Species of the Month - January 2016: Yellow meadow ants & their hills

Yellow meadow ant hill on Common HillYellow meadow ant hill on Common Hill

Yellow meadow ants (Lasius flavus) live together in colonies which can be made up of over 5000 individuals. Together they dig through the soil to create intricate underground networks and spaces and deposit the excavated soil on the surface. This builds to form an ant hill which can get up to a metre tall, though most you see are around 30 – 40 centimetres.

The active movement of these ants can make the ant hills feel warm to the touch in summer months. Worker ants inside the mound busily move eggs, larvae and pupae to ensure they're on the sunny side of the mound. This attracts basking butterflies, reptiles and the common field grasshopper which lays its eggs on these hills. The warm, dry crumbly soil on top of the ant hills is also a great place to find small but interesting plants like early forget-me-not, lady's bedstraw and wild thyme.

Yellow meadow ant queens have been known to survive for more than 20 years and, what's more, it appears that queens that die are replaced, thus ensuring the continuation of the colony. Clearly, if left alone, some of these ant hills could survive longer than some human buildings!

Male Green WoodpeckerThe ants play another part in the food web too – as lunch. Ants can make up as much as eighty percent of the green woodpecker’s winter diet. It has an extraordinarily long tongue which it protrudes deep into the ant hill. No doubt a welcome meal on a cold day for many birds overwintering here.

Where to see them

Yellow Meadow Ant HillsWinter is a good time to see ant hills, as grass and vegetation has died back leaving the tussocky hummocks exposed. They are found in grassy areas (hence the name meadow ants!), but only those which haven't had tractors and machinery driven over them, as the ant hills are too fragile to survive being squashed. This means that they are now commonly associated with what are termed ‘species rich’ meadows where a lack of improvement (by application of fertilisers or pesticides) has allowed a wide variety of flora to flourish – in turn supporting a wide range of invertebrates, birds and mammals. So, if you’re out looking for ant hills, you might see lots of other wonderful things too!

Pied FlycatcherSome of our reserves are particularly good for seeing ant hills. Explore Common Hill or Wessington Pasture, which are both just west of Ledbury, near Fownhope. Further afield, you can also see them at the Christopher Cadbury reserve, Woodside or the meadow at Crow Wood reserve, near Vowchurch, where pied flycatchers have also been seen feeding from the ant hills.

Get in touch

If you do spot any ant hills please do let us know! You can submit records online here, email them to us at records@herefordshirewt.co.uk or write to us at Lower House Farm, Ledbury Road, Hereford, HR1 1UT.