Lesnes Woods ‘garden grab’ – will Bexley uphold existing policy or signal further shift towards Boris-inspired ‘densification’ agenda?

‘Bexley Wildlife’ has been contacted by local residents opposing a plan to demolish numbers ‘5 and 6 Friars Walk to create access to a new development of 8 detached 2/3 storey houses (2×3 bed, 3x4bed, 3x5bed) with rear gardens backing to Abbey Wood, and new street, parking and landscaping at front”. It is being claimed by the ‘developer’ that the gardens are ‘wasted’ and of ‘no benefit’ to anyone, that there will be no adverse effect on protected or priority species either on or adjacent to the site, and that there will be no loss of trees, which looks dubious given the density of them indicated by aerial photographs. Approval would certainly be another unwelcome move regarding the future look and feel of our (for now) suburban Borough. 

Friar's Walk (right) would have

Friar’s Walk (right) for which an application has been submitted to Bexley Council to demolish two existing dwellings and build 8 new ones on what are currently gardens. 

An opponent says ‘We are a tiny woodland close adjacent to Lesnes Woods. We are set to lose many old native trees, plus Bats, slow worms, Stag beetles and other species as a result of a proposed housing development in 3 large gardens. Tawny owls and other birds have already gone since clearance started …… (we) do our best to support the indigenous wildlife and love the tranquility of this natural woodland environment.’

Unfortunately none of these species enjoy sufficient legal protection to stop this sort of ‘development’ from going ahead on their own account. However, Bexley’s Core Strategy (the Council’s policy ‘bible’) says, at Policy CS17, 4.8.10 :

 ‘The natural environment, and particularly our open spaces and waterways are also rich sources of biodiversity and archaeology. Back land areas in the borough include gardens and incidental open space. They should normally be excluded from development where developments results in harm to amenity and biodiversity. Further details in this respect will be set out in future policy documents, such as a development plan document that deals with detailed sites and policies. 

So in theory the Council has a policy against garden-grabbing and can legitimately turn the application down. The problem is that the Core Strategy is still the policy but is effectively a dead duck because the Council has decided to tear it up in favour of its much trumpeted ‘Growth Strategy’, at the heart of which (though it doesn’t say so very explicitly) is a target for a 20% growth in population. It laughably calls this a ‘Vision’. The reality is that it is kow-towing to Boris Johnson’s grand plan from when he was London Mayor. This involves what is politely termed ‘densification’ across the east side of London, which is essentially what this planning application is proposing. Whilst the ‘Growth strategy’ isn’t official policy yet, it will probably be touted as some kind of ‘agreed direction of travel’ in the meantime. Which position will win out in this case will therefore be a strong indication of what the future of our Borough is going to look like, irrespective of whether the Tories or Labour are in control as they both think all this ‘growth’ is unquestionably a ‘good thing’.  

The ‘developer’ states that residents in the Walk have collaborated on this scheme (though the wording is ambiguous as to exactly how many of them), and that it is supported by the National Planning Policy Framework (but then that is skewed massively in favour of building everywhere). Very disturbingly, in terms of setting a future precedent if the application is approved, the proponents are advancing the argument that: ‘These gardens are evidently hugely disproportionate to the houses and must be so by historical accident and it is impossible for these houses to either fully utilise and enjoy on indeed maintain these gardens; an impossible and unreasonable task to ask from them. Clearly these gardens, therefore, represent a very ineffective use of private land in reality being wasted and of no benefit to anyone let alone the owners. In effect, and in accordance with the emphasis on the dire need for housing (especially in London) and on the most sustainable use of resources, and given they are of no public benefit they ought to be developed, admittedly by a development of special character given their wonderful location. They cannot be used or enjoyed in full by the occupiers who want to understandably develop them as they are enormous and a financial burden to them.’

The applicant further claims that ‘This proposal, by utilizing effectively currently huge neglected and underused private areas of no public benefit will not only make efficient use of this land – a key primary planning sustainability objective’. It is not obvious that this squares with providing an extra 21 parking spaces over what already exists. Nor does the size, location and likely sale price of the proposed dwellings suggest that the ‘development’ will do much to help those most in housing need.

We suggest that all ‘BW’ followers worried about the same thing happening on their patch start opening their gardens to the public with immediate effect ….. !

