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Isle Royale National Park is generally considered a pristine ecosystem, but the island archipelago has a long history of human impacts that have altered the island's mammal communities through extirpations and introductions. The origin of red foxes (Vulpes Unlpes) on the islands are of particular interest given their ubiquity and uncertain colonization history. Red foxes were first reported on Isle Royale in 1925, shortly after the foundation of a small fox farm that began on Isle Royale in 1922. We sequenced two mitochondrial haplotypes from red fox scats collected on Isle Royale and compared them to haplotypes from the mainland surrounding Lake Superior, the predominant source of the island's other native mammals. Some Isle Royale foxes matched widespread haplotypes commonly found across Canada, bill over half of our samples matched haplotypes previously delected only in Newfoundland. While we cannot conclude a singular origin, we offer a working hypothesis red foxes on Isle Royale are derived from a combination of natural colonization and human introduction. Specifically, we propose native red foxes may be admixed with fur-farmed foxes from an introduction in the early 20th century., INTRODUCTION Isle Royale National Park--an island archipelago in Lake Superior--stands out as an ecosystem generally devoid of human influence (Radeloff el al, 2015). Indeed. Isle Royale has been identified as [...]

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2009.01494.x Byline: Michael P. Austin (1), Thomas M. Smith (2,3), Kimberley P. Van Niel (4), A. Bruce. Wellington (2,5) Keywords: carbon dioxide assimilation; environmental niche; functional type; generalized additive models (GAM); gradient experiment; light use efficiency; species distribution models (SDM); water use efficiency Abstract: Summary Our objectives were as follows: (i) to quantify the realized environmental niche of two co-occurring species and their differences and (ii) to examine whether differences in the species niches relate to differences in water and light use efficiency and growth responses to light and water. Statistical models of the environmental niches of two Eucalyptus species were derived from presence/absence records and from environmental variables (mean annual temperature, mean summer rainfall, mean summer daily radiation) and three factors (topographic position, lithology and a nutrient index) for 10 577 plots from south-eastern New South Wales, Australia. Generalized additive models (GAM) were fitted in a backwards stepwise procedure using Aikake's Information Criterion (AIC) for model selection. Seedlings were used in two experiments: (i) a water supply gradient with 20 treatments from 10 mL per day to 1000 mL per day and (ii) a light gradient with five treatments from 3% to 100% (full) sunlight. After controlling for lithology and nutrients, the principal differences in niche between species were as follows: (i) Eucalyptus mannifera was insensitive to mean summer daily radiation, (ii) it had a higher probability of occurrence in gullies and (iii) the two species differed in response shape and breadth of response to temperature, and temperature of maximum occurrence. Both species had a similar response to mean summer rainfall. Eucalyptus mannifera showed a monotonic increase in total biomass along the water supply gradient, consistently outperforming Eucalyptus dives, which showed little further increase above 440 mL per day. Consistent differences between species were found for leaf area, specific leaf area and allocation to leaves and stems. Diurnal measurements of conductance, transpiration, carbon dioxide assimilation and water use efficiency (WUE) showed differences between species along both the water and light gradients. Eucalyptus dives exhibits conservative responses to increasing resources and relatively higher WUE while E. mannifera has lower WUE. Synthesis. Species differences in ecophysiological strategies are consistent with their co-occurrence and with their realized environmental niche responses except for their temperature responses. The combination of statistical niche models and ecophysiological gradient experiments focuses attention on important unresolved environmental processes controlling distributions. Author Affiliation: (1)CSIRO Sustainable Ecosystems, GPO Box 284, Canberra City, ACT 2601, Australia (2)formerly of Research School of Biological Sciences, The Australian National University, Acton, ACT 2601, Australia (3)Department of Environmental Sciences, University of Virginia, PO Box 400123, Clark Hall, Charlottesville, VA 22904, USA (4)School of Earth and Environment M004, The University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia (5)6 Mirning Cres, Aranda, ACT 2614, Australia Article History: Received 6 October 2008; accepted 10 February 2009 Handling Editor: Frank Gilliam Article note: (*) Correspondence author. E-mail: mike.austin@csiro.au

