Wednesday 26 June 2013

Summer Breeding Bird Survey - NWZ

With Tom Forward of Gatwick Greenspace Partnership

River Mole grasslands along our Breeding Bird Survey transect

Friday was another one of those days where we were literally tripping over wildlife. The River Mole grasslands (just north of the airfield) are looking their best right now with many diverse and beautiful grasses in flower. I had never really noticed how rich and striking grasslands can be until last year after attending the grasses, sedges and rushes course with the Sussex Wildlife Trust. It was almost worth putting up with the hayfever! Almost.

NWZ Grassland along the diverted section of the River Mole

Crested Dog's Tail grass (Cynosurus cristatus) in flower

Quaking Grass (Briza media) in flower

Grass Vetchling (Lathyrus nissolia)

Tom can really shift it through the long grass and I have to run and jump to keep up, no time for my usual bird survey biscuit-break. When being inundated by the sound of lustily-singing territorial males the challenge is to train our ears and identify each particular bird song or call. We had just marched past what looked like a couple of manky old leaves stuck in the grass when Tom did a double-take, then uttered something possibly in French...



A pair of mating Eyed Hawk-moth (Smerinthus ocellatus)

These cryptic individuals are an impressive type of Hawk-moth which when disturbed will show a pair of brightly coloured eye-spots on their under-wings... see Eyed Hawk-moth - UK Moths. They were pretty absorbed by their own 'activities' and so didn't pay us much attention. I am just starting out with moth identification and it is really addictive; I'm like a lumbering T-rex in wellies, chasing anything which moves...

Blood Vein moth (Timandra comae)

I managed to collect this in an insect pot. Then nearby Tom yet again spots something cool roosting up in the grass, well-camouflaged among the scattered white rose petals and the patches of Cuckoo-spit...

White Ermine moth (Spilosoma lubricipeda)

Anyway, back to the birds! A new species to appear on the survey list for the NWZ was Garden Warbler, the song of which to me sounds like something in between a Blackcap and Whitethroat. I thought I had been hearing this about the place recently and so was glad Tom could finally confirm it for me:

Another new species on our timed survey was Ring-necked Parakeet; these have been established in the Gatwick area for quite some time. This is a species not native to Britain but are the result of escapees from over 40 yrs ago, as a result they are now very common around London and the south east.

Some of the usual suspects were conspicuous in their absence including Meadow Pipit, Lesser Whitethroat, Mallard Duck, Carrion Crow and Common Buzzard, which I had seen here just 2 days earlier. Sadly a no-show for Kingfishers too but no reason to think they might not still be around. Another thing I had thought I'd heard the week before was a lone Cuckoo in Brockley Wood which called just twice. Apparently by now they might be winging back down south on their way to more continental climes.
Here are a few of the other niceties we have seen:

 Ragged Robin (Lychnis flos-cuculi)

Roosting female Broad-bodied Chaser dragonfly (Libellula depressa

Crosswort (Cruciata laevipes)

Dog poo bin across the river

Our bird species total came to 30 on the timed part of the survey; just under our average count. You can see our day's species list here: NWZ Breeding Bird Survey June 2013

Wednesday 19 June 2013

Bat-Air Traffic Control

Last Friday an odd thing happened; the wind dropped, the clouds parted and the evening air was warm... The bat walk I had organised actually went ahead and 8 of us were led through Upper Picketts Wood by Martyn Cooke of Surrey Bat Group (also an air traffic controller here at Gatwick).

