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Giant pandas ( Ailuropoda melanoleuca ) are an iconic conservation species, but despite significant research effort, do we understand what they really need? Estimating and mapping suitable habitat play a critical role in conservation planning and policy. But if assumptions about ecological needs are wrong, maps with misidentified suitable habitat will misguide conservation action. Here, we use an information-theoretic approach to analyse the largest, landscape-level dataset on panda habitat use to date, and challenge the prevailing wisdom about panda habitat needs. We show that pandas are associated with old-growth forest more than with any ecological variable other than bamboo. Other factors traditionally used in panda habitat models, such as topographic slope, are less important. We suggest that our findings are disparate from previous research in part because our research was conducted over a larger ecological scale than previous research conducted over more circumscribed areas within individual reserves. Thus, extrapolating from habitat studies on small scales to conservation planning on large scales may entail some risk. As the Chinese government is considering the renewal of its logging ban, it should take heed of the panda's dependency on old growth.

The red panda Ailurus fulgens Cuvier, 1825 is endemic to the Himalayan-Hengduan Mountains. Many of its ecological traits are still poorly understood although important from a scientific standpoint as a highly specialized bamboo feeder. To understand its food habits and space-use, we carried out a field study from April 2002 to May 2003 in Fengtongzhai Nature Reserve, China. The results showed that red pandas almost exclusively fed on Bashania faberi, but not on Yushania brevipaniculata in the study area. Besides differences in nutritional quality, accessibility to food items is perhaps another factor affecting their utilization of bamboo species. B. faberi leaves are the highest in crude protein, being the primary year-round food source; new shoots and fruits of Sorbus, and Rubus are nutritious and digestible, seasonally occurred in their diet. Red pandas seemed to select most nutritious food items to feed on. The home range of red pandas averaged 2.2 km2 across individuals (2.6 km2 for the males and 1.7 km2 for the females), and overlapped extensively (ranging 18.9–78.1%). No significant difference was found in monthly percentage of total home range used among seasons and sexes. The daily movement distance was 455 m (447 m for the females and 463 m for the males), significantly affected by sexes and months. Our findings indicated that food resource significantly influenced behaviour of red pandas in foraging and space use, and their behavioural responses are adaptive being helpful to energy intake and maintenance.

We studied the denning ecology of giant pandas (Ailuropoda melanoleuca) in the Foping Nature Reserve, China. We identified 17 used and 21 unused cavities of appropriate size to accommodate denning and measured several variables potentially affecting the suitability of these cavities for panda denning. Principal component analysis, combined with traditional univariate tests, indicated that maternal females preferred deeper cavities with a high interior-to-entrance ratio for height and width, suggesting a preference for narrow entrances and roomy chambers. Microhabitat features, including slope and distance to water, were also useful in predicting den use by maternal females. We believe that the availability of suitable dens may limit population size, especially in areas where tree dens have been eliminated by logging of old growth forests. Conservation managers in giant panda reserves can use our data to determine the number of suitable panda dens that are in an area, estimate whether there are enough for the adult female population to use as birthing dens, and—if needed—construct suitable artificial dens to increase the rate of reproduction.

The giant panda (Ailuropoda melanoleuca) is currently threatened by habitat loss, fragmentation, and human persecution. Its dietary specialization, habitat isolation, and reproductive constraints have led to a perception that this is a species at an "evolutionary dead end," destined for deterministic extinction in the modern world. Here we examine this perception by a comprehensive investigation of its genetic diversity, population structure, and demographic history across its geographic range. We present analysis of 655 base pairs of mitochondrial (mt) control region (CR) DNA and 10 microsatellite loci for samples from its 5 extant mountain populations (Qinling, Minshan, Qionglai, Liangshan, and Lesser Xiangling). Surprisingly, extant populations display average to high levels of CR and microsatellite diversity compared with other bear species. Genetic differentiation among populations was significant in most cases but was markedly higher between Qinling and the other mountain ranges, suggesting, minimally, that the Qinling population should comprise a separate management unit for conservation purposes. Recent demographic inference using microsatellite markers demonstrated a clear genetic signature for population decline starting several thousands years ago or even further back in the past, and being accelerated and enhanced by the expansion of human populations. Importantly, these data suggest that the panda is not a species at an evolutionary "dead end," but in common with other large carnivores, has suffered demographically at the hands of human pressure. Conservation strategies should therefore focus on the restoration and protection of wild habitat and the maintenance of the currently substantial regional genetic diversity, through active management of disconnected populations.