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2007.01282.x Byline: ROY H. A. VAN GRUNSVEN (*[dagger]), WIM H. VAN DER PUTTEN ([double dagger]s.), T. MARTIJN BEZEMER ([double dagger]s.[paragraph]), WIL L. M. TAMIS (**), FRANK BERENDSE ([dagger]), ELMAR M. VEENENDAAL (1) Keywords: climate envelope; distribution; ecosystem functioning; enemy release; global change; invasive plants; pathogens; range shift; soil; thermophylic Abstract: Summary As a result of global warming, species may spread into previously cool regions. Species that disperse faster than their natural enemies may become released from top-down control. We investigated whether plants originating from southern Europe and recently established in north-western Europe experience less soil pathogen effects than native species. We selected three plant species originating from southern Europe that have immigrated into the Netherlands and three similar native Dutch species. All six plant species were grown in sterilized soils with a soil inoculum collected from the rhizospheres of field populations. As a control we grew a series of all six plant species with a sterilized rhizosphere inoculum. We harvested the plants, added the conditioned soil to sterilized soil and grew a second generation of all six plant species in order to test for each plant pair feedback effects from the conditioned soil communities to conspecifics and heterospecifics. The effect of the soil community is dependent on plant species, and is dependent on soil fertility in only one of the three pairs. Soil conditioning caused less biomass reduction to exotic plant species than to native species, suggesting that exotic immigrants are less exposed to soil pathogens than similar native plant species. Our results suggest that plant species that expand their range as a result of climate change may become released from soil pathogenic activity. Whether the exotics are released from soil pathogens, or whether they experience enhanced benefit from mutualistic symbionts remains to be studied. We conclude that range expansion may result in enemy release patterns that are similar to artificially introduced invasive exotic plant species. The escape from enemies through range shifts changes key biotic interactions and complicates predictions of future distribution and dominance. Author Affiliation: ([dagger])Nature Conservation and Plant Ecology Group, Wageningen University and Research Centre, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands, ([double dagger])Netherlands Institute of Ecology (NIOO-KNAW), Centre for Terrestrial Ecology, Heteren, The Netherlands, (s.)Laboratory of Nematology, Wageningen University and Research Centre, PO Box 8123, 6700 ES Wageningen, The Netherlands, (s.)Laboratory of Entomology, Wageningen University and Research Centre, PO Box 8031, 6700 EH Wageningen,The Netherlands, (**)Nationaal Herbarium Nederland/Leiden University Branch, PO Box 9514, 2300 RA Leiden, The Netherlands Article History: Received 24 January 2007; accepted 13 June 2007Handling Editor: Marcel van der Heijden Article note: (*) Author to whom correspondence should be addresed: Roy H. A. van Grunsven. Tel.: +31 317 483659. Fax: +31 317 419000. E-mail: royvangrunsven@gmail.com.

Glomalin is an abundant soil glycoprotein that could sequester substantial amounts of C and N on a global scale. Nevertheless, major controls over the distribution of this compound in ecosystems are little understood. We reviewed shifts in the production, decomposition, and standing stocks of soil glomalin in response to arbuscular mycorrhizal (AM) communities, plant dynamics, inorganic resources (e.g., N, P, and atmospheric C[O.sub.2]), and land use regimes. We also conducted a literature survey of glomalin concentrations from 22 ecosystems to test for relationships between standing stocks of glomalin and net primary productivity (NPP) and AM abundance. Globally, glomalin stocks were positively correlated with NPP but not with AM abundance. Rates of NPP may impose an upper bound for C available to AM fungi for glomalin construction. Availability of C to AM fungi appears to consistently influence glomalin dynamics in individual studies as well. Glomalin stocks are often greater where AM host plants are more abundant or are more effective hosts for the fungi (implying that more C is allocated to the fungi). In addition, elevated C[O.sub.2] frequently increases glomalin concentrations in soil. Other inorganic resources and land use change produce inconsistent effects on glomalin stocks. Overall, glomalin dynamics appear to be linked to C dynamics, and this relationship may allow us to better predict the contribution of glomalin to ecosystem feedbacks on global change. Abbreviations: AM, arbuscular mycorrhizal; BRSP, Bradford reactive soil protein; EE-BRSP, easily extractible Bradford reactive soil protein; EE-IRSP, easily extractable immunoreactive soil protein; ELISA, enzyme-linked immunosorbent assay; IRSP, immunoreactive soil protein; NPP, net primary productivity.