The
Mediterranean Monk Seal (
Monachus
monachus) is a
pinniped belonging to
the
Phocidae family: at some 350-450
remaining individuals it is believed to be the world's second
rarest pinniped (only to the
Saimaa
Ringed Seal) while
IUCN Red List
assumes there are fewer than 600 left, and one of the most
endangered mammals in the world.
It is
present in parts of the Mediterranean Sea
and the Eastern Atlantic Ocean
waters around the Tropic of Cancer
as well.
Description
This species of
monk seal grows from
approximately 80 cm long at birth to an average of 2.40 m in
adults. The latter weigh up to 320 kg, females being slightly
smaller than males.
Pups are born in a black natal fur, often with a white patch
beneath whose shape can be used to identify individuals for the
rest of their lives. The average lifespan of these animals is
unknown, but is thought to be somewhere around 20–25 years;
reproductive maturity is reached at around age four
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.
There are 8 pairs of teeth in both jaws.Believed to have the
shortest hair of any pinniped, the Mediterranean monk seal fur is
black (males) or brown to dark grey (females) with a paler belly
which is close to white in males. The snout is short broad and
flat, with very pronounced, long nostrils that face upward, unlike
their
Hawaiian relative who tend
to have more forward nostrils. The flippers are relatively short,
with small slender claws. Monk Seals have two pairs of retractable
abdominal teats unlike most other pinnipeds.
Reproduction
Very little is known of this seal's reproduction. Scientists have
suggested that these seals are
polygynous,
with males being very territorial where they mate with females.
Although there is no breeding season since births take place year
round, there is a peak in October and November.
This is also the time
when caves are prone to wash out due to high surf or storm surge, which causes high mortality rates
among monk seal pups, especially at the key Cabo
Blanco
colony. According to the IUCN species
factsheet "pup survival is low; just under 50% survive their first
two months to the onset of their moult, and most mortalities
occurred in the first two weeks. Survival of pups born from
September to January is 29%. This very low survival rate is
associated with mortality caused by severe storms, and high swells
and tides, but impoverished genetic variability and inbreeding may
also be involved. Pups born during the rest of the year had a
survival rate of 71%"
In 2008 lactation was reported in an open beach, the first such
record since 1945, which could suggest that the seal could begin
feeling increasingly safe to return to open beaches for breeding
purposes in Cabo Blanco
Pups make first contact with the water two weeks after their birth,
and are weaned at around 18 weeks of age; females caring for pups
will go off to feed for an average of nine hours. Most individuals
are believed to reach maturity at 4 years of age. The gestation
period lasts close to a year. However, it is believed to be common
among monk seals of the Cabo Blanco colony to have a gestation
period lasting slightly longer than a year.
Diet
The Mediterranean Monk Seals are
diurnal and feed on a variety of
fish and
mollusks, primarily
octopus,
squid and
eels, up to 3 kg per day. They are known
to forage, mostly, at depths of 150-230 feet, but (as a species)
have been observed by the
NOAA in a submersible
at a known feeding ground at a depth of 500m. Monk Seals prefer
hunting in wide-open spaces enabling them to utilise their speed
more effectively. They are successful bottom feeding hunters and
have been observed (as a species) lifting slabs of rock in search
of prey.
Habitat
The habitat of this
seal has changed over
the years. In ancient times, and up until the 20th century,
Mediterranean Monk Seals had been known to congregate, give birth,
and seek refuge on open beaches. In more recent times, they have
left their former habitat and, now, only use sea caves for such
things, and more often than not, these caves are rather
inaccessible to humans due to under-water entries, and because the
caves are often positioned along remote or rugged coastlines.
Scientists have confirmed that this is a recent adaptation, most
likely due to the rapid increase in human population, tourism and
industry, which have caused the destruction of animals' habitat.
Because of these seals' shy nature and sensitivity to human
disturbance, they have slowly adapted to try avoid contact with
humans completely within the last century, and, perhaps, even
earlier than that. The coastal caves are however dangerous for
newborns, and are major mortality cause among pups.
Status
This
earless seal's former range extended
throughout the Mediterranean
Sea and Black
Sea
coastlines including all offshore islands of the
Mediterranean, and into the Atlantic
and its
islands as far West as the Azores.
Vagrants could be found as far South as
Gambia
and the Cape Verde
islands and as far North as continental Portugal
and Atlantic France.
Several causes have provoked a dramatic population decrease over
the time, on one hand, commercial hunting (especially during the
Roman Empire and Middle Ages) and, during the 20th century,
eradication by fishermen – who used to consider it a pest due to
the damage the seal causes to fishing nets when it preys on fish
caught in those – and, on the other hand, coastal urbanisation and
pollution.
The
species has gone extinct in the Sea of Marmara
, due to pollution and heavy ship traffic from the
Dardanelles
and the Bosphorus
. In addition, the last report of a seal in
Black
Sea dates to the late 1990s.