Abstract Human activities have been a main cause of floral and faunal species extinction and loss of local and global biodiversity. Habitat and population can become fragmented and isolated under anthropogenic disturbances. In this study, we focus on the effect of human activities on the habitat and population of the giant panda (Ailuropoda melanoleuca) in the north slopes of Daxiangling Mountains, Sichuan province, China. Based on eight months of field investigation in 2004, we found that the distribution of the giant panda population has been limited to remnants of habitat due to human activities such as road construction, mining and hydropower stations. There is 100.60 km2 area suitable for the giant panda (including moderately suitable, suitable and most suitable), which only accounts for 21.33% of the bamboo area. Based on a dispersal model COST, there were 79.94 km2 areas (17.12%) (including moderately suitable, suitable and most suitable) for giant panda utilization in reality. Only 16.35 km2 areas (3.5%) of total bamboo area were most suitable. The areas that suitable for panda had decreased 20.66 km2 from 2000 in total due to people activities. The results of this study can be used to provide basic information to build nature reserve for protecting giant panda in Daxiangling Mountains.

The reproduction of female red pandas under three different husbandry conditions (monogamy, polygamy, and polyandry) was studied at the Chengdu Research Base for Giant Panda Breeding, and Chengdu Zoological Park, China. We monitored the fecal steroid profiles of seven females by radioimmunoassay in order to understand how the different mating groupings affect the animals' reproductive success. Of the seven females studied, all gave birth except the one that was kept in the polyandrous group. Although fecal estradiol metabolites exhibited several peaks during estrus, only one coincided with mating behavior. Fecal progesterone metabolites did not display a sustained rise in the absence of mating behavior, even though estradiol displayed a peak of secretion. This suggests that the red panda may be an induced ovulator. During gestation, fecal progesterone metabolites were maintained at a comparatively high level, and were much higher than those of nonpregnant females. The female in the polyandrous group showed an abnormal estradiol metabolite profile, with a level that was four to five times higher than those of the females in the polygynous groupings. It was observed that this female always escaped and hid in the trees to avoid courtships with males, and did not give birth. This phenomenon suggests that polyandrous groupings may be unsuitable for successful reproduction in captivity. Zoo Biol 24:169–176, 2005. © 2005 Wiley-Liss, Inc.

The giant panda (Ailuropoda melanoleuca (David, 1869)), red panda (Ailurus fulgens F.G. Cuvier, 1825), and tufted deer (Elaphodus cephalophus Milne-Edwards, 1872) are endemic to the Himalayan Hengduan Mountains; the red panda extends into India, Burma, Bhutan, and Nepal, and the tufted deer extends marginally into Burma, while the giant panda is endemic to China. In Sichuan Province, uniquely, all three species occur sympatrically. We investigated microhabitat characteristics at 150 fecal-group sites from November 2002 to March 2003 to improve understanding of microhabitat separation among the three species at the Fengtongzhai Nature Reserve, Baoxing County, Sichuan Province, People's Republic of China. Density and height of bamboo were greater in the giant and red pandas' micro habitats than in those of the tufted deer. The red panda preferred microhabitats with greater tree-stump density, smaller trees, and shorter fallen log dispersion distance than the other two species. Tufted deer often occurred at sites with greater shrub density and herb cover and more open land with poorer concealment conditions than sites where the two panda species occurred. Both pandas' microhabitats were mostly concentrated on the upper hillside, unlike those of the tufted deer. The giant panda preferred microhabitats with a gentler slope and lower density of fallen logs. Selection of specific microhabitats by each species is an ecological adaptation dependent on behavior linked to its diet, body size, energy metabolism, and other factors. Microhabitat separation among these species reflects the integrated effects of their differences in diet, body size, and energy metabolism, which could facilitate their successful coexistence.

