US social scientist Kenneth Boulding : ‘If you believe exponential growth can go on in a finite world, you are either a madman or an economist’.

Saturday, 27 November 2010

27/11/10: Seeing the wood and the trees

A selection of tree photos taken today ....

Tree with a skirt of leaves - on the lower branches, and on the ground. Former Pitch and Putt golf course, north side of Bursted Wood, Barnehurst

The yellowed leaves of Sweet Chestnut continue to light up Bursted Wood, Barnehurst, in late November

Yellowed Sweet Chestnut leaves stand out against the dark green of an ivy-clad tree, Bursted Wood, Barnehurst

Tree silhouettes, Hall Place North, south of Bexleyheath

A row of trees stretching down the hill at Hall Place North, silhouetted at dusk

A deliberately blurred shot of a 'naked' tree at Hall Place North

Dead tree, Martens Grove

Trees in the dark, Martens Grove

27/11/10: Parakeet parade over Gravel Hill

I was heading for Hall Place North at about 4 p.m. Four groups of Ring-necked Parakeets flew over Gravel Hill in quick succession, heading roughly north-west or west - 14, circa 15, 25-ish and then another group of about 15.

No sign of any Redwings here yet.

Thursday, 25 November 2010

25/11/10: Fine stand of Annual Nettle in North Heath alley

Here's part of the largest and most luxurious stand of Annual Nettle (Urtica urens) I've yet found, growing in an alleyway in Northumberland Heath, London Borough of Bexley.

The leaves of the plants in this colony are particularly sharply and attractively 'cut'.

Saturday, 20 November 2010

20/11/10: (On the way to) Richmond Park

Up early to get over to Richmond for the LNHS Ecology and Entomology field trip in Richmond Park, looking for invertebrates under dead wood.

On the way to Barnehurst station, 23 Ring-necked Parakeets were seen flying north-east.

On a wall by a noticeboard in Terrace Gardens on Richmond Hill, I found my first specimens of Rusty-back Fern in London, a total of 24 plants.

Rusty-back Fern or Scaly Spleenwort (Asplenium ceterach or Ceterach officinarum) , Terrace Garden, Richmond, south-west London, growing with Hart's-tongue Fern

There was a good turnout of 11 members and the legendary Dingo the dog. I didn't make notes on the invertebrates found.

LNHS members studying invertebrates associated with dead wood. Dingo isn't very interested .....

Richmond Park panorama, with anthills in the foreground

Sulphur Tuft fungus (Hypholoma fasciculare)

There were a number of Jackdaws around and a Common Toad was found under one of the logs lifted up. Sheep's-sorrel was most prominent on top of anthills. Other small plants included Common Stork's-bill, Parsley Piert and, at one location, what I think was quite a lot of Bird's-foot (Ornithopus perpusillus).

Thursday, 18 November 2010

18/11/10: Counting Starlings over Thames Road Wetland

OK, so not quite up to the numerical standards of tonight's Autumnwatch, but whenever I see a fair few Starlings I try to get a count, given that I know indigenous numbers have declined dramatically.

On November 16th, at dusk, I was particularly pleased to see a flock wheeling several times over Thames Road Wetland (of which I am Site Manager), and I was able to get a 'side on' mobile phone camera picture - albeit a rather distant one.

The speed of the birds and size of the flock meant that I'd been unable to get a visual count estimate of the numbers of individuals at the time, so I cropped the photo down to the margins of the flock and printed it out. Whilst the image of each bird was not particularly sharp, I was able to number all the birds and, with reference back to the somewhat sharper on-screen image, resolve how many birds were present in the surprisingly few image 'overlaps'. I came up with a total of ................

231 birds (or possibly 230)

Interestingly, this is considerably more than my 'on site' guesstimate, which I rejected at the time, and also for an estimate based on application to the photographic image of the sort of rapid, rather 'jumpy' and 'finger-pointing' count I've used in the field before, which came up with about 80.

So if you want to get a more accurate count for a flock of birds that you can get within one frame - and still blow up to a decent size and reasonable resolution - you don't need a fancy camera to do it.

Here, as a matter of interest, are the original photo, and the cropped version that was printed out to do the numbered count :-

Flock of Starlings over Thames Road Wetland at dusk, 16th November

Starling flock cropped and enlarged out of the preceding photograph, printed out, then counted by numbering all the individuals in the resulting image. It still doesn't look like 231 to me ....... but cameras don't lie!

Tuesday, 16 November 2010

16/11/10: Cray and Thames Road Wetland in the mist

The first hard frost (that I've been up early enough to see, anyway) and, consequently, as the sun came out and started to burn it off, a goodly amount of mist.

