What lovely sunsets we have in the winter with our big Norfolk skies. Sometimes, while driving, I just have to pull over so as not to miss the wonderful colours; like everything in the natural world it’s a free show and there aren’t many things you can say that about!
On a bright day we’re often tempted to start tidying up in the garden but it’s best to resist doing too much for the time being. Leaf litter and other debris will be sheltering over-wintering insects; these are what Blackbirds are looking for when you see them rooting about and throwing leaves aside. The Ladybird is one insect that often decides to hibernate in our homes, sometimes in great numbers. They are thought to be able to find a hibernation site by following a scent trail left by others. Houses are not good places for ladybirds to spend the winter, though, because our central heating will cause them to wake up, thinking it’s spring time. There will not be any food for them and they will starve, so if you find them, clustered in a corner or tucked round a window frame, it is best to move them into a cool, dry place; porches, outbuildings or sheds are ideal. This does require a little patience but a paint brush used to gently brush them into a container will ensure that they are not damaged. (Go on, you can do it!) They will repay you by eating all your aphids when they become active in the spring.
January is a good time to clean out your nest boxes before the birds start to think about pairing up, although many are already showing signs; the colours of some male birds are brightening and they are beginning to display territorial behaviour.
As well as coming to our feeders, birds also rely on berries for food in the winter. Holly trees, garden shrubs, and wild roses all provide these – I watched a Blackbird take every single rose hip from one plant in a single sitting! There is a lot of ivy in our county and, though it can be a nuisance when it pulls down fences and walls and takes over trees, it does bear a lot of berries and these will be eaten by a variety of birds, so try to leave some where it will do no harm. Also the thick, evergreen foliage is ideal cover for roosting and nesting and the flowers in the autumn provide pollen for insects when many other plants have gone to seed.
A bird that had a much better year in 2014 than the previous year is the Barn owl, sometimes called the ‘screech’ owl because of the eerie shriek it makes. Bad weather in the early spring of 2013 meant that food supply was limited. Although we tend to think of owls as being nocturnal, Barn owls often hunt by day and winter is a good time to see them. They will eat insects, amphibians, birds, young rats and rabbits but they mainly feed on small mammals; voles, mice, and shrews are all taken but voles make up the greater part of their diet; wings fringed with soft feathers ensures that their flight is silent and the prey animal does not hear them coming. The hooked beaks of raptors are very sharp but they are used to tear off morsels of food when feeding, not to kill the prey. This is done with the needle-like talons which penetrate deeply and quickly dispatch the unfortunate animal; I have personal experience of how this feels. Late one night, when feeding an injured owl that was one of our patients, I forgot to wrap up his feet. He made a lightening strike and held on to my hand for nearly twenty minutes, tightening his grip every time I tried to pull away. I stopped moving and after a while he decided that my hand was ‘dead’ and relaxed his grip. I still have the scars!
As well as good vision Barn owls have a very acute sense of hearing and that round face, the facial disc, acts as a kind of radar dish, guiding sound to the ears. These are asymmetrical, the left being slightly higher than the right, and this tells the owl exactly where the rustling of the prey is coming from; hunting is not as easy in snowy weather and some starve in the winter. As with all owls, any indigestible material, bones, fur, feathers etc., is regurgitated in the form of pellets and they will be scattered at roosting and feeding places. A fascinating fact about these is that they themselves are little ecosystems. They provide food and shelter for other organisms including fungi, bacteria and a type of clothes moth which lays its eggs on the pellets. When the larvae hatch they feed on the fur and feathers, as do carpet beetles. Before humans invented clothes and carpets these insects inhabited bird and animal nests and the fur and feathers would have been their natural food. They probably didn’t have those names until we saw the results of their feeding in our wardrobes and on our floors! These pellets are a good example of how everything is linked; if one animal becomes extinct, it has a knock on effect on many other things. As John Donne said ‘No man is an island’ and this goes for birds as well. Anyway, you don’t want me coming over all unnecessary, so on with the owl!
2014 was a good vole year – they seem to come in cycles – so Barn owls had a much better breeding season than they did the year before, some rearing two clutches. The usual clutch size is 4 – 7 eggs but can be larger if food is plentiful. Nesting sites are in hollow trees or undisturbed buildings but, although many old barns have been removed or converted, we can help here by providing nest boxes; these can be obtained from the RSPB or the Hawk & Owl Trust and other organisations. Barn owls do not actually build nests, they lay their eggs on broken pellets and debris from the previous year. Incubation is by the female only and she relies on her mate to bring her food; they mate for life but if one should die the other will form a new partnership.
As was the case with all birds of prey, population numbers decreased when pesticides, such as DDT, were commonly used. These got into the food chain and affected the thickness of the egg shells, consequently many were broken before they could hatch. These types of chemicals are no longer used but deaths do result from others and changes in farming, habitat destruction and the Barn owl’s habit of hunting along roadside verges, which means that they are often killed by vehicles, have all contributed to its decline. Let’s hope that 2015 will be another good year for this beautiful bird.
Squirrel update: So far, Squirrel 7, Humans 0 – and he now has an assistant!
Thank you for your photos and questions; I hope my answers were helpful. Please keep sending them – I love the detective work!
Happy new year to everybody.
Activities this month include:-
- Talks and workshops by The Norfolk & Norwich Naturalists Society – www.nnns.org.uk
- Winter walks at Potter Higham – Hickling Broad.
- Hoe bird walk – Hoe Common.
- Woodland mystery tour – meeting point Acle library.
- Winter tide spring clean – Holme Dunes.
If the weather is bad, there are many indoor talks and meetings.
Details www.norfolkwildlifetrust.org.uk or 01603 625540.
© Sheila Sims 2015. Email: firstname.lastname@example.org