The short answer is almost anything! We have been using young Exmoor ponies at Llyn Llech Owain, for conservation grazing, since June 2006 and during this time we have gained some insight into the eating habits and preferences of this ancient eco‐natural race. The ponies spend the autumn on the lowland heath areas, moving onto a steep bracken clad slope, which has not been grazed since the 1970’s, in November.
Detecting ponies’ food preferences, by observation alone, is difficult, especially in a mixed sward, as it is impossible to determine what each 10g mouthful contains. Faecal analysis, for plant fragments, is the established method of determining the accurate composition of the diet. Being a successful conservation grazing manager involves a rather unhealthy interest in dung! However a less scientific approach is possible in late autumn and winter, when the range of vegetation is more limited. This relies purely on regular observation of grazing and browsing ponies, vegetation abundance and close examination of yes you guessed ‐ changes in dung colour, consistency and contents. Free ranging Exmoor ponies may dung up to 17 times per day so there is always plenty of reference material....
Exmoor ponies can eat 2.5% of their body weight per day. They are monogastric ‘trickle feeders’, which have evolved to feed on poor quality vegetation for up to 18 hrs per day. The ponies have to graze and browse for long periods during the winter due to the lower nutritional value of the vegetation and also the greater need for calories. Like all native ponies they have a strong preference for a grass‐based diet and are frequently chosen for grazing sites like this with excess rank grasses such as purple moor grass (Molinia caerulea). The ponies also select non‐grass species through necessity, but also to add variety to their diet. Exmoors’ are opportunist feeders eating mosses, sedges, rushes, small quantities of heather, bracken, leaves from deciduous trees, small forbs, bramble, gorse and holly in the absence of their preferred grass species. It is accepted knowledge that ponies have an advanced ability to differentiate between plants and some people claim they also have an ability to recognise the nutritional and medicinal values of plants, trees and shrubs.
Getting their ‘5 a day’
In the autumn the colour of the dung, and the stones and seeds it contains, indicates that the ponies exploit the abundance of berries and fruit on the heathland. They readily take blackberries, bilberries, haws, elder berries, crab apples and rosehips. Browsing scrub and heath‐land shrubs
The ponies are primarily grazers but also have a role managing scrub areas, having a two fold affect; browsing on selected species and also trampling and dislodging encroaching scrub. Most browsing, considered a learned behaviour, occurs with the decline of grass species in the autumn and winter and is an important element of the winter diet. The ponies nibble gorse (Ulex species), bilberry (Vaccinium myrtillus), heather (Calluna vulgaris), willow (Salix) species, and bramble (Rubus fruticosus). Birch (Betula species), rowan (Sorbus aucuparia) and oak (Quercus) leaves, twigs and bark are also taken but fallen ash (Fraxinus excelsior) leaves are the most favoured delicacy in the autumn. The ponies ‘hoover’ them up by sucking in whilst moving their head rapidly from side to side and the dung is noticeably darker in colour from the tannins.
Food processing of prickly vegetation
The Exmoors’ resort to food ‘processing’ less manageable vegetation, when grasses are in short supply. They have been observed pawing at and trampling gorse (Ulex gallii), to ‘soften’ it, before consuming. The ponies also harvest holly leaves, cutting and discarding small branches and then allowing them to wilt for a few days before consuming them. The Exmoor has a toughened tongue, a hairier upper lip in winter and has developed careful eating techniques to cope with ingesting prickly vegetation.
Bulbs and roots
Primitive ponies have the ability to utilise roots, bulbs and rhizomes e.g. bracken (Pteridium aquilinum), bramble (Rubus fruticosus), stinging nettle (Urtica dioica), meadow thistle (Cirsium dissectum) and rushes (Juncus species) are all dug up and eaten.
Grazing ponies generally avoid eating the flowers of flowering plants. However, our Exmoors’ seem to make an exception for knapweed (Centaurea nigra) and rosebay willow herb (Chamerion augustifolium ) which they find highly palatable, even in late autumn.
Grazing purple moor grass (Molinia caerulea)
Exmoor ponies preferentially graze purple moor grass (Molinia caerulea) during the autumn and the straw (feg) during the winter, when it could constitute up to 20% of the diet, although the nutritional value must be negligible. The ponies also dig up and split tussocks of purple moor grass looking for green shoots inside the clump. When first put out on the ‘Bracken Bank’ they closely crop the limited areas of perennial grasses, growing along the hedge banks, before moving onto the few areas of lush great wood rush (Luzula sylvatica). The grazing of the wood rush produces vibrant green dung. Only when both these sources of food have been diminished do the ponies move onto the purple moor grass, mosses and other less favoured vegetation.
The ponies spend several winter months on the north facing bracken slope. The aim is to reduce the dominance of bracken (Pteridium aquilinum) on this SSSI and S.A.C. and allow heathland vegetation to re‐emerge.
The ponies trample the dense bracken litter and the rhizomes. The herd is encouraged to trample systematically by feeding hay, spread out daily on the worst affected areas. Spreading out the hay also satisfies the ponies need to forage and walk and feed simultaneously. Supplementary feeding also allows them to stay out on the bank, in sometimes inhospitable conditions, when there is limited vegetation available.
Although it may cause poisoning, and vitamin B deficiency, bracken may also constitute approx.1 % of the free ranging Exmoor pony’s diet. Bracken contains thiaminase, which destroys the animal’s thiamine (vitamin B1), which can lead to myelin degeneration of peripheral nerves. Breeders believe that experienced ponies should 'know' not eat the bracken, particularly before the toxicity has declined in early autumn, when they may take it when forage is scarce. Our grazing ponies are excluded from the densely bracken covered areas between early spring and early autumn purely as a precaution.
Maintaining a 365 day grazing scheme, on existing Molinia dominated habitats at Llyn Llech Owain, without access to layback land between January and April, will continue to be a challenge into the near future.