Nature Notes 2006

December 2006

Hibernation

Winter was a long time coming but by mid December I expect we will have had a series of frosts, regardless of the best efforts of global warming. Our wildlife will have adapted to this unproductive season in a variety of ways, the most intriguing of which, is hibernation. Very few of our mammals do actually hibernate but Hedgehogs and Dormice are the classic winter sleepers and until the spring they will have reduced their body temperatures and heartbeat rate to a barely survivable level, so that the reduced metabolic rate enables them to survive on their fat resources alone.

Hibernation is not a long sleep, from which animals can quickly recover if necessary and they are at great risk from disturbance and predators during this period. However hedgehogs at least, regularly emerge from hibernation several times during the winter - it takes four to five hours for them to regain their functional body temperature - only for them to go back into their dormant state, perhaps after a brief stroll.

Badgers and Grey Squirrels do not hibernate, but they do rest for long periods during adverse weather conditions and all other British mammals with the exception of bats are active normally during the winter. It is the availability of food that determines the right strategy and in mild winters with plenty of earthworms readily available, Hedgehogs are quite able to go without any hibernation at all.

Many insects use hibernation as a winter survival strategy, including those late-flying Red Admirals and Brimstones and also some moths and whereas most Lepidoptera pass the winter in their egg or larval stage, these species can take advantage of the early spring sunshine and the un-tapped nectar sources of primrose and violet.

November 2006

Winter Birds

Feeding wild birds during the winter months has become widespread practice and is far more refined than the throwing-out of household scraps that constituted garden bird feeding twenty years ago. Peanuts in their shells, threaded onto a string, half a coconut, or peanuts in a red mesh bag were the most generous offerings then, and when they were consumed, they were only occasionally replaced . Blue and Great Tits were the targets but House Sparrows and Starlings soon mastered the art.

To many people now, the continuous availability of a diverse and nutritious food supply is a high priority. Mixed seed, shelled peanuts and a steady supply of sunflower seeds - black-shells because Greenfinches prefer them or shelled altogether because tidy gardeners prefer them! - these are the basics. A bird table with a range of scraps and a scoopful of mixed seed, for the less athletic or competitive visitors such as Robins and Collared Doves is the next step. And for the crème de la crème - those bouncy and colourful entertainers, the Goldfinches, a special feeder filled with Niger seed is de rigeur! These tiny black seeds are guaranteed to attract this delightful finch to most gardens (and result in previously unknown yellow blooms, it has to be said!).

The issue of all this flocking together by birds not of a feather has raised concerns of bacterial infections becoming widespread and the regular application of a mild disinfectant is recommended. Please don't confuse bird-flu (a virus) with this concern and cease feeding altogether, as the delight the visitors bring and the benefits they accrue, currently outweigh any potential disadvantage.

October 2006

Moths and Mice

2006 has been a great year for migrant Lepidoptera. Painted Ladies were the most evident, especially during the hot weather in July, but they were accompanied at the buddleia by Silver Y moths in even bigger numbers. These fly by both day and night and migrate here from the continent. There have also been large numbers of other moths in Rushcliffe that have flown from Europe including Bordered Straw and Scarce Bordered Straw, Humming-bird Hawk Moth and Rusty Dot Pearl.

The Harvest Mouse is our smallest rodent; an adult weighs about the same as a twenty-pence piece; their scientific name, Micromys minutus, means “smallest tiny mouse”. They have extremely short life spans and although they may produce three or four litters of around five babies in a season, it is touch and go that any will survive the winter. This means that they can be present in an area one summer and absent for several subsequent seasons. They are very difficult to see in the wild, requiring luck whilst doing some grassland management, or extreme patience and quietness to study them at a known locality. Their presence or otherwise is most easily established by searching for their used breeding nests which are tennis-ball sized spheres of woven grass, some distance above the ground. The time to do this is in the winter when surrounding vegetation has died back.

I mentioned in a previous note about signs of a return of hedgehogs and I’m pleased to report the presence of one in my Keyworth garden for the first time in about ten years. I was less happy to find two grass snakes that had suffered the fate of many hedgehogs and been squashed by cars, on the road from Wysall to Costock. It’s nice to know they’re around though.

