Mediterranean Monk Seal
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| Monachus monachus (Hermann, 1779) |
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 Mediterranean Monk Seal range
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The Mediterranean Monk Seal (Monachus monachus) is believed to be the world's rarest pinniped and one of the most endangered mammals of the world.
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[edit] Description
This species of monk seal grows from the approximate 80 cm of newborns to an average 2.40 m length of adults. The latter weigh up to 320 kg, the females being slightly smaller than the males. Their fur is black (males) or brown to dark grey (females) with a paler belly which is close to white in males. Pups are mostly born in autumn, entering the water two weeks afterwards, and are ablactated at around 18 weeks of age. They are born in a black natal fur, often with a white patch beneath. The shape of these patches can be used to identify individuals. The reproductive maturity is reached at around the age of four, and total age is over twenty years. Pregnant Mediterranean Monk Seals typically use inaccessible undersea caves while giving birth, though historical descriptions show that they used open beaches until the eighteenth century.
The Mediterranean Monk Seals are diurnal and feed on fish and mollusks, primarily octopus, up to 3 kg per day.
[edit] Status
This earless seal's former range extended throughout the Mediterranean Sea and Black Sea coasts line and into the Atlantic, as far South as Cape Verde (where it is now extinct) and as far West as the Azores (where it is also extinct as a breeder but there are occasional sightings of mavericks coming from the Desertas population).
Several causes have provoked a dramatic population decrease over the time, mostly commercial hunting (especially during the Roman Empire and Middle Age) and, during the 20th century, eradication by fishermen – who used to consider it a pest due to the damages the seal causes to fishing nets when it preys on fishes caught in those – and coastal urbanisation.
As a result of this its entire population is estimated to be nowadays less than 600 individuals scattered thoughout a wide distribution range, which qualifies this species as Critically Endangered. Its current very sparse population is one more serious threat to the species, as it only has two key sites which can be deemed viable: the Aegean Sea (Greece-Turkey) and, specially, the one in the Western Sahara portion of Cabo Blanco (which may support the small but growing nucleus in the Desertas Islands). These two key sites for the species are virtually in the extreme opposites of its distribution range, which makes natural population interchange impossible.
In the summer of 1997, two thirds of the largest surviving single population of Mediterranean monk seals (the one in Cabo Blanco) was wiped out within the space of two months, extremely compromising the species' viable population. While opinions on the precise causes of this epidemic remain sharply divided (the most likely cause being either a morbilivirus or a toxic algae bloom) the mass die-off emphasised the precarious status of a species already regarded as critically endangered throughout its range. While still far below the beginning of 1997, numbers in this all important location have started a slow paced recovery ever since. Currently the population in this location is estimated at 150 individuals, down from approximately 300 in 1997 but still the largest colony by far. The threat of a similar incident that could wipe it out this entire population remains.[1]
[edit] See also
[edit] References and notes
- Seal Specialist Group (1996). Monachus monachus. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Listed as Critically Endangered (CR C2a v2.3)
- Randall R. Reeves, Brent S. Stewart, Phillip J. Clapham and James A. Powell (2002). National Audubon Society Guide to Marine Mammals of the World. Alfred A. Knopf, Inc. ISBN 0375411410.
