09/05/2021
Report Highlights the Importance of
Data Led and Best Practice
Deer Management in Ireland
report in the peer-reviewed sclenHfic
Davis. The findings af a study undertaken by the
Microbial Genomics. titled
Department of Agriculture. Food and the
q»
"Mycobacterlum botts genomics reveals
Marine (DAFM) into the presence of bTB in wild
transmission of infection between cattle and
deer and cattle in Co Wicklow. a hot soot for
deer in Ireland" by Crispell et al..
bTB. were published in 2018 and showed the
Control af bovine tuberculosis (bTB). in the
presence of five strains of Mvcobacterium
Republic of Ireland costs €84millian each year
Davis in the study area. which . Crispell et al.'s
and has significant financial consequences for
study alfa highlights cattle and deer share
farming families. The repart evaluates if deer
some of these strains of Mvcobacterium bovis.
olav a role in the spread of bTB to cattle.
James Q'Keeffe. SVI. Head. DAFMs Wildlife Unit
Commenting on the repart. a spokesperson I k! : I d . ! 1 : 1 kFI ! said regarding the DAFM study "this
for the Irish Deer Commission said "while deer '
does not inform us about the directian of
like many other wildlife species are susceptible to TB at low levels, spread of disease, and cannot be used to draw anv conclusion
the report highlights that gated deer management can help aboutwhich species may be infecting which otherspecies."
reduce the spread of potentially infected wild deer by carrying
out informed data led culls annually to reduce wild deer numbers Sliqo and Co Kerry show no presence of bTB in deer tested. These
and maintain them at sustainable levels. Also. goad deer findings suggest there is na correlation between the presence of
management ensures we do not delve deer into new areas by bTB in cattle and the presence of deer. Similar findings can bo
over-culling or sustained increased hunting pressure."
Other studies undertaken by DAFM in catHe bTB hotspats in Co
taken from Scotland. despite an estimated deer papulatian of
It is understated deer can act as a spill over host for the infection over 800,000 wild deu, the county has been officially bTB free
where high deer densities are present. however there is no clear since September 2009.
evidence to show deer are a source of infection for cattle.
A recommendation to the Minister of Agriculture and the
The Microbial Genomics paper by Crispell et al. reports Mat the Minister of Ai'ts. Heritage and Gaeltacht in 201 5 by the Irish Deer
range and density of wild deer populaHons in Ireland is increasing. Management Forum. Data Sub-committee (representatives of
This statement is based on two published papers,
[i) A study on the 2008 national disMbutions and ranges of wild approxred by the Minister for Agriculture. Food & the Marine and
deer species present on the igand of Ireland published in 201 I in the Minister for Arts. Heritage. the Gaeltacht & Rural Affairs)
the scientific peer-reviewed journal, Mammal Review. by Carden confirmed "that there is na evidence to link Bovine TB incidence
ot al. . While new results based an 201 9 wild deer data is currently in deer in Ireland or the UK to Bovine TB outbreaks or oersbtence
being analysed by the irish Deer Commission. the 2008 data is very in cattle herds."
much out of date and should not be used.
stakeholder interests nominated by their respectNe groupings and
In 2018. Dr Elin Ryan, Chief Veterinary Inspector at the DAFM
[ii) A different study pub]]shed in the peer-reviewed said there is "no evidence of ]ink between wi]d deer and the
Scandinavian Journal of Forest Research. by Liu et al. in 2018. spread of TB." No study to date has showed the directionality of
titled "What factors affect national-scale deer population bTB transmission from wild deer to cattle for badger) or vice-a-
dynamics in the Republic of Ireland+". where the authors versa. Further research is required to elucidate transmission
modelled deer papulatian numbers based an the assumed the directionality within a potential multi-host system and certainly the
hardest rate data (NPWS cull returns from deer hunters) for each integration of genomics into routine bTB surveillance. as Crispell
deer species reflected the changing deer populations tor that et al. suggest. is a welcomed next step in further studies.
The many statements by academic and other experts in this
hunters occur at an equal rate across all counties that is constant area along with factual data available certainly call into question
claims deer are a source of infection to cattle. While the Microbial
The NPWS cull returns has limitations. inherent issues and cannot Genomics journal report contains several shalt comings. the
be independently xreritied. In the absence of a deer census it is discussion the report creates is to be welcomed. It is clear more
unknown if deer numbers are increasing ar decreasing in Ireland. research and ongoing suweillance is required in conjunction with
In Ireland bTB is caused by the bacterium. Mycabacterium best practice data led deer management.
species. They further assumed that the cull returns from deer
over time; in reality. this is nat the case.
