Common Shrew Welfare and Invertebrate Prey Decline

The common shrew is one of Britain most abundant yet least seen mammals, with an extraordinarily high metabolic rate requiring continuous feeding, making its welfare highly sensitive to invertebrate prey availability across all terrestrial habitats.

Key Facts

Common shrews must eat approximately 80 to 90% of their body weight in invertebrates every day to survive
They have a lifespan of only 12 to 18 months, meaning populations turn over completely each year
Shrews have a venomous saliva that can paralyse invertebrate prey
They are not protected and are killed in large numbers by cats, although cat saliva causes fatal shock in shrews
Common shrews produce high-pitched ultrasonic calls used for echolocation in vegetation

Welfare Considerations

Common shrew welfare is acutely threatened by any reduction in invertebrate prey availability. Agricultural insecticide use and habitat intensification reducing beetle, earthworm, and invertebrate communities directly affects shrew survival. Cat predation kills millions of shrews annually, although cats rarely eat them due to scent glands. Shrews found alive by cats typically die from toxic cat saliva causing shock. The extremely high metabolic rate means periods of even a few hours without food cause physiological stress.

What You Can Do

Reduce garden insecticide use to maintain the invertebrate communities shrews depend on
Keep cats indoors at night when shrew activity is highest in garden habitats
Support soil health programs that maintain earthworm communities in agricultural and garden soils
Contribute shrew records to mammal recording groups using live trap surveys
Engage with wildlife gardening programs that maintain diverse ground cover providing shrew habitat