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Nature Notes from Hilltop News Nature Notes If you enjoy living or visiting the Chilterns you cannot fail to be impressed with the variety of landscape, wildlife and the particular weather it offers be it over the seasons of the year or just on a single day. What's more on any given day, the countryside in which the hilltop villages nestle is often characterised by having its own micro-climate compared to the neighbouring towns and countryside beneath it. This in turn has influenced the composition of local habitats and the occurrence of wildlife. No one set of eyes, ears and sense of smell can capture the essence of the natural history of the hilltop villages. The following nature notes first published in the Hilltop News are just a simple attempt to reflect on the flora and fauna we enjoy through the seasons. These articles were previously published in "Hilltop News".
Chris Brown
Nature Notes for Hilltop News December 2003 Measuring the fall in water level (as much as 10 inches per week) from the garden well in mid November confirms the obvious that the water table in this part of the Chilterns is now worryingly below normal levels. With only an inch (25mm) of rain in October, the prospects for our woodlands, farm crops and wildlife is a particular concern this winter and next year. The signs of this can be seen all around us. The Indian Summer has meant that trees remained in leaf much later than usual but also drew on even more ground-water than usual. Hence the spectacular display of reds and browns. However we can also expect to pay for this with a severe dieback over the months to come and regular loud thud of boughs falling from over-stressed trees, so take care on your winter walks. 
The winter season is an excellent time to look and listen out for, our local wildlife. For mammals and birds, there is a necessary trade off between conserving vital body heat and braving exposure to the cold air to participate in feeding frenzies during the reduced daytime hours. With shortening day lengths and night-time temperatures falling to below -3°C from the start of November, animals have been preparing for winter by building up their body fat, storing food away and insulating their nests. It is often and mistakenly thought that many of our mammals like 'cold-blooded' fauna (amphibians and reptiles) and many invertebrates also hibernate over the winter period. In fact whilst several become less active, only three of our resident mammal families actually hibernate; the hedgehog, the dormouse (including our notorious 'local' the Glis glis) and all sixteen of our native species of bat. So what are the reasons that distinguish these three very diverse mammals from all the others who may be less active but do not hibernate? Well the most likely reason is that their diet is primarily insects which are not available in winter. 
If parts of your lawn look like a pincushion this is the work of the green woodpecker with their characteristic shrieking call as they probe for invertebrates including the leatherjackets (cranefly larvae) I spoke of last time. Not all species of flora lie dormant at this time of year. Many mosses take the opportunity of the moist atmosphere which condenses on their leaf tips to put on a growth spurt and put up their spore capsules on long stalks which noisily discharge their spores from capsules ringed with shark-like teeth as the air dries at day break on frosty mornings. For the early riser the opportunity for a prize-winning photograph at next year's Hort Soc Summer Show. With bountiful quantities of beech 'mast' and hornbeam seeds in our woodlands look out for birds such as the brambling, a winter visitor from the continent particularly in hard winters. Meanwhile bullfinches will be chattering as they busy themselves finishing off the sloes and other berries and thrushes smashing snail shells on their favourite stone. Over-wintering starlings flocking as darkness falls can deafen the unsuspecting evening walker as they squabble over the most desirable roosting sites. Badgers will make only rare forays before mid February when their cubs are born but listen out for their tell-tale grunts and snuffles after dark. Both foxes and muntjac make their presence felt this time of year with their distinctive high-pitched cries which may account for a somewhat spooky story I unearthed about Cholesbury Camp a while back. Ever heard of the 'Screaming Pigs of Cholesbury'? Well the story is told of strange 'unearthly noises' emanating from Camp and the reluctance of even the most fearless of the men of the village to enter the Hillfort after dusk. So if anyone fancying a stroll as darkness falls is welcome to test out this theory let me know what happens! 
Many thanks for the comments since last month, as usual, please email me with any observations. chrisbrown@rayshill.com
Nature Notes for Hilltop News October / November 2003 Despite the record-breaking weather of August with temperatures here reaching a steamy 36.3°C, by the time you read this I suspect autumn might already have signalled its arrival by way of morning mists, a severe frost or chill winds. However, as a testament to the enduring summer we have just experienced, I am sitting in the garden writing this article in the second week of September shaded by umbrella from the heat of the afternoon sun. The lawn resembles the Arizona dustbowl. Small Copper butterflies still abound, chasing each other at high speed and exercising their almost exclusive rights to the still resplendent blooms. 
