Identifying priority protection areas of key food resources of the giant panda.

Animals that live in seasonal environments adjust their reproduction cycle to optimize seasonal forage quality. Giant pandas ( Ailuropoda melanoleuca) are seasonal altitudinal migrants that feed on bamboo shoots and leaves with different nutritional quality. However, the importance of bamboo shoots to giant pandas, especially small and isolated populations, is not fully appreciated. Here, we explored whether mating time of giant pandas is shaped by bamboo shoot phenology. We also assessed the intensity of ongoing bamboo shoot harvesting by local communities in 42 giant panda reserves based on questionnaire surveys. Varying intensity and protection levels of bamboo shoot harvesting were found. From these data, we developed a priority ranking scheme of protection areas for this key food resource. Our study showed that pandas time their mating behavior to coincide with bamboo shoot phenology due to the high nutritional demands associated with mating and pregnancy. We also found that bamboo shoots were not well protected in many places. Liangshan, Daxiangling, and Xiaoxiangling, containing the most isolated panda populations, were identified as the areas with the most urgent need of protection. Furthermore, equal attention should be paid to the QiongL-B population, as this region holds considerable potential to serve as a corridor between the Minshan and Qionglai populations. To address the challenges posed by bamboo shoot harvesting, we recommend establishing more practical bamboo shoot management policies, increasing public awareness of bamboo shoot protection, and providing alternative sources of income for local communities.

Stable seasonal migration patterns in giant pandas.

A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous environments. Seasonally mediated resource fluctuations may influence animal movements, enabling them to track changing resource distributions, resulting in annual migration patterns. The conservation-dependent giant panda ( Ailuropoda melanoleuca) displays seasonal movement patterns; however, the key factor driving these seasonal migration patterns remains poorly understood. Here, we used GPS tracking collars to monitor the movements of six giant pandas over a 12-year period across different elevations, and performed statistical analysis of seasonal migration directions, routes, habitat revisitation, home range overlap, first arrival events, and stability. Our results revealed a compelling pattern of seasonal migrations that facilitated the ability of the pandas to forage at the appropriate time and place to maximize nutritional intake. Our results indicated that pandas utilize spatial memory to locate reliable food resources, as evidenced by their annual return to the same or similar winter and summer home ranges and the consistently maintained percentage of home range overlap. These novel insights into giant panda foraging and movement ecology not only enhance our understanding of its ability to adapt to nutritionally poor dietary resources but also provide important information for the development of resource utilization-based protection and management strategies.

Impact of sympatric carnivores on den selection of wild giant pandas.

Interspecific killing is a primary reason for the low survival rates of some animal species. The giant panda ( Ailuropoda melanoleuca) is an altricial eutherian mammal and thus, in comparison to other infants, panda cubs are highly vulnerable, which may significantly influence the selection of breeding sites by females. Here, we used infrared camera traps to monitor giant panda dens for 5.5 years in Foping National Nature Reserve (FNNR) to determine how interspecific factors affect den selection by wild female pandas. Results indicated that Asian black bears ( Ursus thibetanus), yellow-throated martens ( Martes flavigula), leopard cats ( Prionailurus bengalensis), and masked palm civets ( Paguma larvata) visited the dens frequently, and the presence of these species negatively influenced den selection by female pandas. Interestingly, the presence of rodents and terrestrial birds appeared to indicate den safety, and female giant pandas were not averse and even preferred dens with a high abundance index of rodents and terrestrial birds. The den suitability index (DSI) was a reliable tool for evaluating whether dens were suitable for female giant pandas to give birth to and rear cubs, with preference for dens with high DSI values. This study increases our understanding of the den selection criteria of female giant pandas and the main threats to the survival of their cubs, thus providing important guidance for the conservation and management of this species.

Sequence polymorphism and evolution of three cetacean MHC genes.

Sequence variability at three major histocompatibility complex (MHC) genes (DQB, DRA, and MHC-I) of cetaceans was investigated in order to get an overall understanding of cetacean MHC evolution. Little sequence variation was detected at the DRA locus, while extensive and considerable variability were found at the MHC-I and DQB loci. Phylogenetic reconstruction and sequence comparison revealed extensive sharing of identical MHC alleles among different species at the three MHC loci examined. Comparisons of phylogenetic trees for these MHC loci with the trees reconstructed only based on non-PBR sites revealed that allelic similarity/identity possibly reflected common ancestry and were not due to adaptive convergence. At the same time, trans-species evolution was also evidenced that the allelic diversity of the three MHC loci clearly pre-dated species divergence events according to the relaxed molecular clock. It may be the forces of balancing selection acting to maintain the high sequence variability and identical alleles in trans-specific manner at the MHC-I and DQB loci.

Isolation and characterization of 14 microsatellite loci for the Chevrier's field mouse (Apodemus chevrieri).

We describe the isolation and characterization of 14 microsatellite loci in the Chevrier's field mouse from genomic DNA-enriched libraries. The 14 loci were highly polymorphic with numbers of alleles per locus in 24 individuals ranging from three to 13, observed heterozygosity from 0.381 to 0.867 and expected heterozygosity from 0.448 to 0.931. All loci followed Hardy-Weinberg expectations except for CFM3, CFM10 and CFM12 loci. No significant linkage association was found among all these loci. The 14 polymorphic microsatellite loci will be useful in studying phylogeography and population genetics of the Chevrier's field mouse.

A widely applicable protocol for DNA isolation from fecal samples.

Feces are increasingly used as sources of DNA for genetic and ecological research. This paper describes a new method for isolation of DNA from animal feces. This method combines multiple purification steps, including pretreatment with ethanol and TE, an inhibitor-absorber made of starch, the CTAB method, the phenol-chloroform extraction method, and the guanidinium thiocyanate-silica method. The new method is efficient according to PCR results of 585 fecal samples from 23 species and costs much less than the commercial kits. The protocol can be tailored to the specific purpose of examining different diets of animals and can be performed with routine laboratory reagents.