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We examined changes in plant species composition at Faville Prairie in southeastern Wisconsin, based on surveys in permanently-marked, 2 X 2 m quadrats in 1946-1948, 1976-1978 and 9005. Permanent quadrats were distributed across a wide soil moisture gradient. During settlement the site was never cultivated but was mowed for hay for several decades prior to 1946, and burned most years during the dormant season after 1946. Total species richness increased 47% between 1946-1948 and 2005, while species density per quadrat doubled. Only nine non-native species were present in 2005 and most were uncommon. Species density of habitat generalists increased nearly fourfold; moderate specialists increased 43%; and remnant specialists increased nearly twofold. Species density of endangered, threatened and special concern species (collectively conservation-dependent species) increased ninefold. Species density of C3 graminoids, C4 grasses, legumes, woody plants and forbs all increased through time. The majority of species density increases were attained by the 1976-1978 sampling period and remained high since. Elsewhere in Wisconsin, prairie habitat specialists have been declining. Our findings run counter to general trends throughout the state. It is likely that the change from annual mowing to annual prescribed burns accounts for the increases in species density., INTRODUCTION The tallgrass prairie has experienced more destruction and fragmentation than any other major ecosystem in North America (Samson and Knopf, 1994). Less than 0.1% of the original prairie within [...]

Eastern hemlock (Tsuga canadensis) was a major component of mesic forests in the Upper Great Lakes region, but presently persists in only a few locations. Many of these stands experience poor regeneration due to herbivory by white-tailed deer (Odocoileus virginianus), suggesting that hemlock will become progressively less common in these stands. We tested the hypothesis that balsam fir (Abies balsamea) facilitates establishment of eastern hemlock at 11 sites in northern Wisconsin. Hemlock saplings are three times as dense and twice as tall when growing within patches of balsam fir compared to growing outside such patches. Hemlock saplings growing outside balsam fir patches are also four times as likely to exhibit deer browsing damage as those growing inside. These results suggest that patches of balsam fir create a physical or visual barrier to deer and thus provide a refuge for hemlock saplings from white-tailed deer browsing. Because balsam fir saplings are much more abundant than hemlock in northern Wisconsin forests and establish on a wider range of sites, foresters could use patches of balsam fir to facilitate local hemlock establishment and so promote restoration of this important forest type., INTRODUCTION Eastern hemlock (Tsuga canadensis) is a long-lived, shade-tolerant conifer. In presettlement forests, it was a canopy dominant on mesic sites in the Upper Great Lakes states (Curtis, 1959). It [...]

Models based on the paleoecological record predict that animals in temperate regions will respond to global warming by migrating poleward to remain within their temperature tolerance ranges. The effect of global warming on invertebrates is of great concern because of their critical role in ecosystem structure and function. Migration poses a problem for many species because of their limited dispersal abilities. The life cycle of a typical temperate zone univoltine insect, Tenodera sinensis (Mantodea: Mantidae) is constrained by degree-days per season: too few prevent maturation before the killing frost in the autumn; too many allow egg hatch before a killing frost. We used field and laboratory observations on the life history and ecology, of this species to predict the effect of global warming on the regional distribution of this insect by the end of the next century. Based on the simplified, best-case, biological assumptions of our model, the geographical range of T. sinensis in eastern North America would be compressed toward the northern part of its present contiguous regional distribution. This and other univoltine temperate species with long maturation periods and low vagility could face regional extinction if global warming predictions are accurate., INTRODUCTION The effective concentration of heat-trapping trace gasses in the atmosphere is expected to double by the end of the next century (Schneider, 1993). As a result of this increase, [...]

Reference 1 Rezaei S, Mohammadi A, Bencini R, Rooney T, Naderi M. (2022) Identifying connectivity for two sympatric carnivores in human-dominated landscapes in central Iran. The affiliation for the last author is incorrect. [Extracted from the article]