After the young have been born, a mother and her fawns will probably stay together for at least 10 months. This is a significant period of time, considering their relatively short life expectancy

Since the moment of conception, the youngsters’ father plays no part in the raising of his young. Although he may form a loose association with the mother and her fawns during the winter months – he will play no paternal role.

What causes the family break-up?

Once the fawns’ first spring arrives, assuming they’re in good physical condition, they will be fully able to look after themselves, and the family unit will soon start to fragment as the temperament of the deer changes.

But how, and when, the family breaks up depends on the sex of the youngsters.

Bucks leave first

Hormones flowing through the deers’ body causes their character to change, and the bucks are the first to be affected.

With the increased number of daylight hours, the males’ testes release more testosterone into the bloodstream and this causes them to become more aggressive in their behaviour.

Since the previous summer, the bucks have had an urge to dominate and they tend to be more vigorous in their play than their twin sister (if they have one). As their first year starts to draw to a close, the young males’ propensity to engage in physical contact increases; attempting to climb on top of their mother and tussling with a sibling, too.

They will also start to wander further and further away from their parent, eventually losing the strong bond their mother altogether. Once that happens, their independent life will have started*, although they can form a less strongly bonded association with their mother later in the year (see the notes included at the end of this post).

*If the buck has a brother, the two of them will sometimes move around the range as pair, but they, too, will be go their separate ways as summer nears.

Doe fawns linger longer

Female youngsters stay with their mother for a longer period of time than their brothers. There’s no surge of hormones making them aggressive, or compelling them to leave their mother.

Instead, the bond between a mother and her daughter (or daughters) can remain strong right up to the day of the birth of the parent’s new young. However, this is not the usual course of events. What normally happens is this:

About a month before the parental doe is due to give birth, the adult will become hostile towards her daughter and will forcefully chase her away, when she intrudes into her recently enlarged body space.

Signs that the bond between the mother and daughter has waned include the absence of mutual licking and no more gentle nose-to-nose contact between them.

Rather, these will be replaced by stern looks from the mother towards the young doe; eyes widened and head lowered, along with pulling her ears back, front foot stamping and short charges, sometimes forcefully urging her daughter to move off.

If a doe fawn has a twin brother (who would have broken the bond with the family earlier in the season), they can sometimes a reform as sibling pair, if he is still in the locality. But these too are likely to split up again, when spring becomes summer.

However, families can occasionally reform

For the many roe deer families, once they’ve split-up, the break will be permanent; they will lead completely separate lives and the yearlings will propagate the family bloodline in territories near and far.

Having said that, though, I have known two instances where the previous year’s youngsters have formed an extended family group with their mother and her new youngsters in the following winter. Both of these lasted into the next spring, but soon after the vernal equinox, the groups dispersed, and never reconvened again the following winter.