Capture of the North American invasive crayfish Procambarus clarkii by using artificial burrows of preferred sizes

To examine the effectiveness of artificial burrows for eradicating the North American invasive crayfish Procambarus clarkii, we conducted a field experiment of capturing the invasive crayfish in two ponds in the Handayama Botanical Garden, Okayama, Japan, by using artificial burrows of preferred sizes during September to November 2014. We set the artificial burrows, which were made from straight polyvinyl chloride pipes of different sizes, at 15 study stations in the ponds in the late afternoon and then collected them early the following morning. In both ponds, P. clarkii were continuously captured using the artificial burrows during the experimental period and the total number of crayfish captured was 51. Furthermore, two females with 104 and 258 hatchlings, respectively, were captured using the artificial burrows. The body sizes of crayfish captured ranged 8.135.7 mm and 22.7-83. 4 mm in carapace length and total length, respectively, indicating that the artificial burrows of preferred sizes can collect P. clarkii of various sizes. We conclude that the artificial burrows of preferred sizes are effective for capture and subsequent eradication of P. clarkii, including females with hatchlings.