Animals (livestock)

• Feed availability
• Water Quality
• Seasonal Influences
• Ash toxicity
• Other factors
• Evacuation of livestock

Livestock face risk from both falling and deposited volcanic ash. They are susceptible to a wide variety issues, predominantly from water and feed supply shortages leading to livestock dehydration and starvation. Other issues include:

• Inhalation and respiratory discomfort
• Eye and skin irritation
• Abrasion of the teeth and hooves
• Ingestion leading to gastrointestinal blockages
• Fluorosis

These can become issues with minimal ash coverage levels. There is a greater impact on soil grazing livestock such as sheep and deer compared to that of higher grazing animals such as cows (Wilson, 2007). These effects each depend on (Neild et al., 1998; Cronin et al., 1998; 2003; Wilson, 2007):

• Ash characteristics (grainsize, composition, presence of poisonous aerosols)
• Rainfall and windfall before and after ashfall (to aid in the removal of ash from food source).
• Species and age of the livestock
• Nutritional demands of the livestock at the time of ashfall
• Pasture length
• Stocking rate