HC Deb 23 March 2004 vol 419 cc684-93W
Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs if she will carry out an assessment to determine whether perturbation in badger populations can be eliminated or substantially reduced by improved badger culling programme design and execution. [157933]

Mr. Bradshaw

Research by the Central Science Laboratory and Oxford University suggests that culling operations may cause some spatial and demographic perturbation of badger populations. The amount of perturbation is a factor of the degree of culling, and the number of badgers surviving it. The more or, conversely, the less effective a badger culling programme is, the less the perturbation effect may be. Given the number of replicates that would be required at varying levels of culling efficiency and badger density, it would be difficult to design a study to quantify accurately the effects on the levels of perturbation that different culling programmes would have.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what progress has been made with the(a) recruitment and (b) retention of appropriately skilled staff for carrying out badger culling operations. [157943]

Mr. Bradshaw

Full staff complement in the Wildlife Unit (WLU) would have been achieved during December 2003, however due to the announcement on 4 November 2003 to suspend the reactive culling element of the Randomised Badger Culling Trial (RBCT), three recruited staff were not offered posts.

There are currently 21 occupied field staff posts that are no longer required for delivery of the remaining elements of the RBCT. At present, there is no proposal to make the surplus staff redundant.

The pattern of staff turnover within the WLU is not considered excessive, and retention is not seen as a current issue. The surplus staff as indicated above provides a substantial buffer against possible future loss of expertise.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs (1) what natural factors restrain growth in badger populations when(a) the size of the population is less than the theoretical carrying capacity of the environment that it occupies and (b) there are opportunities for migration; [157953]

(2)pursuant to the answer of 12 February 2004, Official Report, column 1559W, what regulatory mechanisms limit the size of wild badger population. [158416]

Mr. Bradshaw

Badger population growth is constrained by reproductive output, mortality and migration. These factors will influence the population growth rate whether the population is below, at, or above the environmental carrying capacity. There is no reason to suspect that opportunities for migration will ever be absent but migration rates do appear to be generally low in badger populations. Reproductive output is probably limited by the number of reproducing sows per social group and the average litter size per sow. Both of these factors appear to be governed by nutrition. Mortality is also largely governed by nutrition, but is also influenced by stochastic events, such as dry summers. However, since all British badger populations studied reproduce well below their theoretical maximum, reproductive output is considered to be the major limiting factor to population growth.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what powers of entry wildlife officers have in order to gain access to badger setts for the purpose of trapping and destroying badgers. [158015]

Mr. Bradshaw

Participation in the trial is voluntary in all the triplet areas. Defra Wildlife Unit staff have no powers of entry to carry out badger culling and are on land with the consent of land-owners.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs which organisation is responsible for issuing licences for the killing of badgers under section 10 of the Protection of Badgers Act 1992. [158342]

Mr. Bradshaw

The Department's National Wildlife Management Team is responsible for issuing these licences.

Contact details:

  • Wildlife Administration Unit
  • Defra
  • Burghill Road
  • Westbury-on-Trym
  • BRISTOL
  • BS106NJ
  • Telephone 0845 6014523 (local rate)
  • Fax 0845 6013438 (local rate)
  • E-mail enquiries.southwest@defra.gsi.gov.uk
  • Web site: www.defra.gov.uk/wildlife-countryside/vertebrates

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs to what extent badger colonies approaching or exceeding the natural carrying capacity of their immediate environment rely on artificial food sources to sustain population levels. [158357]

Mr. Bradshaw

Research conducted by the Central Science Laboratory (CSL) suggests that badgers are more likely to seek artificial food sources, such as cattle feed, on dry nights when earthworm availability is limited. Potentially, artificial food sources could decrease badger mortality during protracted periods of natural food shortage, thereby bolstering local numbers. Currently, however, there is no information on the extent to which the value of such foods may differ with respect to population size and carrying capacity. The importance of cattle feed in badger diets forms part of an ongoing Defra funded research project being carried out by CSL, which is due to report in December 2005.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what the population(a) density and (b) incidence of TB in badgers is in (i) Scotland and (ii) England. [158358]

Mr. Bradshaw

Population density varies widely on a regional scale throughout Scotland and England. In Scotland, large tracts of the uplands have no badgers, with local pockets of relatively high density. Overall, population density in Scotland is in the region of 0.2 badgers per km2. In England population density also varies in different areas, from very high (up to 30 badgers per km2) to low, with an average in the region of 1 to 2 badgers per km.

