211
They also make it possible to look at the spatial dynamics of the population and the
dispersal of individuals and, in certain cases, to infer reproductive success where it
could not been proven with other methods.
DNA-Data and Wolf Monitoring: A Case Study
The genetic situation of the wolf population in Scandinavia is an important
issue for the management of the species in Sweden. The population is inbred
and in great need of immigrating wolves from Finland and Russia, which
diversify the Scandinavian gene pool once they reproduce. Therefore, the collection of samples for DNA-analysis is an important part in the monitoring of
the wolf population in Sweden. However, DNA-information supports wolf
monitoring in several ways.
Samples are collected by professional wildlife trackers mostly during
snow tracking in winter, when they follow wolf packs, territorial pairs or, in
the reindeer herding area, even single animals. Samples are also taken at rendez-vous sites of family groups and in places where wolves have attacked
livestock. Trackers collect faeces, urine, blood, hair and saliva when they
encounter such material and send samples of it to Grimsö Research Station in
central Sweden, which is part of the Swedish University of Agricultural
Sciences. There, samples are sorted according to their priority; emergency
samples (e.g. samples from the reindeer herding area or from possible immigrants) are analysed within five working days, while the analysis of samples
of normal priority takes some weeks, and some low-priority samples are not
processed at all. Currently, more than 2000 wolf samples are collected and
about 1200 of them are analysed each year (e.g. Åkesson 2017). This figure
includes even tissue samples from wolves that are found dead or that have
been killed by anthropogenic causes (traffic, hunting, illegal killing). On average, about 50 dead wolves per year are examined by the National Veterinary
Institute in Sweden (e.g. Meijer and Ågren 2017).
In the first step of the analysis, DNA is extracted from the sample and purified with different methods, depending on the material provided in the sample. The next step is a polymerase chain reaction (PCR) process where the
DNA is amplified. In total, 30 autosomal microsatellites are looked at, plus
two markers for sex determination and five markers on mitochondrial
DNA. The different alleles of the microsatellite markers are then separated
and visualised by electrophoresis. Different genotypes (wolf individuals) are
defined by their individual variation of their alleles of the different markers.
Currently, a new method is being tested at the laboratory in Grimsö. Instead
of microsatellites, this method uses markers for single nucleotid polymorphism (SNP- markers). The method is supposed to be faster, cheaper and less
prone to analytical error. It has successfully been used for bears in Sweden
and is currently being developed for golden eagles as well.
(continued)
A Toolbox for Remotely Monitoring Large Carnivores in Sweden
They also make it possible to look at the spatial dynamics of the population and the
dispersal of individuals and, in certain cases, to infer reproductive success where it
could not been proven with other methods.
DNA-Data and Wolf Monitoring: A Case Study
The genetic situation of the wolf population in Scandinavia is an important
issue for the management of the species in Sweden. The population is inbred
and in great need of immigrating wolves from Finland and Russia, which
diversify the Scandinavian gene pool once they reproduce. Therefore, the collection of samples for DNA-analysis is an important part in the monitoring of
the wolf population in Sweden. However, DNA-information supports wolf
monitoring in several ways.
Samples are collected by professional wildlife trackers mostly during
snow tracking in winter, when they follow wolf packs, territorial pairs or, in
the reindeer herding area, even single animals. Samples are also taken at rendez-vous sites of family groups and in places where wolves have attacked
livestock. Trackers collect faeces, urine, blood, hair and saliva when they
encounter such material and send samples of it to Grimsö Research Station in
central Sweden, which is part of the Swedish University of Agricultural
Sciences. There, samples are sorted according to their priority; emergency
samples (e.g. samples from the reindeer herding area or from possible immigrants) are analysed within five working days, while the analysis of samples
of normal priority takes some weeks, and some low-priority samples are not
processed at all. Currently, more than 2000 wolf samples are collected and
about 1200 of them are analysed each year (e.g. Åkesson 2017). This figure
includes even tissue samples from wolves that are found dead or that have
been killed by anthropogenic causes (traffic, hunting, illegal killing). On average, about 50 dead wolves per year are examined by the National Veterinary
Institute in Sweden (e.g. Meijer and Ågren 2017).
In the first step of the analysis, DNA is extracted from the sample and purified with different methods, depending on the material provided in the sample. The next step is a polymerase chain reaction (PCR) process where the
DNA is amplified. In total, 30 autosomal microsatellites are looked at, plus
two markers for sex determination and five markers on mitochondrial
DNA. The different alleles of the microsatellite markers are then separated
and visualised by electrophoresis. Different genotypes (wolf individuals) are
defined by their individual variation of their alleles of the different markers.
Currently, a new method is being tested at the laboratory in Grimsö. Instead
of microsatellites, this method uses markers for single nucleotid polymorphism (SNP- markers). The method is supposed to be faster, cheaper and less
prone to analytical error. It has successfully been used for bears in Sweden
and is currently being developed for golden eagles as well.
(continued)
A Toolbox for Remotely Monitoring Large Carnivores in Sweden