Australasian fishes's Journal

Journal archives for February 2018

February 1, 2018

Manta Malady

I wasn't sure what I was seeing in this observation taken by Kate Malcolm (Dive! Tutukaka) until Clinton Duffy explained.
The image shows a large Manta Ray, Mobula birostris and six Yellowtail Kingfish, Seriola lalandi. Clinton pointed out the hook that wraps over the upper jaw and the trailing fishing line that runs along the fish's back. He noticed that there are several large clumps of encrusting organisms on the fishing line. These and the line are abrading the skin in a couple of places leaving long white scars.
While this is an unfortunate occurrence, it was presumably accidental and the hook should corrode away in time. Hopefully the fish won't be affected too badly in the meantime.
Both Mobula birostris and Mobula japanica are protected in New Zealand waters, where Kate's observation was made. Kate stated, "We see a load of life at the Poor knights - more mantas than ever this summer, and more turtles than ever the winter just gone."
Postscript:
Kate has now uploaded a video that clearly shows the fishing line and the injury it is causing.
Posted on February 1, 2018 01:52 AM by markmcg markmcg | 15 comments | Leave a comment

February 7, 2018

Clingfishes meet Seadragons

This terrific observation was made by Andrew Trevor-Jones Thank you Andrew!
The images show an Eastern Cleaner Clingfish, Cochleoceps orientalis on the side of a Common Seadragon, Phyllopteryx taeniolatus. The observation was made in January 2018 at 'The Leap', Kurnell, Sydney. Andrew has dived at this location more than 250 times over the last 7 years.
He stated, "I have seen cleaner clingfish on common seadragons and pot-bellied seahorses a few times. I often don’t see them until looking at the photos but in this case I did see it and moved in for closer shots - as close as the seadragon would let me." View more of Andrew's images of Clingfishes on Common Seadragons and Seahorses.
The stomach contents of the Eastern Cleaner Clingfish have not been analysed but judging by its behaviour, the contents should be similar to those of the Western Cleaner Clingfish, Cochleoceps bicolor. This species feeds mostly on small crustaceans (predominantly isopods) which it presumably picks off the fish it 'cleans'. Other bits and pieces on the host's skin as well as mucous may also be consumed.
I consulted clingfish expert Dr Kevin Conway about another one of Andrew's observations which shows a different species of clingfish on a seahorse. Kevin stated that based on the shape of the snout, the fish is not an Eastern Cleaner Clingfish. The colour pattern would suggest that it may be a Pink Clingfish, Aspasmogaster costata. Kevin reported that there are several other species of clingfishes that have also been reported to clean larger fishes, including species in the genera Lepadogaster and Diplecogaster.
The Common Seadragon is endemic to Australian temperate marine waters. It occurs from the central New South Wales coast around the south coast of Australia to south-western Western Australia. The Eastern Cleaner Clingfish occurs in most shallow New South Wales marine waters. It is known from Seal Rocks, New South Wales to Mallacoota, Victoria.
Posted on February 7, 2018 03:28 AM by markmcg markmcg | 4 comments | Leave a comment

February 19, 2018

Rays gettin' some rays

This observation 'blew me out of the water'!
The fish are Mangrove Whiprays, Himantura granulata.
Javier Delgado Esteban stated, "On the 3rd day working on my project I recorded a group of around 20 to 30 juvenile Whiprays resting under a mangrove tree's shade at high tide. I spent a couple of hours in the water with them being very still until they seemed to get used to the click on my shutter, some were less shy than others and were happy to be very close to the camera. I observed that they seem to emit a very dry clap and I was wondering if this was some form of communication as that is what appeared to me."
Javier has uploaded video footage to the Australasian Fishes YouTube Channel. The clicking sound is clearly audible in the video. View all of Javier's observations of this species.
According to Helfman et al (2009), "Sound production occurs in well over 50 families of cartilaginous and bony fishes." A number of different mechanisms are used to generate sound, ranging from grinding of teeth, to 'sonic ligaments' through to 'fish farts'. For this short blog I have not done any investigation into the sound production in rays. I think it would be a fascinating area of research.
Javier's excellent photographs have earned him several awards, as can be seen on his LinkedIn page.
Thank you Javier! Your patience and skills have resulted in a fascinating observation.
Reference:
Helfman, G.S, Collette, B.B., Facey, D.E. and B.W. Bowen. 2009. The diversity of fishes: biology, evolution and ecology. 2nd edn. Wiley-Blackwell, Chichester. Pp. 720.
Posted on February 19, 2018 04:59 AM by markmcg markmcg | 5 comments | Leave a comment

