What is ‘wallowing’?
Wallowing is where deer bathe and roll around in mud. They create wallow sites in wet depressions in the ground, eventually forming quite large sites (2-3 metres across and up to 1 metre deep). These sites tend to be used by most members of the herd at some stage, although access can be hotly contended on some occasions. It is not uncommon to see deer walking around caked in mud.

Why do deer wallow?
There are various opinions as to why red deer like to wallow in mud. Some believe it is to control ecto-parasites (ticks and lice), others believe it is to cool down on hot days. However, wallowing behaviour is seen in un-parasitised deer and on very cold days.

It is interesting to observe the behaviour of red deer when entering a new paddock containing a wallow site.  Animals will line up and contest access to the wallow. The ‘pecking order’ soon becomes clear, as the dominant animals gain priority access to the wallow.  See sociability for more information on social hierarchies of hinds. Whatever their reasons for wallowing, red deer love it! It is part of their natural behavioural repertoire.

Do all deer species and breeds wallow?
Only some species of deer wallow; red deer particularly like to wallow but fallow deer, for example, do not wallow. Even within the red deer species, there is variation between sub-species and breeds in wallowing behaviour. For example, although wapiti do wallow, they and crossbreds are less inclined to wallow than European red deer.

When is wallowing a problem?
Wallowing is a problem when it interferes with the farming operation. If uncontrolled, when large wallows drain into catchments, wallowing can lead to contamination of waterways. The wallow sites themselves can become rather barren due to mud caking of surrounding pasture. Also, the stagnant wallows themselves may harbour unwanted pathogens.

Wallows can also present a hazard to farmers, particularly when large enough to cause vehicle accidents.

The consequences of wallowing on the physical features of the deer is sometimes problematic for the deer slaughter premise since mud-caked deer (sent particularly in the Spring) are more difficult to process hygienically than clean deer. Carcass contamination can through pathogens transferred from wallow mud may also lead to meat spoilage.

How can I best manage wallowing?
Wallowing is a natural behaviour, and access to wallows probably improves the well-being of farmed red deer. In fact, it is near impossible to completely deny red deer access to wallows; they simply create them to meet their innate need to wallow.

However, the negative impacts of wallowing need to be mitigated. Minimising waterway contamination is important, and may necessitate creating or encouraging deer to use ‘safe’ wallow sites (i.e. wallows that do not drain into waterways). These can be strategically located out of harm’s way. New wallows may need to be monitored and filled if they present a problem.

  • Sensitive wet sites may need to be fenced off to prevent the inevitable formation of wallows.
  • In respect of sending presentable deer to the deer slaughter premise, it may be necessary to ensure that nearly finished deer are grazed on clean, dry paddocks for up to 2 weeks before despatch.

Show me the science

McDowell, R.W. (2009) The use of safe wallows to improve water quality in deer farmed catchments. New Zealand Journal of Agricultural Research 52: 81-90.