NEWSLETTER 11/2012 18. November 2012



  • André Afonso, CCMAR- Universidade do Algarve, Portugal
  • Joanna D. Borucinska, Department of Biology, University of Hartford, West Hartford, CT, USA
  • Bonnie Holmes, School of Biological Sciences, The University of Queensland, Australia
  • South East Queensland Tiger Shark Research (Homepage)




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Many thanks to:


NICK COBURN PHILLIPS, Explorer ~ Marine Scientist & Cameraman, Creator of BORNEO SHARKARMA for the images of Trygonorrhina dumerilii (CASTELNAU, 1873), the first record ot this species in Borneo!:



Joachim Seidel, Germany for the image of Carcharhinus longimanus (POEY, 1861):





Please send your images to shark-references!




Many thanks for sending missing papers:


Dipl.Ing. Lutz Andres

Oliver Landemaine  


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

Please support and send missing papers (not listed papers or papers without the infosymbol) to




New described species:




EHRET, D.J. & MACFADDEN, B.J. & JONES, D.S. & DEVRIES, T.J. & FOSTER, D.A. & SALAS-GISMONDI, R. (2012): Origin of the white shark Carcharodon (Lamniformes: Lamnidae) based on recalibration of the Upper Neogene Pisco Formation of Peru. Palaeontology, 55: 1139–1153 


New species: Carcharodon hubbelli

Abstract: The taxonomic origin of the white shark, Carcharodon, is a highly debated subject. New fossil evidence presented in this study suggests that the genus is derived from the broad-toothed ‘mako’, Carcharodon (Cosmopolitodus) hastalis, and includes the new species C. hubbelli sp. nov. – a taxon that demonstrates a transition between C. hastalis and Carcharodon carcharias. Specimens from the Pisco Formation clearly demonstrate an evolutionary mosaic of characters of both recent C. carcharias and fossil C. hastalis. Characters diagnostic to C. carcharias include the presence tooth serrations and a symmetrical first upper anterior tooth that is the largest in the tooth row, while those indicative of C. hastalis include a mesially slanted third anterior (intermediate) tooth. We also provide a recalibration of critical fossil horizons within the Pisco Formation, Peru using zircon U-Pb dating and strontium-ratio isotopic analysis. The recalibration of the absolute dates suggests that Carcharodon hubbelli sp. nov. is Late Miocene (6–8 Ma) in age. This research revises and elucidates lamnid shark evolution based on the calibration of the Neogene Pisco Formation.




BEHAN, C. & WALKEN, G. & CUNY, G. (2012): A carboniferous chondrichthyan assemblage from residues within a Triassic karst system at Cromhall quarry, Gloucestershire, England. Palaeontology, 55: 1245–1263 


New genus: Cromhallia

New species: Cromhallia parvunda

Abstract: Sixteen different Lower Carboniferous (Tournaisian Courceyan to Chadian age, Mississippian) chondrichthyan teeth types have been extracted from Triassic erosional/aeolian fills in shallow karst systems found in the limestone quarry at Cromhall, Gloucestershire, England. These Carboniferous teeth have been found within a much larger assemblage of disarticulated bones and teeth belonging to small late Triassic terrestrial reptiles, for which Cromhall quarry is famous. The Carboniferous teeth are derived fossils, released during subaerial dissolution of the surrounding limestones. Owing to low specimen numbers and uncertainty of intraspecific character, 10 types of teeth are left in open nomenclature, although it is likely they represent new taxa. They belong to Jalodus, Ctenacanthiformes, Protacrodus, Orodus, Chomatodus, Petalodontidae, Euchondrocephali?, Helodus and Psephodus. A new genus and species, Cromhallia parvunda, of indeterminate phylogenetic relationships, is also erected. The assemblage includes also an identified suite comprising Thrinacodus ferox, Bransonella cf. nebraskensis and Stethacanthus cf. altonensis. The identification of all fish teeth found in the Cromhall assemblages as derived fossils from the Carboniferous removes any ambiguity regarding the fully terrestrial nature of the late Triassic fauna preserved in the residue-bearing karst systems.






