Lemming - Finlande - 25 mai 2007

PhD student position (alternatively Post Doc) available at Section
of Ecology, Department of Biology, University of Turku; application
deadline 25.5.2007

TITLE: TROPHIC CASCADES AND HERBIVORE IMPACTS ON TUNDRA: FEEDBACKS ON
BIODIVERSITY AND CLIMATE; INSTRUCTOR: LAURI OKSANEN

Outlines of the project:

A lemming outbreak is coming on the mainland tundra of northernmost
Norway, allowing us to study whether lemmings are dynamically in the role
of predators of plants or in the role of prey of carnivorous mammals and
birds. In this context, we will also study whether the lemmings respond
to high population densities by "migrations" (long-range dispersal).

While the focus is ecological, the project has a clear evolutionary
dimension. If lemmings were regulated by predationlike other microtien
rodents, long range dispersal would be pointless and should not
occur. If, however, lemmings are adapted to harsh environements where
winter food is the limiting factor, emigration is the only chance
to escape starvation. Out hypothesis is thus that those lemmings,
which "jump the cliff" (leave crowded mountains) take their a chance;
suicide is committed by those which chicken. As for plants, there has
been long standing argument that strong herbivirory should select for
low edibility. We doubt this. When winter food runs out, herbivores
are not especially selective and can severely injure even maximally
unpalatable plants, favoring resilience (e.g. graminoids). The outbreak
will enable us to test this hypothesis, too. We know that woody plants
are inedible for lemmings, while graminoids are their delicassy. We will
test the inedibility h ypothesis by studying the response ow graminoids
and ericaceous dwarf shrubs to the outbreak.

As typical, the lemmings come on short notice. Therefore, the current
funding is improvised, sufficing for 8 months as a PhD project (PhD
stipendium 1255 EUR/month) or for 6 months as a post doc project
(stipendium 1600 EUR/ mo). Grant proposals for more sustained funding
are pending, but lemmings do not wait. The project will thus be started
already 1st July this summer. A detailed project description is found
on my homepage (http://users.utu.fi/lauoks/2007-herbivoryproject.doc)

The successful candidate is expected to start working in the project from
01.07.2007 and is expected to be prepared to do fieldwork on the tundra
periodically in all seasons. We will indeed work on other rodents and
their impacts, too, using e.g. experimental predator-free islands with
introduced gray-sided voles.

applications with CV and list of publications should be mailed to:
lauoks@utu.fi by 25.5. 2007. decision will be announced within a week.

Lauri Oksanen, Professor in Plant Ecology
Section of Ecology, Department of Biology
University of Turku
FI-20014 Turku, Finland

phone: +358-2-333 55 57
cell phone +358-40-77 33 710

Lauri Oksanen <lauoks@utu.fi>