Is it acne or rosacea? One of the most common signs of rosacea, bumps, and pimples, is also one of the most common causes of confusion about the skin condition. Added Title Size RTS S L DL Subcat; : Sandy.Wexler.2017.HDRip.XviD.AC3-EVO Winter diet and food selection of the Black- necked Crane Grus nigricollis in Dashanbao, Yunnan, China . The cranes migrate short distances to winter in the lower altitude (primarily 2,0. Yunnan–Guizhou Plateau (Harris & Mirande, 2. Through telemetry and banding data, it has become clear that the birds using the Eastern migratory route (in the following referred to as the Eastern Black- necked Cranes) breed in northern Sichuan and southern Gansu provinces and mainly winter in northeast Yunnan and southwest Guizhou (Li & Li, 2. Qian et al., 2. 00. More than 5. 0% of the wild populations of this species are currently suffering due to significant habitat destruction resulting from grassland degeneration (Li & Li, 2. Yunnan. Food is the factor determining the long- term survival of Black- necked Crane (Liu et al., 2. Thus, understanding the Black- necked Crane’s dietary habits, food preferences, and the associated factors will facilitate the development of effective conservation plans for the protection of this vulnerable species. Determining the dietary composition of wild birds is essential for understanding how the animals interact with their habitats and consequently for identifying their preferred food types (Baubet, Bonenfant & Brandt, 2. Their late discovery and remote range led to a late start in research pertaining to Black- necked Crane’s feeding habits (Harris & Mirande, 2. To this point, research surrounding the Black- necked Crane’s diet has included quantitative studies on various types of domestic and wild plant foods (Li & Nie, 1. Bishop & Li, 2. Liu et al., 2. 01. Han, 1. 99. 5; Hu et al., 2. Li & Li, 2. 00. Liu, Yang & Zhu, 2. Nonetheless, there remains a lack of synthetic analyses or comparative data regarding the proportions of domestic food crops, animal- matter, and wild plants consumed by the Blacked- necked Crane during the winter. Until now, fecal microhistological analysis has been the only method used to identify plant material consumed by wintering Black- necked Cranes (Li & Nie, 1. Liu et al., 2. 01. These studies did not mention the consumption of animal- based foods due to the need for alternative methods to collect this data (Liu, Yang & Zhu, 2. Generally, fecal analysis can create a bias due to the high variability in digestibility of different food items (Redpath et al., 2. Thus, we chose video recording as an alternative method to better understand the food selection of Black- necked Cranes. This method provided a simple, minimally invasive manner to directly observe the feeding behavior of the threatened bird species in order to estimate their dietary composition (Newton, 1. Price, 1. 98. 7; Yoshikawa & Osada, 2. Previous studies suggest that variations in temperature may impact food availability (Kushlan, 1. Stapanian, Smith & Finck, 1. As mentioned by Alonso, Alonso & Bautista (1. Common Cranes Grus grus by increasing foraging costs due to changes in soil properties. Likewise, temperature is an important correlate of insect activity, further affecting the invertebrate- feeding birds. Higher temperatures are associated with more frequent droughts and dry soils (Martin, 1. Thus, both affect the degree of insect activity (Mc. Collogh, Hayes & Bryson, 1. Dowdy, 1. 93. 7; Zhou et al., 2. Considering this information, we considered that the temperature changes would influence the attributes of available foraging sites, affecting food availability and food selection. The goal of this research was to better understand factors influencing Black- necked Cranes selection of different feeding habitats during the winter. This information may facilitate the development of strategies to protect the Eastern Black- necked Crane, whose largest population winters in their most important wintering sites in the Dashanbao National Nature Reserve on the Yunnan–Guizhou Plateau (Li & Yang, 2. Qian et al., 2. 00. In this report, we provided a quantitative and comprehensive assessment of the cranes’ wintering diet, which included domestic food crops, animal- based foods, and wild plants. We analyzed the cranes’ diet composition, food selection, and any correlation between environmental factors, food availability, and food selection. Methods. Ethics statement. Our research on Black- necked Cranes in Dashanbao National Nature Reserve was approved by the Chinese Wildlife Management Authority and conducted under Law of the People’s Republic of China on the Protection of Wildlife (August 2. Field permit. The Administration of Zhao. Tong Forestry Bureau approved our study on behavior observation and food availability sampling in the research plot in Dashanbao National Nature Reserve (IDZTL2. Study site. Dashanbao National Nature Reserve (hereafter referred to as Dashanbao Reserve, 2. Ramsar Convention on Wetlands. The Dashanbao Reserve is considered an important