Habitat characteristics and size structure in a population of an endangered lamprey, Lethenteron sp. N, in an urbanized area of Japan

Abstract

For conservation of a lamprey population in an urbanized area, basic properties including taxonomic attribution, habitat characteristics and spatial distribution were investigated. Sequencing analysis of mitochondrial genes suggested that the population belongs to Lethenteron sp. N. The abundance and size distribution of the population varied temporally and spatially. Spawning activity was observed only in the uppermost reach. Although a drop structure at the downstream may prevent the movement of individuals, the presence of many sources of spring water and sandy substrate in the study stream suggested that the local condition of habitat was suitable for this species.