Capercaillie Emergency Plan 2025 - 2030 - Flipbook - Page 47
Monitoring morbidity and mortality
Following a study commissioned by the Carrbridge Capercaillie Group as
part of the Cairngorms Capercaillie Project, scope now exists to investigate
infectious disease threats from gastrointestinal parasites as a potential
cause of morbidity and mortality.
The Carrbridge Capercaillie Group commissioned RZSS to assess the feasibility
of monitoring parasite egg counts in capercaillie droppings whilst evidence
shows that parasitism significantly impacts Tetraonidae species and
contributes to morbidity, mortality, and population declines. This is welldocumented in red grouse, where parasites lead to decreased growth rates,
smaller clutch sizes, and higher mortality.
In many wildlife species it is believed that parasites do little or no harm, unless
their hosts are otherwise compromised, for example by malnutrition, stress or
adverse weather and climate change. If compromised by such factors,
parasitism can become a significant contributor to morbidity and mortality.
The pilot study by RZSS successfully demonstrated that non-invasive faecal
sample collection from wild capercaillie is feasible and provides results
comparable to those from European populations, including the detection of
potential pathogens.
To better understand the impact of gastrointestinal parasites on capercaillie,
further research is needed, including serial sampling of breeding areas to
examine parasite distribution and prevalence. Research into the parasitology of
other birds in capercaillie areas is also recommended, particularly pheasant as
they are likely reservoirs of parasites that can significantly impact health and
may be a potential risk for capercaillie.
A program of infectious disease surveillance for capercaillie and sympatric
Galliformes could involve the collection of droppings to monitor parasite
presence and prevalence; the periodic health assessments of captured birds, if
opportunities arise; and prompt and thorough postmortem examinations of
deceased birds. Data collected can be used to guide management decisions and
inform any necessary interventions to mitigate disease impacts.
Tissue samples taken and biobanked for disease analysis would help to
increase the existing sample size of genetic material from Scottish populations
as recommended by RZSS as part of the genetic diversity research
commissioned by the Cairngorms Capercaillie Project. The study brought
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