Posted in development threat, Environment, Lesnes Abbey Woods | Tagged , , , , , , , | 1 Comment


This revised and updated guide to the 29 species of butterfly known to be resident in, or that have recently visited, the London Borough of Bexley, includes details of their conservation status, a guide to the kinds of habitats in which they are most likely to be found, named locations at which the less frequent ones may be seen and photographs of selected species.

Since the 4th edition published in May 2016, White Admiral has been unequivocally confirmed as a denizen of Bexley, with one of the sightings suggesting that an ‘unverified’ record from 2003 was almost certainly correct. A fourth Marbled White has been seen and photographed, but the hoped for larger influx and an indication of the commencement of a sustained colonisation has yet to be detected. There are new site records for Brown Argus, Green Hairstreak and Small Heath.  Notably, the 2016 season was an above-average one for  numbers of the Clouded Yellow in the Borough, with 12 seen across five different locations.

Compiled by Chris Rose with additional Bexley records and photographs from John Archer, Steve Carter, Joe Johnson, Mike Robinson, Purnendu Roy, Ian Stewart, Karen Sutton, Ralph Todd and Donna Zimmer, the document comprises an illustrated cover and 15 pages of text and images. It can be read online below, or downloaded as a pdf file.

Download the PDF file .

Posted in Bexley, Butterflies, Recording | Tagged , , , , , , , , , , , , , , , | Leave a comment


This updated guide to the 19 species of Dragonflies and Damselflies of the London Borough of Bexley, compiled by Chris Rose with additional records and photographs from Ralph Todd, Ian Stewart, Karen Sutton, Martin Petchey and Wren Rose, provides information on and photographs of the first observations of the Willow Emerald Damselfly in Bexley – which arrived in the Borough during 2016 – as well as other key sightings which have led to additions to the species lists for Crossness (Erith Marshes), Footscray Meadows and Lamorbey lake.     

Comprising an illustrated cover and 12 pages of text and photographs, it can be read online below, or downloaded as a pdf file.


Download the PDF file .

Posted in Bexley, Crossness, Crossness Nature Reserve, Danson Park, Dragonflies and Damselflies, Recording, River Cray, River Shuttle, Thames Road Wetland | Tagged , , , , , , , , , , , , , , | 1 Comment


The guide to the mammals of Bexley, compiled by Chris Rose with contributions from a number of local wildlife observers,  has been significantly updated to include a number of new Hedgehog records, additional information about Harvest Mice in the Borough, details of the credible sightings of Reeves’ Muntjac Deer in the Sidcup area, links to further reference material and more mammal photographs taken in the area. 

There are 30 species of ‘wild’ mammal (including humans!) considered resident in the Borough. Details of others that may be present or that are known to have become extinct during the 20th century, are also provided.  

Comprising an illustrated cover and 26 pages of text, it can be read online below, or downloaded as a pdf file.

Download the PDF file .

Posted in Bexley, Extinction, Harvest Mouse, Hedgehog, Lesnes Abbey Woods, London Wildlife Trust, Mammals, Recording, Weasel | Tagged , , , , , | 2 Comments

Friends of the Shuttle events Jan-March 2017

Advance notice of Friends of the Shuttle events on the River Shuttle, at Danson Park, and in Danson Park Old English Garden (which the group helps maintain).  The River Shuttle meeting time is 10.30, that for the OEG is 10.00. Shuttle meeting points will depend on an assessment nearer the relevant dates as to which stretches need attention. Meet at the garden for OEG work. Ffi: “Friends of the Shuttle” <friends.of.the.shuttle@gmail.com>  See also: 




12th January River Shuttle (location tbc)




19th January OEG TB
Saturday 21st January OEG TB/JS
26th January River Shuttle (location tbc)




2nd February OEG TB
9th February River Shuttle (location tbc)




16th February OEG TB
Saturday 18th February OEG JS/TB
23rd February River Shuttle (location tbc)




2nd March OEG TB
9th March River Shuttle (location tbc)




16th March OEG TB
Saturday 18th March OEG TB/JS
23rd March River Shuttle (location tbc)




30th March OEG TB
Posted in Danson Park, Friends of the Shuttle, River Shuttle, Rivers, Volunteering | Tagged , , , , | Leave a comment

Bexley RSPB members see Cattle Egret on Rainham visit

Having the Rainham RSPB reserve just over the water from Crayford Marshes increases the prospects of rarities turning up on our side of the river. Bexley RSPB members visiting on December 17th were delighted they got to see a Cattle Egret, as well as a good number of Pintail, despite the foggy conditions which otherwise limited their sightings.