September 2006

Bird Migrants

Swifts, those aerial acrobats, with their joyful and exuberant screams as they chase over our houses will have gone now. They are one of the latest summer visitors, not arriving here until May and are definitely one of the earliest to depart. They are beaten only by the adult Cuckoos, who, job done by June and no responsibilities remaining, wander their way southwards at a leisurely pace through the height of the summer. If you see a cuckoo as late as August, as well you might, particularly at the coastal migration points, it will be a juvenile, embarking on a journey to its wintering grounds in Africa, south of the Sahara. Unaccompanied by any experienced navigators, this is a supreme example of "instinct" that remains to be understood.

By October, here in Rushcliffe, we can experience the best of both worlds: the lingering summer migrants such as Swallows and Willow Warblers and the incoming thrushes that have spent their brief summer in Scandinavia. Both the Redwing and Fieldfare do breed in Britain in small numbers, mainly in northern Scotland, and the former also spends the summer in Iceland, but to most of us they are a sign of shortening days and their occasional visits to gardens are a good reason for providing berry-bearing shrubs.

The first indication of immigrant Redwings is their distinctive monosyllabic whistle, delivered during their nocturnal migrations and often first noticed by the alert pub-goer on their way home around midnight.

The lack of berries on the overly-managed farm hedgerows, means that they have to resort to feeding in the fields, far earlier nowadays than used to be the case: the tractor-mounted flail cutter and an expectation of tidiness in our countryside, threatens the future of these winter farmland birds that are so characteristic of the Rushcliffe countryside.

August 2006

Black Poplars

Black Poplars are probably Britain's rarest native tree and there are just a handful in Rushcliffe. They are scattered around the borough but the most interesting must be the stand of trees along Fairham Brook near Widmerpool. These are growing in what is their typical habitat since their seeds only germinate in wet mud. These however are all females so there is no cross pollination and although they are very old they regenerate with new growth after they have keeled over.

Black Poplars were used to make arrows found on the Mary Rose and were planted as boundary markers. The landscapes that Constable made along the Stour, including the HayWain, feature them. They are recognisable by their weeping branches with upturned tips and the low crown. Close up, their heavily fissured bark with craggy burrs and bosses is distinctive. They ceased to regenerate themselves from seed when widespread agricultural drainage denied them the wetlands they need and most trees that are left have been struck from cuttings of males. This is because the female trees produce copious quantities of white fluff which is unpopular in managed locations.

Surprisingly though, they are not protected as a species, apart from the general rule that it is illegal to take or destroy any wild plant without the permission of the landowner. So if you have the space for what will eventually become a big tree, consider the Native Black Poplar (beware of hybrids). They grow happily away from water and you will have acquired a tree with a great history and folklore.

July 2006

Colonisers

Hedgehogs seem to be making a comeback judging by the number of squashed ones now littering the roads. For the last decade or so I’ve been convinced that their numbers in Rushcliffe had collapsed with very few road kills and none in my garden where previously they’d been seen or deduced from their tell-tale droppings on the lawn. Nationally this perception is only just receiving attention with the Mammal Society asking people to send in records of road kills. It seems perverse to estimate the population by counting how many dead ones are seen!

Hares seemed to be very few and far between in the 1990’s but after Foot & Mouth in 2001 they now seem to be very regular once again. Are diseases responsible for these cycles?

The most obvious change in populations in my lifetime is with birds and the return of the Sparrowhawk and the Buzzard. Both now nest throughout Rushcliffe although they can be elusive during the nesting season. Collared Doves seem to have been around forever but they didn’t even make it to the country until the early 1950’s.

Populations also change in the insects: Magpie moths used to be one of the commonest moths attracted to house lights and now they are virtually absent even from powerful light traps. Other species, associated with the Cypress family are expanding their range because of the now abundant leylandii hedges; Blair’s Shoulder-knot is now common in Rushcliffe.