New Paper

Rezent Papers:

AFONSO, A.S. & HAZIN, F.H.V. & BARRETO, R.R. & SANTANA, F.M. & LESSA, R.P. 2012 Extraordinary growth in tiger sharks Galeocerdo cuvier from the South Atlantic Ocean. Journal of Fish Biology, in press

AFONSO, A.S. & SANTIAGO, R. & HAZIN, H. & HAZIN, F.H.V.  2012 Shark bycatch and mortality and hook bite-offs in pelagic longlines: Interactions between hook types and leader materials. Fisheries Research, 131-133: 9-14

AGNESE, M. & ROSATI, L. & MURIANO, F. & VALIANTE, S. & LAFORGIA, V. & ANDREUCCETTI, P. & PRISCO, M. 2012 Expression of VIP and its Receptors in the Testis of the Spotted Ray Torpedo marmorata (Risso 1880). Journal of Molecular Neuroscience, 48 (3): 638-646

ANDRADES, R. & PINHEIRO, H.T. & SANTOS, R.G. & MARTINS, A.S. & COSTA, P.A.S. 2012 A new record of whale shark Rhincodon typus in Brazilian waters: a report of association with Caranx crysos. Journal of Fish Biology, in press

BARBINI, S.A. & LUCIFORA, L.O. 2012 Ontogenetic diet shifts and food partitioning between two small sympatric skates (Chondrichthyes, Rajidae) in the Southwestern Atlantic. Marine and Freshwater Research, 63 (10): 905-913

BORUCINSKA, J.D. & CIELOCHA, J.J. & JENSEN, K. 2012 The parasite-host interface in the zonetail butterfly ray Gymnura zonura, infected with Hexacanalis folifer (Cestoda: Lecanicephalidea). Journal of Fish Diseases, 35: in press

BORUCINSKA, J.D. & OBASA, O.A. & HAFFEY, N.M. & SCOTT, J.P. & WILLIAMS, L.N. & BAKER, S.M. & MIN, S.J. & KAPLAN, A. & MUDIMALA, R. 2012 Morphological features of coronary arteries and lesions in hearts from five species of sharks collected from the northwestern Atlantic Ocean. Journal of Fish Diseases, 35 (10): 741-754

CARRERA, I. & ANADÓN, R. & RODRIGUEZ-MOLDES, I. 2012 Development of tyrosine hydroxylase-immunoreactive cell populations and fiber pathways in the brain of the dogfish Scyliorhinus canicula: New perspectives on the evolution of the vertebrate catecholaminergic system. Journal of Comparative Neurology, 520 (16): 3574-3603

CLARKE, S.C. & HARLEY, S.J. & HOYLE, S.D. & RICE, J.S. 2012 Population Trends in Pacific Oceanic Sharks and the Utility of Regulations on Shark Finning. Conservation Biology, in press

DICKEN, M.L. & SMALE, M.J. & BOOTH, A.J. 2012 Long-term catch and effort trends in Eastern Cape Angling Week competitions. African Journal of Marine Science, 34 (2): 259-268

DOMINGO, A. & PONS, M. & JIMÉNEZ, S. & MILLER, P. & BARCELÓ, C. & SWIMMER, Y. 2012 Circle Hook Performance in the Uruguayan Pelagic Longline Fishery . Bulletin of Marine Science, 88 (3): 499-511

D'ONGHIA, G. & MAIORANO, P. & CARLUCCI, R. & CAPEZZUTO, F. & CARLUCCIO, A. & TURSI, A. & SION, L. 2012 Comparing Deep-Sea Fish Fauna between Coral and Non-Coral "Megahabitats" in the Santa Maria di Leuca Cold-Water Coral Province (Mediterranean Sea). PLoS One, 7 (9): e44509

