The role of individual behavioral traits on fishway passage attempt behavior

<p>Variations in behavioural traits are widely recognised to drive animal behaviours exhibited within a population. However, information on how behaviour traits influence behaviour in anthropogenically modified habitats is lacking. Many habitats have become highly fragmented as a result of human processes. To mitigate this and improve habitat connectivity, wildlife passes are increasingly employed, with the aim of enabling animals to move freely between habitats. However, wildlife passes (e.g. fishways) are not always effective in achieving passage and it remains uncertain what factors play a role in an individual's likelihood of passing successfully. This study measured three behavioural traits (boldness, exploration and activity) in juvenile brown trout (<i>Salmo trutta</i>; <i>n</i> =78) under field conditions within a river, and tested whether these behaviour traits influenced both the passage success and the behaviours exhibited during upstream fishway passage attempts. Although behavioural traits were found and collapsed into two behavioural trait dimensions, behavioural traits had low repeatability and so did not contribute to a personality spectrum. Boldness was found to negatively influence the number of passage attempts carried out by an individual and to positively influence passage success, with bolder individuals carrying out fewer attempts and having an increased probability of passage success. No behavioural traits were found to be related to other passage metrics (passage success, time until first attempt, and passage duration) during the first passage. But all three behavioural traits were significantly negatively related to the changes in passage behaviours at consecutive, successful passage attempts, with bolder, more exploratory and more active individuals passing through a fishway quicker on the second passage than on the first. This study suggests that bolder and more active individuals may perform better during fishway passage attempts, particularly within rivers where multiple barriers to movement exist.</p>