The leopard seal (''Hydrurga leptonyx''), also referred to as the sea leopard, is the second largest species of
seal
Seal may refer to any of the following:
Common uses
* Pinniped, a diverse group of semi-aquatic marine mammals, many of which are commonly called seals, particularly:
** Earless seal, also called "true seal"
** Fur seal
** Eared seal
* Seal ( ...
in the
Antarctic
The Antarctic (, ; commonly ) is the polar regions of Earth, polar region of Earth that surrounds the South Pole, lying within the Antarctic Circle. It is antipodes, diametrically opposite of the Arctic region around the North Pole.
The Antar ...
(after the
southern elephant seal
The southern elephant seal (''Mirounga leonina'') is one of two species of elephant seals. It is the largest member of the clade Pinnipedia and the order Carnivora, as well as the largest extant marine mammal that is not a cetacean. It gets its ...
). It is a top order predator, feeding on a wide range of prey including
cephalopods
A cephalopod is any member of the molluscan Taxonomic rank, class Cephalopoda (Greek language, Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral symm ...
, other
pinnipeds
Pinnipeds (pronounced ), commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant families Odobenidae (whose only living member is the walr ...
,
krill
Krill ''(Euphausiids)'' (: krill) are small and exclusively marine crustaceans of the order (biology), order Euphausiacea, found in all of the world's oceans. The name "krill" comes from the Norwegian language, Norwegian word ', meaning "small ...
,
fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
, and
birds
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...
, particularly
penguins
Penguins are a group of aquatic flightless birds from the family Spheniscidae () of the order Sphenisciformes (). They live almost exclusively in the Southern Hemisphere. Only one species, the Galápagos penguin, is equatorial, with a sm ...
, and its only natural
predator
Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...
being the
orca
The orca (''Orcinus orca''), or killer whale, is a toothed whale and the largest member of the oceanic dolphin family. The only extant species in the genus '' Orcinus'', it is recognizable by its black-and-white-patterned body. A cosmopol ...
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
''Hydrurga''. Its closest relatives are the
Ross seal
The Ross seal (''Ommatophoca rossii'') is a true seal (family Phocidae) with a range confined entirely to the pack ice of Antarctica. It is the only species of the genus ''Ommatophoca''. First described during the Ross expedition in 1841, it is ...
, the
crabeater seal
The crabeater seal (''Lobodon carcinophaga''), also known as the krill-eater seal, is a true seal with a circumpolar distribution around the coast of Antarctica. They are the only member of the genus ''Lobodon''. They are medium- to large-sized ( ...
and the
Weddell seal
The Weddell seal (''Leptonychotes weddellii'') is a relatively large and abundant Earless seal, true seal with a Subantarctic, circumpolar distribution surrounding Antarctica. The Weddell seal was discovered and named in the 1820s during expediti ...
, which are all Antarctic seals of the
tribe
The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...
Lobodontini
The true seal tribe Lobodontini, collectively known as the Antarctic seals or lobodontin seals, consist of four species of seals in four genera: the crabeater seal (''Lobodon carcinophaga''), the leopard seal (''Hydrurga leptonyx''), the Weddell ...
.
Research history and taxonomy
Henri Marie Ducrotay de Blainville
Henri Marie Ducrotay de Blainville (; 12 September 1777 – 1 May 1850) was a French zoologist and anatomist.
Life
Blainville was born at Arques-la-Bataille, Arques, near Dieppe, Seine-Maritime, Dieppe. As a young man, he went to Paris to study a ...
, a French zoologist, described the leopard seal in 1820 from a
stuffed specimen
Taxidermy is the Art (skill), art of preserving an animal's body by mounting (over an armature (sculpture), armature) or stuffing, for the purpose of display or study. Animals are often, but not always, portrayed in a lifelike state. The word ' ...
from the collection of one M. Hauville, in
Le Havre
Le Havre is a major port city in the Seine-Maritime department in the Normandy (administrative region), Normandy region of northern France. It is situated on the right bank of the estuary of the Seine, river Seine on the English Channel, Channe ...
. The skin that produced this work of taxidermy was sourced from "the southern seas", that he ascertained to be from around the
Falkland Islands
The Falkland Islands (; ), commonly referred to as The Falklands, is an archipelago in the South Atlantic Ocean on the Patagonian Shelf. The principal islands are about east of South America's southern Patagonian coast and from Cape Dub ...
