The IUCN/SSC Shark Specialist Group
Shark News 7: June 1996
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Status of the kitefin shark Dalatias licha (Bonnaterre, 1788)
Compiled by Leonard J.V. Compagno and Sid F. Cook
Taxonomy
The kitefin shark is a monotypic species in the genus Dalatias, order
Squaliformes. The family Dalatiidae [formerly part of Family Squalidae]
includes the tail-light, pygmy, cigar and cookie-cutter sharks.
Distribution
A relatively common, but unevenly distributed, deeper-water dogfish
found on continental and insular shelves and slopes in warm-temperate
and tropical areas, from 37 m down to 1800 m depth in the north and
central Atlantic, western Indian Ocean, and western and central
Pacific Ocean. It is an epibenthic species, but often ranges well-off the
bottom.
Ecology and reproduction
The kitefin shark is an adept and powerful deep-sea predator feeding
on a broad variety of bony fishes and elasmobranchs. It also consumes
cephalopods, crustaceans, and annelid worms. Harvest records from
Mediterranean fisheries indicate that this is not a schooling species,
but primarily a solitary shark.
An ovoviviparous species, giving birth to 10-16 pups per litter.
Size at birth is about 30 cm. Maximum size of adult males is at least
1.2 m, and adult females at least 1.6 m. Little, if anything, is known
about growth, age at maturity, or life span in the wild.
Threats
This shark has long been exploited commercially. Among products
derived from it were or are: denticle-intact skin for use as "shagreen"
for polishing in cabinet and jewelry making; fishmeal; leather
(considered excellent for the manufacture of "boroso", a durable,
almost armor-like denticle-intact polished leather in Spain); human
consumption (eastern Atlantic and Japan); and squalene oil (Portugal
and Japan).
The Portuguese have developed a limited deep-water fishery that
harvests several hundred tons a year. This fishery appears to be
extremely limited in its potential, with rapid degradation of stocks
noted when more than around 900 mt are taken in a fishing season
(J.G. Casey, personal communication).
Because of the generally great depth at which this species appears
to spend most of its time, historically it was taken primarily in deep-water
directed fisheries efforts. However, with recent trends in
development of deep fishing gear (especially trawl gear) and the
increasing need for commercial fisheries to fish deeper in attempts to
sustain harvest levels, this species and other deep-sea elasmobranchs
will undoubtedly come under increased pressure in the future from
new multi-species fisheries.
IUCN threatened species assessment
Vulnerable (A1d, A2d) throughout its range. This assessment of a 20%
population reduction world-wide within an estimated three generation
period is based on rates of stock and CPUE reduction from present and
former directed fisheries (see Portuguese example above) and the
likely continuation or acceleration of this trend in future as deep water
fisheries effort increases.
Editor's note: The above is a greatly abbreviated version of the
draft account supplied by the compilors for the Shark Action
Plan. The original, including many references, is available
from the Editor.
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