The current incidence of TB in the national badger population is not known.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs whether perturbation in badger populations results in(a) increased contact between disparate social groups and (b) greater incidence of fighting between rival males, with more opportunities for infection spread through wounds. [158360]

Mr. Bradshaw

Disruption of social groups is likely to lead to changes in the contact rates of badgers from different social groups. However, there is currently insufficient data to quantify such effects accurately. No analyses have been carried out on the extent of aggressive confrontations, and the potential for disease transmission via bite wounding, in relation to population perturbation.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what the effect is of low body weight arising from food shortage on the disease resistance of individual badgers. [158366]

Mr. Bradshaw

Poor nutrition has been linked to disease susceptibility in several studies of animal and human health. Currently, however, no data are available to link low body weight to disease resistance in badgers.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what the role is of suppurating wounds in TB affected badgers in the spread ofM. bovis to (a) other badgers and (b) cattle. [158367]

Mr. Bradshaw

M. bovis has been isolated from bite wounds on badgers, although whether these resulted from transmission by biting or haematogenous spread following another portal of entry is still unclear. Infected bite wounds could be sources of infection for other badgers, particularly where mutual grooming occurs. Suppurating wounds are also a potential source of environmental contamination with infectious bacilli. This could pose a risk of infection to cattle if deposited on pasture, stored feed or in troughs.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what is meant by the term 'super-excretor' in respect of a badger infected by TB; and whether badgers so described exhibit atypical behavioural characteristics. [158375]

Mr. Bradshaw

Badgers excretingM. bovis are potential sources of infection for other badgers, and cattle. The term 'super-excretor' is used for research purposes to identify a sub-group of infected badgers from which M. bovis has been isolated from several different clinical samples. These animals are thought to be in an advanced stage of disease progression, and survival analyses have shown that they exhibit a higher rate of mortality than uninfected animals. Research conducted by the Central Science Laboratory has identified behavioural differences between badgers excreting M. bovis and uninfected animals. Badgers excreting M. bovis had larger home ranges and were more likely to visit farm buildings.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what the typical cost of obtaining market authorisation for an animal vaccine is; how long the authorisation process takes; whether the typical cost can be used as a basis for estimating the cost of a market authorisation for any animal TB vaccine developed; and whether it is possible to use vaccines without their undergoing the full market authorisation process. [158001]

Mr. Bradshaw

Under European legislation marketing authorisations for veterinary medicinal products, including vaccines, may only be granted where scientific assessment of data supplied by the applicant demonstrates that the product meets statutory criteria of safety, quality and efficacy. The fee currently charged by the Veterinary Medicines Directorate (VMD) for processing an application for a UK marketing authorisation is between £1,480 and £21,210, depending on the type of application and the complexity of the assessment required. The fee for a novel veterinary vaccine, such as a TB vaccine, is likely to be at the upper end of this range.

European legislation requires applications for new marketing authorisations for veterinary medicinal products to be processed within 210 "clock" days of submission of a valid application. "Clock days" are calendar days, including weekends and holidays but excluding any period where further information is requested and awaited from the applicant. The time taken for applicants to respond to requests for further information is dependent upon a number of factors including the nature of the information requested and the priorities of the applicant. During such periods the authorisation procedure is frozen. Therefore, typically, the total time taken to determine an application for a marketing authorisation for a novel veterinary vaccine, such as a TB vaccine, could be approximately two years.

European legislation permits provisional marketing authorisations to be granted, in exceptional, objective and verifiable circumstances, without the need for a full data dossier. Such authorisations are only granted where safety has been established and are subject to specific conditions, such as the carrying out of further studies for efficacy.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what the regulatory processes which affect the size of wild deer populations are; and whether the Government intervene in the natural regulatory processes. [158002]

Mr. Bradshaw

Deer are affected by the same 'regulatory processes' as other wildlife. The availability of key resources, particularly food, is the single most important determinant of population size. Management by man and incidental mortality (especially road traffic accidents) also play a role in influencing deer numbers.

In England, the Government 'intervenes' in a number of different ways, but most importantly through setting the legal parameters for deer management. Forest Enterprise, the government agency responsible for managing the nation's forest estate, intervenes more directly and is actively involved in managing deer within its forests.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs how many cats infected with bovine TB have been reported to her Department in each of the last five years. [158007]

Mr. Bradshaw

The information requested is given in the following table.

