Everywhere I go, there seem to be parties of deer in the fields, something one never used to see. Have deer changed their habits or is it simply that there are many more of them?
There is more than one answer to your query. One reason is that the widespread removal of hedges provides wider views over the landscape and deer are easier to spot. Studies of so-called field roe abroad show that they are more likely to form sizeable winter groups in fields of more than 25 hectares, perhaps realising that distance from cover provides safety. Population density also has an important influence. Where deer are seen in numbers in the open, over-browsing in neighbouring woodland is likely to have occurred.
Digestion in roe demands high-value food provided by leaves, twigs and buds in the hedgerows, which are their natural habitat. A shortage of browse drives them into fields where they select the seed-leaves of weed and crop seedlings or subsist on crop residues and less nutritious grazing.