October signals the start of a month of rapid change for flora and fauna. On balmier days bees, of which the British Isles can boast over 250 species, over-wintering butterflies and other insects can be still seen on ivy, which flowers this month, stocking-up on the rich nectar, or sipping the juice oozing from overripe blackberries. Surprisingly, compared to most other years have you noticed the absence of wasps? The hot dry summer put paid to many garden pests and this shortage of flies and larvae in the latter part of summer will mean less food for the next generation of 'wapses'. As an aside, this is a traditional English word for wasps and is also the origin of a field name in this parish 'wapson' or 'wapoon'. To further support the 'wasp thesis' have you noticed the abundance of their fellow predators, the dragonflies, this year, which have been omnipresent as they patrol much further afield than normal from ponds, searching out their prey along our hedgerows and gardens? Ladybirds have suffered likewise. This absence of insect prey will also take its toll on birds that rely heavily on grubs for energy to keep warm on cold nights. The demise of slugs and worms will knock on to small mammals such as hedgehogs. A few judiciously placed hollow sticks in a dry place or a pile of logs will provide a refuge as well as a vital source of food for their predators. 
Despite the reliance on calendars and clocks these days we seem still to be able to sense subtle changes in the seasons. A lively conversation with a local couple about the colour of the leaves on the beech trees around Cholesbury Camp and whether or not the way the trees shed their leaves informed us about the weather, started me thinking about how, at this time of year, each tree displays its own characteristic way of changing colour and shedding leaves. I think those of us lucky enough to live alongside trees are familiar with this annual parade and seem able without realising it to identify small variations in the timing and sequence from year to year. How each species of tree reacts in its own particular way is primarily down to shortening day length but is also affected by water availability, temperature and light. For example, most hawthorn trees will already be bereft of most of their by now shrivelled leaves and the race will be on to see whether it is the fieldfares and redwing arriving from north-east Europe or the thrushes and bullfinches that strip them of their ripe 'haws'. The ash uniquely has a two-stage leaf-shedding approach triggered by the first hard frost of the season. Following such a cold snap it first looses just the leaves, leaving the stalks, which then fall a day or two later and temporarily giving the tree a frizzled look. Meanwhile the ash fruits or 'keys', at first green but later red-brown, are left dangling all through winter until spring. In contrast, horse chestnuts appear to have already anticipated the change and display a kaleidoscope of pastel hues. 
Finally for the most unusual sight this month, although I guess gardeners and naturalists might disagree; look out for the antics of the daddy-long-legs (cranefly) behaving like an arthritic acrobat as they lay their eggs deep underground in your lawn with their oversized ovipositor. However if it has not rained by then and the ground is still more like Arizona than Hawridge at least spare a thought for them! Many thanks for the comments since last month, as usual, please call (758890) or email me (chrisbrown@rayshill.com) with any observations.
Nature Notes for Hilltop August 2003 Looking back to June a steamy 28.9°C was clocked up on the 16th and July temperatures hit circa 30°C. June also managed to contribute 44mm of rain, including just shy of an inch (23mm) in a mere 7 hours on the night of 22nd. Only January has seen more precipitation and my farming guru Nigel tells me that this sporadic rainfall will mean some lower crop yields this year. Ironically, the seeds for this were sown (excuse the pun!) during last year's wet autumn. He tells me this encouraged 'shallow rooting of 2nd year wheat' which has then suffered during the very dry Spring. It is probably a certainty that debates over the pros and cons of GM crops, 'Set Aside', the EU CAP and the future direction of farming itself will ebb and flow for some time yet. Amidst all this though, the unpredictability which climate change brings also serves to increase the risk that making the wrong choices now, for the future of agriculture will similarly upset the delicate balance of nature overall. 
Butterflies provide one such barometer of this interrelationship. August is their high season and the second generation of Small Tortoiseshells, Commas and Red Admirals are hunting out their favourite food plants. So leave some nettles in a sunny location in your garden. Adult Peacock butterflies, like their cousins, hibernate and survive almost a year, emerging next May! 2003 has been a record year for the Painted Lady. The last was 1996. The first generation made their way here from southern France or even the North African coast, attracted by the scent of abundant nectar. They have a lazy flight, not surprising given the distance travelled! Sadly, the second-generation adults emerging in September do not usually survive our winter, but some are thought to successfully complete the return journey south in autumn. Makes commuting to London sound a doddle! 
