The Mediterranean monk seal has experienced both commercial and illegal hunting since the Middle Ages and has always been threatened with eradication by fishermen.

As of 2022, it is estimated and agreed upon that not more than 600-700 Mediterranean monk seals remain, concentrated primarily along the coasts of Turkey, Cyprus, and Greece.

[1] Some of this successful growth is undoubtedly due to numerous rescue-and-release operations and the relocating of weaned pups to quieter beaches (with lower numbers of predatory sharks and less human interactions), enabling more seals to mature naturally and safely.

[5] The tribe was first conceived by Victor Blanchard Scheffer in his 1958 book Seals, Sea Lions, and Walruses: A Review of the Pinnipedia.

[4] The time of divergence between the Hawaiian and Caribbean species, 3.7 million years ago (Mya), corresponds to the closing of the Central American Seaway by the formation of the Isthmus of Panama.

[9] Fossils of a Pliocene species of monk seal, Eomonachus belegaerensis, have been found in Taranaki region of New Zealand.

Monk seals migrated to Hawaii between 4–11 Mya through an open-water passage between North and South America called the Central American Seaway.

They probably preferred to haul out at sites (low sandy beaches above high tide) on isolated and secluded atolls and islands, but occasionally visited the mainland coasts and deeper waters offshore.

[18] Monk seals as a whole vary minutely in size, with all adults measuring on average 8 feet (2.4 m) and 500 pounds (230 kg).

[16][19][20] The Mediterranean monk seal has a short, broad, and flat snout, with very pronounced, long nostrils that face upwards.

The monk seal's physique is ideally suited for hunting its prey: fish, octopus, lobster, and squid in deep-water coral beds.

Pups are about 3.3 feet (1 m) long and weigh around 33–40 pounds (15–18 kg), their skin being covered by 0.4-to-0.6-inch (1.0 to 1.5 cm) fur, usually dark brown or black.

Caribbean monk seals had a relatively large, long, robust body, and could grow to nearly 8 feet (2.4 m) in length and weighed 375 to 600 pounds (170 to 272 kg).

Hawaiian monk seals have a broad and diverse diet due to foraging plasticity, which allows them to be opportunistic predators that feed on a wide variety of available prey.

[24] Mediterranean monk seals are diurnal and feed on a variety of fish and mollusks, primarily octopus, squid, and eels, up to 6.5 pounds (2.9 kg) per day.

Although no breeding season exists, since births take place year round, a peak occurs in October and November.

However, monk seals of the Cabo Blanco colony may have a gestation period lasting slightly longer than a year.

[28] The Hawaiian monk seal has the lowest level of genetic variability among the 18 pinniped species, allegedly due to a population bottleneck caused by intense hunting in the 19th century.

[29][30] Entanglement can result in mortality, because when the seals get trapped in marine debris such as fishing nets, they cannot maneuver or reach the surface to breathe.

NOAA is funding considerable research on seal population dynamics and health in conjunction with the Marine Mammal Center.

[33] Several causes provoked a dramatic population decrease over 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 them; and on the other hand, coastal urbanization and pollution.

Currently, its entire population is estimated to be less than 600 individuals scattered throughout a wide distribution range, which qualifies this species as endangered.

[35] These two key sites are virtually in the extreme opposites of the species' distribution range, which makes natural population interchange between them impossible.

[36] Cabo Blanco, in the Atlantic Ocean, is the largest surviving single population of the species, and the only remaining site that still seems to preserve a colony structure.

[19] In the Aegean Sea, Greece has allocated a large area for the preservation of the Mediterranean monk seal and its habitat.

[37] 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.

[38] 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 (Akdeniz Foklarını Araştırma Grubu) operating under the Underwater Research Foundation (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.

[41] As early as 1688, sugar plantation owners sent out hunting parties to kill hundreds of seals every night for blubber oil to lubricate machinery.

[42] The Caribbean monk seals' docile nature and lack of an instinctive fear of humans made it an easy target,[43] and hunting only ended (in the 1850s) because the population was too low for commercial use.