Lee Brady's Recording Blog

Translocating Reptiles Before Planning Permission?

Conversations with several folk who are engaged with the Kent planning system have revealed a worrying trend - the translocation of reptiles away from proposed development sites before planning permission has been granted (or in some cases even applied for).

A recent news story from Sussex suggests that this is not just a Kent problem. The Mid Sussex Times reports that:

"People living near ['the Dip'] in Hawth Valley say its several acres of land and a deep pond are a vital breeding area for protected species.

But planner Alan Edgar, who speaks for the land owner and developer John Rigden, said the response from local residents was 'a typical NIMBY reaction'. "

So local people who are concerned about the impacts of development on their local biodiversity are nothing more than 'NIMBYs' eh? Way to go with the public relations Mr. Edgar!

"My client has cleared the site but he has done it in a very responsible and ecologically concerned way. He has done nothing illegal.

He said slow-worms and even rats had been caught properly and moved.

Mr Edgar said he would be drawing up plans for 16 houses – to include some affordable homes – and an ecology park would be proposed at the bottom of the site."

If I understand the news item correctly, the developer will be drawing up plans for 17 houses after the slow-worms have already been removed from the development site?

According to guidelines published by Natural England (download):

"Reptiles should not normally be removed from development sites before the planning decision is made."

Mr. Edgar is quite right that the removal of widespread reptiles from a site before planning permission has been granted is not illegal (providing the animals have been released into an area where they will survive). However, if translocation has been undertaken before planning permission has been granted, I would question whether the work has been undertaken in a 'very responsible and ecologically concerned way'.

I guess if the biodiversity interest of a site is removed, then there is one less thing for the local planning officer to consider when deciding on whether planning permission should be granted. Let's face it, the planning officer can't really refuse permission due to biodiversity interest, if the biodiversity interest has already been removed!

I wonder how these actions square with the Government issued PPS9 and whether IEEM advise ecological consultants that they should not engage in such practices?

Edit for typo.

Wall Lizards in Britain

For those of you interested in this year's discovery of wall lizards at Folkestone, you may be interested to visit a web site dedicated to recording other occurrences of these colourful lizards.

The site is maintained by Steve Langham on behalf of the Surrey Amphibian and Reptile Group. Regarding speculation as to whether the lizard is native:

"There has been some discussion as to whether the Wall lizard is a species native to the UK, as it is in the Channel Islands. Although it cannot be ruled out with all certainty, there is no scientific evidence to support such a claim.

One argument that is frequently cited is an analogy with the Pool frog, which was believed to be an alien species, yet has recently been accepted as a native. This acceptance of the native status of the Pool frog was based upon scientific assessment of substantial evidence (including ancient records, museum specimens, zooarchaeological remains & DNA analysis), rather than mere speculation, as is the case with the Wall lizard."

There's lots of other useful information available. Visit the site to read more and perhaps to add your own observations. I must remember to add details of a colony that used to be located near Canterbury. I wonder if Steve would also be interested in putting something together on green lizards?!

Announcement - ARG UK SE Regional Conference 2007

Come and celebrate the 20th birthdays of both Sussex and Surrey Amphibian and Reptile Groups!

Don't miss out on the event of the year! This will be a great day, at a prestigious venue, with something to interest every one interested in amphibians and reptiles. Keynote speaker is Mark Amey, who, amongst many other remarkable achievements, has been working on 'Life in Cold Blood' with David Attenborough - due to be broadcast in Spring 2008.

Just £12.00 including refreshments and lunch (£5.00 unwaged).

Download a printable copy of the programme.

Download a flyer with booking information.

Rick Anstis

Secretary Surrey ARG

Review of BBC Wildlife Article

A few weeks ago I was interviewed by Mr. James Fair (a journalist working for BBC Wildlife) who was interested in publishing a story on the Species Action Plan (SAP) targets that were announced for great crested newt earlier this year. Following a lengthy interview Mr. Fair wrote a news story entitled 'In the Eye of a Storm' that was published in the October 2007 edition of the magazine. The article attempts to inject controversy into what is really quite a dull story.