Meanwhile the Speckled Wood - brown and yellow-spotted - enjoys woodland glades and shady paths. The males are fiercely territorial. They lie in wait for passing rivals to enter their area and take instantly to the air and engage in a dog-fight, each trying to outperform the other and impress the females with their tight spiralling manoeuvres, made possible because one wing is smaller than the other. You may find they follow you down the path until realising you're not a threat! Perhaps because most moths are drab and fly at night they get bad press, but there is a distinguished band of day-fliers, resplendent in their striking costumes, such as the Cinnabar - black with crimson - advertising that it is one of the most poisonous moths in Britain. The rare but spectacular Hummingbird Hawkmoth, is another French tourist, bee-like and fast flying. 
Of course one of the major reasons today why we have less butterflies, moths and other invertebrates has been the indiscriminate use of insecticides and herbicides enabling monocultures to dominate and squeeze out weaker, valuable species. In turn this means less birds, and insectivorous mammals, particularly noticeable after a hard winter. When these interrelationships get out of balance we all suffer. So why not encourage some individuality of style, some untidiness. Resist the urge to edit the countryside and introduce a metropolitan like symmetry to our village life. Put off cutting back that hedge for a second year encouraging more fruits to form. Allowing roadside hedgerows to grow taller also ensures that the barn owls patrol the verges slightly higher up as they hunt those small mammals thus avoiding collision with vehicles. We are blessed in the Chilterns in having an abundance of hedgerows and herb-rich verges. They encourage variety and serve to conserve that all-important balance. Thanks to those who e-mailed me with observations. As always I would welcome comments and also contributions from anyone for next month's article.
Nature Notes for Hilltop News June 2003 In my experience as a weather reporter (all of 6 months that is), it's rare to be able to say "this had been one of the hottest months since records began" but I've said it now! Although not exactly an all-time record, April was unusually warm and sunny with moderate SE winds throughout the month. Although clear skies produced a cluster of frosty nights until 14th, a reading of 26°C was clocked on 16th, close to the UK maximum on that day of 27.3°C in Wolverhampton. This was in fact the third highest April temperature on record for all-time and not surprisingly, this was also one of the driest Aprils on record. The rain gauge recorded 38mm (1.5") mostly falling all at the end of the month. June usually signals the start of the summer season but if planting out seedlings beware of the odd frost during the first few days. 
In the last edition of HTN I mentioned the cuckoo would be announcing its arrival in April. Reliable reports place the earliest call heard in this locality on April 14th which was way ahead of when the 'first heard' reports in nearly all other UK locations occurred. A number of plants and animals have cuckoo in their name and are connected with folklore. The pink-flowered cuckoo plant (ladies smock) is so-called by virtue of flowering around the time the first cuckoo is heard. Cuckoo bees and wasps lay their eggs in the nests of their hapless cousins that they mimic. However, the arum lily's other name the cuckoo pint plant has links back to the loose morals of the 17th century aristocracy, hence its alternate nickname of 'lords and ladies', enough said! 
The cuckoo-spit insect or froghopper is responsible for the spittle that appears on grasses and herbaceous plants around now and is said to have derived from the arrival of the spittle on plants coinciding with the first call of the cuckoo in spring. There is also oblique reference in folklore to superstitions about spitting to avoid bad luck whenever a cuckoo is heard. Certainly cuckoo-spit was an important ingredient in witches' brew (as in Macbeth) and in Scandinavian countries the froth is known as 'witches' spit'. 
The results of the national survey of garden birds have recently been published. In first place was the starling, followed by the house sparrow. Despite being the nation's most numerous garden birds by far, both have been in decline until recently. In 1979 the average per garden was starling-15 and house sparrow-10. In 2003, both are down to 5, although there is now a slight upward trend in numbers. The starling population is one that may be an early indicator of the impact on migratory birds of global warming. In May the RSPB carried out a further survey of house sparrows. The most at one time in our garden was a flock of 10. I'm interested to hear whether anyone else has seen any increase this year in line with national trends. To find out more go to www.rspb.org. In next month's article I plan to talk about some of the butterflies we can see in the area so in the meantime, whilst in the garden or out and about, make a mental note of the different varieties or, if you do not recognise them, just their colours and the particular behaviour that they exhibit. Thanks to those who e-mailed me with observations. As always I would welcome comments and also contributions from anyone for next month's article.
