The Mediterranean monk seal is the only seal found
in the Mediterranean Sea and is the most endangered pinniped in the world.
Odyssey Chief Scientist Simone Panigada caught a rare glimpse of the animal in the Aegean Sea, Greece.
Photo : Courtesy of Stefano Agazzi - Tethys Institute
July 7, 2004
The Mediterranean Monk Seal
Real Audio Report
This is Genevieve Johnson speaking to you from the Odyssey in the Mediterranean Sea.
Cetaceans (whales, dolphins and porpoises) and pinnipeds (seals and sea lions) have been hunted for millennia. In most cases, large-scale commercial hunts occurred in the last two or three hundred years. Unregulated exploitation reduced many populations to small fractions of their original sizes, while other species disappeared altogether.
Today through the proliferation of synthetic nets, various fisheries practices have replaced hunting as the single greatest human threat to marine mammals - deaths of cetaceans and pinnipeds may run into the millions annually due to entanglements and directed hunts. In many areas some fishermen compound the problem by intentionally killing marine mammals in order to eliminate what they perceive as competition for dwindling fish stocks.
The Mediterranean Sea is home to the most endangered pinniped on the planet - the Mediterranean monk seal (Monachus monachus). The Mediterranean monk seal is the only pinniped found in the Mediterranean Sea. In ancient Greece around 400 BC, monk seals were placed under the protection of the Greek Gods Poseidon and Apollo because they showed such a great love of sea and sun. They were immortalized in the writings of Homer and Aristotle, while one of the first Greek coins minted depicted the head of a monk seal.
The Mediterranean monk seal is a long slender animal with a comparatively small, flat, broad head and upward facing nostrils. They are uniformly black at birth with a distinct white ventral patch unique to each individual. These seals have the shortest hair of any pinniped, changing color from shades of grey to brown to black as they molt and mature, while the ventral patch persists through a life that may span forty years.
Monk seals rest and give birth in secluded coastal caves and inaccessible rocky shorelines. As a result, they are almost impossible to observe in the wild, while attempts to keep them in captivity have failed. Monk seals reach sexual maturity at around four years of age. Their period of gestation seems to last just over a year, with most pups born in late summer to early winter. However, the mortality of young is high in stormy weather due to pups washing out of caves and drowning.
At one stage, three species of monk seal inhabited a large area in the tropical and sub-tropical seas of the northern hemisphere. The Mediterranean monk seal, the Hawaiian monk seal (Monachus schauinsland) and the Caribbean monk seal (Monachus tropicalis) all evolved from a single species that lived more than 15 million years ago off the east coast of the United States.
All three species of monk seal declined dramatically in the 19th and 20th centuries due to excessive hunting. Sadly, the Caribbean monk seal has not been sighted since 1952 and is declared extinct. The two surviving species are listed as critically endangered by the International Union for the Conservation of Nature and Natural Resources (IUCN) and listed on Appendix 1 of the Convention of International Trade in Endangered Species (CITES).
The Hawaiian monk seal is restricted to the northwestern Hawaiian Islands and is slowing recovering from the brink of extinction with a population consisting of approximately 1500 animals. Fortunately, the protected status and isolation of its major breeding grounds provides a moderate buffer.
In contrast, only 450 - 500 Mediterranean monk seals survive in severely fragmented populations. Once occupying an extensive geographical range in the Mediterranean, Marmara and Black Seas, and along the Atlantic coast of Africa and Atlantic islands from Cape Verde to the Azores, the two largest surviving groups are today found in the Aegean and Ionian seas off the coasts of Greece and Turkey in the eastern Mediterranean, and Mauritania and Morocco on the Atlantic coast of northwest Africa. In some areas they may have already declined below a certain critical density necessary for the population to reproduce itself.
The red area illustrates where the Mediterranean monk seal once occupied an extensive geographical range in the Mediterranean,
Marmara and Black Seas, and along the Atlantic coast of Africa and Atlantic islands from Cape Verde to the Azores.
The undisputed leading factor and primary threat to the survival of the few remaining Mediterranean monk seals is human-induced mortality.
Two broad categories of human impacts are recognized - those that prevent an animal from breeding and those that kill the animal outright.
Over-fishing, coastal development and pollution are leading factors causing a decline in the breeding success of the Mediterranean monk seal. In 1997 a large number of seals died along the coast of northwestern Africa from an infectious viral disease. Although opinions on the precise cause vary, few deny that pollution played a significant role. The largest colony at Cabo Blanco Peninsula was reduced from about 300 to 100 animals. The majority of the animals that perished were sexually mature, placing this already critically endangered species in an even more precarious position.
Entanglement in fishing gear and the shooting of seals result in their direct mortality. Some fishermen deliberately kill monk seals, perceiving them as competition for their fish and squid. In 1999 at the 13th European Cetacean Society Annual Conference, a report was presented whereby 113 fishermen from 34 ports in the Aegean Sea were surveyed about the interaction between fisheries and Mediterranean monk seals. Interestingly, only 11.4% of those interviewed considered seals to be the most important problem facing fisheries today. Of the problems reported, over-fishing and illegal fishing were seen as the most serious, with monk seals low on the list of priorities.
However, damage caused to valuable nets by monk seals or other marine animals such as dolphins or turtles may appear to some fisherman as at least one problem that is easy to solve themselves. Although Mediterranean monk seals are protected in Greece and Turkey, they are still being deliberately killed.
The Caribbean monk seal disappeared off the face of the earth while remaining an almost complete mystery to science. We are close to losing the Mediterranean monk seal and still know very little of its biology, ecology and behavior. The installation of video cameras in caves and an increasing network of sightings reports in recent years are increasing our knowledge. This data is helping to implement management and conservation actions such as the creation of protected areas around breeding sights and fisheries buffer zones.
Today, the Mediterranean monk seal survives in small fragmented populations.
While some protected areas are established in Greece and Turkey in the Mediterranean Sea, and Portugal in the Atlantic Ocean, the fragmented populations range through a number of different political jurisdictions. An Action Plan for the Management of the Mediterranean monk seal is in place and coordinated in Athens, Greece. It requires all countries that still have monk seals to cooperate in an immediate and significant reduction in the combination of human pressures. Only a range-wide coordinated recovery effort representing and including all interest groups, will prevent the extinction of the Mediterranean monk seal in the 21st century.
- Perrin, G Wursig, B & Thewissen, J. - Encyclopedia of Marine mammals. Academic Press (2002).
- Reeves, R Stewart, B Clapham, P & Powell, J - Sea mammals of the world. Chanticleer Press (2002).
- Biological Conservation
Volume 116. Issue 3, April 2004, Pages 417 - 431.
- The Mediterranean Monk Seal
Proceedings of the First International Conference Rhodes, Greece. 2-5 May 1978.
- Seal Workshop -
13th European Cetacean Society Annual Conference - Valencia, Spain. April 5, 1999.
Log written by Genevieve Johnson.