By Temple09
Avon,
United Kingdom 
Hi,
My question regards holes in the garden. As to the culprits, I have a number of possible candidates, but I am unsure whom to blame, nor what to do in order to prevent further holes appearing.
I live in Bristol. My soil is mostly very hard clay. However, due to me (gradually) trying to improve soil quality, as well as planting new flowers, the borders are somewhat mixed in hardness, depending on whether new compost/plants have been added recently.
The holes in question are not burrows, but are instead what you may expect from an animal burrowing to search for food. They are normally 2-3 inches deep, teardrop shaped and have a total diameter of 6-8 inches.
They have been made in the softer soil areas (particularly annoying, since this is where new, delicate plants have been planted), and one or two have also appeared in my large containers.
I know that there are rats and mice in the near area. Foxes too (although they seem quite small for a fox). There are plenty of cats (although there are not normally droppings nearby), a local hedgehog and of course lots of birds.
Can anyone help to identify my diggers, since they are really causing a nuisance, exposing roots and digging up newly planted flowers? Furthermore, how can I stop them without turning my borders into Fort Knox?
6 Jun, 2012
Answers
Might it be blackbirds? In my garden they sometimes disturb quite a lot of soil getting at food.
7 Jun, 2012
We have similar 'holes' in our garden, and we think it's squirrels as they're regular visitors. They dig in the area of the garden that's mulched with bark, so it doesn't create havoc with any new planting. If you can't or don't want to spread bark (or an alternative mulch) everywhere, perhaps you could pop some just around the new plants?
7 Jun, 2012
My guess would also be squirrels, rabbits or birds. Squirrels' natural food (ie nuts) being unavailable at this time of year, they dig around searching for their caches buried in autum/winter. Rabbits, too, will dig smallish holes at random, although I don't know why (nor, I suspect, do they!) Another very likely candidate is the blackbird, which is a determined and messy digger. Can you tell whether the displaced soil is in a vague heap beside the hole, suggesting it's been flung backwards between the digger's hind legs? Or is it tossed around all over the place? If the latter, a blackbird is probably the best bet. Another clue may be when the holes appear - during daylight or at night. Establishing this should narrow your search. Good luck!
7 Jun, 2012
Thank you very much for your answers, especially the detailed one from Carrotless.
In anwer to the latter, it sounds from your description that it may be blackbirds since the soil has been messily removed and flung about and tends to done at night (or at least ... before I get out into the garden, which could be any time in the morning).
Thank you once again Ma :-)
7 Jun, 2012
If its blackbirds you can forget the chilli!
7 Jun, 2012
Update!!!!
I have just found a new hole which may shed some light ... or may be a red herring.
There is now a hole in the lawn, about four inches deep and with a diameter of about eight inches. However, inside this one is the shell of an egg (standard chicken's egg, presumably taken from a bin by the animal in question).
I am guessing that that is less likely to be a blackbird.
Now I'm thinking mammal. But what? Badger? Fox? Rat?
12 Jun, 2012
A difficult one. Cats normally fill in their holes and foxes aren't usually so tidy. The best thing I can suggest is to spread some chili pepper or chilli flakes around on the softer soil. I found this deterred badgers anyway. You can get it in big bags from Asian shops - much cheaper than the small supermarket jars.
6 Jun, 2012