Nothing in the way of new species to report at this time of year, as might be imagined (one lives in hope of a Bittern and Waxwings ....), but there was the wintry sight of a Pied Wagtail on the pavement at the Thames Rd end of Crayford Way, and also at the junction of Barnes Cray Rd and Maiden Lane a short while later (could have been the same individual). Several Chaffinches were along By-way 105 by the river.

3 Ducks were on the Thames Road Wetland 'lake', one of which was a male Teal. They 'spooked' rather easily and all flew off together, so the other two were probably female Teal.

There were a couple of Robins about on the site and one or two Dunnock.

Some Coltsfoot - not previously noticed, as it was hidden away behind some concrete barriers - was found in the north-east corner of the site.

I spent about 4 hours expanding and deepening my banks-and-ditches system in the compacted, gravelly soil in this part of the site, so as to increase cover, especially for heat-loving insects. But it's hard going and a slow, rather tiring, wrist-aching process with a mattock and spade. Unlike my garden Robins, which would have been down to have a look, the residents here took no interest. Perhaps they already knew how poor the ground was for worms - I only found one in the whole dig!

Here, then, are some of today's pictures of the Cray and its surroundings, and the Thames Road Wetland ........

River Cray, looking downstream over the Maiden Lane bridge parapet

Looking south from the River Cray embankment, just downstream of Maiden Lane bridge

Thames Road Wetland in the mist, frost on the ground, looking east towards the railway line

Wintry afternoon sun slants across the River Wansunt where it transects Thames Road Wetland, lighting up the dying golden leaves of a Poplar by the River Cray (centre, in the distance)

A ditch at the eastern end of the Thames Road Wetland site

Moon over Thames Road Wetland in the gathering gloom

9-16/11/10: Barnehurst garden update

9/11 - Wood Mouse in the compost heap

10/11 - Pine Ladybird (Exochomus quadripustulatus) in a gap between some stacked flower pots

12/11 - adult Common Frog active in the drizzle

14/11 - adult Common Frog active

15/11 - the current 'Fox in residence' (by which I mean my garden is part of its territory, though it doesn't have a den here) was around at dusk again, and this time came closer than ever - about 2 feet away from my feet as it followed its chosen route without bothering too much about my presence

The current 'Robin in residence' (maybe an incomer, maybe one of the three that were around a while ago) is also a lot bolder than the Robins of old here, and will often come within a foot and a half. If I'm working on the compost heap or repotting plants outside, it will quickly come and have a look then, if there aren't any titbits to be had it sensibly flies off to get about its business elsewhere.

16/11 - the first hard frost (although I admit I might have missed a previous one, being none too keen on getting up 'early')

Tuesday, 9 November 2010

9/11/10: Thames Road Wetland report to Bexley Natural Environment Focus Group

Note: Bexley Natural Environment Focus Group is an interface between Bexley London Borough Council and representatives of conservation organisations operating in the Borough. It is attended by various Councillors and Council Officers. The Group has not previously had a report on Thames Road Wetland (TRW) hence the amount of background detail in this particular report, which I am posting here as it may be of interest to a wider audience. In any event the site is in the hands of the Council, so in the interests of public accountability, here we are .....

But first, some 'Then and now' photos that were not part of the original report:

TRW February 2008. Photograph by, and reproduced with kind permission of, Steve Thoroughgood

TRW September 2008. Photograph by, and reproduced with kind permission of, Steve Thoroughgood

TRW October 2010. View closely matching that of September 2008.

to Bexley Natural Environment Focus Group

From: Chris Rose, Site Manager. 9/11/10.


Owned by Bexley Council. Managed under the auspices of (Thames21) Cray Riverkeeper Volunteers led by Ashe Hurst. I accepted the offer of the role of Site Manager in April 2010.

The site is in Crayford on the London/Kent border, by the lower reaches of the River Cray and was created in part mitigation for the Maiden Lane Roneo-Vickers development. It is an old field bounded by the River Cray to the west, Thames Rd to the north, the Dartford to Slade Green railway line to the east and an embankment with the North West Kent Sewerage pipes in it to the south. It was dug out to below the water table, so stays permanently flooded. The eastern end is transected by the canalised River Wansunt.

I have received no prior records from the developer/contractor ecologists as to species already present, water plants introduced, or what may have been trans-located here. Despite official requests, all I have been given is an outline plan showing ground-works and giving a list of the shrub species planted, so I have had to start from scratch. Steve Thoroughgood has kindly agreed to let me use, in presentations and reports, his pictures of the site from February and September 2008, relatively soon after the site was flooded and planted up, that I came across on Google Earth. The most recent GE imagery itself pre-dates the flooding.


