U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Date of this Version



International Journal or Pest Management Vol. 57, No.3, July-September 2011,189-193


Design of selective bait stations to deliver rodenticide bait is often proposed for management of non-target animal access, but much of the information on the behavioural and physical capabilities of rodents relative to station access has not been readily available or is based on unpublished, informal observations or anecdotes repeated for many years. We studied the climbing and jumping abilities of Polynesian Rats (Rallus exulans), Norway Rats (R. norvegicus), Roof Rats (R. rallus), and House Mice (Mus musculus), focused on applications for eradication of these invasive rodents from island ecosystems in the Pacific where a variety of important non-target animals occur. The maximum jumping heights achieved by the three rat species was 40 cm; House Mice jumped a maximum of 25 cm. The minimum diameter holes through which these species could pass were 40 mm (Norway Rats), 35 mm (Roof Rats), 30 mm (Polynesian Rats), and 13 mm (House Mice). Our findings establish threshold differences for these species for transiting access openings or jumping to platforms to obtain food. In areas where endangered birds or other animals occur, such information could be used in designing selective stations so as to prevent unnecessary poisoning.