An accessible scheme for monitoring free‐roaming cat population trends

Abstract

Free‐roaming cats (FRCs) form nondomiciliary population groups that might lead to adverse environmental effects, as well as to welfare impairment of the cats themselves. Though criticized by ecologists, for the last two decades, the trap–neuter–return (TNR) programs were often employed aiming to manage these populations. At present, no accepted and accessible monitoring scheme exists to determine the effectiveness of those programs. In the current study, we present the reliability and validity of an applicable monitoring scheme, as an adjunct tool for a TNR program of FRC in an urban environment. The monitoring scheme is based on cat observation counts along randomly chosen transects. Fifty‐four transects were repeatedly walked for three years, between 2012‐2014, in 27 neighborhoods within an urban area of 19.3 Km2. Cat numbers counted in the 2014 observations were significantly higher than cat numbers found in the 2012 observations (prevalence ratio = 1.258, CI95%= 1.198–1.322, p < 0.001). The method revealed high reliability when different observers and different transects in the same neighborhood were compared (R2 = 0.548 and R2 = 0.391, respectively, for measuring cat counts per km, p < 0.001; and R2 = 0.5 and R2 = 0.74, respectively, for measuring neutering percentage, p < 0.001). This scheme was constructively validated by measurements of municipal data on the number of neutered cats and demonstrated high correlation (R2 = 0.59, p < 0.001). Conducting cat observations using friendly calling and feeding resulted in an increased number of FRC observed per km walk (by 79% and 22%–30%, respectively). However, these manipulations did not alter the recorded percentage of neutered cats. The proposed scheme provides spatio‐temporal data that can contribute to the management programs of such cat metapopulations in an urban environment.

Reduction of free-roaming cat population requires high-intensity neutering in spatial contiguity to mitigate compensatory effects

“…This observation was probably due to the growing proportion of neutered shy cats as the neutering percentage increased (79). Hence, we assume that our estimations of neutering intensity are reliable and valid and thus enable robust evidence for TNR effects and limitations.…”

“…The total length of the transects was 100.87 km ( Figure S3 ). A comprehensive description of this sampling method, including its intra-observer, inter-observer, inter-transect agreement, and validity, is detailed in Gunther et al 2020 (79).…”

Domestic Cat Abundance and Activity Across a Residential Land Use Gradient

“…Because vital rates in these models may be constrained by estimated carrying capacities, inaccurate abundance estimates can yield unrealistic outcomes. Moreover, accurate count data are necessary for monitoring the efficacy of management programs following implementation (Gunther et al, 2020). Our results suggest that future efforts should account for predictors of cat abundance, such as human population density and socioeconomics, to estimate model parameters.…”

Reduction of free-roaming cat population requires high-intensity neutering in spatial contiguity to mitigate compensatory effects

“…Moreover, the mean insignificant increase by 18% (from 46 to 56%) of neutering percentage diminished almost completely when the neutering percentage was high (above 74%). This observation was probably due to the growing proportion of neutered shy cats as the neutering percentage increased ( 81 ). Therefore, despite the inherent uncertainty in the number of neutered cats not seen by the observers, we assume that our estimations of neutering intensity are reliable and valid and thus enable robust evidence for TNR effects and limitations.…”

“…A comprehensive description of this sampling method, including its intraobserver, interobserver, intertransect agreement, and validity, is detailed in Gunther et al. ( 81 ).…”