Passive fishing gears, such as hook-and-line angling, are expected to selectively capture fish of certain behavioural types because by definition passive gears exploit fish behaviour. Behaviours increasing angler encounters (e.g., activity or activity space size) and behaviours promoting bites (e.g., boldness or aggression) are good candidates for angling induced behavioural selection, but the importance of specific behaviours is likely a function of a given species‘ foraging mode in light of the lures and baits by which it is targeted. Further, fishing induced behavioural selection is expected to be modified by the searching strategies and techniques of fishers. Our aim was to comprehensively tease apart the role of fish and fisher behaviour as it relates to fish vulnerability in the wild by analyzing long-term acoustic tracking data at a whole lake-scale collected from both piscivorous and omnivorous fishes, viz.: perch (Perca fluviatilis), carp (Cyprinus carpio), tench (Tinca tinca) and pike (Esox lucius). All species were experimentally angled. Direct encounters with anglers and related behaviours including activity, activity space size, or distance to the shore were unrelated to angling vulnerability in carp, tench and perch. Perch preferring a certain habitat (north lake shore) were, however, preferentially captured independent of angler encounters. By contrast, activity space size was a significant driver of vulnerability in pike, supporting the idea that the relationship between fish behaviour and vulnerability is species specific. All behaviours we assessed were repeatable in the wild, such that ultimately our data suggest angling-induced selection targets different behaviours in different species.
Date:
Thursday 15 November 2018 - 14:00 to 15:00
Location:
NOC Southampton - Node Room (074/02) (Waterfront Campus).
Speaker:
Dr Chris Monk, IGB Berlin
Seminar category:
POETS Corner