Download the PDF file .

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Bexley butterfly highlights of 2016

A round-up of key butterfly observations in the London Borough of Bexley during 2016

Principal contributors – Steve Carter, Joe Johnson, Mike Robinson, Chris Rose and Purnendu Roy.

Summary: As envisaged in the 2015 report, White Admiral was confirmed as a Bexley resident at two woodland locations during 2016, taking the Borough’s total of butterfly species to 29. Clouded Yellow was more numerous than usual with sightings of 12 individuals across 3 lower Cray catchment locations, Crossness and East Wickham Open Space. Marbled White was found at a new site, but there were no definitive signs that it was managing to establish a permanent foothold in Bexley this year. Brown Argus was seen at three new locations, Small Heath at two and Green Hairstreak at one. Small Tortoiseshell remained low in numbers and was mainly spotted at the usual relative hotspots out on the marshes. There were few Painted Lady reports and Small Copper was worryingly thin on the ground, reflecting what appears to be a national decline. On May 1st Joe Johnson launched the Bexley Butterfly and Moth Facebook page – https://www.facebook.com/BexleyButterflyandMothGroup/ – and at 15/12/16 this had 53 likes and 50 followers.

White Admiral (Limenitis camilla).  Tantalising records from last year strongly suggested that this species occurred in Bexley, but observers had not been sure that they had seen it within the Borough’s boundary. It is very uncommon in London, with reports from only 3 sites to as recently as 2015.

Steve Carter saw a White Admiral in Joydens Wood on July 18th 2016 and reported it on the ‘Bexley Wildlife’ Facebook page. When quizzed he gave an approximate grid reference which appeared to put him on the main path heading south-east from the Keeper’s Cottage, and was within Bexley. Armed with this information, Bexley Butterfly and Moth Group’s Joe Johnson, Mike Robinson and Chris Rose went in search of further sightings in this area on July 23rd. In the meantime, Mike had photographed one at the Parsonage Lane end of the wood on July 21st, believing that this too was inside the Bexley boundary.

The weather was somewhat changeable, with periods of no sun, then butterflies taking to the air as soon as it came out again. But we were in luck, seeing a White Admiral in the first area of young coppice by the side of the aforementioned path that we came to, well within the Bexley boundary.

White Admiral, Joydens Wood, 21st July 2016. (Photo: Mike Robinson)

White Admiral, Joydens Wood, 21st July 2016. (Photo: Mike Robinson)

During the late afternoon of the 23rd, Chris Rose (now solo) saw another along the ride that continues beyond the end of Parsonage Lane, which is pretty much on the Bexley/Kent border. He then found two more White Admirals in clearings in Gatton’s Plantation, which is wholly within Bexley. These latter sightings indicate that the 2003 record of the species made at the Plantation by top botanist Mark Spencer, but which the London biodiversity records centre (GiGL) has classed as ‘unverified’ was probably, in fact, correct.   

Silver-washed Fritillary (Argynnis paphia). This species has only been recorded from a handful of sites in London, and was confirmed as resident in Bexley in 2015. On July 23rd 2016 Joe Johnson, Mike Robinson and Chris Rose visited Joydens Wood and saw a few of these insects in coppiced areas along the main path heading south-east from the Keeper’s Cottage, within the Bexley boundary. Chris Rose also saw one later that day along the ride that continues beyond the end of Parsonage Lane, which is essentially on the Bexley/Kent border.  

Silver-washed Fritillary on Hogweed in the Bexley part of Joydens Wood, 23rd July 2016. (Photo: Mike Robinson)

Silver-washed Fritillary on Hogweed in the Bexley part of Joydens Wood, 23rd July 2016. (Photo: Mike Robinson)

Mike also discovered the species in Gatton’s Plantation, which is next to Joydens Wood, and wholly within Bexley, on August 16th.

