New Paper: An Evaluation of canes as management technique to reduce predation by gulls on ground nesting seabirds

Boothby,C., Redfern, C. & Schroeder, J. 2019. An evaluation of canes as management technique to reduce predation by gulls on ground nesting seabirds. IBIS. DOI: 10.1111/ibi.12702.

Arctic Terns by Chantal Macleod-Nolan

A paper was published in 2018 which investigated how effective the presence of canes was in an Arctic tern colony to deter gulls. This pilot experiment was undertaken at the National Trust’s Farne Islands. Four sites across two islands (Inner Farne and Brownsman) were separated into three treatment areas: no canes, low density cans (2m apart) and high-density canes (1 metre apart). The results revealed that the canes did act as a deterrent with the caned areas receiving less than half of the number of predation attempts compared to the control area (no canes). Interestingly though, there was not a significant difference between the two cane densities.

At the beginning of the study, the hypothesis was that canes may impede the ability of large gulls to successfully take Arctic Tern Sterna paradisaea eggs or chicks. However, although the canes seemed to act as a deterrent to predation attempts, when birds ignored the canes and tried anyway they were just as successful as in the areas without canes. In short, canes seem to deter the gulls from trying, but those that did try were just as likely to be successful as in the control areas. 
  
Further research is needed to support these findings but as the canes are of minimal cost and easy to set-up, this pilot study indicates that they could provide a useful and versatile tool for conservation managers. 

This information came from the summary written by Claire Boothby in the link below. 
https://www.bou.org.uk/blog-boothby-gull-predation-deterrent-seabirds/