Biodiversity Northern Ireland

What to see and do in your garden in December

If you practise gardening with wildlife in mind, the winter months can really start to show how far your efforts are succeeding, at least as far as birds are concerned. They can also provide pointers as to what else you may be able to do.

Birds

Food is becoming far scarcer and more birds than ever will begin to move into your garden, in search of easier pickings. Many of these visits will be very fleeting but if there is a good supply of food around, some birds will return frequently or even stay for several days.  Resident populations of common species like starling, robin, chaffinch wood pigeon and members of the thrush family are swelled by large immigrant flocks from northern and eastern Europe and your local blackbirds may find themselves hugely outnumbered by these visitors.

Immigrant blackbirds tend to be shyer than those that may spend the whole year in and around gardens but the biggest clue to their origin is their sheer numbers. When the weather gets frosty, it may be time to retrieve those apples that you (may have!) stored in the freezer in the autumn when they were so plentiful. De-frost them and put them out on the grass early in the morning. Blackbirds love them, as do redwings and fieldfares, although the last two may only come to gardens in really hard weather.

If your garden provides plenty of shelter and leaf litter, wrens, robins and dunnock will be in evidence, feeding at ground level or flitting around among the shrubs, where the occasional goldcrest or over-wintering chiffchaff may also put in an appearance. On any grassy areas, look out for the odd pied wagtail or two. These birds commonly roost in urban areas, gathering each evening in substantial numbers but afterwards disperse during the day to feed. 

Naturally-supplied garden seeds and fruits are vital for garden birds in winter, as is the supply (albeit a diminishing one, as the weather gets progressively colder) of invertebrates that a well-stocked garden can provide. However, there’s no denying that the main centre of  bird activity  in most winter gardens will be the feeding stations – whether bird table, hanging feeders or simply scraps on the ground. Here, most gardeners will reliably expect to see blue tits, great tits, chaffinches greenfinches and house sparrows at the least, with coal tits very likely additions in some areas. Goldfinch numbers coming to garden have soared in recent years, as have those of long-tailed tits.  In gardens near woodland, redpolls and siskins are not unusual.

Mammals

Quite a few small mammals may use gardens in winter although unless you have a predatory cat you are unlikely to see them. The wood mouse Apodemus sylvaticus (sometimes also called the field mouse and notable for its very large dark eyes and long, oval ears) is active throughout the cold weather, sheltering underground when necessary, and may even continue to breed in mild winters.  Gardens with plentiful supplies of seeds and berries are likely to support a few wood mice. Wood mice take a wide range of foodstuffs including earthworms, insects and other invertebrates but are principally vegetarian. They have a fondness for bulbs and strawberries, which may not endear them to the typical gardener, but they are undeniably appealing creatures.

If your cat does catch a pygmy shrew, the smallest British mammal – it is unlikely to eat it as many predators seem to find shrews distasteful.  These tiny animals (adults are less than 60 mm long, of which about two thirds is the tail) are fearsome predators. During each period of 24 hours, they alternate between sleeping and feeding since they cannot go for more than a short time without sustenance. They will take anything small enough for them to tackle including spiders, worms, beetles and other insects.

Butterflies and moths

The only adult butterflies liable to be encountered in the winter moths will be hibernating, often in greenhouses or sheds but sometimes indoors, for example in unheated rooms. Among the species that pass the winter in this way are small tortoiseshell, peacock and red admiral. Of these, small tortoiseshells are the most likely to be found in houses. Peacocks may use sheds but seem to prefer holes in trees or dark, sheltered crevices in walls. Remarkably, large assemblages of peacock butterflies may produce a hissing sound if disturbed, presumably a warning to potential predators. Red admirals typically overwinter in exposed places where almost all die.  (Although this practice may not sound like a good strategy for survival, it seems to operate successfully in colder parts of Europe, so other factors – perhaps parasites – must be at work here, where it fails). If you do encounter a hibernating butterfly in the house,, it’s best to leave it alone. If you must move it, put it somewhere sheltered where the temperature is likely to be constantly cool until the spring. If a butterfly that has been hibernating in your house becomes active, place it in a container (one through which air can circulate) and store it in a cool place - the butterfly should soon become dormant again until warmer weather arrives.

Of the 1000 or so species of moth found in Northern Ireland, a very small number are naturally active as adults throughout the winter. One of these is the very appropriately named winter moth Operophtera brumata.  This can be found almost wherever there are trees and so is not uncommon in urban gardens. The flight period lasts from November to January. The December moth Poecilocampa populi (which, despite the name, flies from October to January) is also found in gardens although less commonly. An excellent source of information about moths and butterflies in Northern Ireland is http://www.habitas.org.uk/moths/frameset.html This only covers about half the species found but is steadily being extended.

Things to do

Many of the tasks suitable for late autumn months may also be undertaken in December, if the weather isn’t too harsh. These include:

• Starting a compost heap or leaf cage
• Building a pond
• Making a log pile or stone and earth bank
• Planting a tree or hedge
• Making a bird table, bird box or bat box
• Setting up a bird bath

Make a plan!

If the weather is vile and you just can’t face going out into the cold and wet, you can still start to provide for the wildlife in your garden in future by thinking what to do next year! Leaf through books and catalogues or browse the internet for ideas. Whatever the size of your garden, and however much you may already have done to make it attractive to wildlife, there is always more to learn and there are always improvements to be considered.  Two good sources of ideas on the web are the RSPB’s Homes for Wildlife - http://www.rspb.org.uk/hfw/ and the more recent Big Wildlife Garden http://www.bwg.naturalengland.org.uk/. The last of these is aimed primarily at an English audience but all the advice on the site applies with equal force throughout the UK.