What is the collective noun for a group of moles (animal)?

Male moles are called "boars", females are called "sows". A group of moles is called a "labour" or "labor", although they are rarely seen in groups as they are very solitary animals, generally coming together only for their mating season.

Moles have cylindrical bodies, velvety fur, very small, inconspicuous ears and eyes, reduced hindlimbs; and short, powerful forelimbs with large paws adapted for digging their tunnels or ‘runs’. The mole runs vary in depth from surface runs only a few inches deep, to main runs, some 12 to 18 inches deep.

The disturbance of the soil brings an important benefit by aerating and tilling it, adding to its fertility. Molehills are therefore sometimes used as a source of good soil for use in gardening and are particularly valued by some practitioners of permaculture for fine potting soil.

However, tunnelling moles may cause damage to gardens and functional areas of grass such as pasture land, and they represent a minor safety hazard. In 1702 King William III of England, Ireland and Scotland died of pneumonia, a complication from a broken collarbone following a fall from his horse. The horse had been confiscated from Sir John Fenwick, one of the Jacobites who had conspired against William. Because his horse had stumbled into a mole's burrow, many Jacobites toasted "the little gentleman in the black velvet waistcoat".