Forest of Dean Wild boar Population : Is the research data correct?

[Cyres]

Further to the post on here about the potential of the boar population being over culled with a population of now 400 I suggested that from an night time walk with a thermal N of Lydney I suggested the figure was wrong.

Clearly this was unintentionally a little controversial.

Subsequently I have pulled the latest Forestry research data for the 2021 survey.

The Fod is approx 110 km2 and according to the data 80.9 km2 was surveyed.

In 2019 survey was sounders and nos 163 x 2.98= 485 boar
In 2021 109 x 4.23= 461 boar 95% confidence limit are 623/1405 boar

All well and good but then look at the cull data

Year	Estimate Population	Target Population	Cull Achieved

18/19	1635	400	450
2019/20	1172	400	1002
2020/21	No survey undertaken due to COVID	400	TBC
2021/22	937	400	Ongoing

If you look at the 2019/20 cull data population estimate was 1172 yet 1002 were culled so should have been 170 left but the target population is 400.
20/21 no survey but in 21/22 estimated population was 937 cull figures not available.

Also it appears in the date there was a drop in RTA's but surely this is not unexpected as we were in the lock down and traffic flows were massively reduced.

This is only the Forestry England data. How many boar are culled by private guns in the the Fod?

If the above data is correct then in 2019/20 85.5% of the estimate boar population was culled by FE staff! . So 14.5% left to be targeted by other shooter. Clearly the population estimate has to be incorrect as such cull levels would be unsustainable/unachievable and boar would be extinct. Perhaps some of the SD members who advertise boar shooting in the Fod may like to input the numbers of boar they cull.

It appears that surveys were at night with thermal but the methodology is not stated. From my walk with a thermal in the Dean target acquisition is very difficult due the heavy woodland/timber and undergrowth and the terrain is highly undulating and only a small percentage is visible at any time. I could see things my shorter colleagues could not see and I have had 6 years experience of thermal use 4/5 times a week. Once I got accustomed to what boar looked like through the thermal they were everywhere.

Also you need to look at the deer survey figures: when we went on the Fod railway my partner was spotting fallow everywhere. How on earth they can estimate the Munty population is beyond me.

Further food for thought:

Average litter sizes in the Dean are between 6 and 10 piglets, nearly twice that of their continental cousins. With few natural predators, plenty of food and shelter early survival rates for the piglets is thought to be high. Research also shows that some of the Dean’s wild boar reach sexual maturity in their first year.

How does this statement correlate with the survey data?

Some more data to look at:

Useful links
Deer Initiative’s best practice guide ‘Wild Boar Legislation’ www.wild-boar.org.uk
University of Worcester ‘The Social Aspects of Wild Boar in the Forest of Dean’
Distance sampling / thermal image survey reportsfrom Forest Research.

Annual Census Reports​

Feral Wild Boar Census 2018​

Feral Wild Boar Deer Dean Census 2018 (PDF 338.47 KB)

Feral Wild Boar Census 2019​

Feral Wild Boar Deer Dean Census 2019 (PDF 408.08 KB)

Feral Wild Boar Census 2021​

Feral Wild Boar Census 2021 (PDF 429.02 KB)
Can

Regards

D

 

[StephenToast]

Why don't you just ask The Forestry Commission?

 

[VSS]

.

Also it appears in the date there was a drop in RTA's but surely this is not unexpected as we were in the lock down and traffic flows were massively reduced.

I doubt that the drop in RTAs is a reflection of lockdown, although it sounds like a logical assumption.
I believe that there was an increase in deer - vehicle collisions during lockdown as the reduced traffic resulted in animals being bolder and spending more time in close proximity to roads. One would expect the same to be the case with boar?

 

[Sus scrofa]

If you read further into the methodology, which is widely available if you look hard enough, the census counts are not there to give a correct and complete figure as this is nigh on impossible. The census of Deer and Boar are done to give a trend in population statistics i.e. are the numbers increasing or decreasing?

 

[Lateral]

I heard a rumour, that extra people had been brought in, to increase the cull numbers, and that they were being paid per boar.

If this is the case, it won't be long before boar are eradicated in the FOD

 

[EMcC]

Why don't you just ask The Forestry Commission?

Ask five different members of the FC, add the five different figures together and divide by five and you will get a rough idea of what was culled

 

[phillips321]

I heard a rumour, that extra people had been brought in, to increase the cull numbers, and that they were being paid per boar.

If this is the case, it won't be long before boar are eradicated in the FOD

I heard the same...