Image may contain: plant, flower, outdoor and nature

A rather worn Silver-washed Fritillary pictured at Gatton’s Plantation 16th August 2016.  (Photo: Mike Robinson)

Clouded Yellow (Colias crocea). This migrant species is only very occasionally seen in Bexley, so twelve in one year is somewhat exceptional. As usual, sightings were predominantly from our ‘coastal’ areas. Purnendu Roy saw and photographed one at East Wickham Open Space on August 11th. Mike Robinson saw one at Crossness on August 17th and two there on the 24th. Steve Carter then reported seeing six at Crayford Marshes on August 26th. Chris Rose found one on the derelict former Electrobase industrial site in Crayford town centre, next to Roman Way, on September 11th  and saw another on September 14th Sept at the south end of By-way105 by the River Cray near Maiden Lane. What was at the time thought to have been a distant Jersey Tiger at Thames Road Wetland, may in retrospect have also been a Clouded Yellow, given the understanding of apparent colour and flight characteristics developed out of later sightings. 

Image may contain: plant, flower, nature and outdoor

Clouded Yellow at East Wickham Open Space, 11th August 2016 (Photo: Purnendu Roy)

Marbled White (Melanargia galathea). With two sightings in Bexley in 2015, records from both Bromley and Greenwich between 2012 and 2015, Ladywell Cemetery in Lewisham in 2015 and LNHS 2014 butterfly count data for London giving the highest Marbled White figures since reliable information for the species first became available in 1997, there were hopes that the species might be on the verge of ‘doing a Ringlet’ and begin to spread quickly across the Borough. There was only one confirmed record, however, with Mike Robinson getting a photo of a single specimen at Upper College Farm, a new site record, on 17th July 2016. Shaun Marriott, Site Manager at London Wildlife Trust’s Braeburn Park reserve in Crayford said in July that he had been told that the species had been seen there, but we have not been able to verify this to date. 

Image may contain: plant, flower, nature and outdoor

Marbled White at Upper College Farm, July 17th 2016. (Photo: Mike Robinson)

Ringlet (Aphantopus hyperantus). The rise of the Ringlet in Bexley appears to have begun around 2011/2012. It has since colonised the many suitable sites that have been studied. The only noteworthy new record was of 32 individuals seen flying in a small part of Braeburn Park on July 10th by Chris Rose.

Small Heath (Coenonympha pamphilus). This small, pale butterfly is a Biodiversity Action Plan species for research due to an apparent decline, including due to loss of habitat. Mike Robinson confirmed and photographed it at Upper College Farm on May 26th, when it transpired that Ian Stewart had first seen it there about 3 years ago but had not submitted the record to GiGL. 


Small Heath at Upper College Farm on 26th May 2016.  (Photo: Mike Robinson)

Chris Rose saw and netted a single specimen on a dry grassy bank at Thames Road Wetland on June 6th, and was able to make doubly sure of the ID before release. He also saw a few flying a Braeburn Park on July 10th. These were both new site records. The species has previously been recorded over on Crayford Marshes, so the Wetland insect may well have been a lone wanderer or wind-blown individual. According to GiGL data it has also been seen over the railway line from Braeburn at Crayford Rough, but not since 2007. Mike Robinson actively looked for the species at East Wickham Open Space on June 6th, but couldn’t find any.

Small Tortoiseshell (Aglais urticae). Numbers of this once frequent species remain severely depressed, with records continuing to come mainly from locations nearer to the Thames. Mike Robinson has submitted the most sightings. He saw his first for the year on 28th January in the gardens at Hall Place. The most he saw on any one day during 2016 was seven on 19th April at Crossness (this compares to his highest figure for 2015 of thirteen on 3rd July, again at Crossness). Others were beside a Public Footpath off Church Manorway, beside the Thames Path in both the Belvedere and Erith areas, at Crayford Marshes, Crayford Rough, East Wickham Open Space, the Hall Place flood overspill area, Hollyhill Open Space, Lesnes Abbey park/Woods and beside the Upper Bedon Stream (Streamway). He has commented that he probably saw around half the number of individuals he witnessed in 2015. Steve Carter saw one at Crossness 17th August and two on Crayford Marshes on 26th August. Amongst others, Chris Rose saw one each on 10th July and 16th August at Braeburn Park.

