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1.
Bongos ( Tragelaphus eurycerus Ogilby) were studied for 8 months in the Dzanga National Park, Central African Republic. Tracks were followed and mapped with a compass and a pedometer to study movement patterns and home range. Natural licks were shown to be central points in the home range of the bongos: they visited the licks recurrently to consume soil, but also to forage on grass and herb species, and for social reasons. Forest areas far from licks were used much less than forest areas close to licks. When a lick was visited, distances between two resting sites were longer than in the forest without lick visits, caused by a direct and straight movement from the denser forest areas toward a lick. The study area of about 150 km2 was presumably occupied by two groups of bongos. One of them seemed to split temporarily into two subgroups. Groups were not larger than 10–20 individuals. Estimated home ranges were at least 49 km2 and 19 km2 for the two groups, respectively. Estimated density in the Dzanga National Park was 0.25 bongos per km2. This study shows the importance of natural licks for the largest social forest antelope, the bongo, and provides information which is important for its future conservation.  相似文献   

2.
Wildlife and livestock in the Ngorongoro Conservation Area (NCA), Tanzania, commonly practise geophagy. We investigated the nutrient content of nine earth licks and adjacent topsoils in the NCA, and for comparative purposes, two salt pans in north-eastern Tanzania, licks in central Tanzania and a lick near Puerto Maldonado, Peru. The licks had no consistent pattern of nutrient enrichment relative to unutilized topsoils, although the Na content of licks was greater than that of the adjacent topsoils at all but one site. The three largest licks in the NCA (Gibbs Farm, Seneto and Ascent Road) were enriched relative to topsoils and global averages in Se (maximum of 4.7 mg kg−1), Co (maximum of 107 mg kg−1) and/or Mo (maximum of 7.4 mg kg−1). We suggest that licks do provide supplemental Na, but that Se, Co and/or Mo at the largest licks provide easily overlooked nutritional benefits and are perhaps the primary target for geophagy at these sites. Subsoil zones of clay deposition are likely to be enriched in various elements through illuviation or mineral precipitation from solution. Animals may use the taste of NaCl as a clue for locating such zones where they are likely to find a greater quantity of micronutrients relative to other soils. These findings have consequences for conservation and pastoralism in that these large licks may be key resources, providing micronutrients that are essential for maintaining the health and fecundity of animal as well as human populations in the region.  相似文献   

3.
Mineral licks as a sodium source for Isle Royale moose   总被引:1,自引:0,他引:1  
Summary Natural mineral licks and their use by moose (Alces alces) on Isle Royale National Park, Michigan, were studied during 1982–85. The distribution of known licks suggested that they occurred in association with glacial debris, primarily in the western portions of the island. Moose utilized mineral springs extensively during the spring-summer period, and at least 5 licks were used year-round. During summer, a pronounced diel pattern of moose visitation was apparent, with peak use occurring between 0400–0800 h. Although daytime lick use declined by late June, morning and evening use continued to be relatively high throughout the study period. Peak lick use coincided with leaf-emergence in spring. Moose continued to utilize mineral licks despite the availability of ponds containing aquatic plants. Sodium appeared to be the element attracting moose to licks where they ingest copious amounts of water. Observed sodium ingestion rates (0.35 g/min) at licks indicate that licks provide a more concentrated source of sodium compared to aquatic plants (0.023 g/min). Based on the data presented, we reject the conclusions of earlier workers that aquatic plants constitute the only significant source of sodium for Isle Royale moose.  相似文献   

4.
The Yellowstone National Park bison herd is 1 of only 2 populations known to have continually persisted on their current landscape since pre-Columbian times. Over the last century, the census size of this herd has fluctuated from around 100 individuals to over 3000 animals. Previous studies involving radiotelemetry, tooth wear, and parturition timing provide evidence of at least 2 distinct groups of bison within Yellowstone National Park. To better understand the biology of Yellowstone bison, we investigated the potential for limited gene flow across this population using multilocus Bayesian clustering analysis. Two genetically distinct and clearly defined subpopulations were identified based on both genotypic diversity and allelic distributions. Genetic cluster assignments were highly correlated with sampling locations for a subgroup of live capture individuals. Furthermore, a comparison of the cluster assignments to the 2 principle winter cull sites revealed critical differences in migration patterns across years. The 2 Yellowstone subpopulations display levels of differentiation that are only slightly less than that between populations which have been geographically and reproductively isolated for over 40 years. The identification of cryptic population subdivision and genetic differentiation of this magnitude highlights the importance of this biological phenomenon in the management of wildlife species.  相似文献   

