SHARKS, SKATES, RAYS, AND CHIMAERAS UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE BUREAU OF COMMERCIAL FISHERIES Circular 228 TABLE 1. -- tiximum sizes of camnon species of sharks Species Traditional Mucimum length Muimum length maximum size (measure<l--U. S. coa.ts) (recorde<l--world) Scientific na.rr;e from literature SixgL. st.ark .... 1 Hexanchus sp. .•..•••••••. 15 feet 5 inches 26 feet 5 inches nd hary... ..... Carcharias taurus... 10 feet 5 inches 12 feet 3 inches 15 feet 11 inches Porbeagle •....... 1 LamTUl TUlSUS........... ... 10 feet 12 feet 12 feet Sall10n shark. .... LamTUl ditropis . 8 feet 6 inches 8 feet 6 inches 12 feet L 0 .•.••.•.•.... Isurus oxyrinchus ...... ... 10 feet 6 inches 12 feet 12 feet - 13 feet 'hi te sr.ark. ..... Carcharodan carcharias. 18 feet 2 inches 21 feet 36 feet 6 inches Basking shar".... Cetorhinus maximus . 32 feet 2 inches 45 feet 40 feet - 50 feet Thresher shark... Alopias vulpinus . 18 feet 18 feet 20 feet rse shark...... Ginglymostoma cirraturn.. 9 feet 3 inches 14 feet Whale shark. ..... Rhincodan typus........ .•. 38 feet 45 feet 45 feet - 50 feet Olain dogfish.... Scyliorhinus retifer. ... .. 1 foot 5 inches 2 feet 6 inches Leopard shark.... Triakis semifasciata... 5 feet 5 feet Smooth dogfish ... Alustelus canis ......... ... 4 feet 9 inches 5 feet rieer shark...... Galeocerdo cuvieri..... ... 13 feet 10 inches 18 feet 30 feet Soupfin shark.... Galeorhinus zyopterus . .. 6 feet 5 inches 6 feet 5 inches 6 feet 5 inches Blue shark. ...... Prionace glauca ....... 11 feet 12 feet 7 inches 25 feet Bul .. shark. ...... Carcharhinus leucas. .. 9 feet 10 inches 10 feet Whi tetip shark. .. Carcharhmus longimanus .. 11 feet 6 inches 12 feet Sandbar shark.... Caycharhinus milberti. .. 7 feet 8 inches 8 feet Dusky soork...... Carcharhinus obscurus . 11 feet 11 inches 15 feet Bonn thead.. ..... phyrTUl ttburo . .. 3 feet 7 inches 6 feet Cr at hrum.erhead . Sphyrna mokarran ..... 18 feet 4 inches 15 feet iny 0 fish.... Squalus acanthias ...... ... 5 feet 3 inches 5 feet I I n d fish .... 1 Etmopterus virens... .. ... 0 feet 11 inches I ~d at r d fish. Squaliolus ep ••...••...•.. 0 feet 7 inches nland shar .. Sommosus microcephalus. 16 feet 6 inches 21 feet 24 feet r ......... 1 PrtStiophorus schroederi . 2 feet 10 inches shark .••... , Squatrna dumerill ........ 4 feet 5 inches UNITED STATES DEPARTMENT OF THE INTERIOR Stewart L. Udall, Secretary Johll A. Carver, Jr., Under Secretary Stallley A. CHin, Assistant Secretary jor F~sh and Wildlife FISH AND WILDLIFE SERVICE, Clarence F. Pautzke, Commissioner BUREAU OF COMMERCIAL F:SHERIES, Donald L. McKernan, Director Sharks, Skates, Ray, and Chimaeras By J. R. Thompson Stewart Springer Circular ll8 Washington, D.C. September 1965 CONTENTS Page Introduction.. .... ............................................................................ 1 Class Chondrichthyes, the cartilaginous fishes..................................... 2 Sharks..... ........ .. ............... ............................................................ 4 Skates and rays...................... ...... ............................................... .... 10 Chimaeras ............................................................. ....................... 14 Annotated list of references. ............................................................. 16 ILLUSTRATIONS "Family tree" of the vertebrates illustrating, in the opinion of many zo- ologists, the relations existing among member s of the group............. 2 A great hammerhead from the Gulf of Mexico and her litter. Few sharks produce this many young at one .. ime............. .... ............................ 4 A "typ1cal" shark, l11ustrating terms used in description....................... 5 Top: A small spiny dogfish shark, Squalus cubensis, from the Gulf of Mexico. Many species of sharks are many times smaller than this species. Bottom: A large Silky shark, Eulamia floridana, taken on a tuna longline. These large, oceanic sharks sometimes reach lengths of about 10 feet......... ...... .... ..................... .......................... ... .... 6 A small thresher shark, Alopias vulpinus. A 14-foot specimen of this species, recently taken was estimated to weigh aPfroximately 500 pounds and possessed a caudal lobe measuring 7z feet. The long caudal lobe 1S apparently used to stun prey.................................... 9 Removing the liver from a large silky shark.. ....... ... ........... ...... ..... 10 A generalized skate illustrating terms used in descnption...................... 11 A "typical" ray, the roughtail stingray, Dasyatis centroura. This specUne.n measured 62 inches across the fins and weighed 285 pounds. Such rays are taken frequently in trawl drags along the east coast of the United States...................................................................................... 