The whiskery shark (''Furgaleus macki'') is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
houndshark
Houndsharks, the Triakidae, are a family of ground sharks, consisting of about 40 species in nine genera. In some classifications, the family is split into two subfamilies, with '' Mustelus'', '' Scylliogaleus'', and ''Triakis'' in the subfamily ...
in the
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Triakidae, and the only member of its
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
. This common shark inhabits the
Australian
continental shelf from
Western Australia
Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...
to the
Bass Strait, to a depth of . It is
demersal in habits and prefers rocky and vegetated
habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...
s. Stout-bodied and almost "humpbacked" in form, the whiskery shark can be distinguished from all other members of its family by the presence of long nasal
barbels
In fish anatomy and turtle anatomy, a barbel is a slender, whiskerlike sensory organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the zebrafish, the black dragonfish and some s ...
. Its two moderately large
dorsal fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...
s are roughly equal in size. It is brownish gray above and lighter below, with a pattern of darker saddles and blotches in younger sharks. This species reaches in length.
The diet of the whiskery shark consists almost entirely of
octopuses. It is
viviparous
Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the ...
; females bear litters of four to 28 pups every other year from August to October, after a
gestation period of 7–9 months. This harmless shark is used for its meat, being one of the species marketed as "
flake
Flake or Flakes may refer to:
People
* Floyd H. Flake (born 1945), A.M.E. minister, university administrator, former U.S. representative
* Jeff Flake (born 1962), American politician
* Christian "Flake" Lorenz, German musician and member of ...
" in Australia. It is mainly caught by a Western Australian
commercial
Commercial may refer to:
* a dose of advertising conveyed through media (such as - for example - radio or television)
** Radio advertisement
** Television advertisement
* (adjective for:) commerce, a system of voluntary exchange of products and s ...
gillnet fishery. Its numbers declined significantly from
overfishing in the 1970s and early 1980s, leading to the introduction of new management measures in the mid-1980s. Since then, strict fishery management has kept the whiskery shark population stable or increasing, resulting in its listing as of
least concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
by the
International Union for Conservation of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of nat ...
.
Taxonomy and phylogeny
Australian
ichthyologist Gilbert Percy Whitley
Gilbert Percy Whitley (9 June 1903 – 18 July 1975) was a British-born Australian ichthyologist and malacologist who was Curator of Fishes at the Australian Museum in Sydney for about 40 years. He was born at Swaythling, Southampton, England ...
described the whiskery shark as a new genus and species, ''Fur macki'', in a 1943 issue of the
scientific journal ''Australian Zoologist''.
As the name ''Fur'' was already in use for the genus ''
Fur
Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket t ...
'' of
true flies
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...
, in 1951, Whitley replaced it with ''Furgaleus''.
The
type specimen
In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...
is a long immature male caught off
Mordialloc
Mordialloc is a beachside suburb in Melbourne, Victoria, Australia, 24 km south-east of Melbourne's Central Business District, located within the City of Kingston local government area. Mordialloc recorded a population of 8,886 at the . ...
in
Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
,
Australia.
Other
common names for the whiskery shark include Mack's whiskery shark, reef shark, shakey shark, and sundowner.
Sharks from the western portion of this species' range were once thought to be a separate species, ''F. ventralis'', until comparative studies by
Leonard Compagno Leonard Joseph Victor Compagno is an international authority on shark taxonomy and the author of many scientific papers and books on the subject, best known of which is his 1984 catalogue of shark species produced for the Food and Agriculture Organ ...
found that they were not significantly different from ''F. macki''.
Based on
morphology
Morphology, from the Greek and meaning "study of shape", may refer to:
Disciplines
* Morphology (archaeology), study of the shapes or forms of artifacts
* Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...
,
Leonard Compagno Leonard Joseph Victor Compagno is an international authority on shark taxonomy and the author of many scientific papers and books on the subject, best known of which is his 1984 catalogue of shark species produced for the Food and Agriculture Organ ...
grouped ''Furgaleus'' with ''
Hemitriakis'', ''
Iago
Iago () is a fictional character in Shakespeare's ''Othello'' (c. 1601–1604). Iago is the play's main antagonist, and Othello's standard-bearer. He is the husband of Emilia, who is in turn the attendant of Othello's wife Desdemona. Iago ha ...