Suspect TB cases in cats reported to Defra Number of suspect cases confirmed by isolation of M. bovis from clinical or pathological specimens at Veterinary Laboratories Agency
2003 8 2
2002 9 2
2001 0 0
2000 2 2
1999 Not known Not known

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of whether cattle exhibit the same level of discrimination in respect of choice of food contaminated by badger faeces when feeding from cattle troughs as when grazing on grassland. [158008]

Mr. Bradshaw

Work carried out by Bristol University found that cattle generally avoided pasture contaminated with badger faeces, but that high stocking densities resulted in more cattle feeding at contaminated sites. It is likely that cattle would exhibit a similar level of discrimination against food contaminated with faeces, whatever the means of provision, but may not be afforded this choice if food is limited. This may be the case where cattle set-stocking densities are too high at pasture, where cattle are grazed on grassland recently cut for silage or where contaminated feed is present within a feed trough.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs in how many of the Krebs proactive and reactive trial areas there were areas of land within the trial areas, or abutting on them, where wildlife officers were refused entry for the purpose of trapping or destroying badgers. [158016]

Mr. Bradshaw

All 20 proactive and reactive trial areas have within them areas of land where permission to cull has been withheld by the land-owner.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of the optimum area in which badger control measures should be taken relative to a TB infected farm. [158018]

Mr. Bradshaw

The Report of the Independent Scientific Review Group chaired by Sir John Krebs recommended the removal of all badgers from all social groups with territories including the breakdown farm (or reactor land). The Independent Scientific Group on Cattle TB (ISG) advised on the practical implementation of this, and the reactive treatment of the Randomised Badger Culling Trial was implemented according to a Standard Operating Procedure ratified by the ISG.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs whether TB in badgers is a significant population regulatory factor. [158020]

Mr. Bradshaw

Bovine TB does not appear to be a significant population regulatory factor in badgers in Britain. Research by the Central Science Laboratory identified that of 207 marked badgers found dead in the Woodchester Park study area between 1978 and 1993, 65 per cent. had died from road traffic accidents, 9 per cent. had been killed, 7 per cent. died from starvation, 11 per cent. died from unknown causes and 9 per cent. died from TB. Since badger populations in Britain breed at significantly below their maximum potential, even the proportion of total mortality attributable to road traffic accidents is unlikely to affect population regulation.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs whether material contaminated with the M. bovis bacilli deposited on silage by badgers and used for the feeding of cattle is considered to present a significant risk of infection to cattle. [158022]

Mr. Bradshaw

There is little evidence to support the hypothesis that silage contaminated with material containing "Mycobacterium bovis" derived from badgers represents a significant risk of infection to cattle. However, "M. bovis" may survive outside the body for varying lengths of time and, so, there is a theoretical risk from this source.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of whether the current and proposed TB testing regimes in low risk areas are sufficient to ensure that new foci of infection do not develop which would pose a risk of spread to wildlife. [158370]

Mr. Bradshaw

The proposed testing regime meets or exceeds the requirements of the EC Directive 64/432/EEC. But neither this nor the current regime can guarantee that new foci of infection do not occur.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what her best estimate is of the incidence of TB in cattle arising from(a) cattle-to-cattle spread and (b) the spread from a wildlife reservoir. [158378]

Mr. Bradshaw

Current, continuing, research is designed to inform the Government on the relative importance of cattle and badgers as vectors of the disease. At present it is not possible to give a valid estimate for either.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what the latest advice issued by her Department is concerning cattle biosecurity measures. [159067]

Mr. Bradshaw

In 2001, Defra published "Golden Rules for a Healthy Herd". This guidance sets out the most important rules for minimising the risk of introducing diseases onto farms. It applies to those purchasing and selling cattle.

In 2002, Defra developed a concise biosecurity guidance poster with a number of livestock farming and veterinary organisations. "Better Biosecurity Provides…" was sent to every livestock farm in England and is available on the Defra website at: http:// www.defra.gov.uk/animalh/biosecurity/farmguidance/biosecleaf.pdf

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what estimate she has made of the likely incidence of TB in the badger population in 2007. [159072]

Mr. Bradshaw

The current incidence of TB in the national badger population is not known, so it is not possible to predict the incidence for future years.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs how long after exposure to an infective dose of M. bovis bacilli a bovine animal becomes infectious; and what the typical duration of infectivity is. [159074]

Mr. Bradshaw

Published figures for the time from exposure to being infectious include 87 to 226 days after natural exposure in a United Kingdom study and up to seven years in an Australian study. The typical duration of infectivity is not known.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what reasons have been adduced for the relatively low density of badgers in the eastern counties of England. [159075]

Mr. Bradshaw

The relatively low densities of badgers in eastern counties (excluding the south-east) compared to western counties is thought in part to reflect the east-west divide in the rural landscape. The predominantly pastoral west is thought to provide more preferred habitat for badgers than the arable east of the country.