5.
We studied responses of aboveground production, grazing by elk and the availability of eight elements (Ca, Fe, K, Mg, N, Na, P, Zn) in a Yellowstone National Park sagebrush grassland following a fire in 1992. We compared four areas of differing fire history: (1) an area burned in 1992, (2) an area burned in 1992 and 1988, (3) an area burned in 1988 and (4) an area with no recent fire history. The year after burning, graminoids produced more aboveground biomass on burned areas compared with unburned areas. Forages growing on burned soils were highly concentrated with all nutrients, except Ca, when elk grazed the site. Despite nutrient-rich forage on burned areas, elk consumed little forage in these areas. We hypothesized that elk ate less than expected in burned areas because of a large bloom of lupine (Lupinus sericeus), which may be unpalatable to elk.  相似文献   

6.
Small-scale community gradients and patterns in four grassland communities in the Serengeti National Park, Tanzania, were analyzed by detrended correspondence analysis (DCA) and percentage distance ordination (PD). The main goals of the study were (1) to describe the vegetation patterns in the communities, (2) to identify the potential underlying causes of the patterns, and (3) to rank the communities by their relative levels of patchiness. Species cover in a small number (16–32) of discontinuous plots was estimated and soils were collected. DCA successfully identified community gradients and phases of discrete mosaics, and PD identified the relative heterogeneity of the sites. Results suggested that the two most arid sites were composed of weakly or strongly differentiated vegetational mosaics and the two most mesic sites were essentially homogeneous. Termite modification of water infiltration properties of the soils and clonal growth of dominant species were identified as two factors possibly causing the mosaic vegetation patterns.  相似文献   

7.
Mineral licks--also known as "salados," "saladeros," or "collpas"--are specific sites in tropical and temperate ecosystems where a large diversity of mammals and birds come regularly to feed on soil. Although the reasons for vertebrate geophagy are not completely understood, animals are argued to obtain a variety of nutritional and health benefits from the ingestion of soil at mineral licks. We studied the temporal patterns of mineral lick use by white-bellied spider monkey (Ateles belzebuth) and red howler monkey (Alouatta seniculus) in a lowland rain forest in Amazonian Ecuador. Using camera and video traps at four different mineral licks, combined with behavioral follows of one group of spider monkeys, we documented rates of mineral lick visitation by both primate species and the relative frequency and intensity of mineral lick use by spider monkeys. On the basis of 1,612 days and 888 nights of mineral lick monitoring, we found that A. belzebuth and A. seniculus both visit mineral licks frequently throughout the year (on average ~14% of days for both species), and mineral lick visitation was influenced by short-term environmental conditions (e.g. sunny and dry weather). For spider monkeys, the area surrounding the lick was also the most frequently and most intensively used region within the group's home range. The fact that spider monkeys spent long periods at the lick area before coming to the ground to obtain soil, and the fact that both species visited the lick preferentially during dry sunny conditions (when predator detectability is presumed to be relatively high) and visited simultaneously more often than expected by chance, together suggest that licks are indeed perceived as risky areas by these primates. We suggest that howler and spider monkeys employ behavioral strategies aimed at minimizing the probability of predation while visiting the forest floor at risky mineral lick sites.  相似文献   

8.
Chemical and physical data from analyses of soil samples of Kalahari Sand deposits in Wankie National Park, Rhodesia, show that salt licks created and used by elephant are characterized by high concentrations of water soluble sodium. Soils with concentrations of calcium, magnesium and potassium in, for instance, termite mounds are used as licks only in regions where soluble sodium is not present in quantity in the soil. Shallow steep-sided salt licks are dug out by elephants with their forefeet during the dry season. Elephant dung is deposited in large quantities on and near salt licks at that season. A brown colour is present in aqueous extracts of salt-lick soils and is likely to consist of sodium salts of humic derivatives of elephant faeces or urine. Rainwater gathering in salt licks in the wet season has an equivalent brown colour and a high sodium content. Similar soil regions rich in sodium but not used as licks have no brown colouration in the soil extract. This brown soluble humic derivative may enable the elephant to detect the salt lick by smell. Licks appear to be important in the social life of the elephant populations. The intensity of present usage of salt licks by elephants is leading to localized soil erosion which will eventually result in the filling in of many clay pans with coarser sands.  相似文献   

