This page focuses on one species of concern.
Mediterranean Monk Seal (Monachus monachus)
Mediterranean monk seals are one of two extant species of the genus Monachus, the only group of seals endemic to tropical and subtropical waters. The Mediterranean monk seal (Monachus monachus) and the Hawaiian monk seal (Monachus schauinslandi) are both classified as critically endangered by the International Union for the Conservation of Nature, and the Caribbean monk seal (Monachus tropicalis) is considered extinct (1-3). The total population of Mediterranean monk seals numbers 350-450 individuals (1).
Although Mediterranean monk seals were originally distributed throughout the Mediterranean and Black Seas, and the northwestern coast of Africa, 60% of the population now exists in small, fragmented colonies (4). The majority of the existing population (250-350) is found in small groups in the northeastern Mediterranean region, including about one hundred along the Mediterranean and Aegean coasts of Turkey (5). A single large colony at Cap Blanc on the African coast once contained over 300 seals, but a devastating mass mortality event in 1997 reduced the population to about 100 individuals (6,7). Another 20-30 seals are found in the Madeira archipelago off the west coast of Africa (8).
Historically, Mediterranean monk seals were exploited for fur and oil. Today the greatest threats are habitat loss, interactions with fishing gear, deliberate killing by fishermen (1,9); genetic drift, and environmental stochasticity associated with small and fragmented populations (6,7). Entanglement in fishing gear is a significant source of mortality throughout most of the species’ remaining scattered distribution (9). Mediterranean monk seals are known to interact with gill nets, trammel nets, longlines, and lures (10) as well as marine fish farms (11). In addition to “stealing” fish, seals will sometimes damage gear by tearing holes in nets to remove fish or breaking off longline hooks (10).
Traditional methods of actively deterring seals from fishing gear and fish farms include using lights and sounds, and chasing seals with boats (10), but these methods are generally ineffective (11). Acoustic deterrent devices are used in other fisheries to deter marine mammals from fishing gear, although there is concern that they could instead attract seals to fishing gear or displace them from important habitat (10,12). Implementation costs and the vast number of fishermen also are prohibitive (9). Other strategies for reducing the risk of seal interactions with coastal fisheries include restricting the amount or the type of fishing gear that can be used in protected areas. A study comparing seal damage by gear type suggests that substituting longlines for nets and reducing soak time could reduce the incidence of seal damage as well as the risk of entanglement (10).
Marine protected areas are often invoked as the ideal solution for protecting breeding habitat and reducing interactions with fishing gear (ex. 9). Several protected areas have been established specifically for the conservation of Mediterranean monk seals. The Turkish fishing port of Foça was designated the Foça Pilot Monk Seal Conservation Area in 1991. Purse seining and trawling are prohibited, though an artisinal fishery of about 40 boats using trammel and gill nets and longlines is still active (10). The National Park Service of Madeira created a Monk Seal Conservation and Monitoring Programme in 1988, and the uninhabited Desertas Islands have been a Nature Reserve since 1990 (Pires et al 2008). Fishing is not permitted in the southern half of the Reserve, where important pupping sites are located (8,9). The National Marine Park of Alonnisos, Northern Sporades (NMPANS) in the Aegean Sea was established in 1992, and most human activity is prohibited within the core zone (9). Entanglement is no longer considered a threat to monk seals in Madeira or in NMPANS (9). Despite these measures, in addition to protection at federal and international levels, Mediterranean monk seals are still in decline and face a serious risk of extinction.
1. Aguilar, A. & Lowry, L. 2008. Monachus monachus. In: IUCN 2008. 2008 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 14 March 2009.
2. Kovacs, K. 2008. Monachus tropicalis. In: IUCN 2008. 2008 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 14 March 2009.
3. Lowry, L. & Aguilar, A. 2008. Monachus schauinslandi. In: IUCN 2008. 2008 IUCN Red List of Threatened Species. <www.iucnredlist.org>. Downloaded on 14 March 2009.
4. Gucu, A.C., Gucu, G., and H. Orek. 2004. Habitat use and preliminary demographic evaluation of the critically endangered Mediterranean monk seal (Monachus monachus) in the Cicilian Basin (Eastern Mediterranean). Biological Conservation 116: 417-431.
5. Güçlüsoy, H., Kiraç, C.O., Veryeri, N.O., and Y. Savaş. 2004. Status of the Mediterranean monk seal, Monachus monachus (Hermann, 1779) in the coastal waters of Turkey. E.U. Journal of Fisheries and Aquatic Sciences 21(3-4): 201-210
6. Harwood, J. 1998. What killed the monk seals? Nature 393: 17-18
7. Forcada, J., Hammond, P.S., and A. Aguilar. 1999. Status of the Mediterranean monk seal Monachus monachus in the Western Sahara and the implications of a mass mortality event. Marine Ecology Progress Series 188: 249-261
8. Pires, R., Neves, H.C., and A.A. Karamanlidis. 2008. The critically endangered Mediterranean monk seal Monachus monachus in the archipelago of Madeira: priorities for conservation. Oryx 42 (2): 278-285
9. Karamanlidis, A.A., Androukaki, E., Adamantopoulou, S., Chatzispyrou, A., Johnson, W.M., Kotomatas, S., Papadopoulos., A., Paravas, V., Paximadis, G., Pires, R., Tounta, E., and P. Dendrinos. 2008. Assessing accidental entanglement as a threat to the Mediterranean monk seal Monachus monachus. Endangered Species Research 5: 205-213
10. Güçlüsoy, H. 2008. Damage by monk seals to gear of the artisanal fishery in the Foça Monk Seal Pilot Conservation Area, Turkey. Fisheries Research 90: 70-77
11. Güçlüsoy, H. and Y. Savas. 2003. Interaction between monk seals Monachus monachus (Hermann, 1779) and marine fish farms in the Turkish Aegean and management of the problem. Aquaculture Research 34: 777-783
12. Reeves, R.R., Read, A.J., and G. Notarbartolo-di-Sciara. 2001. (Eds.) Report of the Workshop on Interactions between Dolphins and Fisheries in the Mediterranean: Evaluation of Mitigation Alternatives. Instituto Centrale Per la Ricerca Applicata al Mare. Roma, 4-5 May 2001, 1-44.