Archivos de Diario para septiembre 2017

13 de septiembre de 2017

Member profile -Sascha Schulz

All citizen science projects like Australasian Fishes thrive only through the passion and dedication of numerous talented people.
Over the life of the project we hope to highlight the rich diversity of expertise, various backgrounds and deep passions of some of the 500 plus citizen scientists who are contributing to the knowledge of our region’s fishes by their dedication, time and tenacity.
Sascha Schulz was an early contributor and supporter of Australasian Fishes who personifies this non-professional dedication to advancing knowledge of our fishes. His name would be familiar to anyone accessing the Australian Museum’s website as his photographs are featured on many species fact sheets.
Most viewers might not recognise the dedication to citizen science which underlies Sascha's work on the project. At the time of this writing Sascha was ranked third in total observations, with almost 1,400 observations, which covers an impressive 438 different species!
Sascha tops the leader board in identifications, a generous and key component of the project. He has assisted in the identification of almost 7,800 individual observations. His skill in identification goes back to the days when he worked at the Australian Museum, leaving him with an eye for detail and an ability to pick out features, often from less than perfect photos. Many observers have found his efforts rewarding and he’s often one of the fist identifiers to recognise that a fish was photographed outside its range. He has over 1,000 books and papers on fish in his home, and keeps current with scientific papers on fish distributions and their taxonomy.
Sascha is one the project’s polymaths, with degrees in marine biology and electrical engineering. His skills are supported through very traditional underwater methods. All his photos are taken on mask and snorkel, holding his breath, as he explores marine and estuarine areas, looking for unusual species or a taxonomic challenge. He has been freediving since 1996, and feels a great connection with the marine environment. Employing this more intimate diving approach has made him also a student of fish psychology, because after diving down over 20 meters, it is important to make even the most skittish of fish as comfortable as possible, to get the desired and often unique photograph. Sascha freely shares his tips and advice. Feel free to ask him!
For photography, Sascha has been fan of Olympus cameras starting his early digital work with several Olympus 5050Zs but has recently upgraded an Olympus Tough 5 (with housing). He only uses the camera’s internal flash rather than strobes, as they get in the way during freediving. At night, he uses a canister light, but knowing these photos were made by a free diver, dragging equipment around at night, in rough seas, you can appreciate his artistry as well as scientific approach.
Thank you Sascha for your huge contribution to Australasian Fishes!
This journal post was written by Australasian Fishes member, Harry Rosenthal.
Anotado en miércoles, 13 de septiembre de 2017 a las 02:54 AM por markmcg markmcg | 12 comentarios | Deja un comentario

06 de septiembre de 2017

Wanted: Images showing rapid colour change in goatfishes

For a study of the taxonomy of goatfishes, Franz Uiblein, a fish taxonomist from Norway, is looking for images that document colour changes in the Bluestriped Goatfish, Upeneichthys lineatus.
This may be by subsequent photographs (or video footage) taken of the same individual fish in situ, or from captive fish in aquaria. Franz is especially interested in images that show quick colour change of the tail-fin of individual fish, as this has been rarely documented, but may occur rather frequently.
Goatfishes are among those fish groups able to change colour considerably and this has puzzled many taxonomists. The amount of colour change is a very important (but perhaps underestimated) consideration in species identification.
Please upload as many of your goatfish images as you can to help Franz and his collaborators document colour change in goatfishes properly!
Anotado en miércoles, 06 de septiembre de 2017 a las 06:16 AM por markmcg markmcg | 4 comentarios | Deja un comentario

27 de septiembre de 2017

Fluffy makes a splash!

It's not every day that a White Shark washes up on a popular swimming beach in Sydney.
But that's what happened on the morning of 11 September 2017, when a 1.8m long juvenile White Shark 'beached' itself on the rocks at Manly Beach. One person tried several times unsuccessfully to push the shark back into the water. People from Sea Life Sanctuary arrived and transported the fish to the nearby ocean pool at Fairy Bower for observation. During this time a crowd of onlookers gathered and the shark was affectionately named "Fluffy".
Fluffy stayed in the pool under close observation for 5 hours before being moved to a tank at Sea Life Sanctuary. The following morning he was released 4km offshore. View video.
White Sharks occur worldwide in temperate, coastal waters, but are also known to swim into the tropics. In Australia, they have been recorded from southern Queensland, around the south of the country and north to north-western Western Australia.
Needless to say, Fluffy's appearance was big news. Here are just a few of the stories.
Australasian Fishes member, Nick Dawkins captured this terrific image from the edge of Fairy Bower pool by holding his camera below the surface. Nine more images are available in Nick's observation. Thank you Nick!
Anotado en miércoles, 27 de septiembre de 2017 a las 04:40 AM por markmcg markmcg | 15 comentarios | Deja un comentario

20 de septiembre de 2017

Slender Sunfish stranding

It must have been sad to watch but wow, what a story.
The photos above, plus another two (see links below), were taken by hylacola. They record a mass stranding of Slender Sunfish, Ranzania laevis, on 16 May 2014.
Interestingly, the southern coastline of Western Australia around Albany (Peaceful Bay to Bremer Bay) seems to be a hot spot for mass strandings of Slender Sunfish, with strandings documented in 1928 (Gomon et al., 2008), 1941, 2008 (with map), this record in 2014 and another in 2016 (view video).
One of my colleagues wondered if the fish were aggregating in shallow water to spawn. Smith, et al. (2010), however, stated that "Gonad development indicated spawning was not imminent. The cause of the strandings was unclear, although advection of fish to the south coast by the tropical Leeuwin Current was strongly implicated." In other words, the strong Leeuwin Current that flows down the coast of Western Australia may have swept the fish 'around the corner' of the State, then onto the southern coast.
The Slender Sunfish occurs globally in tropical and temperate seas. In Australian waters, it is known from tropical northern Queensland, right around the temperate south of the country and north to North West Cape, Western Australia.
Perhaps surprisingly, given its unusual shape, the Slender Sunfish is a strong swimmer. (View video)
References:
  1. Gomon, M.F., Bray, D. & R.H. Kuiter (Eds). 2008. The Fishes of Australia's Southern Coast. Reed New Holland. Pp. 928.
  2. Smith, K.A., Hammond, M. & P G. Close, 2010. Aggregation and stranding of elongate sunfish (Ranzania laevis) (Pisces:Molidae) (Pennant, 1776) on the southern coast of Western Australia. Journal of the Royal Society of Western Australia, 93: 181–188.
Anotado en miércoles, 20 de septiembre de 2017 a las 11:19 PM por markmcg markmcg | 3 comentarios | Deja un comentario