Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainf...Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainfall) and seasonal variations in daylength on daytime activity budgets. This study showed that the percentage of daytime spent in feeding by feral goats on Rum Island decreased with average monthly temperature, while the percentage of daytime spent in lying increased and rainfall had no significant effects on the percentage daytime spent in feeding or lying. The daylength varied greatly from January to December with the longest daylength being in June and July, and the shortest one in December and January. The amount of daytime spent feeding decreased from summer to winter, although the percentage of daytime spent feeding increased greatly from summer to winter. The seasonal variations in daylength seem to be an important factor in constraining feral goats' activity, especially in the cold and wet winters when forage biomass and quality are both at their lowest level. We discuss the influence of such constraining effects on the forage intake of these goats and their winter survival rate, as well as its implication for population regulation of these goats.展开更多
Objective:To detect and characterize Chlamydophila psittaci(C.psittaci) in asymptomatic feral pigeons in central Thailand.Methods:A total 814 swabs from the trachea and cloacae of 407non-clinical feral pigeons in cent...Objective:To detect and characterize Chlamydophila psittaci(C.psittaci) in asymptomatic feral pigeons in central Thailand.Methods:A total 814 swabs from the trachea and cloacae of 407non-clinical feral pigeons in central Thailand were collected and tested for the presence of C.psittaci.Results:A 10.8%of feral pigeons in the sample group were positive as determined by nested PCR primer specific to C.psittaci.The outer membrane protein A(orupA) gene of positive samples exhibited amino acid identity of C.psittaci ranging from 71 to 100%and were grouped in genotype B.Exceptionally,BF1676-56 isolate was closely related to Chlamydia avium with99%identification of the I6 S ribosomal(r) RNA gene.Conclusions:This is the first report on C.psittaci isolated from asymptomatic feral pigeons in Thailand,which provides knowledge for the disease status in pigeon populations in Thailand.展开更多
Background:Ecological functions and processes in urban ecosystems are governed by various human activities.City-adapted and city-exploiting animal species are expected to present certain specific behavioral and physio...Background:Ecological functions and processes in urban ecosystems are governed by various human activities.City-adapted and city-exploiting animal species are expected to present certain specific behavioral and physiological traits in comparison to city-avoiders or conspecific individual frequenting less urbanized or rural environments.A trait of high importance,the plumage color polymorphism has been selected as the main study model and was correlated with different morphological and physiological parameters to highlight its importance in determining the possible health status of urban Feral Pigeons(Columba livia)in North African urban habitats.Methods:Different body morphometrics,hematological and hemoparasitic parameters were quantified on freeliving Feral Pigeons in urban environments of northern Algeria.Moreover,plumage melanin-based coloration(MBC)was measured and the data collected at the individual scale was correlated with the previous parameters using linear and non-linear modeling approaches.Results:Plumage MBC scores of the sampled Feral Pigeons ranged between 0.3%and 74.8%.Among the 12 morphological traits measured,body weight,tail length and total length were deemed to be positively correlated with MBC.Darker morphs appeared to have more hemoparasites compared to lighter pigeons.Quite the same observation goes with the immunity but with non-linear trends.The number of monocytes and granulocytes increased with the increase in MBC levels in lighter morphs,while pigeons with high MBC scores exhibited negative relationships between MBC levels and the number of white blood cells.Conclusions:Despite the existence of a number of studies demonstrating phenotypic directional selection,further studies are undoubtedly necessary to understand in detail the underlying mechanisms in species life-history strategies between differently colored individuals.Findings of this correlative study open exciting perspectives revealing that MBC can be considered a good indicator of and health status and adaptation strategies to changes in urban environments.展开更多
Numerous recent studies present evidence that Australian dingoes Canis lupus dingo can benefit native biodiversity by suppressing mesopredators and large herbivores. Allen and colleagues have challenged the reliabilit...Numerous recent studies present evidence that Australian dingoes Canis lupus dingo can benefit native biodiversity by suppressing mesopredators and large herbivores. Allen and colleagues have challenged the reliability of this evidence. Al- though they make some valid criticisms, I question some of their assertions. While the existing evidence is inconclusive, I argue that to dismiss it completely would be just as dangerous as to embrace it uncritically. I aim to establish a middle ground .展开更多