Nowadays its entire population is estimated to be less than 500
individuals scattered throughout 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.
One is the Aegean Sea
(150-200 in Greece and some 100 in Turkey) and the
other is the Western
Saharan
portion of Cabo Blanco (some 130 individuals which may support the small
but growing nucleus in the Desertas Islands
–approximately 20 individuals).
These two key sites for the species are virtually in the extreme
opposites of its distribution range, which makes natural population
interchange between these two key sites impossible. All the other
remaining subpopulations are composed by less than 50 mature
individuals, many of them being only loose groups of extremely
reduced size –often less than 5 individuals.
These
other remaining populations are in Madeira
and the
Desertas
Islands (both in the Atlantic Ocean) South-Eastern
Turkey
and the Ionian Sea
(both in the Eastern Mediterranean).
The
species status is virtually moribund in the Western Mediterranean,
which still holds tiny Moroccan
and Algerian
populations, associated to rare sightings of
vagrants in the Balearic
Islands
, Sardinia and other Western
Mediterranean locations.
Cabo Blanco 1997 die off
Cabo Blanco, in the Atlantic Ocean, is the largest surviving single
population of the species and the only remaining site which still
seems to preserve a colony structure. In the summer of 1997, two
thirds of its seal population were wiped out within the space of
two months, extremely compromising the species'
viable population. While opinions on the
precise causes of this epidemic remain divided (the most likely
cause being a
morbilivirus
or, more likely, 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 early 1997 count, 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 some 300 in 1997 but still the largest
single colony by far. The threat of a similar incident that could
wipe out this entire population remains.
Preservation
Damage
inflicted upon afschermen nets and rare attacks on off-shore fish
farms in Turkey
and Greece
are known to
have pushed local people towards hunting the Mediterranean monk
seal, but mostly out of revenge rather than population
control. Preservation efforts have been put forth by civic
organizations, foundations and universities in both countries since
as early as the 1970s. For the past 10 years, many groups have
carried out missions to educate locals on damage control and
species preservation. Reports of positive results of such efforts
exist throughout the area.
In the Aegean Sea, only Greece has allocated a vast area for the
preservation of the Mediterranean monk seal and its habitat.
The Greek
Alonissos
Marine Park
, that extents around the Northern Sporades
islands, is the main action ground of the Greek MOm
organisation. MOm is greatly involved in raising awareness
in the general public, fundraising for the helping of the monk seal
preservation cause, in Greece and wherever needed. Greece, is
currently looking into the possibility of declaring another monk
seal breeding site as a National park, and also has integrated some
sites in the NATURA 2000 protection scheme. It should be stated
that the legislation in Greece is very strict towards the hunting
of the seal and in general the public is very much aware and
supportive of the effort for the preservation of the Mediterranean
monk seal.
The complex politics concerning the covert opposition of the Greek
government towards the protection to the Monk Seals in the Eastern
Aegean in the late 1970s is described in a book by
William Johnson . It appears that oil
companies may have been using the Monk Seal Sanctuary project as a
stalking horse to encourage greater cooperation between the Greek
and Turkish governments as a preliminary to pushing for oil
extraction rights in a geopolitically unstable area. According to
William Johnson The Greek secret service, the YPEA, were against
such moves and sabotaged the project to the detriment both of the
seals and conservationsists, who unaware of such covert
motivations, sought only to protect the species and its
habitat.
One of
the largest groups among the foundations concentrating their
efforts towards the preservation of the Mediterranean monk seal is
the Mediterranean Seal Research Group (Turkish:
Akdeniz Foklarını Araştırma Grubu) operating under the
Underwater Research Foundation (Turkish: Sualtı
Araştırmaları Derneği) in Turkey (also known
as SAD-AFAG). The group has taken
initiative in joint preservation efforts together with the Foça
municipal officials, as well as phone, fax and
email hotlines for sightings.
Preservation of the species requires both the preservation of land
and sea, due to the need for terrestrial
haul-out sites and caves or caverns for the
animal to rest and reproduce. Even though responsible
SCUBA instructors hesitate to make trips to
known seal caves, just the rumor of a seal sighting quickly becomes
a tourist attraction for many. Irresponsible SCUBA trips shy the
Mediterranean monk seal away from caves of potential habitation
spots for the species.
See also
Notes
- [1]
- http://www.monachus-guardian.org/news/news080620.htm
- The Monachus Guardian Mediterranean Monk Seal Fact
Sheet
- WWF news report on fishermen becoming guardians of
the Mediterranean monk seal in Turkey
- http://www.mom.gr
- "The Monk Seal Conspiracy"
- SAD-AFAG Contact Details
References
William Johnson, (1988),
The Monk Seal Conspiracy, Heretic
Books ISBN 0-946097-23-2
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