Does it succeed in generating a storm, or are we simply left with little more than a muddy puddle. Read on to find out!

The tag-line for the story gets off to a bad start:

"The great crested newt is a rare British amphibian protected under European legislation and theoretically the subject of focussed conservation efforts. So why can no one agree on how many are out there?"

'Theoretically' the subject of focussed conservation efforts? Where is Mr. Fair's evidence that current conservation efforts are unfocussed? He certainly does not address this in his article. In fact, I would argue that conservation efforts are becoming increasingly more focussed. Mr. Fair also suggests that no one can agree on how many newts there are in the country. No one? Reading Mr. Fair's article it would appear that the only person he could find who doesn't agree is Tom Langton. Are we supposed to infer that Tom is a no one?!

The main body of the article continues:

"The scientists say that the species is not as rare as once thought..."

Who are the scientists who say this? They remain rather elusive in Mr. Fair's article. Has anybody actually said this?

I consider that in some areas the species is relatively widespread, but even in these 'hotspots' gcn can be highly sensitive to environmental change. The species appears to be dependent on areas of relatively high pond density. Where conditions change and there is a decrease in the number of suitable breeding ponds, gcn populations often collapse.

In Kent, the BRANCH project has made predictions of how climate change may result in significant declines in species such as the great crested newt. So rather than attempting to define gcn in terms of 'rarity', it may be more accurate to state that 'the great crested newt is far more threatened than even the early conservationists could have believed...'. Just a thought.

"...but their figures are speculative and disputed."

What scientific data isn't speculative and disputed!? Good science involves the testing of a null hypothesis. Scientific experiments don't attempt to prove that an idea is correct, they try and prove that it is wrong. If ideas were never challenged there would be little scientific progress. It is fantastic that somebody disputes the reported figures. What we now need is for other herpetofauna workers to review this subject and publish their own occupancy data.

I guarantee that the currently quoted figures for the number of gcn ponds in the country will not be exactly correct. But, you know what? At the present time it doesn't matter if we are a few thousands or even tens of thousands out. What we really need to know is how accurate are our current estimates and how can we refine our techniques to improve the accuracy of our future predictions? Hopefully, publication of the new SAP targets will increase debate and lead to increased reporting of survey work.

"The Herpetological Conservation Trust (HCT) now estimates that there are 100,000 ponds in Britain that have great crested newts, a figure more than five times that in the previous SAP, which said there were 18,000 breeding ponds."

A cheeky sleight of hand here by Mr. Fair. On the one hand we have 100,000 ponds that have gcn. On the other we have 18,000 breeding ponds. As I have previously shown there is actually quite a difference between occupying a pond and breeding within it. Taking gcn occupancy data for Kent as a reference, out of those 100,000 ponds perhaps 'only' 61,000 may be used for breeding. Of course, the relationship between occupancy and breeding will vary across the country particularly in areas with different pond densities. But even so, it's not quite the five-fold increase that Mr. Fair suggests.

"Tony Gent ... says that the new figure is based partly ..."

Emphasis mine.

"... on research carried out by Dr Lee Brady ..."

Indeed, the new figure was partly based on research undertaken by myself and other Kent based colleagues (including KRAG volunteers). This research produced the occupancy data that I have generated using habitat suitability indices (HSI). As Jim Foster later points out, it was also influenced by data from several other areas, including extensive surveys in Norfolk, Suffolk, Herefordshire (hi Will!) and Flintshire.

Given that there are believed to be about 400,000 ponds in Britain, if the new figure was wholly based on Kent occupancy data we would be looking at 176,000 gcn ponds across the country (400,000 x 44%)! Considering that there are apparently 25,000 ponds in Sheffield gardens alone, the Pond Conservation estimate of 400,000 ponds in the country may already be out of date.

"'This is a very rough figure', he said. 'Between 50,000 and 100,000 is likely to be the best guess.'"

