Ecology and behaviour

Abstract

Characteristically, hagfishes are adapted for life at considerable depths at high salinities and low light intensities, but within the group there are distinct species differences, particularly in the depths to which they penetrate. Myxine glutinosa normally occurs between 50–100 m, but has been recorded down to 1100 m off the Norwegian coast and in Japanese waters M. garmani is found between 400–800 m. In some inner fiords, M. glutinosa may occur in much shallower water at about 30 m, but in these areas there may be marked stratification with the freshwater overlying water of high salinity (Tambs-Lyche, 1969). Myxine is apparently less tolerant of reduced salinity than some species and this may explain its absence from the Baltic. From its distribution, it has been inferred that the upper temperature limit for this species is between 10–13°C. When hauled to the surface in a trap from deep water, the animals are stressed by the rapid change in salinity and exude large quantities of mucus.