Background: Breeding dispersal is an important ecological process that affects species' population dynamics and colonization of new suitable areas. Knowledge of the causes and consequences of breeding dispersal is...Background: Breeding dispersal is an important ecological process that affects species' population dynamics and colonization of new suitable areas. Knowledge of the causes and consequences of breeding dispersal is fundamental to our understanding of avian ecology and evolution. Although breeding success for a wild and reintroduced population of the Crested Ibis(Nipponia nippon) has been reported, the relationships between individuals' breeding dispersal and their breeding success, age and sex remain unclear.Methods: Ibises' breeding dispersal distance, which is the distance moved by adults between sites of reproduction, was estimated based on the observations of consecutive breeding sites of marked ibis individuals. From observational and capture-recapture data(n as = 102) over 9 years, individuals' breeding dispersal probability in relation to age, sex, and reproductive success wanalyzed via a generalized linear mixed effect modeling approach.Results: Our results show that 55% males and 51% females keep their previous territories following nesting success. Failed breeding attempts increased dispersal probabilities. Both females and males failed in breeding were more likely to disperse with greater distances than successful birds(females: 825 ± 216 m vs 196 ± 101 m, males: 372 Crested Ibis exhibited a female-biased dispersal pattern that the mean dispersal distance± 164 m vs 210 ± 127 m). of females(435 ± 234 m) was much larger than that of males(294 ± 172 m).Conclusion: Our results are fundamental to predict the patterns of breeding dispersal related to reproductive success under different release sites. From the conservation point of view, landscape connectivity between the reintroduced populations should be taken into account in accordance with the distance of breeding dispersal.展开更多
Background:One of the most challenging tasks in wildlife conservation and management is clarifying which and how external and intrinsic factors influence wildlife demography and long-term viability.The wild population...Background:One of the most challenging tasks in wildlife conservation and management is clarifying which and how external and intrinsic factors influence wildlife demography and long-term viability.The wild population of the Crested Ibis(Nipponia nippon)has recovered to approximately 4400,and several reintroduction programs have been carried out in China,Japan and Korea.Population viability analysis on this endangered species has been limited to the wild population,showing that the long-term population growth is restricted by the carrying capacity and inbreeding.However,gaps in knowledge of the viability of the reintroduced population and its drivers in the release environment impede the identification of the most effective population-level priorities for aiding in species recovery.Methods:The field monitoring data were collected from a reintroduced Crested Ibis population in Ningshan,China from 2007 to 2018.An individual-based VORTEX model(Version 10.3.5.0)was used to predict the future viability of the reintroduced population by incorporating adaptive patterns of ibis movement in relation to catastrophe frequency,mortality and sex ratio.Results:The reintroduced population in Ningshan County is unlikely to go extinct in the next 50 years.The popula-tion size was estimated to be 367,and the population genetic diversity was estimated to be 0.97.Sensitivity analysis showed that population size and extinction probability were dependent on the carrying capacity and sex ratio.The carrying capacity is the main factor accounting for the population size and genetic diversity,while the sex ratio is the primary factor responsible for the population growth trend.Conclusions:A viable population of the Crested Ibis can be established according to population viability analysis.Based on our results,conservation management should prioritize a balanced sex ratio,high-quality habitat and low mortality.展开更多