Tony is suggesting that on average, gcn are likely to occupy between 12.5% and 25% of the country's ponds. Clearly in some areas (such as Kent and Cheshire), occupancy levels will be much higher. Elsewhere, gcn may be completely absent (e.g. Cornwall).

Apparently, Tom Langton (who is described as a government advisor on newt issues - does that also make me a government advisor I wonder?) believes that the 100,000 figure is too high. Fair enough, it might well be. Tom is then quoted as saying:

"Published research suggests there are no more than 25,000 occupied ponds"

I don't see any reference for this 'published research'. But let's be clear here. Until the recent boon in ecological consultants, extensive amphibian surveys were rather limited. Early survey work often suffered from a lack of effort. The detection of gcn in ponds can be hampered by muddy water, lots of weed and limited time. Under these conditions, gcn tend to only be recorded in the ponds where they are easiest to find. I suggest that early estimates of gcn pond occupancy failed to adequately address gcn detectability. Survey techniques are increasingly becoming more sophisticated so that problems with the detectability of a species can be minimised (e.g. distance sampling). For gcn, detection rates at ponds are increased by using multiple survey techniques across several visits. Sadly, estimating the number of gcn that occupy terrestrial habitat is still a very difficult prospect.

So am I suggesting that Tom's comments are wrong? No, not at all. However, the science has moved on.

"These differing views on the status of the great crested newt may stem from Brady originally claiming that there are 18,000 occupied ponds in Kent alone."

No, the differing views are based on individual interpretations of different datasets. As far as I remember, Tom wasn't on the gcn SAP steering group and didn't contribute to the discussion of the most recently available dataset.

Have I claimed there are 18,000 occupied ponds in Kent alone? Sort of. I have certainly suggested that, caveats aside, there could be as many as 18,000 ponds occupied by gcn in Kent and the basis for this suggestion is detailed here. But seriously, are these 'differing views' really due to the fifteen minute presentation I gave at the 2006 Herpetofauna Workers Meeting? Let's be realistic here folks!

The talk that I gave to delegates at the 2006 Herpetofauna Workers Meeting illustrated the mechanism by which estimates can be derived from occupancy data. Remember it is the occupancy data that has contributed to the SAP process and the occupancy data is based on accurate and repeatable pond survey work. Of course, Mr. Fair was told this but has chosen not to make reference to it.

"He now says this was based on inaccurate data supplied to him about the total number of ponds in the county"

Emphasis mine. Now says? Possible issues with the Kent pond data were expressed during the talk and folks were reminded that the research was a work in progress. The information certainly was not presented as a definitive statement of fact.

Mr. Fair's article appears to have a moment of clarity when Natural England's Jim Foster is quoted as saying that:

"... the Kent data was not crucial to the revised figure."

Apparently, there is also:

"... consensus among scientists ... over numbers declining due to pond loss and fragmentation."

Unfortunately, things start to go downhill again...

"The revised SAP aims to increase the number of occupied ponds from 100,000 to 120,000 by 2010"

I agree that it is an ambitious target, but I don't quite share Tom's view that it is:

"Pie in the Sky"

In fact what the SAP steering group hoped to promote was widespread pond creation. As Jim Foster is quoted as saying, the target will be met by:

"restoring and creating appropriate habitat using agrienvironment measures."

The idea is to encourage creation of ponds that score relatively high on the HSI system. The process of pond creation and the high target were inspired by the Million Ponds Project, a major new initiative being organised by Pond Conservation that is due to start in 2008.

A million ponds! How many of those will be occupied by gcn? Perhaps the SAP target aimed too low?!

In summary then, the BBC article attempts to create a storm, but in reality it achieves little more than a drizzle. Which is a shame. No really! I believe that surveying for amphibians (and reptiles) is extremely rewarding and collecting data that enables us to more accurately make predictions regarding the distribution of threatened species is really quite exciting. We also absolutely need folks to challenge the status quo. Tom has done that and all credit to him. However, Tom has been let down by a journalist who has promoted drama over fact.

