Here, we demonstrate a cascade of ecological events that were triggered by the local extinction of grizzly bears ( Ursus arctos) and wolves (Canis lupus) from the southern Greater Yellowstone Ecosystem. Fish predation had an important moderating effect on zebra mussel demography in Pool 8. Source: Estes et al. To predict future impacts, whether overt or subtle, of past management, and to restore biodiversity, more must be known about ecological interactions, including the role of large carnivores. Sea urchin biomass declined by 50% in the Aleutian Islands and by nearly 100% in southeast Alaska following the spread of sea otters into previously unoccupied habitats. Sea urchins, chitons and limpets, which had positive prey selection indices, were most abundant in the lower intertidal zones; barnacles and mussels, which had negative prey selection indices, were most abundant in the upper zones. “Late Pleistocene” is defined as approximately 11 ka for Africa, North and South America, and as 50 ka for Australia, because these times predate anthropogenic impacts on mammalian fauna. First, we developed a population viability analysis (PVA) to simulate a hypothetical population growth under different management scenarios. James A. Estes, 1 *John Terborgh, 2 Justin S. Brashares, 3 Mary E. Power, 4 Joel Berger, 5 William J. PVA models predicted that in the absence of an intense culling/hunting pressure, the population size will continue to steadily increase, which is consistent with the population growth observed during the last 20 years. The loss of top predators from ecosystems worldwide is one of the most pervasive impacts of humans on nature, but it remains unclear whether recovery of predator populations would reverse these impacts or not (Schmitz 2004; ... Research that elucidates predator size effects is particularly timely as climate change has been implicated in causing a shift toward smaller body size in many different species, but especially among ectotherms because their rate of metabolism scales directly with temperature (Genner et al. Avian species richness and nesting density varied inversely with moose abundance, and two riparian specialists, Gray Catbirds (Dumetella carolinensis) and MacGillivray's Warblers ( Oporornis tolmiei), were absent from Park riparian systems where moose densities were high. BC, represents among the most dramatic examples of trophic downgrading regionally, we hypothesized that more recent efforts to reduce deer density on the island have the potential to reverse the effects of trophic downgrading by initiating an increase in the richness, diversity, and cover of palatable plant species (‘trophic upgrading’). However, fundamental understanding of the interdependent relationship between static conditions and dynamic processes is still largely undeveloped. Such large-scale manipulations of a key element of most ecosystems offer unique opportunities to investigate how the loss of large carnivores affects communities, including the extent, if any, of interactions at different trophic levels. Les activités humaines sont la principale cause des changements globaux avec des conséquences néfastes sur l’ensemble de la biodiversité, aussi bien terrestre que marine. 1960;Paine 1980;Carpenter et al. Despite intersite variation in the abundance of kelps and herbivores, these analyses demonstrate that sea otter predation has a predictable and broadly generalizable influence on the structure of Alaskan kelp forests. Bond, Stephen R. Carpenter, Timot. Strong effects of predation by fishes on an invasive macroinvertebrate in a large floodplain river, Extinction of an Island Forest Avifauna by an Introduced Snake, Estimating the global conservation status of more than 15,000 Amazonian tree species, Distribution and abundance of tree species in swamp forests of Amazonian Ecuador, A Comparison of Tree Species Diversity in Two Upper Amazonian Forests, Dominance and Distribution of Tree Species in Upper Amazonian Terra Firme Forests. Download. Wolves were recently removed from the Cedar Creek Ecosystem Science Reserve (Minnesota, USA), such that consumptively mediated predator effects were negligible. 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