Roving Records - Land East of the Railway Line: 10/05/13

On Friday I carried out a check of our dormouse boxes in the LERL; sadly no further evidence of their nesting activity. However the boxes are certainly being put to good use by the Blue Tits and Great Tits...

At the moment over 1/3 of the boxes contain either Blue Tit or Great Tit nests

I was crouched down while making some notes and when I looked up I don't know who was more surprised, me or this male Roe Deer...

Hazel coppice understory, a dense Bluebell carpet and a curious Roe Deer in Horleyland Wood

It wandered in a large circle around me and casually sauntered off, another male not far behind it. I must have blended in pretty well; my clothing has definitely become more 'grungy' since I first started here (whether that's a good thing or not.) I'd like to think I'm becoming a better naturalist; most recently I have acquired some collecting pots, bought a utility-belt (i.e. a bumbag) and I've mostly stopped caring about getting my feet wet.

Common Frog tadpoles in the shallows of Pond 3 (I like our exciting pond names)

I was checking the final Dormouse box when I spied this well-hidden nest between the boles (thick stems) of an old coppiced hazel, proving it to be rather useful habitat. They are likely Blackbird chicks and might have a harsh appearance just now, but their eyes are beginning to open and in a few more days their feathers will be pushing through...

Blackbird chicks in a nest

 Comma Butterfly (Polygonia c-album) in Horleyland Wood. These guys are territorial; it flew laps around me and always landed back at this spot

  (The butterfly formally known as Cabbage White) a Large White Butterfly (Pieris brassicae), over in Goat Meadow

It was a good week for butterflies as well as other invertebrates; the first Large Red Damselflies have been taking to the wing over in the North West Zone, Orange Tip and Peacock Butterflies have been busy along the River Mole, Gatwick Stream and our woodland margins. I was chuffed to get a photograph today of one of these beasties out on the move, they rarely keep still long enough to snap...

A rather conspicuous stalker...

A few days previously Scotty Dodd, Surrey Wildlife Trust's expert entomologist, visited this site with me in preparation for summer invertebrate surveys. I netted one of these and took a picture before releasing it back out. Scotty identified it as a type of Cuckoo Bee, most likely the species Nomada leucophthalma.

Potted for a close-up of this cool little wasp-like bee

No pollen-collecting bags on her back legs... this tiny sneak travels light!

Although very wasp-like in appearance with its shiny hairless abdomen, this is actually a type of bee and a 'cleptoparasite' of other solitary bees... Basically Nomada has a rather sinister lifestyle which involves following other foraging bees back to their burrow, then sneaking in to lay their own eggs on the hard-earned food supply. There were a plenty of these tiny little lurkers about, which also indicates a good size host population...

I spotted many of these tiny burrows along the edge of the path in the woodland strip - likely to be Nomada's target host

The host solitary bee in question - Andrena clarkella, eyeing me suspiciously

This little lady is what the Nomada are busy hounding - an early ground-nesting bee with the lovely name of Andrena clarkella. They are an early season solitary bee and mainly collect the pollen of willow flowers. It was great to take a moment and watch the bustling activity of all these different invertebrates, deeply engrossed in their individual missions while the good weather held out.

Brown Tree Ants (Lasius brunneus). They nest in the old deadwood of trees, probably in one of our large veteran oaks of the woodland strip

Then a bonus end to the day is finding your only pencil where you carefully left it on the footpath.

Gatwick’s habitat mosaic: The science stuff

The names of our two conservation sites reflect the (sometimes infuriating) tradition of airport acronyms...

NWZ: situated just above the western end of the airfield

 LERL: to the south-east of the South Terminal

However they are usefully descriptive names and 'ell', 'ee', 'arr', 'ell' (LERL) rolls off the tongue after a while. These two areas are made up of mixed habitats containing their own related niches of wildlife. Our aims are to conserve all of these habitats and enhance them. Were it not for the airport then these buffering pockets of land would probably not be here, instead being given over to housing development or agriculture.

Brockley Wood’s south-eastern edge

I am often asked why we go in and carry out such heavy duty habitat management; it can seem counter-productive hacking back the brush and young woodland instead of just leaving it up to nature. In the simplest terms, changes in land use and development by people have caused our landscape to become very fragmented. Ecosystems no longer function in the usual way and the isolation of habitats such as woodlands, lakes and grasslands tends to result in their containing fewer species and a less diverse structure. For example, if the last remaining field maple in a small woodland fragment died out, there would be less chance of re-colonisation from the surrounding area if there is no other nearby woodland. A few dominating species in a small area are also more likely to take over and out-compete others. So we intervene to maximise the diversity of the land we have left and prevent a few species from becoming overly dominant (in the context of the wider landscape).

Bankside coppicing along Man’s Brook, North West Zone

Recently we have begun rotational coppicing of shrubs and trees (ie. cutting back to ground level) to provide a range of different-aged scrub as it regrows. A richer variety of habitats is beneficial for biodiversity as it will suit a wider assortment of species. However, if coppice stands are neglected they can grow up again into tall canopy cover, shading out the smaller ground flora. If hedgerows are left uncut, they can grow out and become straggly, dying off in the centre and eventually becoming lines of large trees. Coppicing helps to keep the integrity of a habitat and maintain it in a medium-aged state.

Coppicing can affect environmental conditions such as ground temperature and light levels

With conservation pressures ranging from small scale to large, our best course of action is to maintain a high level of structural diversity in a dynamic system, so that these many small havens will make up a healthier whole and as many organisms will benefit as possible.

There are many very good reasons for preserving the biodiversity of our planet … I am not going to list them all here, instead I will refer you to this link (though I honestly don’t mind if you want to skip over point no.9): http://www.natureserve.org/consIssues/tenReasons.jsp

The thing which resonates the most with me about conserving biodiversity is Aldo Leopold's statement in ‘A Sand Country Almanac’:

   “ - if a missing cog or belt can render a car’s engine useless—how much more might a missing organism affect the health of an ecosystem whose complexity is overwhelming?”