FISK, A.T. & LYDERSEN, C. & KOVACS, K.M. 2012 Archival pop-off tag tracking of Greenland sharks Somniosus microcephalus in the High Arctic waters of Svalbard, Norway. Marine Ecology Progress Series, 468: 255-265

FOSTER, D.G. & EPPERLY, S.P. & SHAH, A.K. & WATSON, J.W. 2012 Evaluation of Hook and Bait Type on the Catch Rates in the Western North Atlantic Ocean Pelagic Longline Fishery. Bulletin of Marine Science, 88 (3): 529-545

HOLLENSEAD, L. 2012 Monitoring movement patterns of juvenile smalltooth sawfish (Pristis pectinata) using acoustic monitoring and tracking in a nursery habitat in Southwest Florida. MS thesis, The Florida State University, 119pp

HOLMES, B.J. & SUMPTON, W.D. & MAYER, D.G. & TIBBETTS, I.R. & NEIL, D.T. & BENNETT, M.B. 2012 Declining trends in annual catch rates of the tiger shark (Galeocerdo cuvier) in Queensland, Australia. Fisheries Research, 129-130: 38-45

HSIAO, S.-T. & HSU, C. –H. & LIU, D.-C. & CHEN, I.-S. 2012 The Complete Mitochondrial DNA Sequence of the Deepwater Stingray Plesiobatis daviesi (Wallace, 1967): Unique Features in the Mitochondrial D-loop Region. Journal of Taiwan Fisheries Research, 20 (1): 1-16

JACOBY, D.M.P. & SIMS, D.W. & CROFT, D.P. 2012 The effect of familiarity on aggregation and social behaviour in juvenile small spotted catsharks Scyliorhinus canicula. Journal of Fish Biology, 81 (5): 1596-1610

JENNINGS, D.E. & DIBATTISTA, J.D. & STUMP, K.L. & HUSSEY, N.E. & FRANKS, B.R. & GRUBBS, R.D. & GRUBER, S.H. 2012 Assessment of the aquatic biodiversity of a threatened coastal lagoon at Bimini, Bahamas. Journal of Coastal Conservation, 16 (3): 405-428

KEARN, G.C. & WHITTINGTON, I.D. & THOMAS, P. 2012 A new species of Asthenocotyle Robinson, 1961 (Monogenea: Microbothriidae), a skin parasite of the great lanternshark Etmopterus princeps Collett from the Azores, with a redescription of A. kaikourensis Robinson, 1961 and observations on A. taranakiensis Beverley-Burton, Klassen & Lester, 1987. Systematic Parasitology, 83 (2): 145-158

MAIA, C. & ERZINI, K. & SERRA-PEREIRA, B. & FIGUEIREDO, I. 2012 Reproductive biology of cuckoo ray Leucoraja naevus. Journal of Fish Biology, 81 (4): 1285-1296

MANIRE, C.A. & CLARKE, A.C. & WERT, D. & LANDOLFI, J. 2012 Lymphosarcoma in a captive bonnethead shark, Sphyrna tiburo (L.). Journal of Fish Diseases, 35: in press

MASSON, A.A. & ORMONDE DO CARMO, P.H.A. & CARVALHO, J.L.V. 2012 Rhabdomyolysis secondary to an accident with marine stingray (Dasyatis family). Journal of Venomous Animals and Toxins Including Tropical Diseases, 18 (3): 344-348

MCCAULEY, D.J. & YOUNG, H.S. & DUNBAR, R.B. & ESTES, J.A. & SEMMENS, B.X. & MICHEL, F. 2012 Assessing the effects of large mobile predators on ecosystem connectivity. Ecological Applications, 22 (6): 1711-1717

MCMEANS, B.C. & ARTS, M.T. & FISK, A.T. 2012 Similarity between predator and prey fatty acid profiles is tissue dependent in Greenland sharks (Somniosus microcephalus): Implications for diet reconstruction. Journal of Experimental Marine Biology and Ecology, 429: 55-63