 

[Cyres]

Surely as a government body they should provide accurate cull figures. It would be interesting to know how many FE staff are engaged in the boar cull and what is the breakdown of culled boar, adult sows and boar and juveniles. I note as yet no input from private boar shooters in Fod!

Perhaps a FOI request is needed.

D

 

[Night òwl]

Surely as a government body they should provide accurate cull figures. It would be interesting to know how many FE staff are engaged in the boar cull and what is the breakdown of culled boar, adult sows and boar and juveniles. I note as yet no input from private boar shooters in Fod!

Perhaps a FOI request is needed.

D

All the current rangers were tasked with culling the boar in the dean to have a significant impact on numbers , hence why deer stock numbers has increased so much over the last few years as all resources were channelled into the feral wild boar population.
They have no official classification ,so pregnant sows , matriarch sows , males, piglets etc are all in the cull plan at anytime of the year.
The main brief was to bring numbers down substantially and as quickly as possible which is why more rangers were recruited, night shooting was then introduced to increase cull numbers even more especially culling farrowing sows .
On top of that your had several outfits in the dean offering boar high seat shooting but cull numbers from those is not significant as usually single animals a few times a week.
Poaching was a huge issue at one point and there are several individuals who was culling large numbers on private ground around the dean removing 30/40 a month.
All this has had a huge impact on numbers , plus the FE continue to cull every animal seen if safe to do so.
It would not be 100% accurate because some rogue rifleman do not carry out trichenella tests but the majority of responsible individuals, private estate and of course FE all send trichenella tests to the APHA as it is a legal requirement.
These test are recorded with the area the animals were culled in so would have a high accuracy of numbers culled to date, I am unsure if this data would be available to the general public.
I myself keep all my trichenella tests and cull areas to gauge the density and numbers I have shot , I know most keep detailed records

 

[Sus scrofa]

I heard a rumour, that extra people had been brought in, to increase the cull numbers, and that they were being paid per boar.

If this is the case, it won't be long before boar are eradicated in the FOD

Well your source/rumour couldn’t be more wrong if they tried. Only FE Rangers shoot on FE ground in the FOD. No contractors, no leases-don’t let anyone tell you differently.

 

[Sus scrofa]

Surely as a government body they should provide accurate cull figures. It would be interesting to know how many FE staff are engaged in the boar cull and what is the breakdown of culled boar, adult sows and boar and juveniles. I note as yet no input from private boar shooters in Fod!

Perhaps a FOI request is needed.

D

They do provide and publish accurate figures. It has always been stated that the aim is to reduce the population to 400 feral wild boar.
I think if the private shooters actually published their figures, they may scare themselves with the amount collectively culled in and around the FOD

 

[Sharpie]

Further to the post on here about the potential of the boar population being over culled with a population of now 400 I suggested that from an night time walk with a thermal N of Lydney I suggested the figure was wrong.

Clearly this was unintentionally a little controversial.

Subsequently I have pulled the latest Forestry research data for the 2021 survey.

The Fod is approx 110 km2 and according to the data 80.9 km2 was surveyed.

In 2019 survey was sounders and nos 163 x 2.98= 485 boar
In 2021 109 x 4.23= 461 boar 95% confidence limit are 623/1405 boar

All well and good but then look at the cull data

Year	Estimate Population	Target Population	Cull Achieved

18/19	1635	400	450
2019/20	1172	400	1002
2020/21	No survey undertaken due to COVID	400	TBC
2021/22	937	400	Ongoing

If you look at the 2019/20 cull data population estimate was 1172 yet 1002 were culled so should have been 170 left but the target population is 400.
20/21 no survey but in 21/22 estimated population was 937 cull figures not available.

Also it appears in the date there was a drop in RTA's but surely this is not unexpected as we were in the lock down and traffic flows were massively reduced.

This is only the Forestry England data. How many boar are culled by private guns in the the Fod?

If the above data is correct then in 2019/20 85.5% of the estimate boar population was culled by FE staff! . So 14.5% left to be targeted by other shooter. Clearly the population estimate has to be incorrect as such cull levels would be unsustainable/unachievable and boar would be extinct. Perhaps some of the SD members who advertise boar shooting in the Fod may like to input the numbers of boar they cull.

It appears that surveys were at night with thermal but the methodology is not stated. From my walk with a thermal in the Dean target acquisition is very difficult due the heavy woodland/timber and undergrowth and the terrain is highly undulating and only a small percentage is visible at any time. I could see things my shorter colleagues could not see and I have had 6 years experience of thermal use 4/5 times a week. Once I got accustomed to what boar looked like through the thermal they were everywhere.

Also you need to look at the deer survey figures: when we went on the Fod railway my partner was spotting fallow everywhere. How on earth they can estimate the Munty population is beyond me.

