Tuesday, June 19, 2007

Hedgehogs - again.

Just in case our Trevor, Mr. Lawson of the Badger Trust failed to get the message, or, as in the case of the last CSL badger / hedgehog census, did a crafty spot of grammatical gymnastics on his press release , Defra have released another part of their head count.

In a a paper now available on the Defra website, they say;

....In particular, hedgehogs are thought to be particularly vulnerable. Research by CSL in conjunction with the Randomised Badger Culling Trials (RBCT) revealed that hedgehog abundance and distribution were negatively correlated with indices of badger density. Even in suburban habitats the abundance and probability of occurrence of hedgehogs declined rapidly as indices of badger density increased in the surrounding areas
.

Got that? In plain English, too many badgers = no hedgehogs. They eat them like an orange we are told. Roll the little poppets on their backs, spread out their legs and peel them like a Jaffa, leaving just the skin behind. Nice.

30 comments:

Jo said...

Friends were walking home through the village the other night and saw a badger. It was running out of a neighbour's garden with a hedgehog in its mouth.

Anonymous said...

OK, you've lost me on this one. why on earth is it wrong for a badger to eat a hedgehog?

Matthew said...

Anon. 9.06
It isn't wrong - in small doses. That's nature. What is hard to swallow - if you'll pardon the pun - is Trevor Lawson's attempt to alter the information coming from CSL, which is that too many badgers mean no hedgehogs at all.

We've posted other work that has shown that when the badger population outgrows its naturally available supply of earthworms, then as an opportunist omnivore, many other species are hoovered up. Some to complete extinction in that area. That is imbalanced.

Years ago, two contributers avoided mowing around nests of grey partridge and skylark. It was a pleasure to see and hear them. But when badger numbers exploded, they disappeared altogether.
For us (Matt 3) the pheasant and partridge are back. For Matt 1 his skylarks are not.

Anonymous said...

Farmers' Motto -

NATURE MUST BE CONTROLLED

Anonymous said...

'It would be so helpful if Defra embraced the science and helped farmers and their representatives prepare a science-based course to better control of cattle-borne TB instead of pandering to the voice of the NFU
who are saying cull, cull, cull."

Anonymous said...

Let's get back to the main agenda - killing badgers.

What a shame the scientists don't think it's on.

Everyone is still waiting for the explanation of how would propose differentiating between the sick and the healthy badgers.

For instance, David Handley of 'Farmers For Action' has warned Miliband that 'farmers will refuse to TB test unless action taken on badgers' and says "It is the sick and unhealthy badgers we want dealt with in order to protect our healthy badgers".

How?

Don't forget PCR is not an option (yet)

Matthew said...

Anon; 1,25 Not 'controlled', managed.
We would not expect to keep twice the amount of cattle our land could support - why should badgers be any different? And yes, we know that they control a pregnancy to bodyweight, but given an unlimited amount of feed, over and above earthworms, that is not a limiting factor.
Anon: 1.27 Defra advise bio security. Been there, done that lost over 40 head of home bred cattle. Cheeseman got it right when he told shocked audiences that it was impossible to prevent interface between badgers and cattle. "You can't" he said, "Get rid of your cattle".

Anon 1.33 We're goiung to turn this around and ask you: if PCR could be employed in detection of positive infection within the environment, and once cattle borne infection had been ruled out in a herd breakdown, would you support a targetted cull using it?

Until then - and it would be helpful if all factions pushed hard for the use by Defra of this stunning technology, not least for H5N1 avian flu, FMD, CSF and a host of other nasties - then the tools we have available are sentinel cattle, testing positive to Tb, backed up with WLU experience to target which setts are responsible. For the last years of the 'interim strategy' that option was limited to 'land on which reactor cattle had grazed', thus leaving setts in neighbouring land, forestry etc. to fester unhindered.

As we have said, a gamekeeper's method was to leave a main sett but gas off sets regularly to both manage population density, and mop up any old, weak or sick individuals excluded by the main group. Deer management works on the same principle.

Anonymous said...