13 A generalized chimaera illustrating terms used in description................ 14 iii SHARKS, RAYS, SKATES, AND CHIMAERAS By J. R. Thompson and Stewart Springer INTRODUCTION Sharks, skates, rays, and, to a require special collecting and handling lesser extent, chimaeras--all grouped techniques. They are diificult to keep in by zoologists in the single vertebrate captivity, and their collection and study class Chondrichthyes (cartilaginous as living animals is quite expensive. fishes)--have been the subjects of in­ But over the years, zoologists have tere st for many year s . On the negative succeeded in amas sing sufficient data side, the interest in many of these to outline, in greater or les ser detail, fishes has arisen largely from fear-­ the characteris~ic s and habits of many fear of injury to fishermen and of the cartilaginous fishes . swimmer s, fear of damage to fishing gear and equipment, and the fear that This paper has been written as an is a natural accompaniment of a lack of introduction to the members of the class knowledge. On the positive side, the Chondrichthyes . The information con­ interest has arisen as a result of at­ tained has been drawn from the litera­ tempts to turn some of these fishes ture, from zoologists and fishermen of to economic advantage, and out of man's many countries, and from the personal innate curiosity concerning the world experiences and observations of the around hlm. authors . The purpose of the paper is to answer the man y general questions Despite widespread lnterest, ac­ asked fishery z oologists each year cumulation of adequate knowledge con­ concerning sharks, skates, rays, and cermng sharks and theIr close relatives chimaeras, o r if not to a nswer, at has been slow, and a large body of least to suggest further, m o re detailed speculation and "old wives' tales" has sources of information. Toward this arisen as a result of attempts to £111 end, the text has been kept brief and in the gaps . Obstacles to the study of general, and an annotated list of ref­ cartilaglnous fishe s are many. Most erences has been included. In most of these fishes are pelagic, and many cases, the r e ader who is sufficiently of them inhabit the open water s of the interested to pursue the subject beyond high seas where large ocean-going the confines of this circular will find vessels are needed for their study. more material in the references listed. Many species are confined to relatively He may also find clues to further re­ great depths where collection is dif­ search sources in the bibliographies ficult and expensive. Even those species contained in the references examined. that inhabit shallower, coastal water s To facilitate use, the references are listed by topic in an arrangement Note.--J. R. TIlOmpson. Fishery Biologist(Research). roughly paralleling the arrangement Bureau of Commercial Fisheries Exploratory Fishing Base. Pascagoula. Miss •• and Stewart Springer. Fishery Biologist of the subhec1dings of the text. (Research). Bureau of Commercial Fisheries Ichthyological Field Station. Stanford. Calif. Terms commonly applied to car­ tilaginous fishes and other large marine 1 creatures are frequently subject to the Greek words elasmo, mea n i n g confusion. Scientific names of Greek platelike or s 1 it 1 ike, and branchia, or Latin derivation are frequently re­ meaning gill) which has corne into duced to English form and used as common usage and which refers to any English common names. Chimaera is shark, skate, or ray, but not to chi­ such a name (derived from the Greek maeras. The anglicized word selachian chimair, meaning goat), and it is useful (from the Greek term coined to de sig­ because it covers all one closely re­ nate fishes having cartilaginous skele­ lated group of cartilaginous fishes in­ tons instead of bone) has become even cluding some known as ratfishes, some more restrictive and now refers as elephant fishes, and others. Elasmo­ onl y to s h ark s, not to s kat e s or branch is another word (derived from rays. CLASS CHONDRICHTHYES, THE CARTILAGINOUS FISHES Member s of the c 1 ass Chon­ which are composed of cartilage rather drichthyes, the sharks, skates, rays, than true bone, a feature which sets and chimaeras, possess well-developed them apart from the bony fishes and lower jaws which set them apart from other higher vertebrates. The car­ the lampreys, hagfish, and other lower tilaginous skeletons, however, are often vertebrates; and theypossess skeletons made up of structural components that AMPHIBIA CHONDRICHTIITES (Cartilaginous fishes) OSTEICHTlIYES (Higher bony fishes) PLACODERMI (Archaic: jawed fishes) AGNATHA (Jawless fishes) + NON·VERT£BRAT£ CIIORDAT£S