Further food for thought:

Average litter sizes in the Dean are between 6 and 10 piglets, nearly twice that of their continental cousins. With few natural predators, plenty of food and shelter early survival rates for the piglets is thought to be high. Research also shows that some of the Dean’s wild boar reach sexual maturity in their first year.

How does this statement correlate with the survey data?

Some more data to look at:

Useful links
Deer Initiative’s best practice guide ‘Wild Boar Legislation’ www.wild-boar.org.uk
University of Worcester ‘The Social Aspects of Wild Boar in the Forest of Dean’
Distance sampling / thermal image survey reportsfrom Forest Research.

Annual Census Reports​

Feral Wild Boar Census 2018​

Feral Wild Boar Deer Dean Census 2018 (PDF 338.47 KB)

Feral Wild Boar Census 2019​

Feral Wild Boar Deer Dean Census 2019 (PDF 408.08 KB)

Feral Wild Boar Census 2021​

Feral Wild Boar Census 2021 (PDF 429.02 KB)
Can

Regards

D

I think you are blinding yourself with pseudo science and precious little knowledge of statistics.

Yep, lets say there are, at a given moment, only 400 in the population.

Yet they breed, approx. 50:50 ratio to male vs. female piglets. Who can apparently sprog within their first year. Even, in exceptional circumstances, littering ten or more each time. Oooh could be as many as 200 sows x10= 1,000 per year female piglets to be taken out. The male ones can't self-replicate,, but lets add them in anyway, totalling 2000. You don't actually need that many male ones to fertilise the females. Though how you can tell them apart at that stage I would not know.

Then make the assumption that all live long, and prosper to a ripe old age, never die of natural causes, and there is an infinite food supply, seems like exponential growth is inevitable.

That's not how it really works though, is it. Nor do I think that "recreational or guided or syndicate" stalkers are particularly interested in shooting piglets, as part of a management plan. If anything, wanting to leave them to grow up a bit, to give more sport. And the more the merrier, from their perspective.

Hence why the professionals are having to do it instead.

As another has suggested, the actual numbers culled privately would make interesting reading. Ought to be possible to figure out something, because if properly done, each one ought to have been trichinella tested. But that's only mandatory for the ones being put into the food chain, not the ones only eaten by the hunter, family and friends.

If, and when ASF makes its way over here, and gets into the wild, expect an elimination cull. The Scots are already talking of that.

 

[thomas]

They do provide and publish accurate figures. It has always been stated that the aim is to reduce the population to 400 feral wild boar.
I think if the private shooters actually published their figures, they may scare themselves with the amount collectively culled in and around the FOD

That is the most sensible comment I have heard with regard to boar numbers / control in a very long time! From talking to my neighbours / local stalkers I can make a sensible guesstimate to the numbers shot in my immediate area, and the figures for the past few years have been ridiculous! I for one will not be too disappointed to see the numbers reduced and I congratulate the FC on their efforts. Bear in mind the nucleus of the population, escapee's / deliberate release was very small, if the FC foot is taken off the gas the numbers will soon escalate.

 

[timbrayford]

.
Who can apparently sprog within their first year. Even, in exceptional circumstances, littering ten or more each time. Oooh could be as many as 200 sows x10= 1,000 per year female piglets to be taken out. The male ones can't self-replicate,, but lets add them in anyway, totalling 2000. You don't actually need that many male ones to fertilise the females. Though how you can tell them apart at that stage I would not know.

I think that you might be confusing Wild Boar with modern hybrid domestic sows with that sort of productivity!

 

[Night òwl]

I think you are blinding yourself with pseudo science and precious little knowledge of statistics.

Yep, lets say there are, at a given moment, only 400 in the population.

Yet they breed, approx. 50:50 ratio to male vs. female piglets. Who can apparently sprog within their first year. Even, in exceptional circumstances, littering ten or more each time. Oooh could be as many as 200 sows x10= 1,000 per year female piglets to be taken out. The male ones can't self-replicate,, but lets add them in anyway, totalling 2000. You don't actually need that many male ones to fertilise the females. Though how you can tell them apart at that stage I would not know.

Then make the assumption that all live long, and prosper to a ripe old age, never die of natural causes, and there is an infinite food supply, seems like exponential growth is inevitable.

That's not how it really works though, is it. Nor do I think that "recreational or guided or syndicate" stalkers are particularly interested in shooting piglets, as part of a management plan. If anything, wanting to leave them to grow up a bit, to give more sport. And the more the merrier, from their perspective.

Hence why the professionals are having to do it instead.