To investigate the genetic structure within the takin (Budorcas taxicolor), a little-studied and threatened species, portions of the mitochondrial DNA control region and cytochrome b gene were sequenced from 40 takins from three subspecies and 10 separate geographical locations in China. Overall variation among individuals was low. Both neighbor-joining and parsimony analyses did separate animals into three distinct clades reflecting the subspecific definitions, with only one locality grouping with a clade distinct from its purported subspecies. Animals within each clade were genetically similar to each other, which we hypothesize is due to the mobility of the animals leading to significant gene flow within each region until recent habitat alteration limited movements. We also suggest that genetic bottlenecks survived by the species since the end of the Pleistocene may have contributed to overall low levels of variability within the species.

We describe an improved mathematical model for the relationship between the population of giant pandas (Ailuropoda melanoleuca) and bamboo (Bashania spanostachya) developed by Smith (1979) and Yuan et al. (1989), by adding a correction term which takes into account the effect of a sudden collapse of bamboo as a food source. The values for the co-efficients were based on field data collected in 1994 and 1995 in Yele Nature Reserve (Mianning county, Sichuan Province). The model reflects the dynamic relationship between giant pandas and bamboo in Xiangling Mountains. It is more realistic than earlier models. The density dependent co-efficient for bamboo in the model, Parameter a, decides whether the positive equilibrium point B is a stable or an unstable focus as a changes. The branching value a0 exists in a very narrow interval. The fundamental structure of the phase graph of the model changes significantly and one stable limit cycle is obtained.

Small populations are subject to large fluctuations arising from random processes at a variety of levels (genetic drift, demographic variation and environmental catastrophes), and such variation can place a population at high risk of extinction. The giant panda (Ailuropoda melanoleuca) has been studied extensively over a long period of time. Population trends can be estimated by Population Viability Analysis (PVA) in computer simulation models. Four possible scenarios were used in a Vortex computer model (Miller & Lacy 1999) to project the likely outcome of population change of the current panda population in the Yele Nature Reserve of western China. The results show that the number of pandas will slowly increase with no inbreeding and no environmental catastrophes (floods, fires, disease, etc.). However, when the model includes an inbreeding rate or a 1.67% probability of an environmental catastrophe, the population becomes extinct in 90 years and 60 years, respectively. The low viability projections of this isolated panda population, require strategies for restoring habitat quality of the Yele Nature Reserve.

Habitat use and separation between 2 sympatric species, the giant panda (Ailuropoda melanoleuca) and the red panda (Ailurus fulgens), were studied in Yele Natural Reserve, Mianning County of Sichuan Province, China, to elucidate the coexistence of these specialized carnivores. Nineteen variables describing proximate habitat structure were measured at each fecal-group site. We tested if habitat structure differed between pandas and examined habitat separation between the species. Habitats used by each species differed significantly. The 2 pandas exhibited different patterns in microhabitat use, although their habitats overlapped in the study area. The giant panda occurred at sites on gentle slopes with lower density of fallen logs, shrubs, and bamboo culms. Sites also were close to trees and far from fallen logs, shrubs, and tree stumps. The red panda occurred at sites on steeper slopes with higher density of fallen logs, shrubs, and bamboo culms. Sites also were close to fallen logs, shrubs, and tree stumps. We conclude that microhabitat separation contributes to coexistence of giant and red pandas in areas of sympatry.

