Larval abundance of burbot Lota lota in the pelagic zone of Lake Constance, Germany, peaked during April and remained at a constant but lower level until mid-June. From the end of May onwards a significant diel vertical migration pattern was observed: while burbot larvae were distributed above as well as below the thermocline in the daytime with the highest percentages of abundance at water depths of 30 and 50 m (below the thermocline) on 5 and 25 June, they were concentrated from 2 to 15 m (above the thermocline) during the night. This migration pattern coincided with a significant decline in the food items preferred by burbot at this life stage, cyclopoid copepods. This phase of diel vertical migration lasted for c. 4 weeks until the burbot larvae suddenly disappeared from the pelagic zone. This indicated a short phase, lasting only a few days, of larval settlement into profundal benthic habitats. This was supported by a significant, abrupt decrease in the absolute growth rates of the larvae at day 56 after hatching. The day-night pattern of vertical migration observed could be assumed to be a transition phase from a pelagic to a benthic lifestyle, as reported for juveniles of several other, marine gadoid species. © 2004 The Fisheries Society of the British Isles.