About the Species
The Mediterranean monk seal is one of the rarest marine mammals in the world and one of only a few pinniped species to reside in tropical and subtropical waters. Currently, only approximately 440 to 540 mature individuals remain. Major threats to the Mediterranean monk seal include displacement and habitat deterioration, pollution, deliberate killing by humans, and fisheries bycatch and entanglement. The Mediterranean monk seal is found in the Mediterranean Sea and the eastern Atlantic Ocean along the coast of Northwest Africa. The Mediterranean monk seal is listed as endangered under the Endangered Species Act and depleted under the Marine Mammal Protection Act.
Population Status
The current population of Mediterranean monk seals is limited to 600 or 700 individuals with 350 to 450 mature individuals. In the Cabo Blanco subpopulation the abundance of Mediterranean monk seals is estimated to represent about 3% of its historic abundance. However, the species is showing signs of localized recovery in each of the three existing subpopulations.
Appearance
Newborn pups have a black or dark brown woolly coat called “lanugo” with a white, sometimes spotted, patch on the belly side of the seal. The shape, size, spot-pattern, and position of the patch varies between seals and can be used to identify individual seals and their gender prior to the first molting. When the pup is approximately four to eight weeks old, the first molt occurs, and short, glossy, grey hair replaces the long, black lanugo. At the adult and juvenile stages, the seal’s coat becomes short and bristly. Adult males have a black fur coat and usually retain the white ventral patch. In contrast, adult females typically exhibit a brown or gray coat with a lighter belly.
Behavior and Diet
Historically, monk seals hauled out on open beaches for resting and pupping, but due to centuries of human persecution and disturbance, they have been extirpated from much of their original habitat. Now in response to anthropogenic pressures, females tend to give birth in remote, marine caves. Pupping females prefer caves where they and their pups cannot be seen. These caves also tend to have some light, multiple entrances/escape routes, a low risk of pup washout, interior beaches with soft substrate, and are not easily accessible to humans. Generally, Mediterranean monk seals are thought to dive and feed in shallow, nearshore waters. Mediterranean monk seals are considered opportunistic predators and feed on a variety of prey including bony fishes, cephalopods (mainly the common octopus Octopus vulgaris), and crustaceans.
Where They Live
The current population of Mediterranean monk seals is approximately individuals with 440 to 540 mature individuals. Although the Cabo Blanco population has a positive intrinsic rate of growth of 5.8% per annum at present, the Madeira population has an intrinsic rate of growth of -0.2%.
World map providing approximate representation of the Mediterranean monk seal's range.
Lifespan & Reproduction
Female Mediterranean monk seals typically reach sexual maturity at 3 years of age in Cabo Blanco, and between 6 and 7 years of age in Madeira, while the earliest age males have been observed mating is 7. r. Mating of Mediterranean monk seals takes place in the water. Gestation lasts 9-11 months and females give birth to one pup. Female monk seals can give birth in consecutive years and often give birth within the same few days each year. Although pups may be born year-round, most pupping takes place in autumn.
Threats
Habitat Destruction, Degradation, Disturbance and Pollution
Although the sea cave breeding habitat of the Mediterranean monk seal is theoretically protected in many range states, this habitat is often subject to disturbance from tourism, development, and other human activities. Moreover, these threats may not be monitored or enforced. Additionally, throughout the Mediterranean pollutants are an issue, including legacy pollutants (such as DDT; and trace elements). More recently recognized pollutants that may be a threat include PAHs (polyromantic hydrocarbons) and microplastics.
Disease
Disease decimated the Cabo Blanco population of monk seals in 1997 and still remains a potential threat with recent reports of toxoplasmosis, morbillivirus, and parasite-related fatalities. The high pollutant burden of monk seals may potentially be increasing monk seals’ susceptibility to disease, in synergy with their lack of genetic diversity.
Harassment and Entanglement
The frequency of fishery-related deaths (i.e., deliberate killings and entanglements) are considered one of the main threats preventing the recovery of the Mediterranean monk seal. Deliberate killings are usually committed by fishermen in response to damage to fishing gear or lost catch. Although the deliberate killing of a monk seal is illegal, fishermen have been observed shooting seals and using explosives in occupied caves. Deliberate killing is primarily a threat to this species in the areas of Greece, Turkey, and Cabo Blanco.
Accidental entanglement in fishing gear and drowning as a result of entanglement (especially in static nets) is also a major source of mortality, particularly for sub-adult monk seals in the eastern Mediterranean. Tempted by an easy meal, younger seals tend to be less cautious and experienced than adults when approaching nets and often are not strong enough to disentangle themselves. Monk seals can become entangled in a wide variety of fishing gear, including set-nets, trawl nets, and long lines.
There appears to be optimism for the species with grants being provided by EU programs for monk seal outreach and research projects, and protected areas are being established. However, although there have been considerable efforts to establish protected areas, develop regulations, and formulate action plans for the conservation of Mediterranean monk seals, in several areas there is a lack of monitoring, implementation and enforcement of laws and conservation measures.
Scientific Classification
| Animalia |
Chordata |
Mammalia |
Carnivora |
Phocidae |
Monachus |
monachus |
Last updated by NOAA Fisheries on 04/14/2025
