Open PhD position in Parasitoid Metacommunity Ecology:click here
A central focus of community ecology
is to distinguish between structure due to ecological interactions such as
competition, predation and parasitism,
and structure due to chance or to extrinsic factors such as habitat fragmentation.
In a metacommunity differences among local communities can be used to
disentangle
these processes,
and to assess the role of dispersal among patches in determining community
dynamics.
The Glanville
fritillary butterfly metapopulation in Åland, Finland
is made up of local populations clustered into networks of populations
that are dynamic and differ in size, connectivity and age . This
is the context experienced by the parasitoids of M. cinxia,
and natural variation within this system can be used to test predictions
of (meta)community structure.
van
Nouhuys, S., Hanski, I. 2005
Metacommunities of butterflies and their parasitoids. In Metacommunities: Spatial
Dynamics
and
Ecological Communities (M. Leibold, R. Holt and M. Holyoak eds.). University
of Chicago Press. pp. 99-121PDF
Tscharntke, T., R. Bommarco, Y.
Clough, T. Crist, D. Kleijn, T. Rand, J. Tylianakis, S. van Nouhuys, S.Vidal
2007. Conservation biological control and enemy diversity on a landscape scale.(authors
alphabetical after Tscharntke).
Biological Control, 43: 294-309 PDF
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. & Hanski, I. 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
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? 2009 Oikos, in press pdf
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. & 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
The
Glanville fritillary butterfly (Melitaea cinxia) and the closely related Heath fritillary, M. athalia,
overlap
in distribution in Åland. Preliminary data
show that these two butterfly species support the same pupal parasitoid
species, but not in the
same proportion.
We will
conduct field experiments are measuring the extent and symmetry
of apparent competition between them. Based on the results of the
experiment and the overlap
in habitat use in Åland we will model this indirect effect
of the presence of M. athalia on M. cinxia.
Shaw, M. R, Stefanescu, C., van Nouhuys, S.
Parasitoids of European Butterflies in Ecology of Butterflies of Europe (eds.
J.
Settele, T. G. Shreeve, M. Konvicka & H.
Van Dyck) Cambridge University Press, in press.
van Nouhuys, S., Hanski, I. 2004.
Natural enemies of checkerspot butterflies. In On the Wings of Checkerspots:
A Model System for
Population
Biology (P. R. Ehrlich & I. Hanski, eds.) Oxford University Press,
pp. 161-180 PDF
Kuussaari,
M., van Nouhuys, S., Hellmann, J., Singer, M. C. 2004.
Checkerspot butterfly larval biology. In On the Wings of Checkerspots:
A Model System for
Population Biology (P. R. Ehrlich & I. Hanski, eds.) Oxford University
Press, pp. 138-160 PDF
Reudler
Talsma, J., Torri, K. van Nouhuys, S. 2008 Host plant use by the
Heath fritillary butterfly, Melitaea athalia: plant habitat,
species and chemistry. Arthropod-Plant Interactions, 2: 63-75 PDF