Here's a quote from PTES (People's Trust for Endangered Species,currently investigating hedgehog decline)
"Two well-documented dangers that hedgehogs face every day, we can quickly discount; road deaths and predation by badgers between them are not likely to have brought about the massive losses we're looking at in such a short space of time. ....We needed to look further afield. Our attention turned to factors that have affected other species that share the same habitats as hedgehogs, namely farmland birds. In the face of vast agricultural intensification over the last sixty years, and the fact we know how devastating this has been for farmland birds, it would be very surprising indeed if these same farming practices hadn't affected hedgehogs in the same way.

So concerned were we that we recently asked Joanne Bunner of RHUL to do some preliminary work looking at how farmland chemicals, and particularly molluscicides (chemicals used to kill snails and slugs) and pesticides, affect hedgehogs. It seems that if the former get into a hedgehog's body they prevent vital messages being sent around its nervous system properly and this can lead to the death of the hedgehog, or, at the very least, cause it serious harm.

Even more important are the effects of the more widely used pesticides. They have an enormous impact on hedgehogs by killing off all their insect food supply and depriving them of the good nourishment all living things need"

Still, easier and more convenient to blame badgers isn't it (even though they are an indigenous species who is part of our natural food chain and has been around a lot longer than us)?

Matthew said...

Anon:12.59
The paper you quote is severely out of date. The whole point of the new CAP directives, operative from 2005 is that farmers do NOT need to produce food anymore, thus 'intensive' agriculture is an emotive adjective not backed up by reality. By directive we have to leave 3m margins around all fields etc. some of us have been avoiding mowing skylark nests for years, without being told and drawing up a plan, but let that pass.
The CSL research which we quoted compared 'amenity' land to 'pasture' land, and did a census on the inhabitants of both. Slug pellets are not used on pasture land - at least not to my knowledge. They are an arable input.

We have no problem with an 'indigenous food chain', providing species right at the top do not dominate. The optimum words, I think, are 'part of'.

Anonymous said...

I have emailed both PTES and the Hedgehog Preservation Society for an update on their conclusions, and will let you know their response when I have one.
As for your comments re 'intensive agriculture'I have to say, if only that were true! I live in a farming area, and can promise you there's plenty of pesticide/herbicide/ chemical controls/artificial fertiliser use/habitat destruction still taking place...And hedgehogs are not the only species being affected.
What is your undestanding of the term 'balance of nature', if I may ask? Why do you think - after millions of years - that one INDIGENOUS species is no longer kept in check by the natural and built-in mechanisms to control its own population numbers (and preserve its own prey species and food supply) so that it is driving another (prey) species to extinction? Do you know of a single example of that happening before in nature? I would be interested to hear it if you do.The reality is that humans interfering by culling has ALWAYS caused problems in the natural balance (I am not talking obviously about introduced species here): the Mammal Society for example, tells us that direct culling by humans is responsible for the loss of at least 10 mammalian species.

Matthew said...

Anon:12.0)
Around us it is mainly extensively farmed, some organic, grassland, with a little arable intermixed. A lot of woodland which is ideal for badgers.

Grassland farmers will use manure, and artifical manure but very few if any pesticides, herbicides etc.

Your reference to the 'indigenous' species population control, we presume you mean a badger's implanted pregnancy which only matures with its body weight. That is totally dependant on available food. Hence the progression from earthworms, referred to as 'the badger's main diet', to well, anything other available source.

We have named them but they include (from personal experience) newborn lambs, calves, placentas corn and maize. From wildlife experts' published work, hedgehogs, hamsters and rabbits; slow-worms, skylarks and lapwings; pheasants, partridge, frogs, newts and bumblebees.

By the 'balance of nature', if any of these are to survive - and why should they not? - then as the food supply available to this opportunist omnivore is practically without limit, then it is the responsibility of man to put a limit on its population numbers in order that this 'balance' may be struck.

In this country, the only predators of badgers has long since gone - bears and wild boar - so the species is at the very top of a diminishing food chain.

Anonymous said...