The shrub plantings on parts of the Thames Road bank are largely of species not indigenous to the local area such as Guelder Rose and Wayfaring Tree, or are non-native in the case of Sambucus (tentatively) racemosa (which were supposed to be nigra). These have suffered badly from the drought earlier in the year, being on steeply-sloping gravelly ground.

There are a variety of aquatic plants, becoming dominated by Greater Reedmace, with some small patches of Phragmites australis reed bed (Bexley BAP). Ruderal plants of note are Slender Thistle, Annual Nettle and the recent non-native colonist Narrow-leaved Ragwort.

Other species here that are not especially frequent in this part of the Borough are Common Stork’s-bill, Vervain and White Melilot. The very infrequent plant Dittander occurs in large quantity on the Sewer Embankment and is spreading in the ‘bowl’. Star of Bethlehem was found this spring, but I have yet to determine whether it is the native sub-species (probably a garden escape from spoil). Brookweed (Samolus verlerandi) which I discovered in July is an important record as this may now be its only site in London.

Invertebrates will require specialist recording effort. Hairy Dragonfly, Migrant Hawker, large numbers of Blue-tailed and lesser numbers of Azure Blue Damselfly. Recent additions to the list include Roesel’s Bush Cricket, Long-winged Conehead and Wasp Spider.

Common Lizard – UK and London BAP, Grass Snake - UK and London BAP, Marsh Frogs and Common Newts are present.

Breeding birds – Moorhen (probably), Coot, Little Grebe, Reed Warbler (estimated 6-8 pairs)
Visitors – Grey Heron, Little Egret, various ducks including, most recently, a pair of Teal. Used by Black-headed Gulls from the Council Depot site in winter. Good numbers of Goldfinch are conspicuous at this time of year.

Two Water Vole (UK, London and Bexley BAP species) latrines recently found. Some Rabbit activity, but impact on vegetation small.


This spring contractors belatedly installed hibernacula on the Thames Rd bank without prior consultation with myself or Ashe Hurst, using good quality, cleaned, second-hand bricks (rubble from Maiden Lane might have been a ‘greener’ option). Some Star of Bethlehem will have been destroyed as a result, though they were warned it was there. Previous habitat work was disrupted and had to be restored. This south-facing bank has the most extreme temperature variations, so it is questionable whether hibernacula should have been sited here anyway.

Recent work has involved Reedmace-pulling to create and restore open shallow water. The aim is to retain overall vegetation diversity, increase the amount of Common Reed, submergents and non-reedy emergents such as Starwort and Water Mint, and to increase the variety of Odonata.

Careful ‘weeding’ has been done around the Brookweed to remove Teasel seedlings and some Creeping Buttercup. An adjacent area has had the soil level re-profiled, most of the Buttercup removed and bare ground created. Seed has been harvested from existing plants and scattered in this new area, particularly around the clumps of Rush that Brookweed appears to like growing at the foot of, in a bid to increase the number of plants and size of the area colonised. Further such work will be conducted when other operations in this area have been completed.

On the flat, compacted, gravelly north-east corner of the site, sinuous ditches and ‘dunes’ are being created to provide micro-habitat heterogeneityfor thermophilic and burrowing invertebrates.

To increase the Common Lizard population and enable it to colonise more of the site, corridors of appropriate cover will be created where little exists, and some areas of rank vegetation are being opened up. Cut vegetation has been heaped to create Grass Snake egg-laying sites.

Litter is a continuous, but fairly modest problem. There has been some unauthorised horse grazing, but this may actually help diversify the vegetation on some parts of the site. It is not clear if or how this process might be safely and legitimately facilitated and managed in future.

My intention is to involve members of specialist societies in order to properly record more difficult species groups, and to input management advice. They may also be a source of further volunteer labour. T21 has, however, recently handed down a significant increase in Health and Safety paperwork, which could constrain options. A formal site management plan is in preparation.

Any readers of this report who have interesting records from this site, who would like a guided tour or who would like to help with the management work are invited to contact me.

Occasional reports and photographs regarding the TRW site can be found here:

MY DETAILS: Chris Rose ......

Brought up locally. First class honours degree and an MSc in zoological science, Bristol University. Self-taught field botanist. Also have many years of experience of horticulture and cultivated plants. Recommenced recording all kinds of wildlife – particularly in the north and east of the Borough – in 2004, after a twenty year break.

