Right then, got a pretty decent sized back garden, about 60ft long, last 30ft or so is grass (not lawn before anyone asks)..
A coupla years ago noticed a wee hole near a tree- about 2 inches across..
Just did the first cut of the year and realised there’s now about 4 or 5 holes at different points around the garden and a few depressions near the holes also.
Holes can be seen below, shoe for scale!

We live on the edge of the city, a couple of streets away it’s all open countryside, fields etc..
Anyone got any idea what might have been digging? I’m not a big one for killing wildlife but concerned that my wee boy might trip on one of them and turn his ankle. Think I should put something nasty down to put them to sleep?

Rats.

Seriously? Cos if that’s the case will be buying poison and their ass will literally be grass.

Lots of advice on the net, this is from http://www.discoverwildlife.com/british-wildlife/how-identify-animal-holes

MOUSE HOLE
Bank voles, woodmice and yellow-necked mice can dig extensive burrow systems, often under tree roots.
Woodmice dig burrows in cereal fields and similar open situations.
The tunnels are generally only a few centimetres below ground, with entrance holes about 3cm in diameter.
Mouse holes are often camouflaged or blocked with debris, such as small stones, clods of earth or twigs. Tunnels – particularly those of the bank vole – frequently connect to runways above ground through dense vegetation.

RAT HOLE
Rats dig holes similar to those of water voles, 6-9cm in diameter. They are usually close to water, but are also found in a variety of other habitats such as hedgerows, rubbish tips and often under cover such as tree roots and logs.
Unlike water vole holes, rat holes generally have a fan-shaped mass of freshly dug soil outside and the holes are connected by well-trodden runways.

WATER VOLE BURROW
Water voles generally dig burrows in banks, with a series of holes close to the water’s edge or even under water.
Occasionally, holes can be 2–3m from the water.
Holes are roughly circular, 5cm–7cm in diameter, and generally have a closely cropped ‘lawn’ within a 15cm radius of the hole.

So yep, probably rats.

Stakeout!

Air rifle and nvgs! (is that allowed btw?..)
Seriously. Will put rat poison down the holes, block them up with quickset cement then fill the remaining top few inches with soil and seed it.
Guessing I’ll need to keep an eye out for new holes and take the same action as they appear.