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it is determined if the species occurs regularly or temporarily only. Among other
things, this information is important for the compensation system, where reindeer
herders get paid for the occurrence of large carnivores on their grazing grounds.
In central Sweden, where most of the Swedish wolves occur, snow tracking is an
important method for keeping track of the wolf population. Every winter, County
Administrations use this method to count the number of wolf packs and, if possible,
the number of individuals in each pack, and to determine if reproduction occurred
in any given territory the previous spring. The number of newly established territorial pairs is also determined (Liberg et al. 2012).
Nest and Den Surveys
Reproducing females are also the center of interest during wolverine surveys, which
last from March until the snow disappears in May to July, depending on the area.
Wolverines use dens in the snow to give birth to their young. Females can use the
same den site year after year, and good den sites may be used by consecutive females
under a long period of time. Wolverine surveys have been conducted since 1996 in
northern Sweden and the County Administrations have accumulated a good knowledge of important sites. This makes it possible to target these sites and to focus
survey activities there. The objectives of survey activities at natal dens are to find
out initially if the site is occupied and, if so, where the den is located, if there are
young in the den, and how many. At the same time, the female should not be disturbed. Snow tracking, direct observation from a distance, collection of samples for
DNA-analysis and automatic cameras are used at den sites to accomplish this
(Schneider 2006b). Sites where it is unclear if reproduction has occurred can even
be visited after snowmelt, when the wolverines have left, to look for signs of reproduction (juvenile hair, bite marks, prey remains, well-used trails etc.). Often, helicopters are used to effectively reach these usually remote places.
Even more so than wolverines, golden eagles can use the same place year after
year for rearing their young. Sites can be used by eagles for several decades and
ornithologists accumulate knowledge of where nests are, how often they are used,
and what quality a given site has. Each territory, in some cases with multiple nest
sites, of golden eagles has to be visited every year to find out if birds are present, if
they breed, and if breeding is successful, i.e. if the young survive until they leave the
nest (Ekenstedt and Schneider 2008). Survey activities include direct observation of
displaying birds from a distance in the beginning of the breeding season, closerrange nest observation during the season, as well as banding of young eagles and
taking samples for DNA-analysis at the end of the season. In remote areas in northern Sweden, helicopters can be used as an effective means to survey known eagle
territories. Several nests can be visited within a single day and the view from above
renders information about the number and age of the young.
A Toolbox for Remotely Monitoring Large Carnivores in Sweden
it is determined if the species occurs regularly or temporarily only. Among other
things, this information is important for the compensation system, where reindeer
herders get paid for the occurrence of large carnivores on their grazing grounds.
In central Sweden, where most of the Swedish wolves occur, snow tracking is an
important method for keeping track of the wolf population. Every winter, County
Administrations use this method to count the number of wolf packs and, if possible,
the number of individuals in each pack, and to determine if reproduction occurred
in any given territory the previous spring. The number of newly established territorial pairs is also determined (Liberg et al. 2012).
Nest and Den Surveys
Reproducing females are also the center of interest during wolverine surveys, which
last from March until the snow disappears in May to July, depending on the area.
Wolverines use dens in the snow to give birth to their young. Females can use the
same den site year after year, and good den sites may be used by consecutive females
under a long period of time. Wolverine surveys have been conducted since 1996 in
northern Sweden and the County Administrations have accumulated a good knowledge of important sites. This makes it possible to target these sites and to focus
survey activities there. The objectives of survey activities at natal dens are to find
out initially if the site is occupied and, if so, where the den is located, if there are
young in the den, and how many. At the same time, the female should not be disturbed. Snow tracking, direct observation from a distance, collection of samples for
DNA-analysis and automatic cameras are used at den sites to accomplish this
(Schneider 2006b). Sites where it is unclear if reproduction has occurred can even
be visited after snowmelt, when the wolverines have left, to look for signs of reproduction (juvenile hair, bite marks, prey remains, well-used trails etc.). Often, helicopters are used to effectively reach these usually remote places.
Even more so than wolverines, golden eagles can use the same place year after
year for rearing their young. Sites can be used by eagles for several decades and
ornithologists accumulate knowledge of where nests are, how often they are used,
and what quality a given site has. Each territory, in some cases with multiple nest
sites, of golden eagles has to be visited every year to find out if birds are present, if
they breed, and if breeding is successful, i.e. if the young survive until they leave the
nest (Ekenstedt and Schneider 2008). Survey activities include direct observation of
displaying birds from a distance in the beginning of the breeding season, closerrange nest observation during the season, as well as banding of young eagles and
taking samples for DNA-analysis at the end of the season. In remote areas in northern Sweden, helicopters can be used as an effective means to survey known eagle
territories. Several nests can be visited within a single day and the view from above
renders information about the number and age of the young.
A Toolbox for Remotely Monitoring Large Carnivores in Sweden