Beech and climate change. Beech trees are important (ecologically and financially) in the woodlands and forests across Europe.  Beech has a wide distribution from Southern Europe up into Scandinavia.  However, the beech has a relatively shallow root system and this makes it susceptible to drought.  In recent times, as a result of climate change, extreme weather events such as drought have become more common.  Analysis of beech tree rings (from 5000+ trees) across Europe suggest that whilst those Sweden and Norway are growing quite well those in Southern Europe are not, in fact growth may have declined by as much as 20%.   Current climate projections suggest that beech growth / productivity in southern areas may decline further, with increasing mortality. Warning signals. Many animals are able to send signals to other members of their species warning them of imminent danger, such signals can be warning sounds or ‘scents’.  The scents may be in the form of pheromones, essentially ‘airborne hormones’. Now there is growing evidence that plants may be able to act in a similar way.  For example, if mint leaves are damaged by a insect herbivore attack, then field mustard and soybean plants growing in the vicinity respond to the volatile chemicals released by the mint and activate their leaf defence systems (this often involves creating an unpalatable taste).  The volatile compounds released (during damage) are ‘oils’ or terpenes, like  β-Ocimene.  β-Ocimene has a sweet, woody fragrance but it is not clear how it stimulates other plants into activating the genes for their defence mechanisms.   Research is underway at the Tokyo University of Science. Lead and Birds of Prey.  Birds and Prey feed upon flesh they scavenge (like the entrails of deer, or dead pheasants) or from animals they capture.  The trouble is that often this flesh is riddled with bits of lead shot.  Lead is a poison, and is not easily eliminated from the body.  Animals injured by lead shot may suffer a slow and agonising death. Those that feed upon them also accumulate lead in their bodies, which affects their physiology and behaviour. Now Cambridge based scientists have studied the lead levels in a variety of birds of prey.  They looked at lead levels in the livers of some 3000 raptors. Birds, like eagles, are worst affected as they are long lived, breed later in life and rear relatively few young per year.  For a number of species, they have been able to estimate the % reduction in population size that the lead is responsible for. Species Estimated % loss of population White tailed eagle 14 Golden Eagle  13 Griffon Vulture 12 Red Kite & Western Marsh Harrier 3 Buzzard populations are estimated to be 1.5% smaller, which may not seem much but it equates to the loss of some 22,000 birds. Lead is still used in shotgun cartridges, many pheasants are still  killed with lead based ammunition, despite requests to hunting groups to switch to non-toxic gunshot (by 2020).  Full details of this work can be found here. Warmer autumns and butterflies. Green veined white butterflies are common in the U.K. and Europe.  Researchers in Sweden have been looking at how they might respond to warmer and longer autumn weather.  Under laboratory conditions, they exposed the chrysalises (over-wintering stages) of the butterfly to warmer autumnal conditions.  They found that the chrysalises used more energy and lost more weight under these conditions, and were less likely to survive to the adult / imago stage in the following Spring.  With global warming affecting our climate, it could be that populations of this butterfly could struggle as time passes.