February 28, 2018

Member profile - Gina Mascord

One of the inherent delights of citizen science projects is the realisation of how many people share your interests and passions about the natural world. Citizen science projects like Australasian Fishes not only provide valuable data from the scientific community, expanding our knowledge of fish ranges and behaviours, but also create assemblies of like-minded individuals who otherwise, due to distance or schedules might have never engaged each other. This creation of community, through citizen science promotes mutual support, fosters learning more about the science at hand and provides insight into what drives people to develop from their sport of diving, snorkelling or fishing into someone interested in the science of their environment.
Gina Mascord learned about the project through a presentation at her local dive shop. This was highly appropriate as she strongly believes in the value and benefits of supporting local dive shops, which are suffering from the onslaught of on-line retail and an increasingly challenging business environment. Born and raised at Catherine Hill Bay, south of Newcastle, her early engagement in sports started with soccer and netball, which are both hard on the body, and eventually resulted in injury. Eventually she sought activities that took less of a physical toll and fed her lifelong interest in marine science. She found her way in to a dive shop only 12 years ago, discovering the sport which has become her passion. Diving offered her the ability to remain active and engaged in a demanding sport, while reducing the overall physical impact on her past injuries. This has been a fortunate development for citizen science. Bringing a highly competitive, sporting mindset and motivation to diving, she did not take her underwater activities lightly. Through a local dive shop, she first took basic courses which fueled her interests as she progressed through subsequent courses all the way to Dive Master. The support for the dive shop and the club it formed continued to fuel her interests, which shifted to underwater photography, and she now explores the local ocean in the Swansea area of New South Wales. Sadly, she’s seen six dive shops close in her area, and confides she treats her current shop as “home” as she recognises that such support of the local is critical for the success of sport diving and the vitality of such citizen science projects as ours.
The shops also serve as seeding grounds for important underwater initiatives. For example, Gina is a member of a volunteer group called Combined Hunter Underwater Group (CHUG). The group is involved in a substantial amount of citizen science work, regularly posting images on RedMap , SharkBase, Spot a Shark and now Australasian Fishes. She is currently ranked as number 11 on the project leader board, sharing 561 observations of 152 different species. This is actually remarkable as she only joined the project six months ago, with the expressed objective of being in the Top 10. Did I mention she was competitive?
Ask her about sharks. Gina, while interested in all animals, has always harboured an active concern for these predators. Her personal outrage at the activity of shark finning for soup, which culls tens of millions of sharks a year, has prompted her to sport a distinctive tattoo on her back (photo above) which decries this practice. It serves as catalyst for conversations about the subject, providing her an opportunity for a teaching moment about the barbarism of shark finning.
Since she was a child, she’s had an unwavering love of the ocean, and in her youth aspired to become a marine biologist. While this did not occur, even as a child and with little formal training, she still developed the discipline to research items found on the beach that she found interesting. Gina’s father encouraged her by suggesting she identify items she beachcombed, using books and other resources which refined her research skills. From an early age, she was citizen scientist in development, and our project has benefitted from her passion and discipline.
While the majority of Gina’s photos are from the Swansea area, she travels frequently, making dive trip plans based upon the locations of the marine animal she wishes to photograph. Her recent collection from South Australia features some amazing fishes and her favourite dive sites include Bali (Tulamben) and Fiji (The Rainbow Reef). She also loves Thailand, PNG, the Solomons, Vanuatu, and of course, the Great Barrier Reef.
For photography she currently uses a Cannon G16 with a Recsea housing. She likes the housing because it is made from one piece of metal, with no seams to crack or leak. For light she uses a SeaLife Sea Dragon strobe and a Sea Dragon 2000 video light. She encourages all underwater photographers to purchase a strobe for better light definition, but also suggested post production using Photoshop or Lightroom. We encourage you to have a look at her photos , and feel free to contact Gina for advice or comments.
This journal post was written by Australasian Fishes member, Harry Rosenthal.
Posted on February 28, 2018 01:11 AM by markmcg markmcg | 4 comments | Leave a comment