9.
Many ungulates are reported to use natural or artificial licks with seasonal patterns around the world. From December 2016 to August 2017, we used infrared camera to record the use of artificial licks in wild sika deer (Cervus nippon) in Zhejiang Qingliangfeng National Nature Reserve, China. We explored the daily rhythm, seasonal pattern and sex difference in lick utilization. In total, 12,043 videos and 22,901 pictures were collected. Our results showed that: (1) the lick visiting frequency was higher at night than that during daytime; (2) the difference in lick visiting frequency between females and males disappeared after taking into account of sex ratio; (3) the lick duration peaked in April during a year. These findings suggested that there were clear daily rhythm and seasonal pattern of lick use in sika deer. Seasonal change in lick use intensity was consistent with our prediction. These variations in lick use might be driven by both the physiological needs of the mineral elements in different life stages and the seasonal changes in climate and food. The reserve management authority should pay more attention to the supplement of licks in spring and summer to fulfill animal’s physiological needs.  相似文献   

10.
Fungi from geothermal soils in Yellowstone National Park   总被引:1,自引:0,他引:1  
Geothermal soils near Amphitheater Springs in Yellowstone National Park were characterized by high temperatures (up to 70 degrees C), high heavy metal content, low pH values (down to pH 2.7), sparse vegetation, and limited organic carbon. From these soils we cultured 16 fungal species. Two of these species were thermophilic, and six were thermotolerant. We cultured only three of these species from nearby cool (0 to 22 degrees C) soils. Transect studies revealed that higher numbers of CFUs occurred in and below the root zone of the perennial plant Dichanthelium lanuginosum (hot springs panic grass). The dynamics of fungal CFUs in geothermal soil and nearby nongeothermal soil were investigated for 12 months by examining soil cores and in situ mesocosms. For all of the fungal species studied, the temperature of the soil from which the organisms were cultured corresponded with their optimum axenic growth temperature.  相似文献   

11.
The Northern Rocky Mountain Wolf Recovery plan proposed reintroduction of Canis lupus (gray wolf) to Yellowstone National Park and central Idaho as part of a wolf restoration plan for the northern Rocky Mountains of the United States. Strong opposition from some factions within the region forestalled the action for two decades. An environmental impact statement, conducted in 1992–1994 with extensive public input, culminated in a proposal to reintroduce wolves designated as “non-essential—experimental” under Section 10 (j) of the federal Endangered Species Act. This approach, approved by the Secretary of the Interior in 1994, provided for wolf restoration while allowing management flexibility to deal with concerns of the local public. A reintroduction plan was developed in the summer and fall of 1994. Acquiring, holding, transporting, and releasing suitable wolves for reintroduction presented a myriad of technical and logistical challenges that required effective planning and coordination by all participants. In January 1995, 29 wolves were captured in Alberta and transported to Yellowstone National Park (14) and central Idaho (15). Idaho wolves were freed immediately upon arrival; Yellowstone wolves (three family groups) were held in acclimation pens in the park until late March. Most Idaho wolves traveled extensively within the area intended for them, averaging 82 km net distance away from release sites after 5 months (range = 30–220 km), and three male-female pairs formed by July. After 5 months in the wild, at least 13 of 15 Idaho-released wolves were alive within the intended area, as were 13 of 14 Yellowstone wolves; one wolf was known to have been illegally killed in each area. No livestock were killed. Wolves released into Yellowstone Park continued to live as packs, stayed closer to their release sites (x = 22 km at end of June), and settled into home ranges; two packs produced a total of nine pups. The progress of the reintroduction program in its first year far exceeded expectations. Reintroductions of about 15 wolves to each area for 2–4 more years are scheduled, but the project may be shortened because of early successes. Future reintroduction planners can expect sociocultural issues to pervade the effort, but they can be optimistic that, from a biological standpoint, reintroduction of wolves has strong potential as a restoration technique.  相似文献   

