The 2024-25 Watchlist has been produced using the methodology first used in 2021. RBST reviewed its methodology for compiling the Watchlist. The new approach compares effective population size with measures of inbreeding, moving away from the previous focus purely on female registrations. This gives a more accurate reflection of a breed’s true conservation status. The data used for producing the watchlist is gathered in conjunction with Defra and is obtained from the relevant breed societies.

Press Release: New Watchlist published

Download Watchlist Poster

New Methodology 

In 2021, a task and finish group reviewed methods used to analyse the breed data behind the annual Watchlist to ensure it remains effective for breed conservation. Following the review, its recommendations have been reflected in the presentation of the 2023-24 Watchlist. The review included consultation with the RBST’s Expert Advisory Panel.

The group’s key finding was that the time had come for a significant change in methodology if the Watchlist was to remain a meaningful conservation tool.  Historically, RBST has based the Watchlist on registered females. The concern was that, continuing to base RBST’s conservation programme purely on them, without a consideration of the contribution of males, could result in inaccurate conclusions on the breed’s status.  

The new methodology therefore has two key aspects. Firstly, that prioritisation should be based on the internationally recognised concept of effective population size, which takes into account both the males and females, and secondly, that the degree of inbreeding should be acknowledged.  

The Effective Population Size indicates the genetic diversity within the breed, by accounting for the total number of animals in a population and the relative numbers of male and female parents (sires and dams). A low effective population size signifies a greater likelihood of inbreeding and a higher risk of loss of genetic diversity. 

Accordingly, going forward, a breed of most concern will one which is rare, with increased inbreeding, whereas those of least concern will not be rare and any inbreeding will be well managed.

This new approach has now been applied to breed data from the last twenty years to better reflect longer term trends.

In addition, the Watchlist has, been simplified to return to the more straightforward categorisation used when it was first devised.  Breeds are now either “Priority”, “At Risk”, or a “UK native breed” and the information is presented in a simple, colour-coded format. 

Priority breeds represent those breeds of most concern, which are both rare and have increased inbreeding.

At Risk breeds represent those breeds with lower numbers than ideal and with a degree of inbreeding that gives cause for concern.

RBST Watchlist Methodology

Previous Methodology

The 2024/25 Watchlist has been compiled using the new methodology for calculating breed status. For comparison you can view how the RBST 2024/25 Watchlist would look like using the previous multiplier method to calculate the estimated number of breeding females.

See the Watchlist using previous methodology

Original Populations

For information on "Original populations" and the new methodology visit: Original populations in native livestock

Native Breed Criteria

Any breed wishing to be recognised onto the RBST Watchlist should submit a formal application to RBST. To discuss this further please contact the RBST Senior Conservation Adviser

To download the full criteria, click here.