@article {JRN53950,
	title = {The landscape of fear: The missing link to understand top-down and bottom-up controls of prey abundance?},
	journal = {Ecology},
	volume = {5},
	year = {2014},
	month = {06/2014},
	pages = {1141-1152},
	chapter = {1141},
	abstract = {<p class="rtejustify">Identifying factors that may be responsible for affecting and possibly regulating the size of animal populations is a cornerstone in understanding population ecology.\&nbsp; The main factors that are thought to influence population size are either resources (bottom-up), predation, (top-down), or interspecific competition (called here- parallel influences).\&nbsp; However, studies of these effects have produced highly variable and often contradictory results regarding the relative strengths and influence of these factors. These varied results are often interpreted as indicating {\textquotedblleft}shifting control{\textquotedblright} among the three forces or existence of a complex, non-linear relationship among precipitation, resource availability, predation, and competition.\&nbsp; We argue here that these interpretations suggest a {\textquotedblleft}missing link{\textquotedblright} in our understanding of predator-prey dynamics.\&nbsp; We explore whether the landscape of fear model can clarify the inconsistencies and help us understand the roles, extent, and possible interactions of top-down, bottom-up, and parallel factors on prey population abundance.\&nbsp; We propose various predictions derived from the landscape of fear model.\&nbsp; For a single species, we suggest that as the makeup of the landscape of fear changes from relatively safe to relatively risky, bottom up impacts switch from comparatively strong to weak as top-down impacts go from weak to strong.\&nbsp; For two or more species, interspecific competitive interactions produce various combinations of bottom-up, top-down, and parallel impacts depending on which competing species is superior and whether their landscapes of fear are shared or distinctive.\&nbsp; We contend that these predications successfully explain many of the complex and contradictory results of current research.\&nbsp; We end by testing some of these predictions based on long-term data for small mammals from the Chihuahuan Desert in the U.S. and M{\'e}xico.\&nbsp; We conclude that the landscape of fear model does provide reasonable explanations for many of the results found and should be tested further and that this model has the possibility of being the {\textquotedblleft}missing link{\textquotedblright} in understanding bottom-up, top-down and parallel effects on population dynamics.</p>
},
	keywords = {bottom-up, Chihuahuan Desert, Dipodomys merriami, Durango, fox abundance, landscape of fear, Mapimi Biosphere Reserve, Merriami Kangaroo rat, parallel control effects, patch dynamics, predation risk, species conservation and management, top-down control, United States and Mexico},
	doi = {10.1890/13-1083.1},
	url = {/files/bibliography/14-012.pdf},
	author = {John W. Laundre and Lucina Hern{\'a}ndez and Lopez Medina, Pete and A. Campanella and Lopez-Portilla, Jorge and Gonzales-Romero, Alberto and Grajales-Tam, Karina M and Burke, Anna M and Peg Gronemeyer and Dawn M. Browning}
}
@conference {50235,
	title = {Rodent density and the landscape of fear in the Chihuahuan Desert},
	booktitle = {93rd Ecological Society of America Annual Meeting},
	series = {93rd ESA Annual Meetings},
	year = {2008},
	month = {August 3-8, 2008},
	pages = {COS 118-8},
	abstract = {Small mammals in desert environments are important links in ecosystem energy flow, with their densities often effecting the abundance of their primarily predators.  Granivorous small mammals also affect seed dispersal and can shape vegetation characteristics.  Consequently, factors affecting small mammal abundance are important in understanding community and ecosystem structure and dynamics.  Small mammal abundance has been attributed to levels of precipitation/primary productivity (bottom up) and/or removal by predation (top down).  However, small mammal abundance can vary greatly over the landscape in relatively short (< 5 km) distances.  Similarities in precipitation amounts and predator abundance on this small scale do not explain this within-landscape variation in abundance.  However, on this scale, habitat heterogeneity can be high. Under the landscape of fear model, such habitat heterogeneity can result in proportionally different amounts of safe vs risky habitat and consequently, predation risk among adjacent areas.  We predicted that density of small mammals in an area is inversely related to the proportion of risky habitat/level of predation risk of an area.  We tested this prediction with kangaroo rats (Dipodomys spp.) in two geographically separate areas of the Chihuahaun Desert:  Mapimi Biosphere reserve in Durango Mexico and the Jornada Experimental range in New Mexico.  We measured giving up densities (GUDs) in 8 distinct areas of similar shrub/grass habitat with different densities of kangaroo rats. GUD{\textquoteright}s were measured with commercial 50 x30 x 10 cm aluminum buffet trays containing 3 kg of sand and 4 g of millet seed.  The specific prediction was that GUDs would be inversely related to kangaroo rat densities.},
	keywords = {abstract, Chihuahuan Desert, desnity, rodent},
	author = {John W. Laundre and Lucina Hern{\'a}ndez and A. Campanella and D. K. James}
}
