Mobbing behavior is an important and widespread antipredatory behavior. This is a well-known behavior especially in birds. There are many studies about mobbing in birds, and most of them use owls as a model of predato...Mobbing behavior is an important and widespread antipredatory behavior. This is a well-known behavior especially in birds. There are many studies about mobbing in birds, and most of them use owls as a model of predator. However it is not clear how mobbing works when a predator assume a role of a prey. In this paper we organize field observations, which were taken on records of mobbing behaviors performed by owls or by other animals against them. These observations were collected nearby four Brazilian cities in South-Eastern and Central Brazil: Joao Monlevade / MG, Sacramento / MG Baguari / MG and Cacu / GO. Events of mobbing behavior have always involved prey(s) and predator(s) thus, in this study we presents mobbing events which species of owl always were involved, and beside the owls, other animals like mammals or raptors. These records are important due to their infrequency and problems to be detected in natural field conditions. It is rare mobbing events when an owl assumes a role of a prey, and there are few studies that show the mobbing by the predator optics. The present data may contribute for elucidation of mobbing behavior intrinsic aspects.展开更多
In this paper, we discuss the behavior of a predator-prey model with disease in the prey with and without stochastic perturbation, respectively. First, we briefly give the dynamic of the deterministic system, by analy...In this paper, we discuss the behavior of a predator-prey model with disease in the prey with and without stochastic perturbation, respectively. First, we briefly give the dynamic of the deterministic system, by analyzing stabilities of its four equilibria. Then, we consider the asymptotic behavior of the stochastic system. By Lyapunov analysis methods, we show the stochastic stability and its long time behavior around the equi- librium of the deterministic system. We obtain there are similar properties between the stochastic system and its corresponding deterministic system, when white noise is small. But large white noise can make a unstable deterministic system to be stable.展开更多
The diffusive Leslie-Clower predator-prey model incorporating a prey refuge is recon- sidered here. Sufficient and necessary conditions which guarantee the predator and the prey species to be permanent are obtained, a...The diffusive Leslie-Clower predator-prey model incorporating a prey refuge is recon- sidered here. Sufficient and necessary conditions which guarantee the predator and the prey species to be permanent are obtained, and our results supplement earlier ones.展开更多
When an immobile prey has detected an immobile predator nearby, predation risk is greater when the predator is closer. Consequently, prey flee with shorter latency as standing distance (predator-prey distance when bo...When an immobile prey has detected an immobile predator nearby, predation risk is greater when the predator is closer. Consequently, prey flee with shorter latency as standing distance (predator-prey distance when both are still) decreases. Since it was first reported in 2009, this relationship has been confirmed in the few species studied. However, little is known about the functional relationship between standing distance and latency to flee (LF). We hypothesized that LF increases as standing distance increases at short distances, but reaches a plateau at longer distances where prey can escape reliably if attacked. We simulated immobile predators by moving slowly into positions near striped plateau lizards Sceloporus virgatus, stopping and then remaining immobile, and recording LF from the stopping time. LF increased from shorter to longer standing distances in a decelerating manner. The relationship was concave downward, and LF was indistinguishable among the longer standing distance groups. Latency to flee appears to reach a plateau or approach an asymptotic value as stand- ing distance increases. The effect size of standing distance was large, indicating that S. virgatus sensi- tively adjusts LF to the level of risk associated with standing distance. Relationships between risk assessment and theoretical zones associated with risk, its assessment by prey, and escape decisions are discussed. Effect sizes of standing distance were substantial to large in all studies to date, indicating that standing distance is an important predation risk factor when both predator and prey are immobile.展开更多
In this paper, we consider a modified Leslie-Clower predator prey model with Holling- type II schemes and mutual interference. By applying the comparison theorem of the differential equation and constructing a suitabl...In this paper, we consider a modified Leslie-Clower predator prey model with Holling- type II schemes and mutual interference. By applying the comparison theorem of the differential equation and constructing a suitable Lyapunov function, sufficient conditions which guarantee the permanence and existence of a unique globally attractive positive almost periodic solution of the system are obtained. Our results not only supplement but also improve some existing ones.展开更多
文摘Mobbing behavior is an important and widespread antipredatory behavior. This is a well-known behavior especially in birds. There are many studies about mobbing in birds, and most of them use owls as a model of predator. However it is not clear how mobbing works when a predator assume a role of a prey. In this paper we organize field observations, which were taken on records of mobbing behaviors performed by owls or by other animals against them. These observations were collected nearby four Brazilian cities in South-Eastern and Central Brazil: Joao Monlevade / MG, Sacramento / MG Baguari / MG and Cacu / GO. Events of mobbing behavior have always involved prey(s) and predator(s) thus, in this study we presents mobbing events which species of owl always were involved, and beside the owls, other animals like mammals or raptors. These records are important due to their infrequency and problems to be detected in natural field conditions. It is rare mobbing events when an owl assumes a role of a prey, and there are few studies that show the mobbing by the predator optics. The present data may contribute for elucidation of mobbing behavior intrinsic aspects.
文摘In this paper, we discuss the behavior of a predator-prey model with disease in the prey with and without stochastic perturbation, respectively. First, we briefly give the dynamic of the deterministic system, by analyzing stabilities of its four equilibria. Then, we consider the asymptotic behavior of the stochastic system. By Lyapunov analysis methods, we show the stochastic stability and its long time behavior around the equi- librium of the deterministic system. We obtain there are similar properties between the stochastic system and its corresponding deterministic system, when white noise is small. But large white noise can make a unstable deterministic system to be stable.
基金This work is supported by the Natural Science Foundation of China (11102041, 11201072, 10831005), the Natural Science Foundation of Fujian Province (2011J01002, 2012J01002), and the Foundation of Fujian Education Bureau (Jm2030).
文摘The diffusive Leslie-Clower predator-prey model incorporating a prey refuge is recon- sidered here. Sufficient and necessary conditions which guarantee the predator and the prey species to be permanent are obtained, and our results supplement earlier ones.
文摘When an immobile prey has detected an immobile predator nearby, predation risk is greater when the predator is closer. Consequently, prey flee with shorter latency as standing distance (predator-prey distance when both are still) decreases. Since it was first reported in 2009, this relationship has been confirmed in the few species studied. However, little is known about the functional relationship between standing distance and latency to flee (LF). We hypothesized that LF increases as standing distance increases at short distances, but reaches a plateau at longer distances where prey can escape reliably if attacked. We simulated immobile predators by moving slowly into positions near striped plateau lizards Sceloporus virgatus, stopping and then remaining immobile, and recording LF from the stopping time. LF increased from shorter to longer standing distances in a decelerating manner. The relationship was concave downward, and LF was indistinguishable among the longer standing distance groups. Latency to flee appears to reach a plateau or approach an asymptotic value as stand- ing distance increases. The effect size of standing distance was large, indicating that S. virgatus sensi- tively adjusts LF to the level of risk associated with standing distance. Relationships between risk assessment and theoretical zones associated with risk, its assessment by prey, and escape decisions are discussed. Effect sizes of standing distance were substantial to large in all studies to date, indicating that standing distance is an important predation risk factor when both predator and prey are immobile.
文摘In this paper, we consider a modified Leslie-Clower predator prey model with Holling- type II schemes and mutual interference. By applying the comparison theorem of the differential equation and constructing a suitable Lyapunov function, sufficient conditions which guarantee the permanence and existence of a unique globally attractive positive almost periodic solution of the system are obtained. Our results not only supplement but also improve some existing ones.