I've been watching badgers for 30 years now (on and among sheep and cattle farms) - I've never seen them do anything except run away from sheep (even lambs) and cattle.The lambs often inquisitively investigate the sett entrances and this immediately causes the badgers to go back down and not reappear for some time...I was once watching with my cat...The cat went towards them and growled and the badgers ran away!! There is absolutely no way they would take any new born lamb or calf unless it was extremely weak or already dead, and its mother was nowhere near. I asked the farmer whose land it is and he said he had never known of a lamb to be taken by a badger, nor did he know of anyone who has.
As for humans and the balance of nature....Badgers are not a food species for humans and as such we are not a natural predator. Badgers are top of the food chain in Britain (along with foxes) and have been for centuries. No predator species will drive any prey species to extinction if they are both in their natural habitat. Do you know of one single example of this ever happening? I only know of one species that destroys its environment and elements essential to life....and for that we just need to look in the mirror.
The natural mechanisms which limit badger(and all predator)numbers are complex and involve many factors, including available food supply and land available.Why on earth do you think earthworms (which form I believe around 80% of the badgers' diet, (followed interestingly by - for example - huge numbers of cutworm larvae)would 'run out'? What evidence can you possibly have for this assertion? The other species you mention (as well as - for example - baby rabbits and fox cubs)are indeed part of the badgers' diet as they are opportunistic and omnivorous feeders - but the ones you mention in fact only form a tiny part of that diet.It is interesting to note that in one university study on elements of the badger diet, they in fact found that more ground nesting birds lost eggs and nests through being stepped on and crushed - and eaten - by cattle than by badgers!

Matthew said...

Anon 5.40
We had a healthy calf shot, because a badger had bitten through its spinal column above its tail. It had rolled under a wire back fence, and its mum couldn't protect. It does happen.

You are quite correct to cite 'food availability and space' as precursers for successful survival. And also right when you say ' badgers are at the top of the food chain'. So take that one step further.
Ten years ago we had 2 badger setts on 200 acres. In 2003, that had increased to 5/6 (RBCT mappers) but they missed 3 setts. Over the 10 years 2 had become 9.

I believe that the population increase was fuelled by our neighbours and ourselves growing maize, allowing more cubs to survive the winters. That coupled with a few mild and short winters.

Now, 200 acres supported a couple of groups in 2 setts quite happily for 20 years with no problems. But 9 setts? How many badgers were there then on our 200 acres? Local housing development and road widening in the 5/6 mile foraging area deprived them of even more food opportunities for earthworms. So what do they do? Local householders reported bird tables raided, dustbins tipped over and pet hamsters etc chomped up. Our cattle feeding passage became a mecca - and unfortunately this we only discovered too late to save several cows.

Too many badgers on a decreasing acreage - and certainly not enough earthworms for a 4 fold increase in population. They had two choices. Stay and starve or adapt to a more 'varied' diet and survive, which is what they did, to the detriment of the wider ecology on this farm.

Anonymous said...

Why on earth is 9 setts on 200 acres any sort of problem? That's not a very high density...
You will often get just one or two individuals using a sett at any one time - and sometimes setts are simply not used for a while.There are main setts, outlying setts,subsiduary setts, birthing setts...of many different sizes/rates of use.As I said on my other post, you are probably often seeing the same badgers at different setts.
To be honest, if you only had 2 setts for 22 years, something very wrong was happening with your badgers!
I recommend that you find out a bit more about badgers.

Matthew said...

Anon.9.11
These were marked as 'main setts' - occupancy 8/10 in each. (Three were missed by the WLU mappers and were single holes).
And having lost over 40 home bred cattle to them, I have taken the time to find out why.

Matthew said...

Meant to say - at their second (and last) swipe, the WLU told us they'd taken 76 from this valley. So your "two moving around" appears optimistic. From the increased trails, damage and the size of the setts etc. we reckoned we had close on 100.

Anonymous said...