12.
Geothermal soils near Amphitheater Springs in Yellowstone National Park were characterized by high temperatures (up to 70°C), high heavy metal content, low pH values (down to pH 2.7), sparse vegetation, and limited organic carbon. From these soils we cultured 16 fungal species. Two of these species were thermophilic, and six were thermotolerant. We cultured only three of these species from nearby cool (0 to 22°C) soils. Transect studies revealed that higher numbers of CFUs occurred in and below the root zone of the perennial plant Dichanthelium lanuginosum (hot springs panic grass). The dynamics of fungal CFUs in geothermal soil and nearby nongeothermal soil were investigated for 12 months by examining soil cores and in situ mesocosms. For all of the fungal species studied, the temperature of the soil from which the organisms were cultured corresponded with their optimum axenic growth temperature.  相似文献   

13.
Nutrient dynamics of large grassland ecosystems possessing abundant migratory grazers are poorly understood. We examined N cycling on the northern winter range of Yellowstone National Park, home for large herds of free-roaming elk (Cervus elaphus) and bison (Bison bison). Plant and soil N, net N mineralization, and the deposition of ungulate fecal-N were measured at five sites, a ridgetop, mid-slope bench, steep slope, valley-bottom bench, and riparian area, within a watershed from May, 1991 to April, 1992.Results indicated similarities between biogeochemical properties of Yellowstone grassland and other grassland ecosystems: (1) landscape position and soil water affected nutrient dynamics, (2) annual mineralization was positively related to soil N content, and (3) the proportion of soil N mineralized during the year was negatively related to soil C/N.Grazers were a particularly important component of the N budget of this grassland. Estimated rates of N flow from ungulates to the soil ranged from 8.1 to 45.6 kg/ha/yr at the sites (average = 27.0 kg/ha/yr), approximately 4.5 times the amount of N in senescent plants. Rates of nitrogen mineralization for Yellowstone northern range grassland were higher than those measured in other temperate grassland ecosystems, possibly due to grazers promoting N cycling in Yellowstone.  相似文献   

14.
Water quality of streams in the Great Smoky Mountains National Park   总被引:5,自引:2,他引:5  
Water samples from streams in the Great Smoky Mountains National Park were analyzed for 16 physical, chemical, and bacteriological water quality parameters. Bacterial densities, pH, alkalinity, turbidity, and concentrations of Na, K, and Si were found to be higher in the low elevations than in the high. Nitrate concentrations increased with increasing elevation. Watersheds which had been logged prior to the establishment of the park had significantly lower stream water nitrate concentrations than unlogged watersheds at similar elevations. Bedrock geology was found to influence pH, alkalinity, conductivity, hardness, and concentrations of Na, K, Ca, Mg, and Si. The seasonal pattern for most water quality parameters was for higher concentrations or values in the summer and lower in the winter. Discharge was highest in the winter and spring and lowest in the summer and fall. Nitrate concentrations were highest in the late winter and early spring and lowest in the fall. Storm events often caused large changes in water quality.  相似文献   

15.
Spider monkeys and howler monkeys are the only Neotropical primates that eat soil from mineral licks. Not all species within these genera visit mineral licks, and geophagy has been restricted to populations of Ateles belzebuth belzebuth,Ateles belzebuth chamek and Alouatta seniculus in western Amazonian rainforests. With the aid of a camera trap we studied the visitation patterns of a group of brown spider monkeys (Ateles hybridus) to a mineral lick at Serrania de Las Quinchas, in Colombia. Spider monkeys visited the lick frequently throughout the year, with a monthly average of 21.7 ± 7.2 visits per 100 days of camera trapping (n = 14 months). Spider monkeys visited the mineral lick almost always on days with no rain, or very little (<3 mm) rain, suggesting that proximate environmental variables might determine spider monkeys' decisions to come to the ground at the licks. This study expands the geographical occurrence of mineral lick use by spider monkeys providing additional data for future assessments on the biogeographical correlates of mineral lick use by platyrrhines.  相似文献   

16.
Scavenging by large‐bodied vertebrates is observed in many ecosystems but has rarely been quantified. Here we document the timing and order of scavenger arrival at 639 cheetah kills in Serengeti National Park, Tanzania, focusing on ecological and heterospecific factors that may impact detectability of carcasses. We found that small‐, medium‐ and large‐sized vultures, jackals, spotted hyaenas and lions were more likely to be present at the carcasses of large‐bodied than small‐bodied prey. Lions and spotted hyaenas were less likely to locate kills in tall grass; medium‐sized vultures were likely to arrive before both large‐ and small‐sized vultures. Spotted hyaenas and vultures were likely to be present at kills simultaneously. Despite numerous anecdotal accounts, we did not find that hyaenas use alighting vultures as a means of locating food. Our findings show that environmental variables and other scavenger species strongly influence scavenger arrival at carcasses in this ecosystem.  相似文献   

