Meet one of the reserves most elusive mammals, the Water Shrew, in this new blog by local naturalist Christopher Wren.
Gosforth Nature Reserve is home to all three of the UK’s native shrew species. The largest and least common of these is the Water Shrew (Neomys fodiens). Like all shrews it is elusive, carnivorous, hyperactive and short-lived.
Water Shrews live close to the water’s edge and hunt along the banks or underwater. They are expert swimmers, aided by their hairy feet which act as if they are webbed.
Water Shrews eat aquatic crustaceans, insect larvae, water snails, small frogs and small fish. They subdue their prey with a venomous bite and cache excess food in larders. They are constantly active, day and night. At night the camera records with infra-red light to produce a black and white image, as in this video.
In daylight the video is in colour although apart from its pink nose the shrew is still black and white.
In the next video the shrew eats first a freshwater shrimp and then a caddis fly larva. It is so quick that I have added a zoomed-in slow-motion replay to show what is happening.
The problem with having a food store is that something else might find it. Here the shrew stocks the larder and later comes out of the nest for a snack. But when its back is turned a wood mouse raids the larder, running off with the food twice and staying to eat it the third time.
Water Shrews live in the reserve all year round but are rarely seen. Perhaps the best chance of getting a glimpse of one is near the dipping pond.