That's NOT a high density on 200 acres and certainly would not cause any problem with earthworms or any other perfectly normal part of their diet.
In what way have you 'lost 40 home bred cattle to them'?? Because you're blaming them for TB? Or because they ate them??
Still interested to know if you think wild birds should be culled to stop the spreading of avian flu....

Anonymous said...

Who are the CSL by the way?

Matthew said...

Central Science Laboratory - Woodchester Park.

Anonymous said...

Hang on a minute - something isn't adding up here...
First of all, are we talking about your farm Matthew, of 200 acres, or are we talking about 'this valley' ? Or are they one and the same? And if not,how many acres does 'the valley' cover (aprox)? And which does this estimate of '100 badgers' refer to, since the '76 badgers in the last swipe'(??) refers to 'the valley'?
(I notice by the way that your most recent post has been sandwiched belatedly between your previous one and my reply, somewhat distorting the sense of my reply - which was to your preceding post, not to the add-on)
Now you say the RCBT mappers marked 5/6 'main setts' in 2003, and that you subsequently found "three holes in the ground".That does not make 9 setts!! Since there will always be smaller subsiduary and outlying setts attached to main setts,as well as boltholes (your 'holes in the ground'), where are they in this 'map'? I'm sure you would have included them if they were over and above the 'main setts' mapped if you're going to include 'holes in the ground'! And as I've already pointed out, badgers in any family/social group will move around between the subsiduary setts on their territory and their main sett so that - as I've said before - you may well be seeing the same badgers at different setts ( but where did I say the same TWO badgers??)
So it looks as if it's your 'estimate' of 100 badgers on 200 acres that comes from Fantasy Land.
Also you seem reluctant to say whether you would support a cull of wild birds in the event of an avian flu outbreak? Why is that I wonder?

Matthew said...

Anon 8.37.
Enough.
We answer if and when we can or when appropriate. We do not have to, and if a thread gets bogged down, pedantic or antaganistic we will delete the post.

To answer your question: Our 200 acres includes a wooded valley approx 2/3 miles long. Main sett activity increased in this narrow woodland from 2 at the start of RBCT mapping (2 which had been a constant over time), to 5/6 main setts in 2003. The river is the boundary, and our neighbours have setts on their side too.

The setts the mappers missed on this farm were 3 single holes away from these and not too far from the building complex. They were not found until after silage had been cut in mid May.

It was the occupants of these (we suspect) who entered the feed passage during winter /spring 2003. And after a graphic description of them in May 2003, when they were caught by the WLU we lost the bulk of a group of in calf heifers, 3 of which were the only cattle taken from this farm to show positive infection at postmortem. That summer we were as low as we have ever been.

It took another year to get the herd clear of exposure to this infection, and with the exception of one blip last autumn, we have remained clear. Three neighbours whose farms border the valley are also clear after years of restriction and several hundred dead cattle.
We are testing again this week.

H5N1 Avian flu is not the subject of this blog. rtPCR technology to locate and diagnose is, and if you haven't picked up on that, you haven't been listening.

Anonymous said...

Matthew said "We answer if and when we can or when appropriate. We do not have to, and if a thread gets bogged down, pedantic or antaganistic we will delete the post."
This is a different anon here. I would say this thread is anything but bogged down, it's produced an interesting debate - unlike the Trevor Lawson debates and unlike the sniping at the ISG. If the matthews want to criticise others, they can't back out when the going gets tough.

Matthew said...

New Anon 10.25
This site was started 3 years ago to 'debate' the Tb situation. As a 'new' Anon, you may not be aware of our backgrounds, so we will post our answer to a previous message here:

"Four of us have been involved in the RBCT and have similar stories.
As you quite rightly say "we are nobodies" - just cattle farmers.
However that does not negate our observations of Krebs' protocol, of RBCT methodology or its chaotic and entrely predictable results, but it does preclude the editors of Nature, Science, Vet times etc., from publishing.

Our experience of the RBCT is now mirrored in statements to EFRAcom from wildlife team mangers (Paul Caruana) vets and ex SVS personnel and comments on this site from WLU operatives which we are happy to post. That the RBCT dossier has passed into the realms of 'science' is a matter of speculation as the true meaning of the word, as Dr. Gallagher pointed out in his 'Opinion' piece.

