Deer are inquisitive animals and fallow in particular seem to have a penchant for ingesting unsuitable items. In deer parks and around picnic spots remnants of meals discarded by the public can attract these animals to scavenge in the litter bins. While eating apple cores, bananas skins, bread and other organic matter the odd piece of cling film or polythene bag may also be ingested. However, it is hard to see why some animals ingest so much polythene or other forms of plastic and miscellaneous “foreign bodies” which can be of no nutritional value to the deer but unfortunately are very common in the countryside. What can possibly induce an animal to repeatedly ingest rubbish?

The items recorded include balloons, ribbon, silver paper, sweet wrappers, cigarette ends, orange peel, bones and disposable panties but the commonest items are various forms of polythene and string. The conglomeration of items in the rumen are called stringballs. In Belgium fatalities have been reported from this cause but at least two captive fallow were saved by surgery (Audenaerde 2004). I have found several examples during post-mortem examination of fallow deer and I am grateful to observant stalkers who have sent their findings to me.

The appearance of the foreign matter varies according to how long it has been in the rumen. The composition of freshly ingested items is recognisable but after an unknown period of time they become hard, often nodular and look rather like objects deposited in a petrifying well. Often items are twisted rope-fashion, presumably as a result of the churning movements within the rumen. Small foreign bodies might possibly pass from the rumen into the reticulum, the second and much smaller chamber of the stomach, and could form a blockage there but if a large mass accumulates in the rumen it remains there and reduces the volume of vegetation that can be taken in during a feeding bout.

The incidence is doubtless widespread. I know of examples from Ireland, Dorset, Hampshire, Kent, Surrey and Sussex and especially in Suffolk. Five successive bucks culled in NW Suffolk all had knotted binder twine in the rumen and one also had a mass of camouflage netting (Rose 2005). A buck in the King’s Forest had an assortment of strings, polythene bags and black plastic. Washed free of the adhering vegetation fragments and dried this weighed 94g. A few miles away one pricket had a similar but smaller amount of rubbish but another, shot close by on the same day in October 2006, had a huge mass of polythene of six different colours all inter-twined with orange plastic binder string, making it impossible to separate the items even after thorough washing and drying, when the mass weighed 460g (see photo below). In the fresh state with clinging and trapped fragments of leaves it was several times heavier. At this time the animal was still in a good condition but in time such a large stringball would have had a deleterious effect.

A young stag from NW Suffolk is one of the few red deer to be reported with a stringball (Rose 2005). I have never found any in some dozens of roe deer stomachs examined or in hundreds of muntjac and know of no reports for these two species. Ingesting rubbish is just one way in which discarded items can be damaging to deer. String and netting can become wrapped round antlers or caught in the hooves, seriously incapacitating the animal. Those who thoughtlessly dispose of such things do not realise the potential consequences.

References Audenaerde P. (2004) Plastic in fallow deer rumens. Deer Farming. No.79 p.30 Rose, H. (2005) Rural Rubbish Deer 13 (7) 30-31.