Pesticide usage in Scotland: Rodenticide use by Local Authorities 2023

Key Points

• This report presents results of a survey of rodenticide use by Scottish local authorities (LAs) in 2023. Data were received from 27 of 32 LAs, collectively representing 91% of the Scottish population. This is the second in a series of LA rodenticide use surveys since 2015.
• Responding LAs used 12.2 tonnes of rodenticide bait in 2023, down from 14.9 tonnes in 2015, These baits contained less than 1 kg of active substance. The majority of rodenticides were used in domestic settings (8.8 tonnes), with a further 1.6 tonnes used in industrial or mixed industrial/domestic settings. No rodenticide baiting of sewers was reported. In total, non-agricultural baiting accounted for 10.3 tonnes, compared to 12.7 tonnes in 2015. Some LAs also conducted baiting on agricultural holdings on behalf of farmers (1.9 tonnes, 15% of total LA use, the same proportion as 2015).
• Almost all rodenticides used were second generation anticoagulant compounds (>99%). The principal rodenticide encountered was bromadiolone, accounting for 9.3 tonnes of product used (76% of total use, down from 84% in 2015). Brodifacoum and difenacoum and were the second and third most commonly used rodenticides respectively, with their relative importance reversed compared to 2015.
• LAs reported that they conducted rodenticide baiting throughout the year (99%), with little seasonal variation. Wax blocks were the most common bait type encountered (49% of total use), followed by grain baits (43%), a change in relative proportions from 2015 (64% and 35% respectively). The main targets of rodenticide baiting were a combination of rats and mice (59%).
• Supplementary data were received from 26 of the 32 LAs contacted, collectively representing 84% of the Scottish population. A majority (80%) of responding LAs used one or more non-chemical rodent control methods, most commonly break back traps. Five LAs reported awareness of issues with rodenticide resistance in their region, up from two in 2015.
• When asked about training and best practice in relation to rodenticide use, all responding LAs stated that operatives were trained in rodenticide use. All LAs reported regular bait inspection and 96% always protected it from non-target animals. Eighty eight per cent of LAs stated that they recorded quantity and location of baits, 88% searched for rodent carcasses and 88% removed bait after targeted baiting periods. The majority of LAs disposed of rodent carcasses in landfill sites.
• Results are compared to LA rodenticide use in 2015, and previous Scottish agricultural rodenticide surveys. This is the second Scottish LA rodenticide survey. It is intended that these surveys will be conducted every four years.