MIZUSAWA, K. & AMIYA, N. & YAMAGUCHI, Y. & TAKABE, S. & AMANO, M. & BREVES, J.P. & FOX, B.K. & GRAU, E.G. & HYODO, S. & TAKAHASHI, A. 2012 Identification of mRNAs coding for mammalian-type melanin-concentrating hormone and its receptors in the scalloped hammerhead shark Sphyrna lewini. General and Comparative Endocrinology, 179 (1): 78-87

MOURIER, J. 2012 Manta rays in the Marquesas Islands: first records of Manta birostris in French Polynesia and most easterly location of Manta alfredi in the Pacific Ocean, with notes on their distribution. Journal of Fish Biology, in press

MOURIER, J. & PLANES, S. 2012 Direct genetic evidence for reproductive philopatry and associated fine-scale migrations in female blacktip reef sharks (Carcharhinus melanopterus) in French Polynesia. Molecular Ecology, in press

MOURIER, J. & PLANES, S. & BURAY, N. 2012 Trophic interactions at the top of the coral reef food chain. Coral Reefs, in press

MUTER, B.A. & GORE, M.L. & GLEDHILL, K.S. & LAMONT, C. & HUVENEERS, C. 2012 Australian and U.S. News Media Portrayal of Sharks and Their Conservation Conservation Biology, in press

RÁBAGO-QUIROZ, C.H. & LÓPEZ-MARTÍNEZ, J. & VALDEZ-HOLGUÍN, J.E. & NEVÁREZ-MARTÍNEZ, M.O. & ACEVEDO-CERVANTES, A. 2012 Fish assemblages in the bycatch of bottom shrimp trawls on the west side of the Gulf of California, Mexico. Marine Biology Research, 8 (9): 865-876

REINICK, C.L. & LIANG, L. & ANGLESON, J.K. & DORES, R.M. 2012 Identification of an MRAP-Independent Melanocortin-2 Receptor: Functional Expression of the Cartilaginous Fish, Callorhinchus milii, Melanocortin-2 Receptor in CHO Cells. Endocrinology, 153 (10): 4757-4765

SAEZ, S. & PEQUEÑO, G. & LAMILLA, J. 2012 Clave taxonómica del Superorden Squalomorphi de Chile (Pisces: Elasmobranchii). (Taxonomic keys based on the morphology of the caudal fin, for the sharks identification (Chondrichthyes; Elasmobranchii) from the Chilean coasts.) Revista de Biología Marina y Oceanografía, 47 (2): 245-256

SAJEEVAN, M.K. & SANADI, R.B. 2012 Diversity, distribution and abundance of oceanic resources around Andaman and Nicobar Islands. Indian Journal of Fisheries, 59 (2): 63-67

SANJUAN, A. & DE CARLOS, A. & RODRIGUEZ-CABELLO, C. & BAÑON, R. & SANCHEZ, F. & SERRANO, A. 2012 Molecular identification of the arrowhead dogfish Deania profundorum (Centrophoridae) from the northern waters of the Iberian peninsula. Marine Biology Research, 8 (9): 901-905

SCHARER, R.M. & PATTERSON, W.F. & CARLSON, J.K. & POULAKIS, G.R. 2012 Age and Growth of Endangered Smalltooth Sawfish (Pristis pectinata) Verified with LA-ICP-MS Analysis of Vertebrae. PLoS ONE, 7 (10): e47850

SEGURA, A.M. & TRINCHIN, R. & RABELLINO, J. & SCARABINO, F. & TEIXEIRA-DE MELLO, F. & CARRANZA, A. 2012 Length-weight relationships of 14 coastal fish species from Punta del Diablo (Rocha, Uruguay). Journal of Applied Ichthyology, 28 (5): 852-853

TAVARES, R. & ORTIZ, M. & AROCHA, F. 2012 Population structure, distribution and relative abundance of the blue shark (Prionace glauca) in the Caribbean Sea and adjacent waters of the North Atlantic. Fisheries Research, 129-130: 137-152

