NEWSLETTER 04/2013 21. April 2013

NEW PARTNERS:

• Jan Adolfssen, Natural History Museum of Denmark, Copenhagen University, Copenhagen, Denmark
• Enrique Bernárdez, Universidad de Atacama, Departamento de Geología, Copiapó, Atacama, Chile

         Partner in Google-Maps:                           

New images at shark-references:

• Bernhard Beaury, Germany: Echinorhinus schoenfeldi PFEIL, 1983, collection Bernhard Beaury, Galongraben near Siegsdorf, Bavaria
  
• Helmut Bracher, Germany: Echinorhinus pfauntschi PFEIL, 1983, Walbertsweiler, Germany
  
• Richard Chandler, USA: Echinorhinus blakei AGASSIZ, 1856; Beaufort County, Miocene,  Size: 0.4" 
  
• Patrick De Cock, Belgium: Echinorhinus priscus ARAMBOURG, 1952, Marroko, Ypresien, Qued Zem
  
• Marco Gulotta, Virginia, U.S.A.: Echinorhinus australis (CHAPMAN, 1909), Albian, Toolebuc Formation, Queensland, Australia
  
• Rodrigo Otero, Chile and Mario E. Suárez, Chile: Echinorhinus sp.; Algarrobo, San Antonio Province, Región de Valparaíso, Chile; Quebrada Municipalidad Strata (Niv. 9), Cretaceous, Maastrichtian, 3 teeth (SGO-PV-6630-6632);
  
• Al Mannering & Norton Hiller, New Zealand: Pseudoechinorhinus mackinnoni Pfeil, 1983
  
• Henri Cappetta, France: Gibbechinorhinus lewyi CAPPETTA, 1990
  
• Fundación SQUALUS http://www.squalus.org/: Paratrygon aiereba (MÜLLER & HENLE, 1841), first record Bita River, Orinoco Basin of Colombia
  
• Samuel Paco Iglésias, France: Apristurus nakayai IGLÉSIAS, 2012, holotype MNHN 2003-1983, adult male, 676 mm TL, Scale bars = 5 cm, e.g.:
  
   

Missing papers:

Many thanks to all friends of shark-references, who send me some missing paper last month!

Shark-References would kindly like to ask you for your contribution to this project.

Please support www.shark-references.com and send missing papers (not listed papers or papers without the infosymbol) to juergen.pollerspoeck@shark-references.com.
 

News from shark-references and partner:

Thanks a lot to Simon Weigman, University of Hamburg, Germany, for the species description of Planonasus parini at shark-references!

You want support shark-references and could write or update a species description (extanct/extinct sharks, skates, rays and chimaeras, parasites)? Please contanct me (juergen.pollerspoeck@shark-references.com)!

A review of the fossil Echinorhinidae (species descriptions, distribution)

Species:

New described species/Taxonomic News:

Recent:

Fossil:

Parasitology:

New Paper

Recent Papers:

Parasitology:

Fossil:

MISCELLANEOUS:

source: http://www.sciencedaily.com/releases/2013/04/130410141530.htm
 

Great white sharks gorge on dead whale blubber

Apr. 10, 2013 — Many terrestrial animals are frequently observed scavenging on other animals- whether it is a hyena stealing a lion kill in the Serengeti or a buzzard swooping down on a dead animal. However, documenting this sort of activity in the oceans is especially difficult, and often overlooked in marine food web studies.

Carcharodon carcharias) scavenging on whales and its potential role in further shaping the ecology of an apex predator," Captain Chris Fallows from Apex Expeditions collaborated with University of Miami (UM) scientists Dr. Neil Hammerschlag and Austin Gallagher, to explore the behaviors of Great white sharks scavenging on dead whales in South Africa. The team documented as many as 40 different sharks scavenging on a carcass over the course of a single day, revealing unique social interactions among sharks.

The study summarized observations based on four scavenging events opportunistically observed over a 10 year period. In each multi-day observation, the team recorded daily evidence of social, aggregative and feeding behaviors observed in the waters off South Africa. They suggest that although the occurrence of coming upon a whale carcass may be sporadic, the shark populations are likely prepared to scavenge on them, and may even rely on their scavenging activities to supplement their regular feeding activities.

"Although rarely seen, we suspect that as white sharks mature, scavenging on whales becomes more prevalent and significant to these species than previously thought," said Hammerschlag, who is director of the R.J. Dunlap Marine Conservation Program at UM.

The team found that sharks showed a clear preference for scavenging on the blubber, probably because these high calorie meals can sustain the sharks for longer periods of time. Interestingly, though, the study also found that sharks showed an initial preference for feeding on the whale's fluke before moving on to feed on the rest of the carcass. The team also found that while scavenging on whales, they ceased hunting and feeding on seals, one of their primary natural prey.

"While scavenging on the whale, the sharks clearly showed a size-based pecking order," said Fallows. "The biggest sharks came right in, targeting areas of highest blubber content, while smaller sharks fed on areas with less blubber or kept their distance from the whale, mostly scavenging on pieces of blubber that drifted away from the carcass."

The paper reveals how the social and size structure of sharks at the carcass appeared to be influenced by environmental patterns. "The cues, such as the oils, emanating from this pulse of food are likely attracting much larger sharks over 4.5 meters from long distances to scavenge," said Gallagher. "These data provide some credence to the hypothesis that large white sharks may be swimming known ocean corridors looking for dead, dying, or vulnerable whales."

"By attracting many large white sharks together to scavenge, we suspect that the appearance of a whale carcass can play a role in shaping the behaviors, movements, and the ecosystem impacts of white sharks" said Hammerschlag. "These patterns may shed some light into the ecology of this often studied -- yet still highly enigmatic -- marine predator."

 

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Journal Reference:

1. Chris Fallows, Austin J. Gallagher, Neil Hammerschlag.White Sharks (Carcharodon carcharias) Scavenging on Whales and Its Potential Role in Further Shaping the Ecology of an Apex Predator. PLoS ONE, 2013; 8 (4): e60797 DOI: 10.1371/journal.pone.0060797

 

enlarge

Scientists have explored the behaviors of Great white sharks scavenging on dead whales in South Africa. (Credit: Image courtesy of University of Miami)

source: http://www.sciencedaily.com/

Shark Tooth Weapons Reveal Missing Shark Species in Central Pacific Islands

Apr. 3, 2013 — The Gilbert Island reefs in the Central Pacific were once home to two species of sharks not previously reported in historic records or contemporary studies. The species were discovered in a new analysis of weapons made from shark teeth and used by 19th century islanders, reported in a study published April 3 in the open access journalPLOS ONE by Joshua Drew from Columbia University and colleagues from the Field Museum of Natural History.

Sharks were culturally important to the Gilbertese Islanders; historic records indicate a complex ritual system surrounding shark fishing and making fishing gear and weapons from shark teeth. For the current study, the researchers analyzed a collection of 120 of these weapons from the Field Museum of Natural History, including some that resemble clubs, daggers, lances, spears and swords. They identified eight species of sharks based on the teeth used in these weapons, two of which have never been reported from these waters, in either historical surveys or contemporary analysis. Both these species are currently common in other areas, so while it is possible that these species may still be living undiscovered in the GIlberts, it is more likely that the local populations have been driven to extinction.