The point of this thread was to muse on the way badger epidemiology and social group habits already researched, accepted and published, were so disregarded by the ISG as to make such a predictable result of the RBCT.

And for that we may have to revisit the very beginnings in 1997, when Bourne told a practising veterinarian that 'No way was Government going to cull any badgers, so the trial would centre around cattle to cattle transmission'.
This in 1997, before it started??

And cattle/cattle is what the RBCT report has centred on. But with the greatest of respect to Professor Bourne et al, it does not answer our questions as to where did pernicious and persistant Tb infection in our herds come from, if no bought in cattle are involved? And if the other side of that known and acknowledged Tb reservoir is not removed, how on earth do we get the cattle clear?

But Dr. Cheeseman has already answered that, and Bourne's report sneaks it in. You get rid of your cattle.

That doesn't help the badgers and will not prevent the inevitable spillover into other mammalian species - a situation already on the rise and documented in cats, camelids, pigs, sheep and dogs.

The other uncomfortable (from the point of view of Defra) consequence of this prevarication, are the high profile challenges of people who farm a few Dexters or companion cattle, often organically, and are not prepared to conform to a rigid Tb protocol of killing them out, only to be reinfected by an untouchable source."

The 'going was tough' when we were in the middle of 60 day consecutive testing on home bred, much valued cattle. The stress, anger, questions and answers to that make this a breeze.

But first and foremost, we are working farmers. Our herds and businesses take priority. This site is an attempt to communicate what actually happened on the farms involved with the RBCT and with Tb problems, to a wider audience.
To that end we have been accused of lying, moving cattle illegally, being 'economic' with research etc. etc.

We repeat; if a hypothesis does not fit our particular situation - and with cattle / cattle spread of Tb it did not, then that hypothesis should be challenged. Whoever has made it.

We have also explained out concern about some of the statistics and information, tortured through computer models and extruded as 'fact'. This from the point that, (from those taking part in these research projects) much of their cattle / badger / habitat or badger behaviour information was excluded. Can the result therefore be relied upon, if half the input was missing?

Not for us to say - of course.

Anonymous said...

And I would repeat that you should put your accusations either in a comprehesive letter to a journal carrying one of the ISGs papers or perhaps to defra. This would be generally considered to be the professional way to go about things. To criticise the ISG and the science using rude names and quote marks will get you nowhere. your suggestions for other methods of controlling the disease may be valid but this is not a way of getting them taken seriously. alternatively, restrict your blog to discussing bovine tb and ways of controlling it rather than trying to discredit respected scientists.

Matthew said...

Anon 2.42
Nothing to add to the above precis.

"discredit respected scientists" ??

They do that all by themselves, and respect has to be earned.

We note that Professor Koch's picture appeared in the front of the ISG report. If Prof. Bourne had taken the trouble to examine Koch's 'Postulates', or the Evans postulates which followed them as the 'gold standards' of epidemiology, there would have been no need for the RBCT at all.

Anonymous said...

Original anonymous here!

Matthew (or one of the matthews! Must admit I was beginning to wonder when any farming got done!) said

"The point of this thread was to muse on the way badger epidemiology and social group habits already researched, accepted and published, were so disregarded by the ISG as to make such a predictable result of the RBCT."

Actually,this thread was about hedgehogs - and your completely ungrounded assertion that badgers are responsible for the decline in hedgehogs....It isn't me who hasn't been listening!

"This site was started 3 years ago to 'debate' the Tb situation."

A 'debate' means both sides putting their arguments, and will generally only work if both sides listen, and reply. By ignoring questions or arguments you don't like, and that don't fit your hypothesis, you're making this a rant, not a debate.
Also you keep repeating yourself, even when contrary evidence has been put forward...And then accuse other contributors of getting 'bogged down'.

"We repeat; if a hypothesis does not fit our particular situation - and with cattle / cattle spread of Tb it did not, then that hypothesis should be challenged. Whoever has made it."

