"LAND: Partial migration of red deer and tick distribution at the altitudinal colonization border" (2011-2014; Pr. nr. 203786/S30). NFR-"Miljø 2015" program.

We propose to establish a multidisciplinary project to understand the
functional significance of red deer migration for an invasive species, the
tick, and vice versa at the altitudinal colonization border. The red deer are
currently regarded a keystone herbivore along the west coast of Norway.
Alongside this increase in deer density, it is a common perception that the
ticks increase in abundance and distribution. The role of animal space use
for tick distribution are less well understood. Seasonal migration by red deer
may potentially play a key role for tick distribution. Equally true, the role of
parasites for partial migration pattern in large herbivores have been largely
ignored. Ticks can carry and transmit agents of human (Borrelia spp.) and
animal disease (Anaplasma spp.), and understanding the role of red deer
density and space use for tick density and disease prevalence can provide
a key to mitigation efforts. We aim to accomplish such an understanding
by a hierarchical, nested sampling design facilitated by the access to a
large number of GPS-marked individuals of red deer (>200) with known
migration tactics. This will allow us to (WP1) quantify the distribution of ticks
in landscapes along the west coast of Norway relative to migration, local
density, and fine-scale space use of red deer as well as relative to habitat.
We hypothesize that spring migration by red deer may allow (re)colonization
of higher altitude areas, for which ticks are not able to persist either year
round or in specific harsh years. In WP2, we estimate tick load from ears of
GPS-marked animals with known migration tactics and body mass, enabling
a study of the relationship between tick load and migratory behavior and
performance. In WP3, we link disease in ticks to migratory behavior and
performance of red deer. This will give important insight into distribution of
ticks and a potential role of red deer to serve as vector of ticks and their
diseases by seasonal migration.
Kim Magnus Bærum