During my interview and subsequent exchange of emails I made it quite clear to Mr. Fair that the 18,000 gcn ponds quoted in my 2006 talk had not been the basis for the countrywide estimation of 100,000 occupied ponds. I also alerted him to the Pond Conservation project. Mr. Fair has been very selective in the information presented within his article and frankly I consider the article to be rather shoddy journalism. I guess that given the spate of reports concerning the cheating and misrepresentation of information that the BBC has now admitted to, it shouldn't really come as a great surprise.

On a much more positive note, if you are interested in learning more about the ongoing great crested newt survey work in Kent and would like to hear me present the now infamous talk entitled 'How Many Great Crested Newt Ponds are there in Kent?', then look out for details of KRAG's AGM in January 2008!

Edit 22/10/07 to correct some minor typos.

In the Eye of a Very Mild Breeze

I'm sure some of you will have now read the 'news' item that was recently published in BBC Wildlife Magazine concerning estimates of great crested newt. The article appears to be an attempt to generate a story, where none really exists. Before explaining why I believe that the article is flawed I thought that it would be useful to provide a little background.

Back in 2006 I presented a talk at the Herpetofauna Workers Meeting entitled 'How Many Great Crested Newt Ponds are there in Kent?'. The summary for this talk is reproduced below:

"The great crested newt is believed to be experiencing a national population decline greater than that of the other widespread amphibian species. In Kent the species remains relatively widespread, displaying a county distribution that appears to be dependent upon pond density. Surveying for newts is labour intensive and requires multiple pond visits to reliably confirm presence/likely absence. Assessment of newt populations using simple counts is problematic due to variation in detection rate between ponds and observers. Habitat proxies are increasingly being used to predict the likely presence of great crested newt. This study collected habitat proxy data using a published Habitat Suitability Index. Ponds were ranked based on apparent quality and surveyed to determine the relationship between predicted and actual presence. "

The talk illustrated how occupancy data can be used in conjunction with information on the number of ponds to make predictions on how many of Kent's ponds are likely to be occupied by gcn. The process is really quite straightforward.

1. How is gcn occupancy influenced by pond quality?

2. How many ponds are there?

1. How is GCN Occupancy Influenced by Pond Quality?

The likely presence of great crested newt in a pond can be predicted using a published Habitat Suitability Index (HSI):

Oldham, R. S., Keeble, J., Swan, M. J. S. and Jeffcote, M. (2000) Evaluating the suitability of habitat for the great crested newt (Triturus cristatus). Herpetological Journal, 10, 143-155.

The HSI has previously been discussed on the blog and I have also prepared a summary of how the HSI can be applied elsewhere, but it is probably worth repeating some of the main points here.

The likely presence of great crested newt in a pond can be predicted by examining aquatic habitat features such as the presence of fish, waterfowl and water quality.

For ponds these data are used to calculate a HSI. The HSI is represented by a number from 0 to 1, the higher the number the more likely the pond is to be occupied by great crested newt. In order to help with the interpretation of a pond's HSI, ponds are classified with a description that is based on their apparent suitability for great crested newt. Thus:

It means a heck of a lot more to a landowner when you explain the likely presence of gcn in English rather than gobbledegook!

By undertaking detailed survey work in a large number of ponds across SE England I have found that ponds with relatively high HSI scores (good - excellent) frequently support great crested newt. Indeed, great crested newt have been recorded in more than 90% of the surveyed 'excellent' ponds! The relationship between HSI and actual presence is illustrated below:

Note also that although gcn are rarely encountered in ponds with very low HSI scores, they do sometimes occur.

By looking at a large number of ponds, I have also been able to estimate the proportion of ponds with each of the different quality ratings. For example, while 24% of ponds are likely to be 'poor', only 12% of ponds will be 'excellent'.