Torchlight trek through Upper Pickett's Wood

Gatwick's Land East of the Railway Line

As the sun was setting we stopped off at Roll's Farm, an old abandoned farm house by the sewage works. With its wild, tangled garden and loose roof tiles it really looks like the perfect bat haunt. Our bat detectors were on and we were busy chatting when suddenly a series of louds clicks swept us by... A Common Pipistrelle (Pipistrellus pipistrellus) was on the wing and loudly echolocating! Martyn was able to show us on his Anabat detector screen the 'hockey-stick' pattern of a Pipistrelle call:

The call of a Common Pipistrelle bat (Pipistrellus pipistrellus) which peaks between 45 and 50kHz

People were excitedly pointing but annoyingly I still couldn't see anything. It was getting frustratingly dark - suddenly I saw my first Pipistrelle bat as it veered around us, much lower and closer than I had expected! No chance of them bumping into us though as these tiny predators are aerial experts, catching their insect prey and eating on the wing. Martyn said they were probably feeding on midges which our group was attracting in (and beginning to feel!) I did my best to get a photo, if you look carefully you can just about make out the tiny bat as it shot past...


Ok a little joke, I didn't attempt a photo. However it was a great privilege to see and hear these usually unnoticed creatures. We heard only Common Pips but then at the very end of the walk we heard a Soprano Pipistrelle (Pipistrellus pygmaeus), which were only recently declared a separate species. Martyn is a brilliant source of bat info and has some great stories, including the only reported 'bat strike' in the UK... (Disclaimer Alert: bats pose zero threat to aircraft!)

Light Emerald moth (Campaea margaritata)

We also tested out torching for Great Crested Newts at our two woodland ponds; we were able to make out 2 large female G.C.N. and 1 small male. Also spotted were several Smooth Newts and 2 Common Frogs. While people were using their torches I was attempting (and mostly failing at) bare-handed capturing of moths drawn in by the light. I did manage to grab 2 macromoths which I potted and took home to photograph in the daylight.

Light Emerald (Campaea margaritata)

Common White Wave (Cabera pusaria)

Common White Wave (Cabera pusaria)

I feel a bit mean that I haven't shown any pictures of a bat, so here is a photo of two lovely little Common Pipistrelle, one of which a friend of mine rescued in Copthorne back in 2007. We took it over to the Jenny Clark of Sussex Bat Group who rehabilitated and released it back into the wild...

'Boost' the female pipistrelle and her new buddy 

You can find out about all of the UK's different bats species here: Bat Conservation Trust

Wednesday 12 June 2013

Reptilian refuge

Britain's reptiles simply don't deserve the bad rep given by that larger and more aggressive species Homo sapiens. For sure there is something about the way a snake moves which can stir a primal fear inside us, but this is just a throw-back to a time long ago when it paid to be wary of a certain few venomous species. 

Young Grass Snake (Natrix natrix), probably a yearling - Photo by Natalie Kay. These guys are not 
venomous and are completely harmless (unless you happen to be a frog or newt).
 
The reason you don't often see reptiles out and about in the countryside is that they flee the scene before you stumble across them; snakes can find themselves on the menu of everything from Carrion Crows and birds of prey to Badgers, Foxes, Cats and even Hedgehogs! If they don't move out of the way that's because they are hoping you haven't spotted them. UK reptiles are extremely benign and our only venomous species, the Adder (Vipera berus), rarely bites. In the last century only 12 fatalities were reportedly due to Adders, which is much fewer than deaths caused by wasp stings, cows and stray golf balls (my new phobia!)

Grass Snake skin found under a refugia, Grassy Slope, North West Zone.
Apparently males slough their skin twice a year, females only once

We survey for reptiles at Gatwick by placing out roofing-felt mats or 'refugia', providing a safe place for these secretive and cold-blooded beings to hide away from predators while they warm up with the sun's heat. It is kind of like a solar charging mat or iPod docking station.

It feels like Christmas (in a good way) when I first lift up a mat...

Grass Snake trying its best to blend into its surroundings

Grass Snakes tend to be olive green in colour, have disconnected black stripe markings down the length of their bodies and a distinctive yellow collar at the base of their heads. We seem to have a healthy population here though I am sad to say that I have never seen an Adder at Gatwick... nor Common Lizard (Zootoca viviparaor Slow Worm (Anguis fragilisfor that matter! As we are focusing our habitat management on as many different species as possible there is always the possibility of future appearances. In the meantime here are the other things which have been taking advantage of the refugia...