THEISS, S.M. & COLLIN, S.P. & HART, N.S. 2012 Morphology and spatial arrangement of the mechanosensory lateral line system in wobbegong sharks. Abstract Zoomorphology, 131 (4): 339-348

VELTE, F. 2012 Aquarienbeobachtungen zum Putzverhältnis zwischen dem Lippfisch Labroides dimidiatus und dem Braungebänderten Bambushai (Chiloscyllium punctatum). Abstract. In: Abstractband 9. Tagung der Gesellschaft für Ichthyologie e.V. (GFI), 28.-30.  September 2012 in Düsseldorf: 34-35


WEARMOUTH, V.J. & SOUTHALL, E.J. & MORRITT, D. & THOMPSON, R.C. & CUTHILL, I.C. & PARTRIDGE, J.C. & SIMS, D.W. 2012 Year-round sexual harassment as a behavioral mediator of vertebrate population dynamics. Ecological Monographs, 82 (3): 351-366 




BEHAN, C. & WALKEN, G. & CUNY, G. 2012 A carboniferous chondrichthyan assemblage from residues within a Triassic karst system at Cromhall quarry, Gloucestershire, England. Palaeontology, 55: 1245–1263

EHRET, D.J. & MACFADDEN, B.J. & JONES, D.S. & DEVRIES, T.J. & FOSTER, D.A. & SALAS-GISMONDI, R. 2012 Origin of the white shark Carcharodon (Lamniformes: Lamnidae) based on recalibration of the Upper Neogene Pisco Formation of Peru. Palaeontology, 55: 1139–1153

PAWELLEK, T. & ADNET, S. & CAPPETTA, H. & METAIS, E. & SALEM, M. & BRUNET, M. & JAEGER. J.-J. 2012 Discovery of an earliest Pliocene relic tropical fish fauna in a newly detected cliff section (Sabratah Basin, NW Libya). Neues Jahrbuch für Geologie und Palaontologie, Abhandlungen, 266: 93-114

SIVERSON, M. & WARD, D.J. & LINDGREN, J. & KELLEY, L.S. 2012 Mid-Cretaceous Cretoxyrhina (Elasmobranchii) from Mangyshlak, Kazakhstan and Texas, USA. Alcheringa, in press (18pp)

TIWARI, R.P. & RALTE, V.Z. 2012 Fossil batoid and teleost fish remains from Bhuban Formation (Lower to Middle Miocene), Surma Group, Aizawl, Mizoram. Current Science, 103 (6): 716-720







New ancient shark species gives insight into origin of great white

Filed under ResearchSciences on Wednesday, November 14, 2012.

GAINESVILLE, Fla. — The great white shark is one of the largest living predatory animals and a magnet for media sensationalism, yet its evolutionary history is as misunderstood as its role as a menace.

Originally classified as a direct relative of megatooth sharks, the white shark’s evolutionary history has been debated by paleontologists for the last 150 years. In a study appearing in print and online today in the journal Palaeontology, University of Florida researchers name and describe an ancient intermediate form of the white shark, Carcharodon hubbelli, which shows the modern white shark likely descended from broad-toothed mako sharks. The study deviates from the white shark’s original classification as a relative of megatooth sharks such as the extinct Carcharocles megalodon, the largest carnivorous shark that ever lived.

Based on recalibrated dates of the excavation site in Peru, the study also concludes the new species was about 2 million years older than previously believed.

“We can look at white sharks today a little bit differently ecologically if we know that they come from a mako shark ancestor,” said lead author Dana Ehret, a lecturer at Monmouth University in New Jersey who conducted research for the study as a UF graduate student. “That 2-million-year pushback is pretty significant because in the evolutionary history of white sharks, that puts this species in a more appropriate time category to be ancestral or kind of an intermediate form of white shark.”

