Where are we now? May 2021 – Part 1: Between a Rock and a Hard Place

Introduction

As at May 2021, the short answer to the question asked in 2018: “How far have we got?  Considering our options in securing the future of the Suffolk Punch  in the United Kingdom?” is simply:  between a rock and a hard place.

There are unavoidable facts and figures whose confrontation can no longer be postponed or put in the ‘too hard basket’.   

Is this the last Suffolk Horse Generation in the United Kingdom?

In 2017 the Rare Breeds Survival Trust UK (RBST) forecast that without major efforts, the Suffolk Horse would be genetically extinct by 2027.

As a horse generation is generally regarded as seven years, then there is only six years and six months left of the last generation of Suffolk Horse in the United Kingdom before genetic extinction by 2027. 

If the safest earliest time to cover a mare is at three years of age and with successful foaling the following year, then four years unimpeded by untoward events is essential.

 

In its ‘Watchlist’ the Rare Breeds Survival Trust UK has consistently rated the Suffolk Horse Breed as Critical – Critically Rare and Endangered.    Perhaps we have become complaisant – as in ‘things will work out’.

This year’s RBST ‘Watchlist’ is different:

“RBST has 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.”

now it has three plain-speak Categories for a United Kingdom native breed.

The incorporation of measures of inbreeding gives an all important mechanism to our understanding of just how desperate is the survival of this breed of draught horse.  https://www.rbst.org.uk/watchlist-overview  

The Critical Nature of Effective Population Size – Ne

 

An understanding of Effective Population size is essential in understanding why The Suffolk Horse herd in the UK has failed to gain ground.     The following paragraphs are from UK Farm Animal genetic Resources (FAnGR) Breed Inventory Number of pedigree animals 2019 (revised to include stocks of cryogenic material), as of 8 October 2020.   Refer also to Figure 1 above which is derived from data obtained from UK Farm Animal Genetic Resources (FAnGR) Breed Inventory 

‘Effective population size is a calculation which takes account of the total number of animals in a population and the relative number of sires and dams (male and female parents).  

A low effective population size signifies a greater likelihood of inbreeding and risk of loss of genetic diversity. A larger effective population size implies a lower risk of inbreeding and higher genetic diversity.’

 ‘The United Nations Food and Agriculture Organisation (FAO) recommends a minimum effective population size (Ne) of at least 50 individuals to reduce the rate of inbreeding to less than 1% and ensure the long-term survival of a breed.’

‘…. Since 2001 when it joined the indicator, the Suffolk Punch has had an Ne of less than 50 every year but one (2009, when the value was 53)’

How does the Effective Population Size (Ne50) of the Suffolk Horse compare with the other two native breeds of Draught Horse – the Clydesdale and the Shire?

In one word – appallingly.   Figure 2 below provides a sobering reminder that although the category of Suffolk Horse is Priority, the Clydesdale and the Shire are At Risk.

And native breed Ponies?

With the grim exception of the Eriskay Pony, and the Hackney Pony https://www.rbst.org.uk/hackney-horse-and-pony, the Suffolk Punch has the unhappy distinction of having the third lowest Effective Population Size of eleven native breed draught horses and ponies.

The current Population of Suffolk Horses in the United Kingdom

Without accurate returns to the Society, exact figures – for a given date in any year – are very difficult to ascertain.   Think of the human population census – it always has a day/month/year date.    We need the same degree of accuracy for our registered horse population.     

Owners and breeders of a rare and critically endangered breed have a responsibility to promptly supply information to the breed association  on matters relating to their horses.   Some owners and breeders take this duty serious, while others appear less than diligent

Every year the Suffolk Horse Society issues a proviso on the published  UK Suffolk Horse Population  – “NB:  These figures are dependent on owners notifying the Society of losses”.

The 2021 Spring Issue, Number 104 of the Suffolk Horse Magazine, page 9, contained a short, but illustrative request by Jessica Ellis, Administrative Secretary at the Society.  It clearly  details a major problem in compiling essential data. 

‘In February 2020, we wrote to over 296 Suffolk Horse owners enclosing the 2020 Suffolk Horse Society census.  

‘… We have had 68% reply to the census to date and are still trying to contact the remaining 93 owners that we haven’t had a response from.   Many of these have either moved house, or may have sold their horse, or the Suffolk has died.   It is so important we contact every so that we can get a true reading of Suffolk Horse Numbers………..

‘…..If you own a Suffolk horse and haven’t completed a census, or know  of any horses within your surrounding area that may not be registered, please let us know.   We currently have 45 Suffolk horses that need to be traced as when they were sold the new owners didn’t contact the Society to update the details on our system.    It is a legal requirement to keep us updated on any transfers or deaths of a Suffolk Horse.

’Suffolk Horse Census by Jessica Ellis (Admin.Sec. Suffolk Horse Society) Suffolk Horse Magazine, P9, Issue 104 Spring 2021

The Total Population is not an indicator of the reproductive ability of a breed.

‘Conservation geneticists’ view is that the UK Suffolk breedable herd is dangerously small.  It has insufficient stallions and mares for genetic diversity, and this has been the case for many years.   This is a view that is shared by some members and supporters of the Society. It is the breeding of horses which determines if any breed of horse survives, not the overall population, which contains old horses, geldings, fillies and colts too young to breed.’ https://suffolkpunchaustralia.com/index.php/clock-ticking-part-2/how-far-have-we-got-considering-our-options-in-securing-the-future-of-the-suffolk-punch-in-the-united-kingdom/

This is why the 2021 new Effective Population Size (Ne) is so important.

Attrition Rates – The Drivers of the 2027 forecast extinction

The smaller the total population of a breed, the greater the impact of ‘normal’ attrition rates contributing to the low Effective Population Size.   

Attrition rates are several and varied, and include, but are not limited to:

        • death (from all causes)
        • not all stallions and mares, capable of being bred,  are used
        • the variable ratio of fillies : colts in some years  
        • the ratio of mares covered to actual foal production 
        • the percentage of Licensed Stallions not used for breeding
        • the none-semen harvesting of Licensed Stallions who are subsequently castrated
        • small numbers of breeding animals, with the resultant loss of diversity.    

Diversity is also lost by a decline in:

        • fertility
        • fecundity
        • continuing over-reliance on the use of Elite Sires.   
More detailed analyses on Attrition Rates and other matters follow with Part 2 of this Article:    See:  https://suffolkpunchaustralia.com/six-articles-on-the-status-of-the-suffolk-horse/where-are-we-now-may-2021-part-2-more-rocks-difficult-terrain/

© Eleanor Yvonne Hatch, Suffolk Punch Australia 2021