Member of London Natural History Society, the South London Botanical Institute, Kent Botanical Recording Group and the Kent Reptile and Amphibian Group. In October 2010 helped set up a formal London Amphibian and Reptile Group and became both Reptile Officer and South East London Officer (covering the Boroughs of Bexley, Bromley, Croydon, Greenwich, Lambeth, Lewisham and Southwark). Joined the Bexley Natural Environment Focus Group in September 2010.

Saturday, 6 November 2010

6/11/10: Hyde Park - birds and Southern Oak Bush Cricket

A nice afternoon in Hyde Park with LNHS friends Miriam and her daughter Celeste.

Celeste is great at spotting 'bugs', and noticed this female Southern Oak Bush Cricket on the underside of one of the hundreds of London Plane leaves lying on the ground.

Good views were had of a foraging Green Woodpecker.

On the Serpentine were: two Mute Swans, two young Great Crested Grebes, Mallards, Tufted Ducks, Pochard, a male Shoveler, Canada Geese, Greylag Geese and a number of Black-headed Gulls.

Thursday, 4 November 2010

October and early November - Cray/TRW wildlife round-up

Observations made 7th, 14th, 20th, 28th October and 4th November 2010


A Common Fumitory and Wild Carrot were by a car park at the Thames Rd end of Howbury Lane, along with Spotted Medick.

At Thames Road Wetland, Reed Sweet Grass and Water Mint were noted. A Peacock butterfly was seen, also a Small Copper (from memory a new record for the site) and an inquisitive Migrant Hawker dragonfly. A 22-spot Ladybird was found. 6 Marsh Frogs and a couple of Common Lizards were spotted.

Whilst wading in the water to clear some areas of Greater Reedmace, groups of Lesser Water Boatmen were seen in open water (there are two families embracing these, Corixidae and Pleidae - I'm not sure which group these specimens fell into). Lesser Water Boatmen swim on their fronts, and Greater Water Boatmen species swim on their backs. A fresh Water Vole (UK, London and Bexley Biodiversity Action Plan priority species) latrine was found.

Fresh Water Vole Latrine at the margin of a patch of Reed Sweet Grass, on Thames Road wetland


Reed Canary Grass was noted by the Cray along Footpath 106. 2 Goldfinches were feeding on a Spear Thistle seed head. A Greater Spotted Woodpecker was calling from a very exposed position at the top of an exotic garden conifer. A Jay was seen flying across the river at the Barnes Cray Road end of the footpath.

A Greater Celandine was in flower by the culvert taking the River Wansunt under Maiden Lane.

There were 30 Mallard (including two black hybrids with white breasts) downstream of the Maiden Lane bridge over the Cray.

There were 7 or so Fennel seedlings around the adult plant on the eastern part of the Sewer Embankment by Thames Road Wetland. Sycamore leaves here were heavily infected with Tar Spot fungus. A flowering Black Nightshade was at the eastern end of the TRW site, by the trackway. There was some Self Heal in the pallet yard.

Sycamore at TRW, heavily infected with Tar Spot fungus

Black Nightshde in flower, TRW

On the flat section of the TRW, next to Thames Rd, were Parsley Piert, Buck's-horn Plantain, Shepherd's Purse, several Hemlock, Black Medick, two Sun Spurge, Fat Hen and Mugwort. A Geranium pyrenaicum, White Campion, Bristly Ox-tongue and Narrow-leaved Ragwort were in flower, along with a lot of Ribbed Melilot and White Melilot.

Narrow-leaved Ragwort in flower, TRW, beside Thames Road. Bristly Ox-tongue in front of it.

Ribbed Melilot (yellow flowers) and White Melilot flowering together on the TRW site by Thames Rd

Later a Jay was seen in a garden on Dartford Rd., and approximately 52 Starlings heading east over the railway line. A large Tomato plant with fruit was growing outside shops opposite the end of Heath Rd.


There was a Common Darter dragonfly at TRW, and another along By-way 105 as I headed for the Riverkeeper Volunteers yard. There was a Red Admiral on Footpath 106 by the yard. Heading back to the Wetland, there was a Fox on the north bank of the Cray.

On the 'lake' at the Wetland were a Coot and 4 Moorhens. Also a male and female Teal - a new species record for the site.


Thames Road Wetland - Great Tit, Blue Tit, 1 Chaffinch, a Robin and several Goldfinches along the Sewer Pipe Embankment. About 20 Black-headed Gulls on the 'lake'.