Painted Lady (Vanessa cardui). Another poor year for this migrant from Africa. On 5th June Chris Rose saw one in a garden part way down Midhurst Hill, Bexleyheath, feeding on Red Valerian, and a second on Bramble flowers at Parish Wood Park.  Also on 5th June Mike Robinson saw two at Lesnes Abbey park/Woods, plus one in the East Wickham Open Space on 6th June, one on 26th June beside a public footpath off Church Manorway and one on Crayford Marshes on the same day. In general terms Mike reckoned he probably saw less than half as many as he had done in 2015. Other records included Thames Road Wetland on 29th July (Chris Rose), 10th August and 12th September at Crossness Nature Reserve (Steve Carter), 14th August at Lesnes Abbey (Mike Robinson), 16th August at Braeburn Park and a pristine individual on 29th August at Grasmere Road allotment site (Chris Rose), and Crayford Marshes on 26th August (Steve Carter) – all of which were singletons.

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Painted Lady at Lesnes Abbey, 14th August 2016. (Photo: Mike Robinson)

Green Hairstreak (Callophrys rubi).

Two sightings of the species by Chris Rose at Thames Road Wetland on the 20th and 21st of May constituted a new site record, some distance from other known locations in the Borough. 

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Green Hairstreak, Erith Southern Marsh. May 13th 2016. (Photo: Mike Robinson)

Small Copper (Lycaena phlaeas). Very few reported sightings, all singles. These were 4th June at Hollyhill (Mike Robinson),  Braeburn Park on 10th July (Peter Beckenham), one beside the Upper Bedon Stream (Streamway) on 14th July (Mike Robinson), in a glade at Martens Grove on 11th September and another at Grasmere Road allotment site on 13th September (Chris Rose).  Finally, one was seen and photographed by Mike Robinson at the closed Thamesview Golf Course on 15th September, who has commented that this species was “Massively down on 2015”.

Image may contain: flower, plant, nature and outdoor

Small Copper, Thamesview Golf Course. 15th September 2016.  (Photo: Mike Robinson)

Brown Argus (Aricia agestis).  There were new site records from the small area of land between Gascoyne Drive and Thames Road (adjacent to Perry Street Farm) where there was perhaps only one individual, at Grasmere Road Allotment site and at Thames Road Wetland, all discovered by Chris Rose.

This report has been sent to the London Natural History Society butterfly recorder for its 2017 journal, which will contain the 2016 transect count and species status reports and be published in early 2018.

Report compiled by Chris Rose.

Posted in Bexley, Butterflies, Crayford, Crayford Marshes, Crayford Rough, Crossness, Crossness Nature Reserve, East Wickham Open Space, Erith Marshes, Hall Place, Hollyhill open space, Invertebrates, Joydens Wood, Lesnes Abbey Woods, London Wildlife Trust, Martens Grove, Parish Wood Park, Recording, River Cray, Thames Road Wetland, Uncategorized | Tagged , , , , , , , , , , , , , | Leave a comment

Bexley RSPB Foots Cray Meadows 6th December bird walk – report

Ralph and Brenda Todd report on the 6th December Bexley RSPB bird walk at Foots Cray Meadows, which attracted several members new to the group’s outdoor meetings. 28 species were seen including Little Egret, Kingfisher and Gadwall. 

Download the PDF file .

Posted in Bird watching, Foots Cray Meadows, River Cray, RSPB, Uncategorized | Tagged , , , , , , , , | Leave a comment

London Assembly green spaces investigation – comments sought, London Green Spaces Friends Group Network submission

The London Green Spaces Friends Groups Network


The Future of London’s Green Spaces:

London Assembly Investigation / Inquiry now underway. Evidence and recommendations requested.

Our much-loved parks and green spaces – around 3,000 throughout London – are recognised by all to be essential public resources providing an unparalleled range of vital services and facilities for all sections of our communities, and for nature. But their future is under threat due to Government cuts to local public services. This serious underfunding crisis needs to be addressed and reversed immediately.

The London Assembly has agreed to hold a formal Investigation /Inquiry into this crisis engulfing London’s public parks and green spaces, and what needs to be done. Full details here.


All those who are concerned on this issue and wish to respond with evidence on the state of London’s green spaces and their views on what should be done to protect, enhance and improve them for current and future generations are urged to respond – initial deadline Friday 9th December (but responses will be accepted after that date).

Our initial draft response, which others are welcome to endorse or adapt, is set out in full below. E-mail submissions should be made to:


In summary, the Friends group Network is saying that our public green spaces need:

– statutory recognition as a statutory service, with all public green spaces expected to be managed to Green Flag Award standard

– adequate public funding (eg from general taxation or majorinfrastructure budgets)

– effective protection by all tiers of Government

Dave Morris – for the London Green Spaces Friends Groups Network


Download the PDF file .


