Generalist mammalian predators hunt for prey in different ways than raptors,often relying on ambush attack.Such differences in predator behavior can have profound effects on susceptibility of different species of prey...Generalist mammalian predators hunt for prey in different ways than raptors,often relying on ambush attack.Such differences in predator behavior can have profound effects on susceptibility of different species of prey to predation,but can also modify the behavior of prey.We investigated susceptibility of common birds to predation by domestic cats Felis catus,relying on an extensive data set on prey abundance and prey availability as determined by standardized bird counts.Susceptibility to cat predation for different species of birds was not significantly correlated with susceptibility to predation by sparrowhawk Accipiter nisus,but with susceptibility to goshawk Accipiter gentilis predation. Susceptibility to goshawk predation was independently predicted by susceptibility to cat and sparrowhawk predation.We cross-validated our estimate of susceptibilityto cat predation by showing that the frequency of birds with tail loss increased strongly with sus-ceptibility to cat predation.Male birds were disproportionately preyed upon,especially if havingsong posts low in the vegetation,and if having short flight distances when singing.Colonially breeding species were less susceptible to predation than solitary species.Bird species with high levels of innate immune defense against bacterial infections had high susceptibility to cat predation.These findings suggest that predation by cats has been an important selection pressure affecting anti-predation behavior,sexual display and immune function in common birds.展开更多
The endemic fauna of New Zealand evolved in the absence of mammalian predators and their introduction has been responsible for many extinctions and declines.Introduced species including possums(Trichosurus vulpecula K...The endemic fauna of New Zealand evolved in the absence of mammalian predators and their introduction has been responsible for many extinctions and declines.Introduced species including possums(Trichosurus vulpecula Kerr),ship rats(Rattus rattus L.)and stoats(Mustela erminea L.)are targeted to protect native birds.Control methodologies currently rely largely on labor-intensive trapping or the use of increasingly unpopular poisons,or poisons that are linked with low welfare standards.Hence,the development of safer humane predator toxins and delivery systems is highly desirable.Para-aminopropiophenone(PAPP)is being developed as a toxin for feral cats(Felis catus L.)and stoats.Carnivores appear to be much more susceptible to PAPP than birds,so it potentially has high target specificity,at least in New Zealand.Pen trials with 20 feral cats and 15 stoats have been undertaken using meat baits containing a proprietary formulation of PAPP.A PAPP dose of 20-34 mg kg^(-1)was lethal for feral cats and 37-95 mg kg^(-1)was lethal for stoats.Our assessments suggest that PAPP,for the control of feral cats and stoats,is a humane and effective toxin.PAPP causes methaemoglobinaemia,resulting in central nervous system anoxia,lethargy and death.展开更多
文摘Generalist mammalian predators hunt for prey in different ways than raptors,often relying on ambush attack.Such differences in predator behavior can have profound effects on susceptibility of different species of prey to predation,but can also modify the behavior of prey.We investigated susceptibility of common birds to predation by domestic cats Felis catus,relying on an extensive data set on prey abundance and prey availability as determined by standardized bird counts.Susceptibility to cat predation for different species of birds was not significantly correlated with susceptibility to predation by sparrowhawk Accipiter nisus,but with susceptibility to goshawk Accipiter gentilis predation. Susceptibility to goshawk predation was independently predicted by susceptibility to cat and sparrowhawk predation.We cross-validated our estimate of susceptibilityto cat predation by showing that the frequency of birds with tail loss increased strongly with sus-ceptibility to cat predation.Male birds were disproportionately preyed upon,especially if havingsong posts low in the vegetation,and if having short flight distances when singing.Colonially breeding species were less susceptible to predation than solitary species.Bird species with high levels of innate immune defense against bacterial infections had high susceptibility to cat predation.These findings suggest that predation by cats has been an important selection pressure affecting anti-predation behavior,sexual display and immune function in common birds.
文摘The endemic fauna of New Zealand evolved in the absence of mammalian predators and their introduction has been responsible for many extinctions and declines.Introduced species including possums(Trichosurus vulpecula Kerr),ship rats(Rattus rattus L.)and stoats(Mustela erminea L.)are targeted to protect native birds.Control methodologies currently rely largely on labor-intensive trapping or the use of increasingly unpopular poisons,or poisons that are linked with low welfare standards.Hence,the development of safer humane predator toxins and delivery systems is highly desirable.Para-aminopropiophenone(PAPP)is being developed as a toxin for feral cats(Felis catus L.)and stoats.Carnivores appear to be much more susceptible to PAPP than birds,so it potentially has high target specificity,at least in New Zealand.Pen trials with 20 feral cats and 15 stoats have been undertaken using meat baits containing a proprietary formulation of PAPP.A PAPP dose of 20-34 mg kg^(-1)was lethal for feral cats and 37-95 mg kg^(-1)was lethal for stoats.Our assessments suggest that PAPP,for the control of feral cats and stoats,is a humane and effective toxin.PAPP causes methaemoglobinaemia,resulting in central nervous system anoxia,lethargy and death.
