Growth and Recruitment of Burbot (Lota lota)

• Main Authors: Jakob Kjellman, Universität Konstanz
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2003
• Subjects: Burbot; Lota lota; lota
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.615.4497; http://ethesis.helsinki.fi/julkaisut/maa/limno/vk/kjellman/growthan.pdf

The aim of this study was to detect factors that influence the growth and recruitment of burbot (Lota lota). The recruitment of burbot is generally determined during the pre-juvenile period. The driving forces behind this early determination of the year-class strength are biotic and/or abiotic. The biotic mechanisms are often grouped into two major hypotheses: starvation and predation, where density-dependent effects during the pre-recruit phase may attenuate recruitment variability. In addition to these general recruitment hypotheses, the River Kyrönjoki forms a special case, since the river is episodically acid. This acidification is so severe that its effects upon the fish population dynamics must be considered if the effects of other variables are to be studied. For fisheries management, concern about recruitment and stock continues to be the ultimate problem. The burbot population abundance off the River Kyrönjoki was the largest at the beginning of the study period. Due to several acid periods during the early and mid-1980s, the population decreased to a