As another has suggested, the actual numbers culled privately would make interesting reading. Ought to be possible to figure out something, because if properly done, each one ought to have been trichinella tested. But that's only mandatory for the ones being put into the food chain, not the ones only eaten by the hunter, family and friends.

If, and when ASF makes its way over here, and gets into the wild, expect an elimination cull. The Scots are already talking of that.

Sorry but the information is incorrect, mandatory testing is for ALL carcasses no matter who eats them , they must be tested before even being released into the chain irrelevant of who eats them , it clearly states that on the test paperwork

 

[Sharpie]

Sorry but the information is incorrect, mandatory testing is for ALL carcasses no matter who eats them , they must be tested before even being released into the chain irrelevant of who eats them , it clearly states that on the test paperwork

I don't think that I am incorrect, on this technical point. Unless I have been reading old information. AFAIK it is not yet mandatory for hunters etc. who might forgo the testing, providing it doesn't reach the public, though that would be foolhardy IMO.

I wonder what happens to some that get shot privately, perhaps by people who don't know the rules nor even show up prepared with a test kit..

See https://www.food.gov.uk/sites/default/files/media/document/trichinellatesting.pdf

Feral wild boar that have been shot by hunters in the UK and are
supplied direct to the consumers or to local retail establishments
should be tested. Although trichinae can be killed by thoroughly
cooking meat products it is essential we take steps to limit the risk
of infected meat reaching the consumer

...

Although the population of wild boar in the UK is small it is not
insignificant. As well as the risk from consumption of infected wild
boar meat there is a risk due to the interaction between these
animals and domestic pigs which includes reported cases of
interbreeding between domestic sows and wild boar. Infection
can only be contracted by consumption of undercooked infected
meat. As wild boar are potential sources of infection they must
be brought into the Trichinella monitoring system.

I think that you might be confusing Wild Boar with modern hybrid domestic sows with that sort of productivity!

I was of course making a most exaggerated point. That I suspect Cyres was misunderstanding the difference between estimate population, target population, cull achieved etc. It is perfectly obvious that to maintain a target population over the year, you are going to have to cull rather more, since they do breed, at whatever level of "efficiency" and frequency.

 

[Night òwl]

I don't think that I am incorrect, on this technical point. Unless I have been reading old information. AFAIK it is not yet mandatory for hunters etc. who might forgo the testing, providing it doesn't reach the public, though that would be foolhardy IMO.

I wonder what happens to some that get shot privately, perhaps by people who don't know the rules nor even show up prepared with a test kit..

See https://www.food.gov.uk/sites/default/files/media/document/trichinellatesting.pdf

Feral wild boar that have been shot by hunters in the UK and are
supplied direct to the consumers or to local retail establishments
should be tested. Although trichinae can be killed by thoroughly
cooking meat products it is essential we take steps to limit the risk
of infected meat reaching the consumer

...

Although the population of wild boar in the UK is small it is not
insignificant. As well as the risk from consumption of infected wild
boar meat there is a risk due to the interaction between these
animals and domestic pigs which includes reported cases of
interbreeding between domestic sows and wild boar. Infection
can only be contracted by consumption of undercooked infected
meat. As wild boar are potential sources of infection they must
be brought into the Trichinella monitoring system.

I was of course making a most exaggerated point. That I suspect Cyres was misunderstanding the difference between estimate population, target population, cull achieved etc. It is perfectly obvious that to maintain a target population over the year, you are going to have to cull rather more, since they do breed, at whatever level of "efficiency" and frequency.

As said it clearly states in bold and underlined on the paperwork ALL carcasses must be tested before being released, I fill enough in weekly for the last 10 years to no the forms off by heart

 

[Bavarianbrit]

A shotgun works on the piglets too. They grow up into breeders if not controlled.

 

[sikamalc]

I find it amazing that the FC along with various other conservation organisations are busting a gut to release Beaver, Lynx Sea Eagles etc back into the UK, and yet Wild Boar are considered to be eradicated where ever they are.
Going by some of the damage produced by some of the Beaver colonies, some landowners and farmers are not that happy about them. And yet they are welcomed. I find it a bit strange.

 

[Night òwl]

I find it amazing that the FC along with various other conservation organisations are busting a gut to release Beaver, Lynx Sea Eagles etc back into the UK, and yet Wild Boar are considered to be eradicated where ever they are.
Going by some of the damage produced by some of the Beaver colonies, some landowners and farmers are not that happy about them. And yet they are welcomed. I find it a bit strange.

Boar have produced a huge increase of tourism into the dean also , the FE seem to ignore that when it suits them