The red panda is classed as a category II species under the Wild Animal Protection Law in China. Both subspecies, Ailurus fulgens fulgens and A. f. styani can be found there. However, the styani subspecies is more typical of the region. According to the survey conducted from 1994 to 1996, red pandas now can only be found in Sichuan, Yunnan and Tibet. They have become extinct throughout the rest of their original range, e.g. in Guizhou, Gansu, Shaanxi and Qinghai provinces. The investigation shows that there are 76 245.5 km 2 of forest available within the current range, including 35 088.3 km 2 in Sichuan, 21 658.1 km 2 in Yunnan and 19 499.1 km 2 in Tibet, respectively. However, their habitat is only 37 436.5 km 2 (17 228.3 km 2 in Sichuan province, 10 634.1 km 2 in Yunnan province and 9574.1 km 2 in Tibet) because of a high preference for a particular habitat. It is estimated that their numbers may have decreased by as much as 40% over the last 50 years due to massive habitat loss, increasing human activity and poaching. Total population numbers estimated are about 6000–7000 in China, including 3000–3400 in Sichuan, 1600–2000 in Yunnan, 1400–1600 in Tibet. However, the Chinese government pays much more attention to wildlife protection today. It has launched a series of laws and regulations and established a lot of national reserves or parks as refuges for wildlife. To date 31 reserves have been established within the red panda's range: 18 in Sichuan, 7 in Yunnan and 6 in Tibet. These reserves together protect 15,864.9 km 2 of red panda habitat. This represents about 42.4% of the red panda's habitat in China.

Nutrient use by the red panda Ailurus fulgens was measured in animals fed only on their natural bamboo Bashania spanostachya diet. The project was carried out at the field observation station of Yele Natural Reserve in Sichuan, China. Two-week long trials were conducted at monthly intervals from May to November 1995. Results showed that dry matter digestibility differed significantly among seasons and between diets. Digestibilities of dry matter and key nutrients were high in summer–autumn, intermediate in spring and low in winter. Shoots were more easily digested than leaves and exhibited the highest digestibility. These variations were positively correlated with nutrient contents in bamboo. The results also indicated that the red panda poorly processed its bamboo food. This was demonstrated by the lower digestion coefficients of dry matter and nutrients, especially that of cell wall constituents. This implied that microbial digestion only played a minor role in its digestive strategy, similar to the giant panda Ailuropoda melanoleuca, another herbivorous carnivore. In addition, the transit of bamboo through the red panda gut was very rapid (2–4 h). In order to survive on this poor-quality diet, it seems that the red panda has to select high-quality items of bamboo such as tender leaves and shoots. These are ingested in large quantities (over 1.5 kg of fresh leaves and 4 kg of fresh shoots daily) that pass through the digestive tract fairly rapidly so as to maximize nutrient intake.

We describe the isolation and characterization of 14 microsatellite loci in the striped field mouse from genomic DNA-enriched libraries in this paper. The 14 new loci were tested in 24 individuals from four populations in Southwest China. These loci were highly polymorphic with numbers of alleles per locus ranging from 6 to 14 and expected heterozygosities from 0.789 to 0.925. All loci followed Hardy–Weinberg expectations except SFM4, SFM11 and SFM13 loci. No significant linkage association was found among all loci. The 14 novel polymorphic microsatellite loci will be useful in studying phylogeography and population genetics of the striped field mouse.

In wireless sensor networks (WSNs), these sensor nodes cooperate with each other to form a network without using any infrastructure. WSNs has a wide application. But the security of WSNs is still an issue. Traditionally cryptographic mechanisms such as authentication and encryption only address part of the problem of security in WSNs. Recently, the use of reputation and trust systems has become an important mechanism in WSNs. In this paper, we develop a distributed agent-based trust management scheme. The agent node use watchdog mechanism to observe the behavior of the sensor nodes and computes the trust rating for them. We consider packet-dropping and hello flood attack in our simulation, the simulation results and analysis show that our scheme can fast detect the malicious nodes and scale well for wireless sensor networks.