Background:Non-native wild pigs(Sus scrofa)threaten sensitive flora and fauna,cost billions of dollars in economic damage,and pose a significant human–wildlife conflict risk.Despite growing interest in wild pig resea...Background:Non-native wild pigs(Sus scrofa)threaten sensitive flora and fauna,cost billions of dollars in economic damage,and pose a significant human–wildlife conflict risk.Despite growing interest in wild pig research,basic life history information is often lacking throughout their introduced range and particularly in tropical environments.Similar to other large terrestrial mammals,pigs possess the ability to shift their range based on local climatic conditions or resource availability,further complicating management decisions.The objectives of this study were to(i)model the distribution and abundance of wild pigs across two seasons within a single calendar year;(ii)determine the most important environmental variables driving changes in pig distribution and abundance;and(iii)highlight key differences between seasonal models and their potential management implications.These study objectives were achieved using zero-inflated models constructed from abundance data obtained from extensive field surveys and remotely sensed environmental variables.Results:Our models demonstrate a considerable change in distribution and abundance of wild pigs throughout a single calendar year.Rainfall and vegetation height were among the most influential variables for pig distribution during the spring,and distance to adjacent forest and vegetation density were among the most significant for the fall.Further,our seasonal models show that areas of high conservation value may be more vulnerable to threats from wild pigs at certain times throughout the year,which was not captured by more traditional modeling approaches using aggregated data.Conclusions:Our results suggest that(i)wild pigs can considerably shift their range throughout the calendar year,even in tropical environments;(ii)pigs prefer dense forested areas in the presence of either hunting pressure or an abundance of frugivorous plants,but may shift to adjacent areas in the absence of either of these conditions;and(iii)seasonal models provide valuable biological information that would otherwise be missed by common modeling approaches that use aggregated data over many years.These findings highlight the importance of considering biologically relevant time scales that provide key information to better inform management strategies,particularly for species whose ranges include both temperate and tropical environments and thrive in both large continental and small island ecosystems.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Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainfall) and seasonal variations in daylength on daytime activity budgets. This study showed that the percentage of daytime spent in feeding by feral goats on Rum Island decreased with average monthly temperature, while the percentage of daytime spent in lying increased and rainfall had no significant effects on the percentage daytime spent in feeding or lying. The daylength varied greatly from January to December with the longest daylength being in June and July, and the shortest one in December and January. The amount of daytime spent feeding decreased from summer to winter, although the percentage of daytime spent feeding increased greatly from summer to winter. The seasonal variations in daylength seem to be an important factor in constraining feral goats' activity, especially in the cold and wet winters when forage biomass and quality are both at their lowest level. We discuss the influence of such constraining effects on the forage intake of these goats and their winter survival rate, as well as its implication for population regulation of these goats.
基金financially supported by the Monitoring and Surveillance Center for Zoonotic Diseases in Wildlife and Exotic Animals.Faculty of Veterinary Science.Mahidol University
文摘Objective:To detect and characterize Chlamydophila psittaci(C.psittaci) in asymptomatic feral pigeons in central Thailand.Methods:A total 814 swabs from the trachea and cloacae of 407non-clinical feral pigeons in central Thailand were collected and tested for the presence of C.psittaci.Results:A 10.8%of feral pigeons in the sample group were positive as determined by nested PCR primer specific to C.psittaci.The outer membrane protein A(orupA) gene of positive samples exhibited amino acid identity of C.psittaci ranging from 71 to 100%and were grouped in genotype B.Exceptionally,BF1676-56 isolate was closely related to Chlamydia avium with99%identification of the I6 S ribosomal(r) RNA gene.Conclusions:This is the first report on C.psittaci isolated from asymptomatic feral pigeons in Thailand,which provides knowledge for the disease status in pigeon populations in Thailand.