A young vole, not sure which species

 Glow Worm larvae (Lampyris noctiluca) in Ashley's Field

Rustic Wolf Spider (Trochosa ruricola)?

A tiny Common Toad (surely a risky business sharing refugia with Grass Snakes!)

Occasionally I am also lucky enough to be walking about the place and spot a Grass Snake out in the open...
Blending in with the grass, living up to the name. North West Zone

At home in the water - Land East of the Railway Line. I'm particularly proud of this photo - luckily it didn't see me and I was able to get this shot just before it about-turned!

Reptiles are protected for a reason; their numbers have suffered sharp declines in recent decades and their habitat is continually being removed and developed. If you are fortunate enough to come across one of these fascinating beasts please just let it do it's thing and enjoy that rare moment.

For more pics and info on Grass Snakes: http://www.arkive.org/grass-snake/natrix-natrix/

Wednesday 5 June 2013

Record-breaking recorders

In the last 2 weeks I have been on holiday, been pretty unwell and been extremely busy preparing for the initial Biodiversity Benchmark audit here at Gatwick. As a result I haven't been able to get out in the field much, but happily I got my natural history fix last weekend after a biological recording day at the Knepp Estate in West Grinstead.
Mark Telfer and other pan-species listers, beating vegetation and catching invertebrates

Here I met an eclectic bunch of diligent, passionate and frankly hard-core naturalists, some of who are professional conservationists or ecologists, many who simply love the natural world and set themselves the lifetime challenge of observing as much of it as possible. These are the pan-species listers and I thoroughly enjoyed chatting with them to get a snapshot into their pursuits; from lichens and fungi, to beetles, birds and everything in between.

Mark using a pooter to collect up the tiny deadwood beetles for identification

 These guys and girls contribute an incredible amount to species records around Britain, often collecting data on lesser-known organisms and even discovering new unrecorded species. (Some may call it odd, I call it diligence that they travel so far in order to find a not-so-fresh deer carcass, donning their gloves and giving it a thorough cavity search for carrion-feeding invertebrates dwelling inside...) You can meet them and follow their progress on Mark Telfer's website: http://markgtelfer.co.uk/listing/
   I am rather new to ecology and seemingly much too distracted and indecisive right now to choose one species group to focus on learning. Below are my photos from the weekend, a very small sample of the showier species which we recorded:

Beetles:
A wasp-mimicking species of Longhorn Beetle (Clytus arietis)

Black-headed Cardinal (Pyrochroa coccinea)

Malachite Beetle Malachius bipustulatus (this one gave me a tiny nip)

Dragonflies and Damselflies (netted with my new insect net):

Azure Damselfly (Coenagrion puella)

Male and female Azure Damselflies in tandem (Coenagrion puella)

Female Scarce Chaser Dragonfly (Libellula fulva)

Blue-tailed Damselfly (Ischnura elegans)

Large Red Damselfly (Pyrrhosoma nymphula)

Moths (mostly from the overnight moth traps):

Brimstone (Opisthograptis luteolata)

Longhorn Moth (Nemophora degeerella)

Lime Hawk-moth (Mimas tiliae)

Pale Prominent (Pterostoma palpina)

White Ermine (Spilosoma lubricipeda)

Swallow Prominent (Pheosia tremula)

Poplar Hawkmoth (Laothoe populi)

Iron Prominent (Notodonta dromedarius)

 A rewilding project has been in place at the Knepp Estate for 13 years, based on a natural grazing regime in the old agricultural grasslands and the restoration of the River Adur floodplain to its natural function. This involves stepping back from hands-on land management, intervening as little as possible and letting nature dictate what happens. The idea is then to annually record the species and observe any of the changes over time in what turns up.

The wild Exmoor Ponies which freely roam the Knepp Estate

This exciting and long-term project contrasts greatly with our here method at Gatwick: our habitats are very small, fragmented and at times affected by airport operations, so we have to intervene in order to keep the ecosystems functioning. It has all been a great education for me on the different methods of wildlife conservation and countryside management. You can read more about Knepp Wildland project here www.knepp.co.uk