Most ancient shark species are named using isolated teeth, but analysis of C. hubbelli, also known as Hubbell’s white shark, was based on a complete set of jaws with 222 teeth intact and 45 vertebrae. The species was named for Gainesville resident Gordon Hubbell, a collector who recovered the fossils from a farmer who discovered them in the Pisco Formation of southern Peru in 1988. Hubbell donated the specimens to the Florida Museum of Natural History on the UF campus in December 2009.

“The impetus of this project was really the fact that Gordon Hubbell donated a majority of his fossil shark collection to the Florida Museum,” Ehret said. “Naming the shark in his honor is a small tip of the hat to all the great things he has done to advance paleontology.”

Ehret and co-authors published an initial study describing the shark specimens in the Journal of Vertebrate Paleontology in 2009, but dates for the site reflected information from a 1985 study about the Pisco Formation, he said. With Hubbell’s hand-drawn maps and descriptions of the landscape, researchers returned to the site and found the exact spot the fossils were discovered.

Scientists extracted more accurate age estimates from mollusk shells in the fossil horizon to determine the shark species was from the late Miocene, about 6.5 million years ago, rather than the early Pliocene, about 4.5 million years ago. The new dates will also be useful for better understanding other fossils found in the rich Pisco Formation, which include new whale, marine sloth and terrestrial vertebrate species.

“The thing that was remarkable to me was that these fossils came from right out in the desert and this was before GPS, so Dana had only an approximate notion of where it was,” said Florida Museum of Natural History Director Douglas Jones, a study co-author who conducted strontium isotope dating of the fossils. “But after a few days of looking, we were able to find this deposit and Dana found the rest of the missing shark’s teeth.”

Researchers determined Hubbell’s white shark was related to ancient broad-toothed mako sharks by comparing the physical shapes of shark teeth to one another. While modern white sharks have serrations on their teeth for consuming marine mammals, mako sharks do not have serrations because they primarily feed on fish. Hubbell’s white shark has coarse serrations indicative of a transition from broad-toothed mako sharks to modern white sharks.

These evolutionary relationships have been hypothesized for decades, and researchers who interpret modern white sharks as being more closely related to megatooth sharks say it is “a friendly disagreement,” according to Michael Gottfried, an associate professor in geological sciences at Michigan State University.

But shark expert David Ward, a research associate at the Natural History Museum, London, said “fewer people believe the big megatooth sharks are related to the great white sharks than believe the Earth is flat.”

“Everyone working within the field will be absolutely delighted to see this relationship formalized,” Ward said.

Study co-authors include Bruce MacFadden of the Florida Museum, Thomas DeVries of the Burke Museum of Natural History and Culture in Seattle, David Foster of UF and Rodolfo Salas-Gismondi of Museo de Historia Natural Javier Prado in Lima.


This well-preserved fossil is the only intact partial skull ever found of a white shark that lived about 4.5 million years ago. In a new University of Florida study appearing in the Nov. 14, 2012, issue of Palaeontology, the species was named Carcharodon hubbelli for Gordon Hubbell, who donated the fossil to the Florida Museum of Natural History on the UF campus. The fossil jaw contains 222 teeth, some in rows up to six teeth deep.

(Jeff Gage/Florida Museum of Natural History)
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Danielle Torrent,
Dana Ehret,, 352-871-7944





New Tagging Research Reveals Remarkable Mako Shark Round-Trip Journey in High Resolution

by Outdoor Hub on October 29, 2012

submitted by: Guy Harvey Research Institute


New Tagging Research Reveals Remarkable Mako Shark Round-Trip Journey in High Resolution

A satellite reporting tagging device know as a SPOT tag, attached to a shortfin mako shark dubbed “Carol” in New Zealand five months ago, is providing scientists with remarkable and previously unknown details of the timing and long-distance migratory movements of this species.

The Guy Harvey Research Institute (GHRI) at Nova Southeastern University is collaborating with the New Zealand National Institute of Water and Atmospheric Research (NIWA) on the tagging experiment with Carol the shortfin mako shark.

