The Groundpecker (Pseudopodoces humilis)is an en demic species of a genus endemic to China.Althoug hit had been considered a member of the corvidae for centuries.It has recently been put in Family Paridae by James et ...The Groundpecker (Pseudopodoces humilis)is an en demic species of a genus endemic to China.Althoug hit had been considered a member of the corvidae for centuries.It has recently been put in Family Paridae by James et al. ( 2 0 0 0 ,2 0 0 3 ) .It’s English name should be changed to the Ground tit.展开更多
The Xinjiang Ground Jay (Podoces biddulphi) is a bird species endemic to China. It has a restricted range, living only in the Taklimakan Desert, southern part of Xinjiang. So far, little information has been known of ...The Xinjiang Ground Jay (Podoces biddulphi) is a bird species endemic to China. It has a restricted range, living only in the Taklimakan Desert, southern part of Xinjiang. So far, little information has been known of the status and ecology of the bird in the world. Since 1988, I have been taking field investigations on the distribution, population size and breeding ecology of the Xinjiang Ground Jay in the desert.In this thesis, the desertification in relation to the eastward expansion of the ground jays was discussed.展开更多
Considering a recent proposition on this journal that the endemic Xinjiang Ground Jay (Podoces biddulphi) would be expanding its range to Qinghai and Gansu, a previously overlooked statement has been found in old lite...Considering a recent proposition on this journal that the endemic Xinjiang Ground Jay (Podoces biddulphi) would be expanding its range to Qinghai and Gansu, a previously overlooked statement has been found in old literature suggesting that this species has occurred in Gansu at least since the 19th century. The phreatophytic vegetation this desert bird requires likely constrains its distribution. Therefore, although the desert expansion the current global climate warming is producing may make the Xinjiang Ground Jay expand its range, only well-preserved desert might be colonized. Future research in apparently suitable areas, at present inhabited by the Mongolian Ground Jay (P. hendersoni) instead, might make the ecology of these two mutually exclusive species better understood.展开更多
Scatter hoarding by corvids （crows, jays, magpies, and nutcrackers） provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throu...Scatter hoarding by corvids （crows, jays, magpies, and nutcrackers） provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throughout the landscape, resulting in differential survival of seeds. In the context of habitat restoration, such disproportional storing of seeds in areas suitable for germin- ation and establishment can accelerate expansion and recovery of large-seeded tree populations and their associated ecosystems. Here, we investigate the spatial preferences of island scrub jays Aphelocoma insularis during scatter hoarding of acorns （Quercus spp.） on Santa Cruz Island. We use a large behavioral data set on the birds＇ behavior in combination with seedling surveys and spatial analysis to determine whether 1） island scrub jays disproportionally cache seeds in specific habitat types, and 2） whether the preferred habitat type is suitable for oak regeneration. Our results show that the jays nonrandomly cache acorns across the landscape; they use chaparral and coastal sage scrub disproportionally while avoiding open and grassy areas. The areas used most often for caching were also the areas with the highest oak seedling densities. We discuss the potential role of these findings for the recovery of Santa Cruz Island＇s oak habitat since the 1980s.展开更多
文摘The Groundpecker (Pseudopodoces humilis)is an en demic species of a genus endemic to China.Althoug hit had been considered a member of the corvidae for centuries.It has recently been put in Family Paridae by James et al. ( 2 0 0 0 ,2 0 0 3 ) .It’s English name should be changed to the Ground tit.
基金supported by the Science Supporting Project of National Ministry of Science and Technology(2008BAC39B04)the National Natural Science Foundation of China(30270211,30470262,30970340)
文摘The Xinjiang Ground Jay (Podoces biddulphi) is a bird species endemic to China. It has a restricted range, living only in the Taklimakan Desert, southern part of Xinjiang. So far, little information has been known of the status and ecology of the bird in the world. Since 1988, I have been taking field investigations on the distribution, population size and breeding ecology of the Xinjiang Ground Jay in the desert.In this thesis, the desertification in relation to the eastward expansion of the ground jays was discussed.
文摘Considering a recent proposition on this journal that the endemic Xinjiang Ground Jay (Podoces biddulphi) would be expanding its range to Qinghai and Gansu, a previously overlooked statement has been found in old literature suggesting that this species has occurred in Gansu at least since the 19th century. The phreatophytic vegetation this desert bird requires likely constrains its distribution. Therefore, although the desert expansion the current global climate warming is producing may make the Xinjiang Ground Jay expand its range, only well-preserved desert might be colonized. Future research in apparently suitable areas, at present inhabited by the Mongolian Ground Jay (P. hendersoni) instead, might make the ecology of these two mutually exclusive species better understood.
文摘Scatter hoarding by corvids （crows, jays, magpies, and nutcrackers） provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throughout the landscape, resulting in differential survival of seeds. In the context of habitat restoration, such disproportional storing of seeds in areas suitable for germin- ation and establishment can accelerate expansion and recovery of large-seeded tree populations and their associated ecosystems. Here, we investigate the spatial preferences of island scrub jays Aphelocoma insularis during scatter hoarding of acorns （Quercus spp.） on Santa Cruz Island. We use a large behavioral data set on the birds＇ behavior in combination with seedling surveys and spatial analysis to determine whether 1） island scrub jays disproportionally cache seeds in specific habitat types, and 2） whether the preferred habitat type is suitable for oak regeneration. Our results show that the jays nonrandomly cache acorns across the landscape; they use chaparral and coastal sage scrub disproportionally while avoiding open and grassy areas. The areas used most often for caching were also the areas with the highest oak seedling densities. We discuss the potential role of these findings for the recovery of Santa Cruz Island＇s oak habitat since the 1980s.