Reintroduction has become a common conservation management tool to restore endangered species in their historical range.However,many attempts have failed to establish self-sustaining populations in the wild.The succes...Reintroduction has become a common conservation management tool to restore endangered species in their historical range.However,many attempts have failed to establish self-sustaining populations in the wild.The success of reintroductions could be improved by varying release strategies.Therefore,it is vital to determine the factors influencing reintroduction outcomes.To better understand the post-release settlement and to optimize the release strategy of the Crested Ibis(Nipponia nippon),we quantified the effects of age,sex,acclimation duration,and the timing of release events on post-release survival and dispersal distance for the released Crested Ibis in Tongchuan City,Shaanxi Province,using a generalized linear mixed effect modeling approach.Our results indicate that 40–56.3%of the released individuals survived the first year following release.Mortality was attributable to flight collisions,starvation,disease,and unknown reasons.The post-release survival probability of ibises showed a negative association with age(estimate=-0.186;95%CI:-0.350 to-0.022;P=0.026),and post-release dispersal distance was affected by the timing of release event(estimate=0.718;95%CI:0.025 to1.253;P=0.042).However,sex and acclimation period duration did not cause detectable differences in postrelease survival probability and dispersal distance.Based on our results,optimal release strategies for establishing a reintroduced population of the Crested Ibis include:(1)release of sub-adults biased and sex ratio balanced initial groups;(2)release during the non-breeding season;and(3)food supplementation immediately after release.展开更多
Understanding how species’ecological niches adapt to environmental changes through time is critical for predicting the effect of future global change on endangered species.Yet few studies have incorporated knowledge ...Understanding how species’ecological niches adapt to environmental changes through time is critical for predicting the effect of future global change on endangered species.Yet few studies have incorporated knowledge of past niche shifting into the assessment of species’future fate in a changing world.In this study,we integrated the ecological niche dynamics into the species distribution modeling of the Asian crested ibis(Nipponia nippon)in East Asia.Specifically,we compared historical and present ecological niches of crested ibis in four-dimensional environmental space based on species occurrence and environmental data.We then employed a multi-temporal ecological niche model to estimate the potential geographical distribution of crested ibis under future climate and land-use changes.Our results show that crested ibis retained similar though not identical ecological niches over time.Compared to the historical baseline range,the current suitable habitat for crested ibis has been reduced by 39.6%.The effects of human activity outweigh those of climate change regarding the distribution of crested ibis.We conclude that the ecological niche of crested ibis was tended to be conservative,and future potentially suitable habitat may encounter northeastward and northwestward shift,and possibly expand by 18.7%referred to the historical range.Thefindings of our study are of clear importance for the conservation and successful reintroduction of crested ibis in East Asia.展开更多
基金completely supported by the National Nature Science Foundation of China(Nos.31572282 and 31172103)
文摘Background: Breeding dispersal is an important ecological process that affects species' population dynamics and colonization of new suitable areas. Knowledge of the causes and consequences of breeding dispersal is fundamental to our understanding of avian ecology and evolution. Although breeding success for a wild and reintroduced population of the Crested Ibis(Nipponia nippon) has been reported, the relationships between individuals' breeding dispersal and their breeding success, age and sex remain unclear.Methods: Ibises' breeding dispersal distance, which is the distance moved by adults between sites of reproduction, was estimated based on the observations of consecutive breeding sites of marked ibis individuals. From observational and capture-recapture data(n as = 102) over 9 years, individuals' breeding dispersal probability in relation to age, sex, and reproductive success wanalyzed via a generalized linear mixed effect modeling approach.Results: Our results show that 55% males and 51% females keep their previous territories following nesting success. Failed breeding attempts increased dispersal probabilities. Both females and males failed in breeding were more likely to disperse with greater distances than successful birds(females: 825 ± 216 m vs 196 ± 101 m, males: 372 Crested Ibis exhibited a female-biased dispersal pattern that the mean dispersal distance± 164 m vs 210 ± 127 m). of females(435 ± 234 m) was much larger than that of males(294 ± 172 m).Conclusion: Our results are fundamental to predict the patterns of breeding dispersal related to reproductive success under different release sites. From the conservation point of view, landscape connectivity between the reintroduced populations should be taken into account in accordance with the distance of breeding dispersal.
基金The study was supported by Shaanxi Forestry Bureau and National Natural Science Foundation of China(Grant Nos.31872245 and 31572282).
