First up is our most common owl, the tawny owl (Strix aluco). Autumn evenings are the best time to hear them because this is when established pairs are defending their territory ahead of the nesting season. But are you likely to hear them in the middle of a city?! 

One of the big questions is would they find enough to eat? Tawny owls feed on small mammals like mice and voles, but is there likely to be enough of these in Bristol? And what about mature trees? Tawny owls need these as a place to roost, build a nest and to use as a vantage point from which to hunt. Or perhaps tawnies have found ways to adapt to urban living like other kinds of city wildlife? 

We’re back with tawny owls in episode 3, this time in a location more commonly associated with them – the woods! We accompany Chris through a woodland managed by Somerset Wildlife Trust in search of 3 breeding pairs. He has been monitoring the tawny population here for decades and this evening he’s hoping to record their calls. However, wildlife doesn’t perform on demand, even if you’re recording for the BBC! Luckily, Chris can speak ‘tawny’ and what’s more – they answer back!

Using the skill he has honed since childhood he gets the attention of the resident owls by ‘posing’ as a young male owl just passing through the territory. The males respond with the classic wavering ‘OOOOOO!’. Females make their own version of this, as well the familiar ‘KERWICK! KERWICK!’ call, which they use to stay in touch with their mate. 

As Chris puts it, tawny owls are a good indicator of the natural ‘health and wealth’ of an environment, whether it’s an urban park or woodland in the countryside. If they have enough trees and a plentiful supply of small mammals to eat, then there is a myriad of habitats and resources available for other wildlife too.

The little owl (Athene noctua) is also on Chris’s list, which in episode 2 takes him back towards Bristol, to Ashton Court. This owl is not native to the UK but was introduced to southern England by Victorian gardeners in the 19^th Century. They were under the impression that it would hunt bullfinches eating the buds of fruit trees in spring. However, although it will occasionally take songbirds, the little owl’s natural prey is insects and small mammals. Therefore, its ideal habitat is rough grassland and mature hedgerows across park and farmland. 

As an introduced species, it is unusual in that it hasn’t had a negative impact on our native flora and fauna, but in recent years its numbers have been declining, and this is a concern because this may be as a direct result of the loss of its habitat. Again, Chris has come to record the local birds – but all is quiet.

In episode 4 we take a trip abroad to Sweden in search of the magnificent eagle owl (Bubo bubo)!

We return home again in episode 5 to a barn on the Somerset levels, where barn owl chicks are demanding to be fed! Chris sits quietly in a corner (with a cup of tea and cake!) to observe them and the tireless efforts of their parents. 

The barn owl (Tyto alba) usually breeds in late spring, but this is mid-September, so these chicks are very late. This may because the harshness of the previous winter killed off many of the tiny mammals that they depend on most for food: the short-tailed vole. Chris can guess the age of the chicks and explains to us how to tell the difference between male and female adults – the front plumage of male barn owls is pure white, whereas females have light or heavy black speckles. Also, the back plumage on females is a darker, richer brown towards their head.

Both chicks make a constant hissing sound that is impossible to ignore! This is their call to their parents to feed them, and it is so persistent that apparently the adults will sleep elsewhere during the day just to get some peace!

Owl Prowl on BBC Sounds