. Blainville describes the specimen as "beautiful", 7-8 "pieds" long ( long) and elongated, the form and features of the head resembling the "phoque moine" or
monk seal
Monk seals are earless seals of the tribe Monachini. They are the only earless seals found in tropical climates. The two genera of monk seals, ''Monachus'' and ''Neomonachus'', comprise three species: the Mediterranean monk seal, ''Monachus monac ...
, with a small number of
whiskers
Whiskers, also known as vibrissae (; vibrissa; ) are a type of stiff, functional hair used by most therian mammals to sense their environment. These hairs are finely specialised for this purpose, whereas other types of hair are coarser as ta ...
short and simple in shape. Blainville was not able to find the ear opening. The "
anterior
Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...
British Antarctic Survey
The British Antarctic Survey (BAS) is the United Kingdom's national polar research institute. It has a dual purpose, to conduct polar science, enabling better understanding of list of global issues, global issues, and to provide an active prese ...
was killed by a leopard seal while conducting research
snorkeling
Snorkeling (American and British English spelling differences#Doubled in British English, British and Commonwealth English spelling: snorkelling) is the practice of human swimming, swimming face down on or through a body of water while breathing ...
in
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...
. This was the first recorded human fatality attributed to a leopard seal. Brown was part of a team of four researchers taking part in an underwater survey at South Cove, near the U.K.'s
Rothera Research Station
The Rothera Research Station is a British Antarctic Survey (BAS) base on the Antarctic Peninsula, located at Rothera Point, Adelaide Island. Rothera also serves as the capital of the British Antarctic Territory, a British Overseas Territor ...
. Brown and another researcher, Richard Burt, were snorkeling in the water. Burt was snorkeling at a distance of 15 metres (nearly 50 feet) from Brown when the team heard a scream and saw Brown disappear deeper into the water. She was rescued by her team, but they were unable to
resuscitate
Resuscitation is the process of correcting physiological disorders (such as lack of breathing or heartbeat) in an acutely ill patient. It is an important part of intensive care medicine, anesthesiology, trauma surgery and emergency medicine. ...
her. It was later revealed that the seal had held Brown underwater for around six minutes at a depth of up to , drowning her. Furthermore, she suffered a total of 45 separate injuries (bites and scratches), most of which were concentrated around her head and neck.
In a report read at the inquiry into Brown's death, Professor Ian Boyd from the
University of St Andrews
The University of St Andrews (, ; abbreviated as St And in post-nominals) is a public university in St Andrews, Scotland. It is the List of oldest universities in continuous operation, oldest of the four ancient universities of Scotland and, f ...
stated that the seal may have mistaken her for a fur seal, or been frightened by her presence and attacked in defence; Professor Boyd said that leopard seal attacks on humans were extremely rare, but warned that they may potentially become more common due to increased human presence in Antarctica. The coroner recorded the cause of death as “accidental” and “caused by drowning due to a leopard seal attack”.Gyford, Sue (2003-11-14) . ecophotoexplorers.com. Retrieved on 2019-08-20
Conservation
The only known predators of the leopard seals are orcas and sharks. Because they are limited to a subpolar distribution in the Antarctic, they may be at risk as
polar ice cap
A polar ice cap or polar cap is a high-latitude region of a planet, dwarf planet, or natural satellite that is covered in ice.
There are no requirements with respect to size or composition for a body of ice to be termed a polar ice cap, nor a ...
s diminish with global warming. In the wild, leopard seals can live up to 26 years old. Leopard seal hunting is regulated by the
Antarctic Treaty
The Antarctic (, ; commonly ) is the polar region of Earth that surrounds the South Pole, lying within the Antarctic Circle. It is diametrically opposite of the Arctic region around the North Pole.
The Antarctic comprises the continent of A ...
and the Convention for the Conservation of Antarctic Seals (CCAS).
Notes
References
General references
*
* Heacox, Kim. (2006) Deadly Beauty. ''National Geographic'', November 2006
* Saundry, Peter. (2010 Leopard Seal. ''Encyclopedia of Earth''. Topic ed. C. Michael Hogan, editor-in-chief Cutler Cleveland, NCSE, Washington DC