基金supported by the DGRSDT and MESRS(Ministry of Higher Education and Scientific Research of Algeria)。
文摘Background:Ecological functions and processes in urban ecosystems are governed by various human activities.City-adapted and city-exploiting animal species are expected to present certain specific behavioral and physiological traits in comparison to city-avoiders or conspecific individual frequenting less urbanized or rural environments.A trait of high importance,the plumage color polymorphism has been selected as the main study model and was correlated with different morphological and physiological parameters to highlight its importance in determining the possible health status of urban Feral Pigeons(Columba livia)in North African urban habitats.Methods:Different body morphometrics,hematological and hemoparasitic parameters were quantified on freeliving Feral Pigeons in urban environments of northern Algeria.Moreover,plumage melanin-based coloration(MBC)was measured and the data collected at the individual scale was correlated with the previous parameters using linear and non-linear modeling approaches.Results:Plumage MBC scores of the sampled Feral Pigeons ranged between 0.3%and 74.8%.Among the 12 morphological traits measured,body weight,tail length and total length were deemed to be positively correlated with MBC.Darker morphs appeared to have more hemoparasites compared to lighter pigeons.Quite the same observation goes with the immunity but with non-linear trends.The number of monocytes and granulocytes increased with the increase in MBC levels in lighter morphs,while pigeons with high MBC scores exhibited negative relationships between MBC levels and the number of white blood cells.Conclusions:Despite the existence of a number of studies demonstrating phenotypic directional selection,further studies are undoubtedly necessary to understand in detail the underlying mechanisms in species life-history strategies between differently colored individuals.Findings of this correlative study open exciting perspectives revealing that MBC can be considered a good indicator of and health status and adaptation strategies to changes in urban environments.
文摘Numerous recent studies present evidence that Australian dingoes Canis lupus dingo can benefit native biodiversity by suppressing mesopredators and large herbivores. Allen and colleagues have challenged the reliability of this evidence. Al- though they make some valid criticisms, I question some of their assertions. While the existing evidence is inconclusive, I argue that to dismiss it completely would be just as dangerous as to embrace it uncritically. I aim to establish a middle ground .
基金supported with a grant from the Hawaiʻi Department of Land and Natural Resource’s Division of Forestry and Wildlife(Grant/Award Number:C01290)。
文摘Background:Non-native wild pigs(Sus scrofa)threaten sensitive flora and fauna,cost billions of dollars in economic damage,and pose a significant human–wildlife conflict risk.Despite growing interest in wild pig research,basic life history information is often lacking throughout their introduced range and particularly in tropical environments.Similar to other large terrestrial mammals,pigs possess the ability to shift their range based on local climatic conditions or resource availability,further complicating management decisions.The objectives of this study were to(i)model the distribution and abundance of wild pigs across two seasons within a single calendar year;(ii)determine the most important environmental variables driving changes in pig distribution and abundance;and(iii)highlight key differences between seasonal models and their potential management implications.These study objectives were achieved using zero-inflated models constructed from abundance data obtained from extensive field surveys and remotely sensed environmental variables.Results:Our models demonstrate a considerable change in distribution and abundance of wild pigs throughout a single calendar year.Rainfall and vegetation height were among the most influential variables for pig distribution during the spring,and distance to adjacent forest and vegetation density were among the most significant for the fall.Further,our seasonal models show that areas of high conservation value may be more vulnerable to threats from wild pigs at certain times throughout the year,which was not captured by more traditional modeling approaches using aggregated data.Conclusions:Our results suggest that(i)wild pigs can considerably shift their range throughout the calendar year,even in tropical environments;(ii)pigs prefer dense forested areas in the presence of either hunting pressure or an abundance of frugivorous plants,but may shift to adjacent areas in the absence of either of these conditions;and(iii)seasonal models provide valuable biological information that would otherwise be missed by common modeling approaches that use aggregated data over many years.These findings highlight the importance of considering biologically relevant time scales that provide key information to better inform management strategies,particularly for species whose ranges include both temperate and tropical environments and thrive in both large continental and small island ecosystems.
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.