文摘Background:One of the most challenging tasks in wildlife conservation and management is clarifying which and how external and intrinsic factors influence wildlife demography and long-term viability.The wild population of the Crested Ibis(Nipponia nippon)has recovered to approximately 4400,and several reintroduction programs have been carried out in China,Japan and Korea.Population viability analysis on this endangered species has been limited to the wild population,showing that the long-term population growth is restricted by the carrying capacity and inbreeding.However,gaps in knowledge of the viability of the reintroduced population and its drivers in the release environment impede the identification of the most effective population-level priorities for aiding in species recovery.Methods:The field monitoring data were collected from a reintroduced Crested Ibis population in Ningshan,China from 2007 to 2018.An individual-based VORTEX model(Version 10.3.5.0)was used to predict the future viability of the reintroduced population by incorporating adaptive patterns of ibis movement in relation to catastrophe frequency,mortality and sex ratio.Results:The reintroduced population in Ningshan County is unlikely to go extinct in the next 50 years.The popula-tion size was estimated to be 367,and the population genetic diversity was estimated to be 0.97.Sensitivity analysis showed that population size and extinction probability were dependent on the carrying capacity and sex ratio.The carrying capacity is the main factor accounting for the population size and genetic diversity,while the sex ratio is the primary factor responsible for the population growth trend.Conclusions:A viable population of the Crested Ibis can be established according to population viability analysis.Based on our results,conservation management should prioritize a balanced sex ratio,high-quality habitat and low mortality.
基金supported by National Natural Science Foundation of China(No.31572282,31872245)Shaanxi Forestry Bureau。
文摘Reintroduction has become a common conservation management tool to restore endangered species in their historical range.However,many attempts have failed to establish self-sustaining populations in the wild.The success of reintroductions could be improved by varying release strategies.Therefore,it is vital to determine the factors influencing reintroduction outcomes.To better understand the post-release settlement and to optimize the release strategy of the Crested Ibis(Nipponia nippon),we quantified the effects of age,sex,acclimation duration,and the timing of release events on post-release survival and dispersal distance for the released Crested Ibis in Tongchuan City,Shaanxi Province,using a generalized linear mixed effect modeling approach.Our results indicate that 40–56.3%of the released individuals survived the first year following release.Mortality was attributable to flight collisions,starvation,disease,and unknown reasons.The post-release survival probability of ibises showed a negative association with age(estimate=-0.186;95%CI:-0.350 to-0.022;P=0.026),and post-release dispersal distance was affected by the timing of release event(estimate=0.718;95%CI:0.025 to1.253;P=0.042).However,sex and acclimation period duration did not cause detectable differences in postrelease survival probability and dispersal distance.Based on our results,optimal release strategies for establishing a reintroduced population of the Crested Ibis include:(1)release of sub-adults biased and sex ratio balanced initial groups;(2)release during the non-breeding season;and(3)food supplementation immediately after release.
基金supported by the National Natural Science Foundation of China(No.41901060,No.31672310)the National Key Research and Development Program of China(No.2016YFC0503200).
文摘Understanding how species’ecological niches adapt to environmental changes through time is critical for predicting the effect of future global change on endangered species.Yet few studies have incorporated knowledge of past niche shifting into the assessment of species’future fate in a changing world.In this study,we integrated the ecological niche dynamics into the species distribution modeling of the Asian crested ibis(Nipponia nippon)in East Asia.Specifically,we compared historical and present ecological niches of crested ibis in four-dimensional environmental space based on species occurrence and environmental data.We then employed a multi-temporal ecological niche model to estimate the potential geographical distribution of crested ibis under future climate and land-use changes.Our results show that crested ibis retained similar though not identical ecological niches over time.Compared to the historical baseline range,the current suitable habitat for crested ibis has been reduced by 39.6%.The effects of human activity outweigh those of climate change regarding the distribution of crested ibis.We conclude that the ecological niche of crested ibis was tended to be conservative,and future potentially suitable habitat may encounter northeastward and northwestward shift,and possibly expand by 18.7%referred to the historical range.Thefindings of our study are of clear importance for the conservation and successful reintroduction of crested ibis in East Asia.
