The Mediterranean Monk seal (Monachus monachus; Figure 1), is currently considered to be facing a ‘very high risk of extinction’. According to the IUCN, it is the most endangered Pinniped species in the world, with less than 600-700 individuals left, of which 300-400 in Greece.
Figure 1 – M. monachus in Mykali Bay.
Mykali Bay is a rocky beach in the south-eastern side of Samos and M. monachus presence is confirmed by several sightings in the last two years. A complete study is necessary in order to identify the ecological and anthropogenic factors influencing the presence of this species. For this reason, our research consists on behavioural land surveys, habitat mapping and marine biodiversity assessment.
LAND SURVEYS
Land surveys are conducted daily at Mykali Bay in order to record the presence of M. monachus individuals in the area. If a Monk seal is spotted, its behaviour such as diving, feeding, etc. is recorded following a specific protocol. In addition to this, the number and type of boats are also noted to assess any anthropogenic disturbances which may influence its presence.
HABITAT MAPPING
An extensive habitat mapping survey is also conducted to identify possible preferences of the Monk seal. Most studies focus on the identification of caves which it inhabits for resting and breeding, but very few on the feeding ecology or more general day-to-day habitat use of this species. The surveys are carried out by snorkeling, recording the type of substrate (sand; cobbles; pebbles; mud; sea grass; Posidonia oceanica; Cymodocea nodosa; Figure 2).
Figure 2 – Habitat Map of Mykali Bay.
FISH IDENTIFICATION
Monk seal primarily feeds on cephalopods but has an opportunistic diet that also includes fish and crustaceans. Fish biodiversity surveys are conducted in order to identify the dietary influence on the pattern of seal presence in the bay. This involves a visual census of randomly selected points to monitor changes in fish abundance and biodiversity over a spatial and temporal scale.
With the current status of the M. monachus population, the collected data will fill the knowledge gap and thus contribute to the conservation of this highly valuable species by allowing decision-making authorities and governmental bodies to identify potentially important areas for the Monk Seal.
Jack Fosberry, Zoology Cardiff University, Wales