The overall % of ponds likely to support gcn will therefore be:

(available poor ponds x occupied poor ponds) + (available below average ponds x occupied below average ponds) .... + (available excellent ponds x occupied excellent ponds)

For gcn I have generated an overall occupancy of 44%. This means that gcn will be present in almost half of the county's ponds! However, do consider that this is a county average. In some areas (e.g. countryside around Iwade), gcn occupy almost all suitable ponds. In other areas gcn may not be present at all, even in 'excellent' ponds. The presence of gcn in suitable ponds will largely be determined by the newt's local population status. A pond can be top notch quality, but if gcn are simply not present in the local area they may not have been able to colonise. Conversely, low quality ponds can be occupied, especially when they are situated close to another pond that already supports the species.

I also suggest that although a pond may be occupied by gcn, the amphibians may not necessarily breed there. My own survey work indicates that breeding success is more likely in ponds that are rated as 'good' or 'excellent'. The implications of this are that although gcn may occupy 44% of the county's ponds, they may only successfully breed in 27% of them.

2. How Many Ponds Are There?

In Kent, information on the number of ponds has been published by Kent County Council (KCC) and is freely available through the Kent Landscape Information System. From the website:

"The purpose of the K-LIS website is to enable better informed decision-making by providing detailed information on Kent's landscape and biodiversity. Primarily aimed at landowners, farm advisors and those involved in land use planning, the website also acts as a useful information source to members of the public. This site contains details on countryside access, landscape character, identifies opportunities for habitat creation and landscape restoration, the physical environment including soils and geology, the Kent habitat survey as well as areas designated for their conservation value."

The Kent and Medway Biological Records Centre have very kindly analysed this data on my behalf and suggested that there may be more than 41,000 ponds in Kent. Wow!

So, how many great crested newt ponds are there in Kent? Some simple maths:

41,000 ponds x 44% occupancy = 18,000 occupied ponds

That is an enormous number of occupied gcn ponds. However, as I very carefully explained during my talk at the Herpetofauna Workers Meeting, this is a preliminary finding and subject to verification. During the talk the audience were specifically told not to quote the figure due to concerns over the validity of the KCC pond count. What are those concerns? Look at the map below:

It is apparent that there are a large number of waterbodies on Romney Marshes, North Kent Marshes and North East Kent Marshes. These waterbodies are almost certainly ditches and drains - not ponds. Great crested newt can (and do!) breed in ditches and drains. However, the HSI was not developed for use on these waterbodies and does not take account of habitat features that may be unique to these linear waterbodies. For example, ditches often contain flowing water that could wash away gcn larvae. Ditches may also form an interconnected system that is seasonally flooded with brackish water and/or fish. The Kent pond data should more accurately be called Kent pond + ditches/drains data. At the present time it is unclear what impact this will have on the actual pond count. However, one thing is obvious: 41,000 ponds is an overestimate.

Some Conclusions

1. Kent is one of the best surveyed counties in the country and the amphibian survey data collected by KRAG volunteers is a tremendously useful resource.

2. Survey data has enabled me to estimate overall occupancy of ponds by great crested newt. As new data comes in estimates of occupancy may change a little. However, based on available information I predict that 44% of Kent's ponds are occupied by gcn.

3. GCN will not successfully breed in all occupied ponds. The loss of a single 'excellent' pond could therefore lead to the loss of gcn from several other lower quality ponds that are situated nearby.

4. Very few counties have detailed habitat data. Kent is extremely fortunate that KCC have funded a wide-ranging habitat survey. Data from this survey is currently used to inform conservation, management and planning across the county.

5. There are concerns over the accuracy of the Kent pond data. The quoted figure of 41,000 ponds is likely to be an overestimate. However, the actual number of ponds is considered to be in the same order of magnitude. Even if the inclusion of ditches and drains has doubled the current pond estimate, that still represents a tremendous number of ponds. Kent is probably one of the most import reservoirs of freshwater habitat in the country.

6. The KCC pond data may be inaccurate, but it is all we have. At this time I would prefer not to quote the figure of 18,000 occupied ponds for gcn in Kent. Yet this estimate remains valid based on the existing KCC dataset.

