Environmental changes such as global warming and habitat degradation are altering
the composition of animal and plant communities around the world. Understanding
these changes, and how to mitigate them requires understanding how species
interact as their populations vary in time and space. The emerging research
field of metacommunity biology attempts to integrate regional factors such
as landscape structure, with habitat heterogeneity and interaction between
species, to predict community composition and dynamics. Our research is aimed
at increasing the understanding of metacommunities by studying one particular
set of plants and animals in some detail. We study the species that interact
with the with Glanville fritillary butterfly in the Åland islands,
Finland. Over the 10 years that we have worked in this research system it
has become perhaps the best studied natural metacommunity worldwide.
The Glanville
fritillary butterfly metapopulation in Åland, Finland is
made up of local populations that are dynamic and differ in size, connectivity
and age . This is the context experienced by the parasitoids and hyperparasitoids
of the butterfly, and natural variation within this system can be used to test
predictions of (meta)community structure.
Food web around the butterfly Melitaea cinxia in Åland,
Finland
Food
chain length and contrasting spatial scales of parasitoid populations
One important prediction of metacommunity structure is that food chain
length decreases with habitat fragmentation. That is, the negative
affect of habitat
fragmentation increase with trophic level. We approach this idea several
ways using the plant-butterfly-parasitoid-hyperparasitoid food chains
in Åland.
van Nouhuys, S. 2009. Metapopulation Ecology. 2009 PDF Encyclopedia of Life Sciences (ELS). John Wiley & Sons, Ltd: Chichester. DOI: 10.1002/9780470015902.a0021905
van
Nouhuys, S. & Hanski, I.2002. PDF Multitrophic interactions in
space: metacommunity dynamics in fragmented landscapes. In Multitrophic
level interactions (T. Tscharntke & B. A. Hawkins eds.) Cambridge University
Press. pp. 124-147
Tscharntke, T., R. Bommarco, Y. Clough, T. Crist, D. Kleijn,
T. Rand, J. Tylianakis, S. van Nouhuys, S.Vidal 2007. PDF
Conservation
biological control and enemy diversity on a landscape scale..Biological Control,
43: 294-309
Trade-off between
local competitive ability and dispersal
Species that interact antagonistically
(competition, or predator-prey) may co-exist at a landscape scale if one
performs better locally, and the other
can easily disperse to habitat patches that have not yet been
exploited. The parasitoids H. horticola and C. melitaeaarum have been thought
to do
this (Lei and Hanski 1998). However, with further research it
turns out that H. horticola is the superior local competitor and is more
dispersive than
C. melitaearum. Instead of coexisting by a mechanism that depends
on both local and landscapee scale processes, the two species persist because
at
a local scale enough hosts are left unparasitized by H. hortcola that C. melitaearum gets by as a fugitive.
van
Nouhuys, S. and Punju, E. Coexistence
of competing parasitoids: which is the fugitive and where
does it hide? 2010 Oikos,119: 61-70 pdf
Food
chain length and contrasting spatial scales of parasitoid populations
One important
prediction of metacommunity structure is that food chain length decreases
with habitat fragmentation. That is, the negative affect
of habitat fragmentation increase with trophic level. We approach this idea
several ways using the plant-butterfly-parasitoid-hyperparasitoid food chains
in Åland.
Indirect interactions in the metacommunity
Species interact indirectly through shared enemies (apparent
competition), or through intermediate
species, such as an herbivore that is experienced
by both its food plants and its parasitoids (Multitrophic
interactions).
These
indirect interactions vary spatially, and can
influence the large scale population dynamics
of species and community structure.
van Nouhuys, S. & Kraft, T. S.van Nouhuys, S. & Kraft, T. S. 2012 Indirect interaction between butterflies meditated by a shared pupal parasitoid,
Population Ecology, in presspdf
van
Nouhuys, S. & I. Hanski 2000.
Apparent competition between parasitoids mediated by a shared hyperparasitoid.
Ecology Letters, 3: 82-84 PDF
van
Nouhuys, S. & I. Hanski 2002. Multitrophic interactions
in space: metacommunity dynamics in fragmented landscapes. In
Multitrophic level interactions (T. Tscharntke & B. A. Hawkins
eds.) Cambridge University Press. pp. 124-147 PDF