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Harvest Mice – first images of this London rarity in Bexley

Nests of of Harvest Mice (Micronomys minutus) , the UK’s smallest rodent, were first found at Thames Road Wetland in 2014, when 7 were discovered in the course of vegetation management work. None were located in 2015, but another three were come across in 2016. Both still and video images have now been obtained of this elusive species, which has only been recorded in 5 other London Boroughs over the last 20 years. Found in England and Wales, it is now a Biodiversity Action Plan priority species on account of a 71% decline up to the last review in 2007.

A cunning plan to ‘see’ the Mice themselves

Inspired by an article in ‘BBC Wildlife Magazine’ about the work of a PhD student studying Harvest Mice – see 


TRW Site Manager Chris Rose, who operates under the umbrella of the Thames21 waterways restoration charity, installed a series of feeding tubes made of plastic drinks bottles in 2016, regularly replenishing them with bird seed, in order to habituate the animals to using known filmable fixtures in their environment. The tubes were situated in such a way as to make it difficult for anything larger and heavier than a Harvest Mouse to gain access. 

Mark2 'safety' design of Harvets Mousefeeding tube, baited with birdssed. 'Escape hatch' at rraer end and raised falp to sto the wind shaking out the seed. (Photo: Chris Rose)

Mark2 ‘safety’ design of Harvest Mouse feeding tube, baited with birdseed. ‘Escape hatch’ at rear in case the bottle comes loose and tips up. A raised flap forward of this  stops the wind shaking out the seed. Fabric sticking plaster taped into the neck aids grip and exit at the mouth end. (Photo: Chris Rose)

At the end of October two Little Acorn camera traps, paid for by Thames21 from grant funding, were set up by Chris, Joanna Barton (Assistant River Cray Project Officer for T21), plus volunteers Ray Hudson who supplied the DIY skills, and Wren Rose who has done the work since of trawling through the camera SD cards and extracting the best imagery.

We have had some technical issues, the first of which is a basic limitation of the devices, in that they are designed to capture big animals at some distance, not tiny Mice a couple of feet away. The second is that we set them up to take an initial still and then trip to video. The video should continue for some time longer than the few seconds per clip we have got to date. If anyone is familiar with this make of camera trap and can offer advice on fixing this problem, please get in touch. Meantime we have set them to video only.

Harvest Mice take the bait and appear on-screen

The birdseed in the various feeding tubes has repeatedly been reduced to husks, and Harvest Mice have now appeared in front of the cameras. The following are some of the best images obtained so far. They are undoubtedly the only ones ever taken to date of Harvest Mice in Bexley, possibly the only ones of the animal itself in London – certainly in the last few years – and may be the only film of wild Harvest Mice in the capital.

Harvest Mouse in corner of filming 'stage'. Taken by camera trap 27th October, 2016.

Harvest Mouse in corner of filming ‘stage’. Taken by camera trap 27th October, 2016. 

Harvest Mouse climbing up to feeding bottle at dusk on 17th November 2016. Camera trap in night-time mode.

Harvest Mouse climbing up to feeding bottle at dusk on 17th November 2016. Camera trap in night-time mode.

Video clips of Thames Road Wetland Harvest Mice (large files, will take some time to download to your computer for viewing):



The status of Harvest Mice in London

Few records exist, and those that do are largely of nests or of a dead animal. According to Greenspace Information for Greater London (GiGL), the London biodiversity records centre, Harvest Mice have only been recorded from 6 London Boroughs since 1996 – Bexley once before, Bromley twice (Churchill Plantation, Hang Grove Farm), Barking and Dagenham twice, Barnet twice, Havering four times and Redbridge five.  Unsurprisingly, with the exception of Barking and Dagenham, these are all on the periphery of London. Prior to the TRW nests of 2014 there had been no (reported) London records since 2010.

Where did the TRW animals come from, and when?

Aerial photographs from the late 1930s and during the war suggest that TRW did not provide suitable habitat for Harvest Mice at that time, and an early 1980s photo shows an overgrazed field similarly devoid of the necessary vegetation structure. Although it was better by the mid 2000s, the extensive work to create the wetland in late 2007 would probably have resulted in the loss of any Harvest Mice that might have been present at that time.  