'', and ''
Gogolia'' as the
tribe
The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English is in the discipline of anthropology. This definition is contested, in part due to confli ...
Iagini within the subfamily Galeorhininae of the family Triakidae.
A 2006
phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
study by J. Andrés López and colleagues, based on four
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...
-coding
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
sequences, affirmed that ''Furgaleus'' and ''Hemitriakis'' are sister
taxa
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...
; the study was equivocal regarding the position of ''Iago'' and did not include ''Gogolia''.
Description
The whiskery shark has a moderately stout build, with an almost "humpbacked" appearance. The short snout is rounded or wedge-shaped when viewed from above. This species is the only houndshark in which the flaps of skin preceding the nostrils are elongated into thin
barbels
In fish anatomy and turtle anatomy, a barbel is a slender, whiskerlike sensory organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the zebrafish, the black dragonfish and some s ...
. The horizontally oval eyes are placed high on the head and are equipped with rudimentary
nictitating membranes (protective third eyelids). Beneath the eye is a prominent ridge, and behind it is a tiny
spiracle. The mouth forms a short, wide arch, and bears somewhat long furrows at the corners.
Tooth row
Sharks continually shed their teeth; some Carcharhiniformes shed approximately 35,000 teeth in a lifetime, replacing those that fall out. There are four basic types of shark teeth: dense flattened, needle-like, pointed lower with triangular up ...
s number 24–32 in the upper and 36–42 in the lower jaw. Each upper tooth has an angled, knife-like main cusp with smaller cusplets on the trailing side, while each lower tooth has a single upright cusp. Five pairs of
gill slit
Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks and rays, as well as deep-branching vertebrates such as lampreys. In con ...
s are seen.
The first
dorsal fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...
is rather large and positioned closer to the
pectoral
Pectoral may refer to:
* The chest region and anything relating to it.
* Pectoral cross, a cross worn on the chest
* a decorative, usually jeweled version of a gorget
* Pectoral (Ancient Egypt), a type of jewelry worn in ancient Egypt
* Pectorali ...
than the
pelvic fins, though its origin lies posterior to the pectoral fin rear tips. The second dorsal fin roughly equals the first in size and is positioned slightly ahead of the
anal fin, which is much smaller than either dorsal fin. The
caudal fin
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...
has a short lower lobe and a deep ventral notch near the tip of the upper lobe. Adults are brownish gray above and lighter below; young sharks are lighter in color and have darker saddles and blotches over the body and fins, which fade and may disappear with age.
This species grows up to long and in weight.
Distribution and habitat
Endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...
to Australia, the whiskery shark inhabits
temperate
In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout ...
continental shelf waters from the
North West Cape
North West Cape is a peninsula in the north-west of Western Australia. Cape Range runs down the spine of the peninsula and Ningaloo Reef runs along the western edge. It is in the Gascoyne region and includes the town of Exmouth.
History
In 16 ...
in
Western Australia
Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...
to
Wynyard in
Tasmania
)
, nickname =
, image_map = Tasmania in Australia.svg
, map_caption = Location of Tasmania in AustraliaCoordinates:
, subdivision_type = Country
, subdi ...
. It is most common in the southwestern portion of its range between
Kalbarri and
Albany, and is rare off
Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
and Tasmania. Its range seems to encompass a single population. This species is found
close to the bottom at depths to .
It favors rocky areas and
kelp
Kelps are large brown algae seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance, kelp is not a plant - it is a heterokont, a completely unrelated group of organisms.
Kelp grows in "underwa ...
beds.
Biology and ecology
![Octopus new south wales](https://upload.wikimedia.org/wikipedia/commons/0/03/Octopus_new_south_wales.jpg)
The whiskery shark is an active and highly specialized
predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
, feeding almost exclusively on
octopuses.
Other
cephalopods,
bony fishes, small
rock lobster
"Rock Lobster" is a song written by Fred Schneider and Ricky Wilson, two members of the B-52's. It was twice recorded and released as a single, first by DB Records as their debut release in April 1978, and again the following year for the b ...
s,
spoon worms, and
seagrass
Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the or ...
have also been found amongst its
stomach
The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach i ...
contents.
A known
parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
of this species is the
tapeworm
Eucestoda, commonly referred to as tapeworms, is the larger of the two subclasses of flatworms in the class Cestoda (the other subclass is Cestodaria). Larvae have six posterior hooks on the scolex (head), in contrast to the ten-hooked Cesto ...
