Effects of freshwater availability on the summer distribution of otters Lutra lutra in the southwest coast of Portugal

摘要: The availability of freshwater has been suggested to strongly influence the distribution coastal otters Lutra lutra. test this hypothesis, a study was undertaken on relationships between otter and in coast where is very scarce resource during summer. In area occur mostly few small streams but feed largely sea. Twentynine were surveyed summer 1990, presence/absence signs related nine habitat variables. Freshwater found be most important factor influencing occurrence It that favour large with good vegetation cover, for these are likely maintain frestwater dry periods. also analysed, it tend concentrate particularly near mouth streams. This analysis some conservation implications, indicating decrease or quality can make unsuitable otters, severely decreasing areas suitable species southwest Portugal.