Electronic sheep reveals how extreme weather affects flocks

Two electronic ewes fitted with a battery-powered heating system have been stationed at Bangor University's research farm in North Wales.

The digital animals are dressed in thick fleeces and equipped with ear tags and woolly tails, looking just like their real-life counterparts. The heating system simulates the heat a real animal would produce when exposed to various weather conditions. The researchers can then measure how much energy the animal needs to spend to handle the thermal stress.

The goal of the study is to find whether some simple solutions - such as hedges and rows of trees - could help reduce the weather-related strain on the animals.

"Sheep use a substantial amount of energy just staying warm and lose a lot of heat when it's cool, especially when there's a wind chill,” said Bangor University PhD student Pip Jones.

"On a hot day when the weather was around 30°C at the study site, we put a model sheep in the direct sun and the fleece recorded a temperature of 60°C, which is incredibly hot. This is where the shelter of trees could really contribute, creating shade in the summer and reducing the effects of wind chill in winter."

The researchers know that dealing with extreme weather stress affects not only the animals’ comfort but also their growth and food consumption.

"If it's very cold a sheep burns more energy to keep warm for survival and it needs more food,” said Andy Smith, senior lecturer in forestry at Bangor University.

"Conversely, if it's too hot, animals tend to eat less and seek shade to keep cool. Both situations affect weight gain and productivity because energy that could go into growth is used to regulate metabolism instead."

Young lambs in particular are at risk of hypothermia in winter months, while adult ewes could develop mastitis in adverse weather conditions. Planting tree shelters could help protect the animals and also improve drainage and fence sheep off from wet areas where fluke parasites thrive.

The study, funded by the Woodland Trust, hopes to provide farmers with advice on how to protect their flocks in order to increase farm profitability and efficiency using sustainable methods.