habitat for Black- necked Cranes, as well as other wintering water birds. It is also known for its upland wetland ecosystem (Zhong & Dao, 2. The study area covers 1. During winter months, frequent days of sustained freezing temperatures can be expected from December to January. The mean temperature for January is . The mean annual temperature is 6. The mean annual precipitation is 1,1. Li & Zhong, 2. Figure 1: Map of the Dashanbao National Nature Reserve (thin black line), showing the location of our study areas. The red dot at the upper right designates the location of the Reserve within China. Circles indicate sites where we recorded cranes foraging. Stars indicate the sites of food availability sampling. Thick lines indicate the transects. Dahaizi Reservoir (blue) and Tiaodunhe Reservoir (yellow) are indicated. Thin blue lines indicate smaller water bodies. A total of c. 1,2. Black- necked Cranes winter in the Dashanbao Reserve every year, feeding on agricultural farmlands, as well as wild grasslands (Kong, 2. For the purposes of this study, supplemental feeding by humans was ignored because only c. Kong et al., 2. 01. Farmland included fields of cereal (Avena sativa and Fagopyrum tataricum), potatoes (Solanum tuberosum) and turnip (Brassica rapa var. Local farming uses a 3- year rotation system, in which cereal is grown one year, followed by two years of potato or turnip, and then back to cereal. Thus, a mosaic of patches of cereal, potato and turnip characterizes the farmland, with each occupying about the same surface area each year. Wild grasslands were comprised of meadows with minimal water (Kong et al., 2. Dactylis glomerata), bluegrass (Poa annua), Leontopodium, Trifolium, Pterospermum heterophyllum, Pedicularis densispica, Luzula multiflora, Hemiphragma heterophyllum (Kuang et al., 2. The cranes have been reported to forage on Pedicularis, Stellaria, Polygonatum and Veronica (Kong et al., 2. Liu et al., 2. 01. The study area covered most of the foraging sites of Black- necked Cranes. Bird observations. Field data were collected from November 2. February 2. 01. 5 in the Dashanbao Reserve. Since Black- necked Cranes are highly vigilant and the landscape of the Dashanbao Reserve consists of rolling hills and valleys, we were unable to adequately observe the flocks from our vehicles along the main road in the Dashanbao Reserve and we had to walk along smaller roads. Therefore, we selected three transect routes crossing the mountain ridge of the reserve at two sites which housed the largest flocks of cranes according to the reserve staff’s experience and the suggestions from previous research in October 2. Kong et al., 2. 01. Fig. The majority of cranes arrived in early November and remained feeding in Dashanbao Reserve until early March. We observed cranes for three days every week for 1. November and the end of February. In both years, we missed one week due to severe weather. We videotaped the birds for 5- min intervals each along all transect routes. We walked transects once per day and switched direction of travel on subsequent days. During this time, the cranes were undisturbed and at a maximum distance of 8. Based on personal observation, the cranes would startle and flee their feeding site when observed from a distance of less than 6. Thus, most sightings were between 6. For videotaping we chose cranes at random from a within the total number of birds in a flock. This resulted in observations of 5. A total of 5. 05 good quality, 5- min videos were recorded, ensuring sufficient clarity to accurately differentiate among all the consumed food types. For this study, poor quality recordings and those lasting less than 5 min were discarded. A Canon Power. Shot SX3. IS digital camera with a 3. Food types were classified into 3 categories: (1) domestic crops (including: a. Videorecordings of foraging cranes were examined in slow motion to quantify number of pecks per 5- min interval. Every video was watched at least three times to confirm accurate identification of the food types consumed by the feeding crane. Depending on the types of food being eaten, and the peck frequency, four different types of feeding patterns were identified: (1) high pecking frequency and ingestion of all the target food quickly in farmland. This pattern was used primarily for grain on the surface of the ground (see Videos S1 and S2). Since tubers are too bulky for cranes to swallow, they peck at them repeatedly, swallowing smaller pieces, until the item is completely consumed. This behavior facilitates visual identification of tuber consumption. This pattern leaves an obvious disturbance of the turf that can be used for identification (see Figs. We distinguished this from foraging on grains via a lower pecking frequency and slower swallowing movements (see Video S6, Fig. We recorded the numbers of pecks for each food type. When there was more than one food type in a 5- min recording, we recorded the number of pecks for each type separately. Food availability.
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