Last updated on April 18, 2014 at 12:48 EDT

Mediterranean Monk Seal, Monachus monachus

The Mediterranean monk seal (Monachus monachus) is a rare pinniped, or “fin-footed mammal” that can be found in areas of the Mediterranean Sea, as well as in the Atlantic waters of the Tropic of Cancer. Not much is known about the chosen land habitats of this seal, but until the 20th century, it could be seen relaxing or pup rearing on open beaches. It now dwells in underwater caves and caverns in order to escape human actions including tourism and expansion.

The Mediterranean monk seal can reach an average body length of up to 7.95 feet, and weigh an average of 530 to 880 pounds depending on the sex. The coloring of this seal also depends on the sex, with males appearing to be darker gray in color with white underbellies, and females appearing to be browner in color with pale underbellies. The short flippers bear thin claws, and unlike most species of pinnipeds, the Mediterranean monk seal has two pairs of retractable abdominal teats. Its nostrils are long and drawn upwards, a trait that is characteristic to its species.

There is no defined breeding season for the Mediterranean monk seal, although many births occur between the months of October and November.  It is thought that males are territorial of the females that they mate with, and that mating is polygynous. Each pup is born weighing approximately 39 pounds, with an average body length of 3.2 feet. They are covered in long, dark hair and a white or cream stripe on their underbelly. The long hair will molt and turn into the short hair of an adult at six to eight weeks of age.

Mediterranean monk seal pups will enter the water at two weeks of age, but are not weaned until 18 weeks of age. Mothers have been known to leave their young for as long as nine hours a day to eat. Typically, full maturation occurs at four years of age.

Although little is known about the mating and reproductive habits of the Mediterranean seal, it is estimated that less than half of pups born will live to molt their fur. In Cabo Blanco, studies were conducted that suggested that only 29 percent of pups born from September to January would survive. In this area, it is common for water surges to flush out the caves where mother seals give birth, and so survival rates are very low. It is thought that a lack of genetic diversity may also cause increased mortality.

The Mediterranean monk seal is diurnal, and will swim as deep as 1640 feet to search for food, although the average depth is between 150 to 230 feet. They prefer open areas to forage, and are skilled at scouring the ocean floor. They most commonly consume octopi, eels, and squid and can eat up to 6.6 pounds a day.

The habitat of the Mediterranean monk seal has changed drastically, and therefore, sightings of them have become rare. One report in 2008 stated that a mother was seen feeding her young on the beach of Cabo Blanca, suggesting that the species could make a comeback onto open beaches for breeding purposes. Another recent incident occurred in 2010, on a remote island in the Aegean Sea, where the Mom Hellenic Society spotted a colony on the beach. The location was not released, in order to keep the colony safe, and the organization proposed a plan to the Greek Government to integrate the island into an area where marine life is protected. Other sightings occurred in 2009 and 2011.

In 1997, the colonies of the Mediterranean monk seal located on Cabo Blanco suffered a massive die off, decreasing the species’ already low numbers by two thirds. It was thought that the devastation was caused by a toxic algae bloom, or by a morbilivirus. The current population in this area is thought to be only 150 individuals, and that if another deadly incident occurred, it could wipe out vital population.

The previous range of the Mediterranean monk seal was much larger than today, encompassing an area extending from Northwest Atlantic Africa through the Mediterranean and Black Sea, reaching as far north as Atlantic France and continental Portugal. This range including all of the coasts of islands within the Mediterranean Sea, as well as the Atlantic Islands of Canary, Porto Santo, and others.

This large range has decreased mainly due to human activities such as commercial hunting throughout the years, habitat destruction, and pollution. In the Black Sea, the last known seal was recorded in the 1990’s, and the populations in the Sea of Marmara have gone extinct. The populations still in existence occur at opposite ends of its range, making it nearly impossible to bring them together.

Currently, the estimated population of all Mediterranean monk seals number only 600 individuals, and because of this and its fragmented habitats, it is listed on the IUCN Red List as “Critically Endangered”. In the Aegean Sea, one of two locations with a viable population, there are an estimated 250-300 seals in Greece, and only 100 seals in Turkey. The Western Saharan portion of Cabo Blanco supports a smaller population of 130 seals. Other areas hold populations of less than 50 seals, including Madeira, Desertas Islands, the Ionian Sea, and southwestern Turkey. Some of these populations hold as little as five individuals.

Overhunting of the Mediterranean monk seal occurred mostly due to uncommon fish farm attacks and fish netting damage in Turkey and Greece. The locals considered the seals a pest, and hunted them more out of revenge than species control. In these areas, efforts have been taken to educate the locals about damage control and conservation, and these efforts have proved successful in the past ten years.

The only area in the Aegean Sea to create protected land for these seals, Greece, underwent difficulties in the process due to extreme secrecy. Despite this, the Alonissos Marine Park was created to preserve the populations and habitats of the seals, and extends around the main area where the Mom Organization is active, the Northern Sporades islands. Because of the efforts of this organization, most people are aware that the seals need protection and there are considerations that perhaps another site could be set aside for the seals, located at a known breeding site. Because of the concealment of the efforts to create protected land in Greece, and the government’s negative outlook on the idea, William Johnson was inspired to write a book covering the 1970’s politics of that time.

One of the largest groups of conservationists working to preserve the Mediterranean monk seal is the Mediterranean Seal Research Group, known in Turkish as Akdeniz Foklarını Araştırma Grubu. Under the management of the Underwater Research Foundation, known as Sualtı Araştırmaları Derneği in Turkish or SAD-AFAG, this group has collaborated with Foca public officials in many conservation efforts, including setting up phone, email, and fax hotlines meant for sightings of these rare seals.

Image Caption: The Natural history museum in Milan, Italy. Diorama with a Monachus monachus (Monk seal). Credit: Giovanni Dall’Orto/Wikipedia(CC BY-SA 2.5)

Mediterranean Monk Seal Monachus monachus