What’s nibbled my new Apple trees

We have planted 4 new Apple trees, stems are maybe 25 to 35mm. About 1.5m high

Some tiny nibble marks have appeared, mostly near the top. They are maybe 5mm or so wide, so go round the tree maybe 10mm. They look a bit like a tiny Beaver has climbed up and nibbled

I am not convinced it’s deer as the tree is still intact, there’s no attempt to bite the stem off and the marks look more rodent like. No evidence of rabbit or in fact anything that size, plus too high for a rabbit anyway

Would do pics but, you know

Any ideas? I’m wondering about mice or something similar

Squirrel, or baby Robin

If you’ve had the weather we have, likely otter as it swam past.

Our squirrels have never damaged apple or plum tree bark. They have eaten new buds, dug up the lawn and dug into plant pots though

Alliums and strong-smelling plants will keep some rodents away and are far nicer to look at than tree guards

Genuine chuckle @ midlifecrashes 😂

Deer tend to browse off the tops of saplings up to 1.2m in height, or fray the bark of mature trees by thrashing (Roe bucks do this as a rutting/territorial thing and it’s the wrong time of year for that) . They may even strip the bark but they don’t have the sort of teeth to nibble.  So I reckon you can discount deer.

Rabbits and squirrels are your next best bet, but don’t discount voles:

https://www.forestresearch.gov.uk/research/recognising-types-of-mammal-damage-to-trees-and-woodland/#tablea.

Baby giraffe. 😉

If there’s grey squirrels around, you need pine martens.

Squirrels will strip the bark off trees, although it’s usually bigger trees. Hard to know without seeing a photo. Try googling ‘tree squirrel damage’ and see if it looks similar.