During winter we set out tracking tunnels, containing ink cards and peanut butter, any ‘fussy rats’ not taking the bait would be detected taking peanut butter and leave footprints. Also our camera traps would get evidence of any activity. After December 2013 we had no sign of rats but plenty of signs of Scilly shrews! Although they feed on insects, it seems they developed a taste for peanut butter! The Scilly shrews seem to have increased since the removal of rats.
