Foraging specialisms influence space use and movement patterns of the European eel Anguilla anguilla

A fixed receiver array was used to examine the movement patterns and space use of the European eel Anguilla anguilla in an oligotrophic Irish lake between July and September. We assessed home range size, temporal change in spatial behaviour and activity patterns of broad-headed (n = 11) and narrow-headed (n = 8) morphotypes. Broad-headed individuals displayed a larger home range (mean KUD₉₅ (km²):0.296 ± 0.04 S.E.) in comparison to narrow-headed individuals (mean KUD₉₅ (km²):0.143 ± 0.02 S.E.). Eel activity was strongly dependent on light conditions. Narrow-headed individuals’ movement peaks occurred at dawn and dusk in comparison to broad-headed individuals which exhibited a more stable movement pattern throughout night and into dawn, suggesting that narrow-headed eels are more crepuscular in nature whereas broad-headed individuals are more nocturnal. Lunar phase period also influenced eel movement within the lake. These results provide valuable insights into the spatio-temporal distribution of yellow eels in a lake system, demonstrating that individuality in foraging behaviour has direct influence on spatial patterns.