All Thanks to the Gulf Stream
Thanks to the Gulf Stream, we enjoy a relatively mild autumn and winter and as a consequence, huge numbers of geese and ducks migrate to Britain from northern latitudes to escape hostile winter conditions. Why not get out and experience the sounds and sights of winter wildfowl for yourself?
For example, large flocks of brent geese can be found in Christchurch Harbour, Poole Harbour and on The Fleet. In summer they breed on the Taimyr Peninsula in arctic Russia but now they are feeding on eel grass, seaweeds and grass in eastern and southern England.
Estuaries, harbours and lakes are favoured by surface-feeding ducks including teal, wigeon and pintail which arrive from Iceland, Scandinavia and Russia. Listen for the evocative whistled 'whee-yoo' of the wigeon, which sounds rather like a firework!
What About the Butterflies?
Butterflies have been conspicuous in October due to the mild and sunny conditions, but what happens to them as winter approaches? The comma, small tortoiseshell, peacock and brimstone butterflies all hibernate, and recently the red admiral has been doing the same in southern England.
In contrast, the spring invasion of painted lady butterflies from Morocco produced two summer generations in England and although some were still around in late October they won't survive the winter. There is now evidence that some butterflies undertake a return migration, but fly south at high altitude and are largely unseen.
Then there are the majority of resident butterflies which don't survive the winter as adults but overwinter as eggs, larvae or pupae. In Dorset, the speckled wood manages three overlapping generations and adults can normally be seen each month from March to October. This year a few may survive into November.
Ivy Flowers a Rich Source of Autumn Food
Ivy flowers between September and November and provides a very important autumn source of pollen and nectar for many insects including butterflies, bees and flies.
If mild days persist this month, notice how insects gather at this food source. A dragonfly, the common darter, can also survive into November and beyond if conditions allow insect prey to persist.
Nature's Recycling Depot
Deciduous trees are now loosing their leaves in increasing numbers and although many leaves are accumulating on the woodland floor, the recycling process is already underway.Earthworms are pulling the leaves underground, fungal threads are penetrating the leaf structure and these and other soil organisms are feeding on the organic matter before returning the minerals to the soil.
Seen Any Mole Hills?
Moles are most abundant within the soil of deciduous woodland and permanent pasture and remain active throughout the year. Their winter diet consists almost entirely of earthworms which are collected from semi-permanent tunnels before being stored in large numbers in or near the nest chamber. In summer their diet expands to include insects and other invertebrates.
Don't Forget the Hedgehogs!
Finally, remember another insectivore, the hedgehog, which must find food in autumn to gain weight before hibernating through the winter. Hedgehogs occur in hedgerows, meadows and woodland edges, but also in suburban gardens, where they consume invertebrates, including slugs. Don't forget to check for hedgehog hibernation nests in piles of garden vegetation destined for burning over the winter.
Written by John Wright
Dorset Wildlife Trust Member & Volunteer