Colonisation (or recolonisation) could have come from one of three possible sources: 

i) From the south along the railway line to Dartford.

ii) From a separate population on Stanham Farm, including the River Cray margins,  to the south of TRW

iii) Over the Thames Road railway bridge from Crayford Marshes. The previous Bexley record was of either a single nest or a single animal (it is not stated which) in the reedbed at the Erith saltings by the Yacht Club, made in 2007. There could still be a population spread across Crayford Marshes,  and this may have at one time been continuous with any animals that survived south of the road. The road itself has, however, long been of a width that research says Harvest Mice would not cross at ground level.  

A fourth though probably unlikely alternative is that a female was dropped alive by a predatory bird.

Six of the seven nests found in 2014 were spread along a linear feature over quite a distance, with a seventh some way away on the other side of a waterbody. This suggests the species may have already been present at TRW for a year or two, although the nature of the vegetation management up to that point suggests that if nests had been present in previous years, at least one or two would have been found.  

Habitat and behaviour

The name Harvest Mouse is suggestive of an animal that is confined to or very strongly associated with arable farmland, but in practice wetland with reedbed is an important habitat type for the species. At TRW occupancy appears to be greatest in an area over shallow water with a mix of dense Sedge bed, a moderate amount of Common Reed and adjoining grasses on a bund by a ditch. Reedmace on its own, which is a major component of the site’s vegetation, does not appear suitable for nest-building.

We have been somewhat surprised by the extent to which the Harvest Mice have been active in daylight. This may be  to do with fattening up for winter (though they do not hibernate) or possibly avoiding competition/interaction with Wood Mice and Rats, though we do have one poor quality night-time photo where a Harvest Mouse is climbing up to a feeding bottle which appears to have a Wood Mouse already in it.  

Is the population growing or declining?

We cannot determine this on the basis of current information. Small mammal numbers can fluctuate greatly for a variety of reasons. Autumn is a good time to try and get film because numbers of animals will be at their highest post-breeding, and before winter mortality.

Predation pressure will largely be coming from Foxes, and possibly Weasel (one was ‘captured’ by one of the cameras recently, establishing a new site record). A very occasional domestic Cat is seen, though none in the main Harvest Mouse area. Whilst birds of prey frequently overfly the site, the main prey of the species seen are other birds.

Other rodents

The cameras have also recorded Wood Mouse. The following pair of images shows the difference between Wood Mouse (left) and Harvest Mouse (right) , particularly in the size of the ears:

Wood Mouse (left) and Harvest Mouse (right). (Comparative image created by Wren Rose)

Wood Mouse (left) and Harvest Mouse (right). (Comparative image created by Wren Rose)

The local Brown Rats have also proven themselves rather more acrobatic than expected:

Brown Rat examining Harvest Mouse feeding bottle at Thames Road Wetland.

Brown Rat examining Harvest Mouse feeding bottle at Thames Road Wetland.

Further study and conservation

It is clearly important to try and maintain and build numbers of the mice at this location, in which there is an area of relatively low wildlife interest that could be made more suitable for them by using ‘spare’ shrub suckers from elsewhere on the  site to create a low grass-edged hedgerow.

The nature of the site would make it a good one for any student interested in pursuing a more detailed project about Harvest Mice to work on. It would also be invaluable to establish the distribution of the species across the wider local landscape. Please contact Chris Rose on chrisrose@gn.apc.org  if you are interested.

Thus far the Mice, and several other rarities at the wetland, will have benefitted from the fact that although the whole site – which falls within a Site of Metropolitan Importance for Nature Conservation – is open to the public, the location and layout of it has meant that in practice very few people wander round unaccompanied and therefore the amount of disturbance and random trampling is minimal, and there are no dogs being allowed to run amok. This state of affairs needs to be maintained. Guided tours are run for time to time for those who are interested.

This first Harvest Mouse nest was found at Thames Road Wetland in 2014 (Photo: Chris Rose)

This first Harvest Mouse nest was found at Thames Road Wetland in 2014 (Photo: Chris Rose)

Chris Rose. Thames Road Wetland,  Thames21 (volunteer) Site Manager. 

Posted in Bexley, Biodiversity Action Plan, Harvest Mouse, Mammals, Raptors, Recording, Reedbeds, SINC, Thames Road Wetland, Thames21 | Tagged , , , , , , , , , | 2 Comments