The global properties of the classical three-dimensional Lotka-Volterra two prey-one predator and one prey-two predator systems, under the assumption that competition can be neglected, are analysed with the direct Lyapunov method. It is shown that, except for a pathological case, one species is always driven to extinction, and the system behaves asymptotically as a two-dimensional predator-prey...

Declining predator diversity may drastically affect the biomass and productivity of herbivores and plants. Understanding how changes in predator diversity can propagate through food webs to alter ecosystem function is one of the most challenging ecological research topics today. We studied the effects of predator removal in a simple natural food web in the Sierra Nevada mountains of California ...

Oswald J. Schmitz* and Lauge Sokol-Hessner School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven, Connecticut, 06511 U.S.A. Department of Ecology and Evolutionary Biology, Yale University, 370 Prospect Street, New Haven, Connecticut, 06511 U.S.A. *Correspondence: E-mail: [email protected] Abstract Theory in community ecology often assumes that preda...

After becoming extinct approximately 250 years ago in the Palatinate Forest, first Eurasian lynx (Lynx lynx) were reintroduced within this area 2016, with 20 following five years. We observed roe deer population Forest before (2016) and during (2017–2019) reintroduction by estimating evaluating hunting bag. The estimation based on distance sampling method was conducted ten defined transects an ...

intraguild predation (igp) occurs when one predator species consumes another predator species with whom it also competes for shared prey. we studied igp between different stages of hippodamia variegata and aphidoletes aphidimyza in absence and presence of extraguild prey (aphis gossypii) in petri dish arena. in the absence of extraguild prey all stages of h. variegata (larva1, 2, 3, 4, female a...

We manipulated predator densities and prey vulnerability to explore how interactions between two predators affect overall mortality of their shared prey. Our three-member study system included eastern oysters (Crassostrea virginica) and two of its major consumers: southern oyster drills (Stramonita haemastoma) and stone crabs (Menippe adina). Field experiments demonstrated that drills and crabs...

The behavior of a California isolate of the predaceous nematode, Odontopharynx longicaudata de Man, was studied in water agar culture. When feeding on an Acrobeloides sp. the predator completed its life cycle in 13 to 14 days at 25 C. Optimum temperature for reproduction of the predator was 25 C, few individuals survived at 10 C, and 30 C was lethal. Males were necessary for reproduction, and a...

The number of prey killed by diverse predator communities is determined by complementarity and interference among predators, and by traits of particular predator species. However, it is less clear how predators' nonconsumptive effects (NCEs) scale with increasing predator biodiversity. We examined NCEs exerted on Culex mosquitoes by a diverse community of aquatic predators. In the field, mosqui...

An interesting conundrum in biological control questions the efficiency of generalist predators as biological control agents. Theory suggests, generalist predators are poor agents for biological control, primarily due to mutual interference. However field evidence shows they are actually quite effective in regulating pest densities. In this work we provide a plausible answer to this paradox. We...