For millions of years, forests and woodlands have been changing - as a result of natural regeneration, storms, fires and climate change.  However, with the expansion of human populations, woodlands and forests have been cut down to make way for towns, cities and the infra-structure of ‘modern’ life.  Sadly forests, and woodlands such as those in the path of HS2,  are still disappearing. ‘Untouched’ rain / tropical forest is being cut down to make way for cash crops; plus vast wooded areas have been destroyed by fire in Australia, Sweden and on the West Coast of the United States in recent years. Clearfell of any forested area for timber or agriculture involves the removal of all trees / vegetation and is sometimes followed by burning of the remaining debris. Clearfell can also have unintended consequences (beyond the loss of entire animal communities.  An Australian study has shown that it lowers soil nutrient levels - notably nitrate and phosphate.  Furthermore, the use of heavy machinery in clearfelling can compact the soil and its consequent exposure to the elements can lead to erosion (rain runoff).   When an area is subject to intense fire, there is a drop in the organic carbon content of the soil and structural damage to the soil; it can take many years for such fire-damaged soil to ‘recover’. Forests and woodlands support the vast majority of land-based species. However,  the species that we see today on a woodland walk may be different to those our ancestors might have seen five hundred or a thousand years ago.  Certain species only survive in relatively undisturbed (and ancient) forests / woodlands.  There are species that can ‘deal’ with disturbance and are adaptable, indeed opportunitistic,  such as red deer and fox.  The same can be said for certain plants species, which can become invasive.   Changes in species make-up and biodiversity do not always immediately follow loss of forest or woodland.  Generally speaking, the longer the life span of a species then the longer for the effects of forest loss to become apparent.  It may be that the effects ‘span’ generations, raptors / birds of prey may manage to raise their young in the immediate period following loss of forest or woodland. But their offspring may struggle to survive in a depleted environment. It might be that with limited resources an animal might simply not reproduce for years, if ever again.  Consequently, the impact of forest destruction / loss that species depletion might not be apparent for many years. The loss of forests and woodlands has lead to many local, national and inter-national initiatives to offset these losses: for example, New Zealand’s ‘One Billion Trees” project and the Nature Conservancy’s “plant a billion trees’ campaign.  Broadly speaking, reforestation involves the planting of native trees in an area, whereas planting with new (non-native) species is afforestation. Recent research suggests that whilst non-native plants often grow faster than native species, they also have less dense tissues (think: oak versus larch) and decompose more readily, which can contribute to more rapid cycling of carbon.  This will not help to mitigate climate change. It is also important to consider which trees might prosper and offer resilience in the light of climate change. Our climate is changing and will be different in the future, with summer temperatures being higher.  We have already seen more extreme weather events (leading to flooding and wild fires).  Forestry England has a number of tools to help plan which tree species will be suited to a site, now and in future.   There is ESC4 which offers a means to help forest managers and planners select tree species that are ecologically suited to particular sites; and there is also the climate matching tool.  As Forestry England says this is “so that we can see which places in the world currently experience the climate we are projected to have in future. We can compare these different places to help us plan which tree species will be suited to a site, now and in future”.  One strategy is to create woodlands that are more diverse, as it thought that diversity helps woods more resilient to climate change. This can be through encouraging a range of different, but carefully selected trees to grow, and being aware of the provenance of seeds or saplings.

Following seemingly weeks of awful weather and awful news the 16th March was an amazing spring day, clear blue skies and gentle warm sunshine - a good day to see what was new at the wood.  As it turned out there was plenty. We heard our first Chiffchaff of the year, and saw Great Tits beginning to explore nest boxes. When we arrived the pair of Buzzards were active, and we also noticed a male Wren busy building a nest in a large insect box we were given at Christmas, and fixed close to the ground by our coffee spot. They are confident birds, but difficult to photograph because of their cryptic colouring and speed, and their penchant for the dapple of undergrowth and nooks and crannies. However this bird was out and about, and back and forth to the box collecting moss from the base of near by trees.  Read more...

Today, we have a new woodlandsTV film about Red Kites. Whilst the red kite was not an uncommon sight in mediaeval times, come the twentieth century it was a rarity.  Indeed, the breeding population was restricted to a few pairs in parts of Wales.  The red kite is a bird of prey and belongs to the same ‘family’ as eagles, harriers and buzzards; all are raptors.  The kite was first described by Carl von Linne, who gave it the name Falco milvus. A French taxonomist later moved the species to the genus Milvus, so it became Milvus milvus (bit of a tautology that).   There are two other species in the Milvus genus : the black kite and the yellow billed kite.  The word kite may derive from an ‘old english’ word cyta.   The birds are approximately 2 feet long but have an extensive wing span of 5 feet plus.  Much of the body is covered with reddish brown feathers, which contrast with primary flight feathers that are white and the black wing tips. Read more...

Well, not ours exactly …. but during the spring and summer it’s rare for us not to see and hear the buzzards. In Woodcock Wood they fly above our backdrop of Corsican pine and make forays across the chestnut coppice, occasionally perching in the tall oaks. With open fields behind the pines, this makes the perfect habitat for this beautiful bird. We are lucky that Woodcock Wood is a small but central part of their territory. We see them most often in spring when the pair renew their vows in noisy and beautifully aerobatic courtship displays. It’s usually their calls that attract our attention, and then it is a privilege to watch their mastery of flight in these displays. Read more...