Pesticide usage in Scotland: rodenticide use by local authorities 2015

Executive summary

This report presents the results of a survey of rodenticide use by Scottish local authorities ( LAs) in 2015. Of the 32 LAs contacted, rodenticide use data were received from 25, which collectively represented 81 per cent of the Scottish population.

These LAs used 14.9 tonnes of rodenticide bait in 2015. This bait contained less than 1 kg of rodenticide active substance. The majority of rodenticides were used in domestic settings (11.5 tonnes), with a further 1.2 tonnes used in industrial or mixed industrial/domestic settings. Rodenticide baiting of sewers was reported by only 5 LAs (34 kg). In total, non-agricultural baiting accounted for 12.7 tonnes. Some LAs also conducted baiting on agricultural holdings on behalf of farmers (2.2 tonnes, 15 per cent of total LA use).

Almost all rodenticides used were second generation anticoagulant compounds. The principal rodenticide encountered was bromadiolone, accounting for 84 per cent (12.5 tonnes) of total use. Difenacoum and brodifacoum were the second and third most commonly used rodenticides respectively.

LAs reported that they conducted rodenticide baiting throughout the year (99 per cent), without significant seasonal variation. Wax blocks were the most common type of bait encountered (64 per cent of total use), followed by grain baits (35 per cent). The main targets of LA rodenticide baiting were rats (59 per cent) or a combination of rats and mice (35 per cent).

In addition to rodenticide usage data, LAs were asked about other aspects of their rodenticide use and rodent control. Of the 32 LAs contacted, these supplementary data were received from 29, which collectively represented 92 per cent of the Scottish population. The majority (76 per cent) of these LAs used one or more non-chemical rodent control method. These primarily consisted of break-back traps, but also included live capture traps and glue boards. LAs were also asked about rodenticide resistance, and two LAs reported that they were aware of resistance in their administrative regions.

LAs were asked a series of questions about training and compliance with best practice in relation to rodenticide use. All LAs stated that operatives had received training in rodenticide use. In relation to baiting, 100 per cent of LAs reported that they regularly inspected bait and always protected it from non-target animals. Ninety seven per cent of LAs stated that they always recorded the quantity and location of baits, 90 per cent searched for rodent carcasses and 72 per cent removed bait after targeted baiting periods. The majority of LAs disposed of rodent carcasses in landfill sites, with the remainder reporting a range of disposal methods including burial, incineration and use of waste disposal companies.

These results are discussed in relation to previous Scottish agricultural rodenticide surveys and the last UK local authority rodenticide survey. This is the first Scottish LA rodenticide survey. It is intended that, in future, these surveys will be conducted every four years.