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It has been hypothesized that climate warming will allow southern species to advance north and invade northern ecosystems. We review the changes in the Swedish mammal and bird community in boreal forest and alpine tundra since the nineteenth century, as well as suggested drivers of change. Observed changes include (1) range expansion and increased abundance in southern birds, ungulates, and carnivores; (2) range contraction and decline in northern birds and carnivores; and (3) abundance decline or periodically disrupted dynamics in cyclic populations of small and medium-sized mammals and birds. The first warm spell, 1930-1960, stands out as a period of substantial faunal change. However, in addition to climate warming, suggested drivers of change include land use and other anthropogenic factors. We hypothesize all these drivers interacted, primarily favoring southern generalists. Future research should aim to distinguish between effects of climate and land-use change in boreal and tundra ecosystems. [ABSTRACT FROM AUTHOR]

Camera traps are commonly used to study mammal ecology and they occasionally capture previously undocumented species interactions. The key deer ( Odocoileus virginianus clavium ) is an endangered endemic subspecies of the Florida Keys, where it exists with few predators. We obtained a camera trap sequence of 80 photos in which a key deer interacted with two northern raccoons ( Procyon lotor ). One of the raccoons groomed the deer’s face for ∼1 min. This interaction is peculiar and appears mutualistic because the deer was not concerned and willingly remained still throughout the physical contact. Although mutualistic relationships between deer and birds are common, we are unaware of any previously documented mesocarnivore-deer mutualisms. Key deer have evolved in the absence of mammalian predators and we hypothesize that they exhibit reduced vigilance or concern when encountering other species because of predator naivety. Key deer and raccoons are commonly associated with humans and urbanization and an alternative hypothesis is that the interactions are a consequence of heightened deer density, causing a greater probability of sustained interactions with the common mesocarnivores. [ABSTRACT FROM AUTHOR]

The article presents a study to show that the relative abundance of ungulates communities positively correlates with the number of exclusively utilized plant species. It mentions species used for the experiment, method and final observations. Graphs depicting phytomass and number of forage plant species and the ratio between parts of food resources utilized by ungulates are also presented.

Ungulates impact woody species' growth and abundance but little is understood about the comparative impacts of different ungulate species on forest expansion in savanna environments. Replacement of native herbivore guilds with livestock [i.e., beef cattle ( Bos taurus)] has been hypothesized as a factor facilitating trembling aspen ( Populus tremuloides Michx.) encroachment into grasslands of the Northern Great Plains. We used a controlled herbivory study in the Parklands of western Canada to compare the impact of native ungulates and cattle on aspen saplings. Native ungulate treatments included a mixed species guild and sequences of herbivory by different ungulates [bison ( Bison bison subsp. bison), elk ( Cervus elaphus) then deer ( Odocoileus hemionus); or deer, elk, then bison]. Herbivory treatments were replicated in three pastures, within which sets of 40 marked aspen saplings (<1.8 m) were tracked along permanent transects at 2-week intervals, and compared to a non-grazed aspen stand. Stems were assessed for mortality and incremental damage (herbivory, leader breakage, stem abrasion and trampling). Final mortality was greater with exposure to any type of herbivore, but remained similar between ungulate treatments. However, among all treatments, the growth of aspen was highest with exposure only to cattle. Herbivory of aspen was attributed primarily to elk within the native ungulate treatments, with other forms of physical damage, and ultimately sapling mortality, associated with exposure to bison. Overall, these results indicate that native ungulates, specifically elk and bison, have more negative impacts on aspen saplings and provide evidence that native and domestic ungulates can have different functional effects on woody plant dynamics in savanna ecosystems. [ABSTRACT FROM AUTHOR]

Prior to European influence, predation by Native Americans was the major factor limiting the numbers and distribution of ungulates in the Intermountain West. This hypothesis is based on analyses of (1) the efficiency of Native American predation, including cooperative hunting, use of dogs, food storage, use of nonungulate foods, and hunting methods; (2) optimal-foraging studies; (3) tribal territory boundary zones as prey reservoirs; (4) species ratios, and sex and age of aboriginal ungulate kills; (5) impact of European diseases on aboriginal populations; and (6) synergism between aboriginal and carnivore predation. Native Americans had no effective conservation practices, and the manner in which they harvested ungulates was the exact opposite of any predicted conservation strategy. Native Americans acted in ways that maximized their individual fitness regardless of the impact on the environment. For humans, conservation is seldom an evolutionarily stable strategy. By limiting ungulate numbers and purposefully modifying the vegetation with fire, Native Americans structured entire plant and animal communities. Because ecosystems with native peoples are entirely different than those lacking aboriginal populations, a 'hands-off' or 'natural regulation' approach by today's land managers will not duplicate the ecological conditions under which those ecosystems developed. The modern concept of wilderness as areas without human influence is a myth. North America was not a 'wilderness' waiting to be discovered, instead it was home to tens of millions of aboriginal peoples before European-introduced diseases decimated their numbers. [ABSTRACT FROM AUTHOR]