Posted: Tuesday 11th February 2014 by BrianEversham
Clear glass-snail, Aegopinella pura by Brian Eversham
Wildlife is experiencing a very mild, wet winter - good for species which remain active throughout
Behind the headlines about floods and storms, the lack of frost and ice has passed with little comment. Wildlife is experiencing a very mild, wet winter, which is good for species which remain active throughout. It’s the season of greatest growth for mosses, liverworts and lichens, and it’s when many slugs, snails, millipedes and woodlice are active and breeding. Turn over logs in any of our woodlands, and you will find a range of invertebrates active in the leaf-litter at the soil surface, whereas in harsher winters they would be well buried.
Irish yellow slug Limacus (=Limax) maculatus, Common Pill-woodlouse, Armadillidium vulgare and Lunaria cruciata, crescent-cup liverwort
I spent an enjoyable couple of hours at Overhall Grove last weekend, and found glass-snails, main picture, and hive-snails active, a land flatworm crawling under a dead log, and even a nest of red ants active on the soil surface under a small log surface - I’d never realised that very young ant grubs, Myrmica ruginodis nest with small larvae below, were so hairy!
But the mild weather may be challenging for species which hibernate, as they will use more energy at the higher temperatures, and probably be more vulnerable to fungal and bacterial diseases. Some are also prone to being disturbed into activity - I’ve seen small tortoiseshell and peacock butterflies, and queen bumblebees on the wing already, too early even for willow catkins, and foraging for non-existent nectar. And ‘spring’ flowers are at risk of frost damage if they grow too early: lords-and-ladies is already unfurling its leaves, and some annuals such as hairy bittercress are flowering already. Mis-timing of life cycles is one of the predicted consequences of climate change, especially in a country where weather is particularly variable and unpredictable.
We don't often examine our nature reserves in terms of microclimate, but this may be one of their underlying virtues. A large woodland has more 'middle' and less 'edge' than a small wood, and the cool dark conditions in the heart of Gamlingay Wood , High Wood or Old Sulehay Forest are the best places for many of our most specialised woodland plants and animals. The parts which border arable farmland will have greater extremes of temperature, may dry out more in summer, and are also likely to suffer from fertiliser and pesticide drift - you may have noticed the concentrations of nettles and good-grass in the outer 50-100m of many woods - these are plants which enjoy high nutrient conditions, but are out-competed in the middle of the woods.
One of the many benefits of Living Landscapes will be the buffering of sensitive habitats from the impacts of surrounding land use, be they chemical or climatic.