With a height at the shoulders of about 110 cm the Chillingham Cattle Bos taurus are small animals. Their general body conformation is that of late medieval cattle prior to the era of agricultural improvement, being relatively long in the leg and short in the body; this proportionality, coupled with their impressive horns (carried by both sexes) makes them appear larger than they actually are. Their white coloration and red ears make them very distinctive.
In the early 20th century animals from Chillingham contributed to other parkland herds of horned white cattle (Whitehead, 1953) and these were ultimately combined to form the White Park breed which is a much larger animal with, essentially, the body conformation of a 19th-century beef breed. None of these other parkland herds have the same history of unbroken residence in an ancestral range.
No bulls are castrated. Cows calve all year round, though a tendency to conception earlier in the spring, as a response to climate warming, has become evident (Burthe et al, 2011). Bulls compete for matings during all seasons and display, dominance and fighting behaviours are very prominent in the life of the herd. Traditionally a “king bull” system was said to operate and while this may well have been the case at some times, it is not always evident, and bulls appear to exhibit a degree of home-range behaviour, while cows and young animals roam the 134 ha Park as a single herd, or as smaller sub-herds.
Between 1977 and 1982 the average age of cows at calving (generation interval) was 7.2 years. The mean time between calvings was about 450 days, the 280 days gestation period implying that on average cows conceived nearly six months after calving. The removal of the sheep flock would be expected to promote herd growth as a result of reduced nutritional competition. Equal numbers of male and female calves are born but survival rates of males are lower at all ages, so herd sex ratios have usually been female-biased. This has changed recently with the current sex ratio of the herd being approximately 50:50. Also indicative of improved nutrition is better body condition of individual animals. Prior to the removal of the sheep the usual weight for a mature animal in winter (recorded at autopsy as thin, but not emaciated) was 300 kg for bulls and 280 kg for cows, but a bull culled for welfare reasons in 2012 (battle damage) was found to weigh 400 kg.
Maximum ages attained by bulls and cows are probably 9 and 12 years respectively though the lack of ear tagging means this cannot be verified. Calving problems, at approximately one in 70 pregnancies, were much rarer than in commercial cattle perhaps partly because age at first calving was usually three or four years (Hall and Hall, 1988). Age at first calving is probably declining now (a heifer, euthanized for welfare reasons in January 2012, was showing an ovarian follicle at 10 months of age) and this could result in an increase in difficult births.
Mortality of young calves, particularly during the first 30 days, can be quite high in a bad winter and sometimes abandoned calves have been removed and taken to the reserve herd, but these efforts are often unsuccessful. Normally the cow calves away from the herd and she visits the calf periodically to suckle it. After some days the calf will follow its mother back to the herd and other cows are usually very interested in the new arrival. The traditional story of the new calf being inspected and either accepted or rejected presumably arises from this behaviour though outright “rejection” by other cattle has seldom, if ever, been reliably recorded.
Hay is taken to the herd in the winter, the date that feeding starts depends on the evident appetite of the animals. Now that sheep are no longer kept in the Park forage is relatively abundant until winter is fairly well advanced. Apart from hay feeding little intervention is practised though individuals are sometimes euthanized on welfare grounds (Hall et al, 2005). Autopsies are performed if there is any doubt about cause of death but the cattle are apparently free of the notifiable infectious diseases. Given their genetic uniformity, which would tend to make them relatively susceptible to disease, this freedom is probably due largely to their isolation and the biosecurity measures in force.
The herd gives the opportunity of observing the behaviour of cattle relatively free of human interference and it is one of the very few such herds anywhere in the world and the only one to have been studied in detail. In the past observers have been able to identify animals individually (they are not ear-tagged) and it is clear that the detailed behaviour patterns of bulls and cows differ markedly. For example periods of grazing and ruminating tend to be shorter for bulls than for cows during daytime but not at night. These sex differences are apparently because bulls have to be permanently on the lookout for rival bulls or for cows coming into season (Hall, 1989).
Chillingham cattle are far more vocal than husbanded cattle and bulls have distinctive calls (a repeated, high pitched hoot, not reported in cattle elsewhere) and lowing sounds, while cows perform the familiar “moo” call (Hall et al, 1988). Both sexes spend a lot of time scratching against objects and this behaviour, when performed by bulls, may have a social display function. Bulls also paw the ground and rub face and neck in the earth. These behaviours can be seen throughout the year, the intensity being greatest when a cow is in season. Some behaviour, notably the cow-cow mounting so frequently observed in oestrous dairy cows, are of vanishingly rare occurrence at Chillingham.
Mechanisms underlying change in numbers are not easy to elucidate because the small herd size means random factors can be important. Also, hay feeding shelters the herd from many of the effects of a harsh winter. Some mortality and fertility factors may respond to the size of the herd (in the period 1953-1985 mortality rates of adults increased as herd size increased: Hall and Hall, 1988), while there may also be an effect of winter weather, in that the North Atlantic Oscillation index appears to influence overall herd growth rate (calm, dry and cold winters may be favourable, while windy, wet and warm winters may be detrimental: Hall, in preparation). However, with reliable herd records dating back to 1945, it should be possible to find which factors have been most important, though as is normal with wild populations, prediction of numbers will probably not be reliable.
Removal of the sheep has enabled conservation of the Park as a complete environment to be managed more than was previously possible. The Park, the surrounding woodlands, and the cattle are now all the property of the Chillingham Wild Cattle Association, after a period of separate ownerships. With generous support from individuals, trusts and support received from the DEFRA Higher Level Stewardship Scheme, the biodiversity and cultural value of the Park is being protected and enhanced as the only parkland environment in Britain inhabited by an eponymous breed, and with both trees and pastures in relatively good condition. More information and news about the herd and park can be obtained from the Chillingham Wild Cattle Association.
Written by Stephen Hall (last updated Nov 12)