June 2006

Scots Pine

There's a twenty-year old Scots Pine tree in my garden. It’s still quite bushy so the lower branches can be inspected for wildlife and recently I found two species of ladybird that are normally only found in coniferous woodland. This is in addition to the Pine Sawfly and two moths – Pine Beauty and Pine Hawkmoth which are obviously associated with it. What better illustration can there be to show how gardening for wildlife can be successful and that if we provide the habitat, species will find and colonise it. In January, a Goldcrest foraged in the tree for a week, probably gobbling up small spiders which for all I know are restricted to Scots Pine as well.

As well as a good range of native plants, every wildlife-friendly garden should have a pond (child safety permitting). 12-year old Alex Glenn and his younger sister, Minty, had a wonderful time recently dipping for newts and frogs and presented me with a Smooth Newt that had such a pronounced crest we thought it was a Great Crested Newt for a time. The pond has always contained Smooth Newts and the males of this species have a crest, but theirs is nothing compared to the dragon-like embellishment of their larger and rarer cousin. 'I've seen some smooth newts but this one beats them all!' as Minty said at the time!

Footnote

A more careful identification of the pine found it be a Corsican Pine Pinus nigra

May 2006

Moths

The French call moths, “papillons de nuit” i.e. butterflies of the night, which is much nicer than our term, which is a dowdy sounding word, and inevitably brings to mind the dowdiest moths. Some of them are dull indeed but many are stunningly beautiful as their English names, given to them by the Victorian collectors imply: Garden Tiger, Burnished Brass, Waved Umber, Oak Beauty and Merveille du Jour for example. Those Victorians were objective in their epithets however; they christened one the Clouded Drab!

The “mothing” year sees a progression of different species on the wing between March and October, and mid-summer is the peak period for the most spectacular, for the hawk-moths include our biggest moths with wingspans of around 90mm.

You may be astonished to learn that Elephant Hawk, Poplar Hawk and Eyed Hawks are not at all uncommon. If you grow plants that have nocturnal scents, such as night-scented stock, or flowers like Nicotiana, which can only be pollinated by long-tongued specialists like the Humming-bird Hawk moth, you may come across them without the need for specialist light traps.

A restless moth plummeting around your bedroom on a sultry night might well be annoying, but when it has settled down, do spare it a second-look – you may be surprised by its subtle beauty.

April 2006

Snakes

Rushcliffe is the best part of Nottinghamshire for Grass Snakes. They are totally harmless to people and would love to live their lives undisturbed by us: in return they would never bother us at all.

In Nottinghamshire, two of Britain's three species of snake used to be common; the Adder and the Grass Snake, but the former is virtually extinct and now restricted to drier sites away from Rushcliffe. If you were to come across a Grass Snake and it was lethargic enough to let you pick it up, it would smell a bit unpleasant for a while and glide through your fingers: If handled considerately it would soon adjust to your warmth, cease giving off its defensive odour, and become quite relaxed. They are fully protected by law so this would technically be an offence.

April and May are the months to see our reptiles, as they emerge from hibernation, but if you come across a snake in Rushcliffe, remember - it almost certainly won't be an Adder, it will do no harm to anyone and would be pleased to be left alone.

The earliest spring flowers are mainly in woodlands where they take advantage of the sunlight that gets through the barely foliaged trees and where pollinating insects have shelter from cold winds.

March 2006.

Bird Song

This is a wonderful time of year for inspiring the amateur naturalist to get out-and-about! Bird song is reaching a peak, though most of the incoming summer visitors from Africa won't arrive until late April. That makes the next few weeks the ideal time to get to grips with the songs and put names to them without grabbing the binoculars, because apart from Willow Warbler and Chiffchaff, the songs will be from those species that have been familiar over the winter.

The first butterflies are on the wing too. The earliest; Small Tortoiseshell and Brimstone, hibernate through the winter and emerge on the first warm days. Comma and Peacock also fly early in the year but their big numbers appear in the late summer from the eggs produced in the spring.

Rushcliffe is a heavily farmed rural area with pockets of exceptional natural interest, many of which are nature reserves, but the farmland looks set to become more wildlife-friendly with the Countryside Stewardship Scheme. This should make the local footpaths and by-ways even more worth exploring and the long drive to the Peak District and the east coast less worthwhile - good for the environment on all counts and good news for us too.