A Red Admiral was fluttering in the Willow (believed to have been poisoned during Giant Hogweed control operations) along By-way 105.

About 21 Canada Geese were flying west. A large Common Frog was in the Riverkeeper Volunteers yard.

Back at the Wetland a Darter landed on a dumped fridge on the Sewer Pipe Embankment and 8 Long-tailed Tits were at the east end of the site. 9 Ring-necked Parakeets flew over late in the afternoon.

A Darter dragonfly and a Dipteran fly share a perch on a dumped fridge at TRW

After working on the Wetland I went over to the south end of Dartford Marshes, but there were no ducks on the flooding fields yet. Around 92 Canada Geese flew up from the east side of the River Darent, and flew low over my head. OK they're not native, but there was still something majestic about the experience!


A flock of 23 Goldfinches were flitting about at the east end of Thames Road Wetland early this morning.

Reedmace removal operations revealed another Water Vole latrine,, though not as fresh as the one on 7/10.

I went out onto Dartford Marshes again, and in the by now very gloomy conditions, made out 10 (most likely) white-rumped Greylag Geese on one of the flooded fields.

October and early November Thames Road Wetland management work

TRW management activity 7th, 14th, 20th, 28th October and 4th November 2010

With my 'Site Manager' hat on, here's a round up of recent management work on the site, and the reasons for the various actions taken.

The main group activity on these dates was Greater Reedmace removal. The reasons for this were:

- to ensure the survival of other emergent plants, and to allow increases in some of them, such as Common Reed, and to prevent the water areas becoming too much of a Greater Reedmace monoculture
- to prevent encroachment onto the area occupied by the rare Brookweed
- to recover areas of shallow open water and muddy margins for (additional species of) Dragonflies and Damselflies
- to create more 'reed edge' microhabitat for foraging waterbirds
- to prevent the build up of excessive amounts of Reedmace litter in certain shallow areas, so as to slow/prevent succession to bog and then dry land, which would be more difficult to remedy later

Most of the work was concentrated on a shallow pool at the east end of the site, on the east side of the River Wansunt, which had been almost entirely taken over by Greater Reedmace.

The method used was pulling, as it was correctly surmised that this would bring up root and some of the rhizome carrying new shoots. (It works better where the water is deeper - i.e. the plants have had their feet in liquid mud all year, and less well in shallower areas where the water level has fallen below the soil surface for part of the year). It was felt that this would deliver better and longer term control than other options. Late last winter we had scythed off top growth, and horse grazing had had the same practical effect, but the Reedmace quickly caught up with untouched stands through regrowth from the base. The seed heads were breaking up at the time, so that the myriad seeds were getting in our eyes, noses and mouths. There is also a need to do this work when birds are not breeding. The RSPB's Reedbed Management handbook doesn't say anything much about Reedmace control, and Googling Reedmace control or management didn't turn up a great deal either. But searching 'Reedmace pulling' revealed the fact that a lot of other conservation groups around the country were going to be using the same technique at the same time of year, and this had increased my confidence in taking this approach.

Getting started - Cray Riverkeeper Volunteers Boss Ashe Hurst, Angelle and daughter Stephanie begin to make inroads into a 'wall' of Greater Reedmace

The cleared area gets larger

View from the sewer pipe embankment, looking towards Thames Rd. Cleared area visible left of centre. Removed Reedmace being piled up on the right.

Views from opposite directions showing the extent of the cleared area in mid November

We won't have got all the root out in this restored open water area, so there will be a need to go in again early next year to remove as much as possible of any regrowth.

Reedmace removal from around Common Reed (right centre) and Reed Sweet Grass (front right)

Reedmace removal from in and around a stand of Sedge at the north-west corner of the site

Another of my priorities was the creation of bare ground next to the current area of Brookweed, and weeding (mainly removing Creeping Buttercup and seedlings of Teasel) to favour the establishment of new plants of this species, which is very rare in London. Seed from the existing plants was scattered in this 'new' area in an initial attempt to increase the number of plants and double the 'footprint' of the colony. Brookweed appears to do best around the bases of these clumps of Rushes.

A further intiative is the digging of winding ditches (and creation of adjacent ridges from the spoil) in the flat, very open and sparsely vegetated north east corner of the site. The purpose of this is to create microhabitat heterogeneity and cover, especially for thermophilic (heat-loving) and burrowing invertebrates. It is also hoped that it will enable Common Lizards colonise more of the site. The work has been hard and slow-going because of the heavily compacted, extremely stony nature of the spoil that was dumped on this area.

If there are any readers out there who would like to get involved with hands-on management work here, please get in touch!