contrasts with the emphasis on technological expertise, which allows molecular taxonomists to switch rapidly from one taxonomic group to another and to deliver quick results without any particular need for morphological knowledge of the species in question. Aside from the obvious need for greater support for morphologists, this problem also highlights the importance of citizen scientists in contributing to biodiversity research. There are many amateur contributors on the Australasian Fishes project that are very proficient at identifying fishes. The iNaturalist platform is not only important for citizen scientists to express their skills, but also a venue to improve them.”
Currently, Tony is the Natural History Curator, Macleay Collections, at Sydney University’s Chau Chak Wing Museum where he busily looks after the museum’s natural history collection as well as develops new exhibitions. He tells us, “Currently I’m working on a display on pigeon and dove taxonomy, which will be installed in a few months. As a spin off from that, I’m going through historical records trying to develop a database of first nation names for our bird collection. My fish research is done mostly in my spare time and vacation time. For the past few years it’s concentrated on the taxonomy of anthiadine seaperches, but I’m also continuing work on dottybacks and gobioids that I began decades ago.”
Among the reasons Tony contributes to the project is not only to keep his personal taxonomy skills razor sharp, but also because he strongly believes in citizen science and the work of Australasian Fishes. In his own words, he tells us, “ (Australasian Fishes) is making an enormous contribution to our understanding of our fish fauna. The obvious contribution is in our understanding of species distributions. Perhaps even more important from my perspective as a taxonomist is the information that the photos provide in terms of colour variation. Often this leads to the need for taxonomic re-evaluation of species because the photos draw attention to geographic variation that suggests currently recognised species may be complexes of similar species. Moreover, even the most field-active scientists don’t get to see fishes alive all that much; citizen scientists provide more eyes in the water.”
Tony reminds me of the importance of having “more eyes in the water”, which is better than more eyes on my fish collection flopping around on the living room floor. By family majority vote, I gave up having large aquariums, as it was only me and the dog who thought trying again would be a worthwhile effort. Australasian Fishes is grateful for Tony’s long running support and it is pleasing to meet someone who’s career was fueled by their experience with aquariums, using them as a stepping stone to a rewarding career in the natural sciences.
This journal post was written by Australasian Fishes member, Harry Rosenthal.
הועלה ב-ספטמבר 7, 2023 02:25 לפנה"צ על ידי markmcg markmcg | 3 תגובות | הוספת תגובה

ספטמבר 12, 2023

Japanese Threadfin Bream sighting at Fairy Bower

A juvenile Japanese Threadfin Bream, Pentapodus nagasakiensis, was recently photographed at Fairy Bower, Cabbage Tree Bay, Sydney. The sighting was made by John Sear on March 28, 2023.
This observation was made more than 1300km south of the recognised southern limit to the distribution of the species, which is Swain Reefs, Queensland (21°16'S). View the Australian Faunal Directory factsheet.
John stated, "This fish was at 9m depth. Being familiar with a couple of Pentapodus species that we find in the Aquatic reserve, I knew this one was a different species and one I haven't encountered before. A quick search through some reference books found it but I was quite surprised to see so few observations on iNat, and the range extension."
Thank you John for uploading this important observation. Thanks also to Threadfin Bream expert Dr Barry Russell (@ichthysau) for confirming the identification of the fish.
הועלה ב-ספטמבר 12, 2023 10:24 לפנה"צ על ידי markmcg markmcg | תגובה 1 | הוספת תגובה

ספטמבר 21, 2023

Princess Damsel way out of range

What the heck! John Sear has developed quite a habit of observing and documenting fishes south of their 'official' distributions. The southern limit to the distribution of the Princess Damsel, Pomacentrus vaiuli, is Moreton Bay, Queensland. This fish was observed more than 700km further south.
When asked about this remarkable observation John stated, "Re the P. vaiuli observation, last summer was an especially exciting one as far as species being observed outside their normal distribution ranges. Cabbage tree Bay aquatic reserve is a particularly good refuge for species that have had a ride down the eastern coast on the EAC, and last summer was particularly good for spotting damselfish species. This one was in close proximity to several other species that are not commonly spotted in the area, hiding amongst the rocky reef. It's colouration differentiated it from the more commonly found species, though identification required participation of more experienced fish gurus on iNat. Spotting new arrivals is easy, but confirmation of identification often requires expert input as was the case with this one."
As John said, there was some uncertainty about the identity of the fish, in particular whether the fish was P. vaiuli or P. bankanensis. We consulted the damselfish expert, Dr Gerald Allen who confirmed that the fish was indeed P. vaiuli. Thank you to Gerry for sharing his expertise and to John for another great contribution!
הועלה ב-ספטמבר 21, 2023 04:22 לפנה"צ על ידי markmcg markmcg | 6 תגובות | הוספת תגובה

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