Nature Notes for April 2003 Hilltop News The month of February ended as it started with significant rainfall. Over the month as a whole around 1 inch or 25mm fell, well below the UK average for February of 38mm. The middle of the month provided a cold snap of sorts with some bitter north-westerlies and accompanying wind-chill. The 18th was the coldest day, which at 7am was -7.7°C, and the warmest day with 14.9°C at lunchtime was the 27th. So far, March has begun to tempt us with warm weather which no doubt warns us that it will go out like a lion. Interesting to see if we have a gale blowing as the intrepid distributors of this newsletter are on their rounds! Last month I mentioned how plants and animals can act as indicators of climate change. The bumble bees started making appearances earlier this year: 2nd March (15th March 2002). Hawthorn and other early trees look like being about a week behind the records for last year. By the time you read this there is a possibility that frog and toad spawn will have arrived in the local ponds and newts should be making an appearance. Now here's the clever bit, which you might want to involve the younger members of the family in. If your frogspawn is in the middle of the pond, there will be a drought, if it is around the edges, expect wet weather. If you think about it, there is a logic here but don't ask me how the frog predicts the weather. I look forward to hearing of any frogspawn sightings, including the date as well as where it is located! 
April is the month when the smaller nesting birds are in full swing. But its the larger birds which also catch the attention. great-spotted woodpeckers will still be asserting their authority by drumming their favourite decaying tree whilst their relative the green woodpecker will help aerate your lawn in search of ants. The cuckoo should be heard from towards the end of the month heralding the arrival of Spring. Red kites, which have been introduced to the Chilterns, are thriving, and on a recent journey through Watlington and Christmas Common I spotted five at close range. I have seen them a couple of times this year circling overhead in these parts and now that their numbers are growing the increased competition should encourage more to head in our direction. Look out for very large birds soaring with ease. They can be distinguished from buzzards by their larger size, deeply forked long tail, reddy-brown plumage and white patches under the wings. Let me know if you sight any. 
On warm sunny days in March and April brimstone butterflies emerge from hibernation and should provide an indication that average ground temperatures are on the increase and the growing season has started in earnest. So get those 'second earlies' (potatoes) in quick. 
Badgers become more active this month. Cubs will be born around now so look out for food gathering activity or listen out for their characteristic grunting at dusk, especially on warmer evenings. Once again I would welcome contributions or ideas from anyone for next month's article. Chris Brown tel 758890 email chrisbrown@rayshill.com
From Hilltop News March 2003
By the time you read this January will be a distant memory. Meteorologically speaking temperatures were above average although, I suspect the highlight was the snow which came at the end of the month. For once though, we escaped the blizzards which chose to fall on Amersham instead and hence the excessive coverage in the Bucks Advertiser about the chaos a bit of snow causes! We think we get our fair share of rain up here but actually we fare much better than most and during January notching up a mere 3 inches or 85mm (3.75 inches in Jan 2001). It has more to do about how it falls rather than how much, I guess. All but a drop or two falling on 4 particular days including New Year when the Vale once again reverted to type for a few hours after lunch. The warmest day was 25th (12.5°C). Whilst the coldest was at 5am on 12th (-8°C) to which should be added a wind chill of -9°C! So far, February can be described as 'damp but uneventful'. As Michael Fish would say hurricanes are not expected! But more on this next month. 
Global warming (GW) no longer makes the headlines. Notwithstanding more immediate world crises this is perhaps also because we are now conditioned into hearing about its impact on the climate and hence the distribution and behaviour of our native flora and fauna as well as the growing season of crops. In reality single events or one-off sightings of unusual wildlife cannot be attributed to the GW phenomena. However, it has sparked a renewed interest in the science of phenology, which is the recording of events connected to the climate. Records have been collected for over 300 years (e.g. Gilbert White). In the last 100 years there has been a 0.6°C increase in world temperatures. This is sufficient to encourage some plants and animals to extend their ranges northwards and will be more significant 600ft up in the Chilterns than in the Aylesbury Vale for instance.
In 2000 the UK Government started using such observations to track climate change. I thought you might be interested in a few records from March 2002 for particular species for the 'Hilltop Villages' and UK average dates for some previous years. Whilst it does not provide a basis for predicting when the sea will engulf most of East Anglia it might encourage you to look out for when these events occur near you this year. Make a note of when you first cut your lawn this year. The UK average last year was 15th March!
For more information about these records and how you can contribute visit www.woodland-trust.org.uk/phenology. Once again I would welcome contributions or ideas from anyone for next month's article. |
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