The 'STRAYS' Project

A scientific project to determine the sustainability, effectiveness and efficiency of stray dog population management methods


Stray dog overpopulation is a global concern with implications for public health and safety, environment protection, wildlife conservation, as well as animal welfare. Irresponsible pet ownership (e.g., abandonment) and lack of birth control programmes lead to an increase in stray dogs. In high numbers, stray dogs can contribute to spreading diseases, cause human-animal conflicts (e.g., bites and traffic accidents), threaten the survival of other species of animals, cause economic burdens (e.g., costs associated with management, rabies vaccination), whilst often experiencing health and welfare problems themselves.

The STRAYS project was developed by the University of Leeds, FOUR PAWS International, and IZSAM (Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise 'Giuseppe Caporale'), with the aim to determine the most sustainable, effective, and efficient method of managing the number of stray dogs. Please find our publications and studies about stray dogs here.

STRAYS PhD Research

The STRAYS Project was structured as an academic PhD research and involved collecting data on dog populations from two study sites (Lviv, Ukraine and Teramo, Italy) and on public attitudes towards stray dogs using online surveys (in Italy, Ukraine, and Bulgaria). Stray dog population size, financial costs, welfare impact on the dog population and impact on public health are some of the factors this study considered when comparing different dog population management methods (catch-neuter-vaccinate-return, long-term sheltering, and mass culling). Collected data was used in statistical modelling to determine long-term effectiveness in humanely reducing population size.

Need to target sources for stray dog population increase

The key result of the STRAYS project is that methods targeting multiple sources of population increase, (i.e., reducing births in the free-roaming dog population, abandonment of dogs, and allowing owned dogs to roam) are most effective at reducing free-roaming dog population size, whilst also being cost-effective and improving dog health and welfare. Furthermore, neutering interventions applied continuously (monthly) and covering a high proportion of the population (i.e., >65%) will increase effectiveness and efficiency overall. Mass culling and long-term sheltering do not offer a sustainable solution to stray dog overpopulation, as they do not address the causes for population increase. It is important to also consider public attitudes towards stray dogs and dog ownership practices to adequately tailor responsible pet ownership campaigns.

CNVR & Responsible pet ownership education have the biggest impact

Humanely reducing the number of stray dogs through catch-neuter-vaccinate-return (CNVR) campaigns coupled with responsible pet ownership education represent together the most effective, efficient, and sustainable technique to reduce stray dog population size, while ensuring animal welfare and reduced costs.

Why mass culling and long-term sheltering are not effective and sustainable solutions

Removal of stray dogs from the streets, either by culling or long-term sheltering does not address the sources of population increase. Removal only creates a temporary vacuum in the population that is quickly filled in by other individuals, either through births, immigration from neighbouring areas or through pet abandonment.

Ukraine, Bulgaria, Italy: attitudes towards stray dogs

Ukraine, Bulgaria, Italy: attitudes towards stray dogs

© 2022 Smith et al. This online questionnaire study aimed at determining the humans’ attitudes towards free-roaming dogs and the dog ownership practices in Bulgaria, Italy, and Ukraine.

Review on dog population management methods effectiveness

Review on dog population management methods effectiveness

© 2019 Smith et al. This review systematically reports about the current research investigating the effectiveness of different dog population management methods.

Using a system dynamics model for free-roaming dog population management assessment

Using a system dynamics model for free-roaming dog population management assessment

© 2022 Smith et al. This paper presents how to model which dog population methods are the most cost-efficient, effective one and involves a high level of welfare.


Help for Stray Animals

Worldwide projects to help stray dogs and cats 

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