The SPOT tag is revealing that Carol is spending a lot of time at the oceans surface, reporting her location to the satellite several times daily.

“The unexpectedly frequent daily detections are providing us with a really high resolution view of the migration of this animal,” said GHRI Director Dr. Mahmood Shivji. “We”ve found that Carol has traveled over 5,700 miles in five months, averaging 60 miles per day during some parts of her migration–and this is just a juvenile shark!”

To follow Carol’s travels on a GHRI interactive website go to:

“Conventional identification tags tell us little about the timing of mako shark movements, the route that they take or distance traveled,” said Dr.

Malcolm Francis, who is leading the NIWA effort on this study.  “The SPOT tag, revealing Carol’s detailed travels from New Zealand to Fiji and back, shows theses sharks have an amazing internal navigation system that keeps them on course over long journeys.”

Given the high fishing pressure on makos for their fins and meat, this species is showing declining population trends in parts of its range, which has resulted in the species being listed as “Vulnerable” on the IUCN Red List of threatened species.

Based on the amazing results from this initial trial, the GHRI and NIWA are expanding their mako migration study off New Zealand starting in January 2013, according to Dr. Shivji. The GHRI and Dr. Guy Harvey are also working with Captain Anthony Mendillo of Keen M International to compare the migratory patterns of mako sharks in the Atlantic by tagging them off the coast of Isla Mujeres, Mexico.

Image courtesy Scott Tindale/Guy Harvey Research Institute





Whale sharks regulate their body temperature

By  Paul Robinson - 17 Oct 2012 13:29:0 GMT
Whale sharks regulate their body temperature


Whale shark image; Credit: © Shutterstock


Marine fish often visit the surface to warm up after diving deep. 4 whale sharks "volunteered" to test some time/depth recorders for Michelle Thums of the University of Western Australia and her colleagues. They publish their research paper, Evidence for behavioural thermoregulation by the world's largest fish, in Biology Letters today.

Vertical movement like this has not often been studied, despite its importance for aquatic animals. Air-breathers have an obvious affinity for the surface but it's a surprise to find many gill-breathers curiously similar. Thermal recovery is certainly the most obvious cause for such behaviour.

With negative buoyancy, most pelagic fish species swim towards the surface quite often, but elasmobranchs (eg. sharks and rays) spend long periods at the surface following dives. Rhincodon typus, the whale shark is the world's biggest fish and spends an average of 49% of its time at the surface between its diving stints (of over 1000 metres). Analysing the dives resulted in the discovery of three dive-types.

1. From 0400 to 1600 hours was the commonest dive-type, occupying 44% of the animal's diving behaviour

2. From 1800 to 0600 hours, type 2 dives were almost as common as type 1.

3. From 0300 to 1800 hours, with peaks at 0500 and 1200h, type 3 dive bouts had the longest post-dive surface duration. A shark at Christmas Island was used for a longer period and illustrated more type 3 dives than others over 88 days. This shark travelled to Indonesia during this time, using deeper waters up to 3482m at least! However the other individuals had a maximum of 9% of their diving as type 3. Individual preferences could have had something to do with these dives.

Results supported the idea that thermoregulation took place by using warm surface waters as a heater for the body. Fish physiology demands these higher body temperatures for optimal performance. In warm waters, above 25°C, no relationship exited and it's perhaps necessary to get rid of excess heat at some temperatures by diving deep to cooler water. It wouldn't have been ethical but measuring internal temperatures would have been useful, despite the fact that whale sharks are pure ectotherms. The external sensors should have indicated both ocean temperature and the approximate body temperature, especially after time at depth.

Overall, the research indicated a positive correlation between time spend at the surface and depth of dives at temperatures below 25°C. Other factors such as feeding, especially for a filter feeder, come into play. This animal however, recycles so much water that it would need to replace lost heat energy after a deep feeding "bout." More fish and especially large, non-filter-feeders could be usefully tagged now that this technology has been successfully employed. We look forward to the discovery of more intriguing information on our fish and other species.