Foraging patches can be described as a nested hierarchy of aggregated resources, implying that study of foraging by wild animals should be directed across different spatial scales. However, almost all previous research on habitat selection by the giant panda has concentrated upon one scale. In this research, we carried out a field study to understand foraging patch selection by giant pandas in winter at both microhabitat and feeding site scales and, for the first time, attempted to understand how long it would stay at the feeding sites before moving on.The field survey was conducted from November 2002 to March 2003 at Fengtongzhai Nature Reserve (102 degrees 48'-103 degrees 00' E, 30 degrees 19'-30 degrees 47' N), Baoxing County of Sichuan Province, China, to collect data in both microhabitat and control plots. The microhabitat plots were located by fresh feces or foraging traces left by giant pandas, and the control plots were established to reflect the environment. Within each microhabitat plot, one 1x1 m2 plot was centralized at the center of each feeding site, in which numbers of old bamboos and old shoots, including eaten and uneaten, were counted, respectively.The results showed that winter microhabitats selected by this species were characteristic of gentle slopes and high old-shoot proportions and that the latter was even higher at feeding sites. Two selection processes, namely, from the environment to microhabitats and from the latter to feeding sites, were found during this species' foraging patch utilization. Giant pandas preferred to eat old shoots to old bamboo at feeding sites in winter and did not leave unless old-shoot density fell to lower than the average in the environment.Both microhabitats and feeding sites selected by giant pandas were characteristic of high old-shoot density, indicating that the preferred food item had a significant influence upon its foraging patch selection. The preference for gentle slopes by giant pandas was presumed to save energy in movement or reflect the need to sit and free its fore-limbs to grasp bamboo culms when feeding but also seemed to be correlated with an easier access to old shoots. The utilization of old shoots at feeding sites was assumed to help maximize energy or nutrient intake during their foraging.The difference between microhabitat plots and control plots and between microhabitats and feeding sites uncovered a continuous selection process from the environment via microhabitats to feeding sites. The utilization of old shoots at feeding sites was parallel to the marginal value theorem. The selection and abandonment of foraging patches by giant pandas was an optimal behavioral strategy adapted to their peculiar food with high cellulose and low protein.Our results uncovered the importance of multiple scales in habitat selection research. To further understand the process of habitat selection, future research should pay more attention to resolve the question of how to locate foraging patches under dense bamboo forests by the giant panda, which was traditionally considered to have poor eyesight, although our research has answered what type of habitats the giant panda prefers and when to leave.

Phylogenetic relationships among 15 species of wood mice (genus Apodemus) were reconstructed to explore some long-standing taxonomic problems. The results provided support for the monophyly of the genus Apodemus, but could not reject the hypothesis of paraphyly for this genus. Our data divided the 15 species into four major groups: (1) the Sylvaemus group (A. sylvaticus, A. flavicollis, A. alpicola, and A. uralensis), (2) the Apodemus group (A. peninsulae, A. chevreri, A. agrarius, A. speciosus, A. draco, A. ilex, A. semotus, A. latronum, and A. mystacinus), (3) A. argenteus, and (4) A. gurkha. Our results also suggested that orestes should be a valid subspecies of A. draco rather than an independent species; in contrast, A. ilex from Yunnan may be regarded as a separate species rather than a synonym of orestes or draco. The species level status of A. latronum, tscherga as synonyms of A. uralensis, and A. chevrieri as a valid species and the closest sibling species of A. agrarius were further corroborated by our data. Applying a molecular clock with the divergences of Mus and Rattus set at 12 million years ago (Mya) as a calibration point, it was estimated that five old lineages (A. mystacinus and four major groups above) diverged in the late Miocene (7.82-12.74 Mya). Then the Apodemus group (excluding A. mystacinus) split into two subgroups: agrarius and draco, at about 7.17-9.95 Mya. Four species of the Sylvaemus group were estimated to diverge at about 2.92-5.21 Mya. The Hengduan Mountains Region was hypothesized to have played important roles in Apodemus evolutionary histories since the Pleistocene.