Some factors influencing the distribution of otters (Lutra lutra)

Abstract The number of sites at which evidence of otters was found and the total number of signs were recorded on fifty 5‐km stretches of rivers in Wales and the West Midlands of England. Data were collected on fifteen parameters of habitat considered to be of importance to otters and subjected to a multivariate analysis. Evidence of otters was found at thirty‐four stretches. The distribution of sites and signs was correlated with the presence of potential holts (of which 107 were found) and with mature sycamore and ash trees. The measured variables accounted for 52 5% of the overall variation in otter sites and 60 2% of the variation in otter signs. The conservation of otters is discussed in light of the results of the analysis.