Observations on the use of grottos by Mediterranean Monk seals (Monachus monachus)

Abstract

A group of six Monk seals (Monachus monachus) was discovered to lie up inside a grotto on the shores of a lake reached via an underwater passage. Nearly 1200 hours of observation on the movement of the seals showed that the greatest use of the grotto was made during the winter months and when the wind was towards the grotto entrance. Entry and exit times were not significantly affected by sea state, dark or light, nor were they significantly correlated with sunrise and sunset times or sea and air temperature. These variables did not significantly affect the length of stay in the grotto. Entry occurred most frequently in the early morning and exist at night. Discussion is given of the possible reasons why grottos are used by Monk seals. This appears to be a recent adaptation which may be related to the effects of human disturbance.

Insights from 180 years of mitochondrial variability in the endangered Mediterranean monk seal (Monachus monachus)

“…). Although the ability of MMS to use marine caves for pupping and shelter may have temporarily saved the species from extinction (Bareham and Furreddu ), it will be crucial for its long‐term survival to know whether the low genetic diversity observed in the species is associated with inbreeding depression, lower fitness and lower adaptability as predicted in population genetics theory (Lande , Spielman et al . , Frankham ).…”

Le phoque moine, Monachus monachus (Hermann, 1779), en Grèce

“…La structure de cet habitat a e*te decrite par Postel (1950), , Ronald et Healey (1974), Bareham et Furreddu (1975), Maigret, Trotignon et Duguy (1976).…”

“…Bareham et Furreddu (1975) signalent qu'elle est plus active la nuit que le jour. Quelques observations sur Factivite et le comportement en mer des phoques moines ont ate faites par Tun de nous (Duguy, 1976 ;Maigret, Trotignon et Duguy, 1976) en Mauritanie.…”

“…Ce comportement, qui est tres developpe chez Monachus schauislandi (Butler et Uduardy, 1966 ;Ohata et /., 1972 ;Kenyon et Rice, 1959), n'est pas tres apparent chez 1'espece mediterraneenne oil il semble meme avoir regresse (Bareham et Furreddu, 1975) en raison de la persecution dont il est 1'objet.…”

PUP SURVIVAL IN THE MEDITERRANEAN MONK SEAL (MONACHUS MONACHUS) COLONY AT CABO BLANCO PENINSULA (WESTERN SAHARA‐MAURITANIA)

“…There is little information on pup survival rates and causes of mortality for the Mediterranean monk seal, one of the most endangered mammals worldwide (Reijnders et al 1993). The data on pup mortality comes from seals killed by fishermen or accidentally entangled in fishing gear reported in Greece (Cebrian andVlachoutsikou 1991, Panou et al 1993) and dead pups found stranded on the beaches or found inside caves in the colony of Cab0 Blanco, Western Sahara-Mauritania (Maigret et al 1976, Trotignon 1979, Marchessaux and Muller 1987 and Sardinia (Bareham and Furredu 1975).…”