However, this does not entirely explain the differences. In East Anglia badger densities are lower than would be expected based on landscape alone1, and it is concluded that in these areas the low densities are the consequence of past 'persecution' of badgers, from which badgers have yet to recover2.

1Heydon, M.J., Reynolds, J.C. and Short, M.J. (2000) Variation in abundance of foxes (Vulpes vulpes) between three contrasting regions of Rural Britain, in relation to landscape and other variables. "Journal of Zoology", 251,253–264.

2Reason, P., Harris, S. and Cresswell, P. (1993) Estimating the impact of past persecution and habitat changes on the numbers of badgers Meles meles in Britain. Mammal Review. 23: 1–15.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs to what extent different(a) age groups and (b) sexes of badgers are more likely to be trapped than others. [159077]

Mr. Bradshaw

Research carried out by Oxford University and the Department's Central Science Laboratories suggested that the likelihood of badger capture using cage traps did not vary between the sexes but did vary significantly between adults and cubs. However, the direction of this age effect was not consistent between different study areas suggesting that other local factors were also important.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs whether there have been any significant differences between the pattern of TB lesions observed in badgers subject to post-mortem examination pre-2000 and those examined during and after 2000. [159078]

Mr. Bradshaw

Information about lesion distribution in badgers since the start of the randomised badger culling trial has not been available to Defra officials for analysis. This information is held on behalf of the Independent Scientific Group on Cattle TB.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what the ideal geological conditions are for a badger habitat; and whether there are conditions which(a) prevent and (b) deter colonisation by badgers. [159083]

Mr. Bradshaw

Badgers can exist in a wide variety of habitat types. They typically locate setts in sandy or chalky, well drained soil that is easy to excavate. Setts are also usually located on hillsides or otherwise sloping ground where drainage is good, and excavated soil is easy to clear from the sett entrance. However, badgers are also known to dig setts into flat ground where such optimal conditions are not available. Badgers are much less likely to dig setts in clay soil types that are less well drained and less easily dug. Given that setts are an important resource for badgers, it has been argued that the availability of suitable sett sites has a direct effect on the density of setts, and hence social group density.

For further information, see: T. J. Roper (1993) Badger setts as a limiting resource. In: "The badger" (ed. T. J. Hayden) Royal Irish Academy, Dublin. E. G. Neal and C. L. Cheeseman (1996) "Badgers". Clements, E. D., Neal, E. G. and Yalden, D. W. (1988) The national badger sett survey. "Mammal Review", 18,1–9.

Mr. Paterson

To ask the Secretary of State for Environment, Food and Rural Affairs what research has been conducted by her Department to determine whether badgers infected withM. bovis are capable of transmitting infection to cattle. [159108]

Mr. Bradshaw

Apart from the study by the Central Science Laboratory at Woodchester Park in which infected badgers have been identified as excretingM. bovis in faeces, urine, tracheal aspirates and suppurating skin lesions, there has been a study in which naturally infected badgers were housed with uninfected calves. Several of the calves developed sensitivity to the tuberculin skin test and were found to have TB lesions when subject to post mortem examination.

Mr. Gray

To ask the Secretary of State for Environment, Food and Rural Affairs how many carcasses of red deer have been examined by the State Veterinary Service in the last 10 years at the Baronsdown deer sanctuary; and how many were found to be infected with bovine tuberculosis. [160170]

Mr. Bradshaw

Defra does not provide disease statistics on individual premises, but does so on a parish basis.

Since 1998 there have been nine confirmed cases of "M. bovis" in red deer in the parish of Dulverton, which includes Baronsdown.

Defra does not have data on the number of carcases of red deer examined by the State Veterinary Service in Dulverton prior to 1998.

Mr. Gray

To ask the Secretary of State for Environment, Food and Rural Affairs what assessment her Department has made of(a) whether deer populations on the Baronsdown deer sanctuary are sustainable and (b) whether the deer are infected with bovine tuberculosis. [160171]

Mr. Bradshaw

The information is as follows:

  1. (a) The management of deer at the Baronsdown deer sanctuary should be addressed to the League Against Cruel Sports, as the management of wildlife on private land is primarily a matter for the relevant landowner and not the Government.
  2. (b) Defra does not provide disease statistics on individual holdings. The deer on the Baronsdown sanctuary are wild and free to move.

The parish of Dulverton includes Baronsdown and other holdings. Since 1998 there have been nine confirmed cases of "M. bovis" in red deer in the parish of Dulverton.