17.
The breeding ecology of the Kori Bustard Ardeotis kori strunthiunculus was studied in the plains of the Serengeti National Park, Tanzania in 2014 and 2015. Random transects were used to search for male courtship displays, nests, chicks and subadults. GPS satellite collars were used to locate nesting females. Linear regression analyses and post hoc tests were used to determine the predictors that contributed most to the variation of the dependent variables (courtship display, nest, chicks and subadults). The results indicate that courtship behaviour peaks during the short dry and short rainy season before the peaks in nests and chicks. The highest nest frequency was found in short grass habitats. Female Kori Bustard may undergo repeated nestings within a single breeding season. The adult sex ratio was female skewed during the breeding season. The Kori Bustard breeding season in the Serengeti plains is relatively long, lasting for almost nine months, and taking place during all seasons except for the long dry season. We recommend that management authorities conduct assessments of Kori Bustard recruitment as well as habitat suitability in the Serengeti ecosystem to develop future conservation strategies.  相似文献   

18.
Mycobacterium parascrofulaceum was found in Norris Geyser Basin, Yellowstone National Park, in a system composed of two acidic (pH 3.0) springs with temperatures between 56 degrees C at the source and 40 degrees C at the confluence of both springs. Growth and survival assays at 56 degrees C for 60 days were performed, confirming the origin of the strain.  相似文献   

19.
Microorganisms are largely responsible for soil nutrient cycling and energy flow in terrestrial ecosystems. Although soil microorganisms are affected by topography and grazing, little is known about how these two variables may interact to influence microbial processes. Even less is known about how these variables influence microorganisms in systems that contain large populations of free-roaming ungulates. In this study, we compared microbial biomass size and activity, as measured by in situ net N mineralization, inside and outside 35- to 40-year exclosures across a topographic gradient in northern Yellowstone National Park. The objective was to determine the relative effect of topography and large grazers on microbial biomass and nitrogen mineralization. Microbial C and N varied by almost an order of magnitude across sites. Topographic depressions that contained high plant biomass and fine-textured soils supported the greatest microbial biomass. We found that plant biomass accurately predicted microbial biomass across our sites suggesting that carbon inputs from plants constrained microbial biomass. Chronic grazing neither depleted soil C nor reduced microbial biomass. We hypothesize that microbial populations in grazed grasslands are sustained mainly by inputs of labile C from dung deposition and increased root turnover or root exudation beneath grazed plants. Mineral N fluxes were affected more by grazing than topography. Net N mineralization rates were highest in grazed grassland and increased from dry, unproductive to mesic, highly productive communities. Overall, our results indicate that topography mainly influences microbial biomass size, while mineral N fluxes (microbial activity) are affected more by grazing in this grassland ecosystem. Received: 4 June 1997 / Accepted: 16 December 1997  相似文献   

20.
Microbiological and geochemical surveys were conducted at three hot springs (Obsidian Pool, Sylvan Spring, and ‘Bison Pool’) in Yellowstone National Park (Wyoming, USA). Microbial community structure was investigated by polymerase chain reaction (PCR) amplification of 16S rRNA gene sequences from DNA extracted from sediments of each hot spring, followed by molecular cloning. Both bacterial and archaeal DNA was retrieved from all samples. No Euryarchaea were found, but diverse Crenarchaea exist in all three pools, particularly affiliating with deep‐branching, but uncultivated organisms. In addition, cloned DNA affiliating with the Desulphurococcales and Thermoproteales was identified, but the distribution of taxa differs in each hot spring. The bacterial community at all three locations is dominated by members of the Aquificales and Thermodesulfobacteriales, indicating that the ‘knallgas’ reaction (aerobic hydrogen oxidation) may be a central metabolism in these ecosystems. To provide geochemical context for the microbial community structures, energy‐yields for a number of chemolithoautotrophic reactions are provided for >80 sampling sites in Yellowstone, including Obsidian Pool, Sylvan Spring, and ‘Bison Pool’. This energy profile shows that the knallgas reaction is just one of many exergonic reactions in the Yellowstone hot springs, that energy‐yields for certain reactions can vary substantially from one site to the next, and that few of the demonstrated exergonic reactions are known to support microbial metabolism.  相似文献   

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