Exactly, Matthew. That's just how I feel about your hypotheses. But I see you don't like being challenged yourself.

"...respect has to be earned."

Too true.


Maybe you should state clearly if you really want others to contribute to this debate, in the hope of furthering mutual knowledge and understanding, or you simply want an opportunity to rant about a subject you appear to have a completely closed mind about.

Matthew said...

'New' Anon;
The posting to which you refer as 'not about hedgehogs' was a reply direct to you, to introduce ourselves and headed " we post our answer to a previous message here". We meant a message on another thread.

We make no assumptions re badgers v. hedgehogs, we quoted CSL data, Badger Trust 'overview' of the same data and updated it with our own observations of wildlife on our own farms.

We are listening re. badgers. We questioned Ministers hard re. badgers, their habits, biology, epidemiology and social structure.
The effect of too many on the ecology and the effect of Tb on the species themselves. All PQ answers are archived on the site.

Anonymous said...

Re causes of hedgehog decline:
I have now had a reply back from Nida al Filaij, Development Manager at PTES:

"It is...not a matter of one native species affecting the other but a culmination of a combination of factors. I can't think of any other examples and it's likely to happen in isolation. Although farming isn't as intensive as it once was, in some areas field sizes are still enormous and there is very little biodiversity with regards to plants and habitat, and therefore with what other species can live there. Pesticides aren't used in such large amounts but they are still used. Road density in the UK is the second highest in Europe. All of these factors are likely to be affecting hedgehogs... (And although in some local cases where hedgehog populations are already seriously reduced they may also be affected by badger predation)..badgers shouldn't be made the scape-goat for all these things."

Now I'd say that was fairly clear. So just in case our Matthew has failed to get the message, badgers cannot be made the scapegoat for hedgehog decline.
And you have STILL failed to produce a single credible reason why you believe there are 'too many badgers' in the first place.

Matthew said...

Anon: 11.30
Try this:
http://bovinetb.blogspot.com/2005/02/total-protection-for-badgers-sense-or.html

Posted Feb 2005, published paper from Dr. W. Stanton, Somerset Wildlife Trust.

Anonymous said...

Now we've heard from someone who is in a position to know about hedgehogs (see my previous post),and who contradicts the assertions made on that subject by the matthews, let's turn our attention to the bizarre assertions of the ex-trustee of Somerset Wildlife Trust, Dr W. Stanton elsewhere on this blog (see reference in above post).
The idea that humans (that wise and environment-preserving species, whose activities are currently wiping out other species all over the world at one thousand times the natural background extinction rate - and rising) is somehow ordained (by God? By nature?) to preserve the balance of nature by intensively farming some species while persecuting other native wildlife species, is one that I think not many sane individuals could still claim to be based on any reality, let alone evidence.
All the evidence in human history to date points to exactly the opposite. We interfere in the balance of nature at our peril, we should SURELY have learnt that by now.
Red squirrels, incidentally, were abundant in the early 1900s, and were considered a 'pest' by farmers. 'Squirrel shooting clubs' were formed, and in 3 years alone in the 30s, 87,000 red squirrels had been shot by one such club alone. By the time the introduction of grey squirrels, destruction of habitat and the spread of squirrel pox began to make themselves felt, red squirrel numbers had been too seriously depleted to be able to withstand these threats. As a PETA spokesperson said last year-
"Anyone can see what mistakes we shouldn't have made in the past. The trick is to see what we shouldn't be doing now"
Badger numbers are, mercifully, healthy now they are a protected species. Like wild birds with avian flu, badgers can contract bTB but it is generally not a problem for them (witness the small proportion of badgers who are infected who actually progress to the active and infectious stage of the disease). Wildlife species whose numbers are healthy are in a much better position to develop natural immunity to diseases that have become a problem because of hunman intensive monoculture (or near monoculture) of a few domestic species.
Which is exactly why people who care about wildlife DON'T think that killing more badgers is going to help them (or any other species).Tackling bTB at source - domestic cattle - will.