''
Calliobothrium pritchardae''.
Like other houndsharks, the whiskery shark is
viviparous
Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the ...
; the developing
embryos are sustained by
yolk
Among animals which produce eggs, the yolk (; also known as the vitellus) is the nutrient-bearing portion of the egg whose primary function is to supply food for the development of the embryo. Some types of egg contain no yolk, for example ...
and probably also maternally produced
histotroph
Uterine glands or endometrial glands are tubular glands, lined by ciliated columnar epithelium, found in the functional layer of the endometrium that lines the uterus. Their appearance varies during the menstrual cycle. During the proliferative ph ...
.
Males can mate every year, while females have a biennial reproductive cycle.
Mating
In biology, mating is the pairing of either opposite- sex or hermaphroditic organisms for the purposes of sexual reproduction. ''Fertilization'' is the fusion of two gametes. ''Copulation'' is the union of the sex organs of two sexually reprod ...
takes place in August and September; females store
sperm until late January to early April of the following year, when the
ova
, abbreviated as OVA and sometimes as OAV (original animation video), are Japanese animated films and series made specially for release in home video formats without prior showings on television or in theaters, though the first part of an OVA s ...
are ready to be
ovulated into the
uterus
The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The ...
. After a 7– to 9-month-long
gestation period, litters of four to 28 (average 19) pups are born between August and October. The litter size increases with the size of the female. The newborns measure long.
Juvenile whiskery sharks are rarely caught by commercial fishers, suggesting that nursery areas may be found in deeper water or other unfished habitats. Pups double to triple in size in the first 15–17 months of life, and continue to grow rapidly until they are 3–4 years old.
Sexual maturity
Sexual maturity is the capability of an organism to reproduce. In humans it might be considered synonymous with adulthood, but here puberty is the name for the process of biological sexual maturation, while adulthood is based on cultural definit ...
is attained at a length of for both sexes, corresponding to around five years of age for males and seven years of age for females. Mature sharks exhibit negligible growth rates, perhaps due to resources being diverted towards reproduction.
The
maximum lifespan is estimated to be 15 years.
Human interactions
Harmless to humans, the whiskery shark is
fished commercially for its meat, which is sold fresh.
It is one of the shark species marketed as "
flake
Flake or Flakes may refer to:
People
* Floyd H. Flake (born 1945), A.M.E. minister, university administrator, former U.S. representative
* Jeff Flake (born 1962), American politician
* Christian "Flake" Lorenz, German musician and member of ...
".
Along with the
dusky shark (''Carcharhinus obscurus'') and the
gummy shark
The gummy shark (''Mustelus antarcticus''), also known as the Australian smooth hound, flake, sweet william or smooth dog-shark, is a shark in the family Triakidae. These small to medium-sized bottom-dwelling sharks are found mostly in, but are ...
(''Mustelus antarcticus''), it is targeted by a shark fishery operating off Western Australia, currently managed as the Western Australian Joint Authority Southern Demersal Gillnet and Demersal Longline Fishery. The fishery began in the 1940s with a small number of
demersal longline vessels, though the whiskery shark was not caught in substantial numbers until the 1970s, with the introduction of
monofilament gillnets,
hydraulic
Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counte ...
net haulers, and additional vessels. Catches peaked in the early 1980s, when 400–600 tons were taken annually.
Overfishing reduced the population to <30% of pre-exploitation levels by the mid-1980s, prompting the Western Australian government to enact a management plan that stabilized the population at 25–30% of pre-exploitation levels.
In 1995, the management advisory committee for the Western Australian shark fishery recommended that the whiskery shark
stock be rebuilt to 40% of pre-exploitation levels by the 2010/11 season, through a series of fishing effort reductions. Although this target was not met because the effort reductions were not completed until 2000/01, preliminary
catch per unit effort data indicate that the population is increasing.
In 2004/05, this species made up 12% (153 tons) of the fishery by weight.
The whiskery shark is also a minor catch of the southern shark fishery, which does not threaten the species overall. Since its population is stable and regularly monitored, and the fisheries that affect it are well-managed, the International Union for Conservation of Nature has assessed this species as least concern.
References
External links
Fishes of Australia : ''Furgaleus macki''
{{Taxonbar, from=Q2607925
whiskery shark
Marine fish of Southern Australia
whiskery shark