7. While any estimate of the numbers of a species are likely to have margins of error, I would urge KCC to consider reanalysing the Kent pond data so that we can make a revised and hopefully more accurate estimate of the number of gcn occupied ponds.

Next up, I will review the BBC Wildlife article and explain why I believe this particular journalist got things so wrong.

Unusual Lizards at Folkestone Warren

There have been reports of 'unusually marked lizards' from the area around Folkestone for several years now. In May 2007, Julian Russell and Nigel Jarman discovered the truth...

As many readers of the blog will be aware, I have been keenly following the history of Kent's sand lizard. I have previously posted a summary of our current knowledge. There are two records for Folkestone Warren (1967) and a single record for Sandgate (1969). The latter is a verified record of a juvenile sand lizard that was observed by Keith Corbett.

In 1995, Anne Riddell visited Copt Point (just along the coast from the Warren) and recorded an unusually marked lizard. Anne was convinced that the animal was not a viviparous lizard. Could this have been one of the elusive sand lizards? Anne's description of the animal is as follows:

"Size of adult common lizard, tail shed at junction with body. Body and head stockier than common lizard.

Colouration: dorsal - brown

flanks and legs - apple green

flanks and belly - marbled (not spotted) cream and black, exactly like grass snake.

Hunting actively in grass tussocks for insects seen at 12” distance."

In 2004, another report was received from friends of Sean Hanna. This time the animal was seen at the top of the Warren. Sean reported the following:

"As promised, I have quizzed my friends who thought they saw a sand lizard in Folkestone. They thought it was too large to be a common lizard and that it was the wrong colour."

KRAG members have made several visits to the area (some examples are documented here: 6/9/04, 16/9/04, 24/9/04, 30/9/04). However, the habitat around the Warren does not look particularly appealing for sand lizards and although viviparous lizard, slow-worm and adder have all been recorded, sand lizard observations remain elusive. Over the years Eric Philp has also attempted to track the beasts down, but <a href="http://homepage.mac.com/calumma/iblog/C2026029206/E9948045/index.html">without success</a>.

There has been a suggestion that the Folkestone Warren records may originate from a failed introduction. But did the introduction really involve sand lizards? Back in 1996 Phil Shore told me an interesting story:

"Also I remember Lee mentioning large green lizards at Folkestone. Alan Cooper -the Burnt Oak Wood warden told me a number of Wall Lizards were released there by a pet shop owner who was unable to sell them. Given the unusually mild micro climate of the site it is possible the lizards are still there."

So, could the Folkestone mystery animals really be wall lizards? In our hunt for sand lizards we have tended to search the top of the Warren and there is one specific area lower down that has not been adequately surveyed. Earlier this year Julian Russell and Nigel Jarman visited the Warren and may just have solved the mystery:

"Having been alerted to the presence of green spotted lizards at [Folkestone Warren] by Peter Harnett via Nigel Jarman on Thursday 3rd May (Peter thought they might be Sand Lizard although views brief) I checked the site at lunchtim (1.00-1.15) on Tuesday 8th May and found three Wall lizard sunning themselves. A number of photos taken before they sun went in and the lizard retreating under a yellow door, Nigel Jarman saw them later although they quickly disappeared when the sun went in. Fantastic to see these Lizards in Kent as I went to Bournemouth last year to look for them. Subsequent emails to Lee Brady inform me they were known to KRAG and had been present for 20 years!! The cafe owner was please someone was taking interest in 'her' lizards - she said they had been there at least 5 year but she didnot know where them came from. She also said she had had adders in her cafe and in the ladies toilets which she just picked up with a litter picker and release unharmed.

Nice to see such a positive attitude."

Julian was also kind enough to email me the following photos. Well done to all and what a fantastic find!

In order to protect the site I have not identified the exact location of these observations. However, if you do visit Folkestone and see an unusually marked lizard please do let me know!