scholarly journals Antelope space-use and behavioural responses to varying anthropogenic influences may permit long-term persistence in a highly human-dominated landscape

2021 ◽  
Author(s):  
Rohit Raj Jha ◽  
Kavita Isvaran

The only means of conserving a species or a habitat in a human-dominated landscape is through promoting coexistence while minimizing conflict. To achieve this, it is vital to understand how wildlife are impacted by direct and indirect human activities. Such information is relatively rare from areas with high human densities. To investigate how animals respond to altered ecological conditions in human-dominated landscapes, we focussed on a wild herbivore of conservation concern in Krishnasaar Conservation Area (KrCA) in Nepal. Here, blackbuck Anticope cervicapra, a generalist grazer, lives in refugia located in a growing human population. We studied the impacts of humans on habitat-use and behaviour of blackbuck. We laid 250 x 250 m grid cells in the entire KrCA and carried out indirect sign surveys with three replications for habitat-use assessment. We observed herds of blackbuck for 89 hours in different possible habitat types, location and time of the day using scan sampling methods. Our habitat-use survey showed that habitats under intensive human use were hardly used by blackbuck, even when high-quality forage was available. In areas with low levels of human activity, natural risk factors, primarily habitat openness, was the major predictor of habitat-use. Interestingly, livestock presence positively influenced habitat-use by blackbuck. Blackbuck were substantially more vigilant when they were in forest than in grassland, again indicating an influence of risk. Overall, blackbuck appear to be sensitive to risk associated with both natural and anthropogenic factors. Our findings have direct implications for managing human-wildlife interactions in this landscape, specifically regarding strategies for livestock grazing in habitats highly used by blackbuck and concerning predictions of how changing land-use will impact long-term persistence of blackbuck. Our work suggests that wild herbivores may be able to persist in landscapes with high human densities so long as there are refuges where levels of human activity are relatively low.

Oryx ◽  
2018 ◽  
Vol 54 (3) ◽  
pp. 421-428 ◽  
Author(s):  
Gopal Khanal ◽  
Laxman Prasad Poudyal ◽  
Bishnu Prasad Devkota ◽  
Rishi Ranabhat ◽  
Per Wegge

AbstractThe snow leopard Panthera uncia is globally threatened and reliable information on its abundance, distribution and prey species is a prerequisite for its conservation. In October–November 2014 we assessed the distribution of the snow leopard in the recently established Api Nampa Conservation Area in the Nepal Himalayas. Within selected blocks we conducted sign surveys and counted the number of bharal Pseudois nayaur, its principal wild prey, along transects totalling 106 km. We recorded 203 putative snow leopard signs at an encounter rate of 1.91 signs/km. Generalized linear models of the number of signs detected per transect showed that elevation had a positive influence and human activities a negative influence on sign encounter rate; prey abundance had only a weak positive influence on sign encounter rate. Within the effectively surveyed area of c. 200 km2, we counted 527 bharal at an estimated density of 2.28 animals/km2. Recruitment of bharal was low, estimated at 48 kids/100 adult females, most likely a result of poor or overgrazed rangeland. We estimate the total number of bharal in this conservation area to be > 1,000, a prey base that could sustain 6–9 snow leopards. Based on our field observations, we identified human disturbance and habitat degradation associated with extraction of non-timber forest products, livestock grazing, and poaching as the main threats to the snow leopard. Standardized sign surveys, preferably supplemented by sampling with remote cameras or with genetic analysis of scats would provide robust baseline information on the abundance of snow leopards in this conservation area.


2015 ◽  
Vol 26 ◽  
pp. 224-229
Author(s):  
Suprabha Ban ◽  
Nanda Bahadur Singh

The seasonal habitat use pattern of Blackbuck in Blackbuck Conservation Area (BCA) was studied by the division of the realized habitat of Blackbuck (1.74 sq. km) into three blocks A, B and C. Direct count method and indirect count methods were used for the study of seasonal habitat use pattern of the animal. It was observed that block A was mostly used by the animal followed by block C and block B respectively. The study focuses in the implementation of controlled and rotational livestock grazing in BCA as an effective wildlife management tool.J. Nat. Hist. Mus. Vol. 26, 2012: 224-229


2020 ◽  
Vol 639 ◽  
pp. 169-183
Author(s):  
P Matich ◽  
BA Strickland ◽  
MR Heithaus

Chronic environmental change threatens biodiversity, but acute disturbance events present more rapid and immediate threats. In 2010, a cold snap across south Florida had wide-ranging impacts, including negative effects on recreational fisheries, agriculture, and ecological communities. Here, we use acoustic telemetry and historical longline monitoring to assess the long-term implications of this event on juvenile bull sharks Carcharhinus leucas in the Florida Everglades. Despite the loss of virtually all individuals (ca. 90%) within the Shark River Estuary during the cold snap, the catch per unit effort (CPUE) of age 0 sharks on longlines recovered through recruitment within 6-8 mo of the event. Acoustic telemetry revealed that habitat use patterns of age 0-2 sharks reached an equilibrium in 4-6 yr. In contrast, the CPUE and habitat use of age 3 sharks required 5-7 yr to resemble pre-cold snap patterns. Environmental conditions and predation risk returned to previous levels within 1 yr of the cold snap, but abundances of some prey species remained depressed for several years. Reduced prey availability may have altered the profitability of some microhabitats after the cold snap, leading to more rapid ontogenetic shifts to marine waters among sharks for several years. Accelerated ontogenetic shifts coupled with inter-individual behavioral variability of bull sharks likely led to a slower recovery rate than predicted based on overall shark CPUE. While intrinsic variation driven by stochasticity in dynamic ecosystems may increase the resistance of species to chronic and acute disturbance, it may also increase recovery time in filling the diversity of niches occupied prior to disturbance if resistive capacity is exceeded.


The Holocene ◽  
2016 ◽  
Vol 27 (5) ◽  
pp. 651-664 ◽  
Author(s):  
Krystyna Milecka ◽  
Grzegorz Kowalewski ◽  
Barbara Fiałkiewicz-Kozieł ◽  
Mariusz Gałka ◽  
Mariusz Lamentowicz ◽  
...  

Wetlands are very vulnerable ecosystems and sensitive to changes in the ground water table. For the last few thousand years, hydrological balance has also been influenced by human activity. To improve their cropping features, drainage activity and fertilizing were applied. The drainage process led to an abrupt change of environment, the replacement of plant communities and the entire ecosystem. The problem of carbon sequestration is very important nowadays. A higher accumulation rate is related to higher carbon accumulation, but the intensity of carbon sequestration depends on the type of mire, habitat, and climatic zone. The main aim of this article was an examination of the changes in poor-fen ecosystem during the last 200 years in relation to natural and anthropogenic factors, using paleoecological methods (pollen and macrofossils). The second aim was a detailed investigation of the sedimentary record to aid our understanding of carbon sequestration in the poor fen of temperate zone. This case study shows that fens in temperate zones, in comparison with boreal ones, show higher carbon accumulation rates which have been especially intensive over the last few decades. To reconstruct vegetation changes, detailed palynological and macrofossil analyses were done. A 200-year history of the mire revealed that it was influenced by human activity to much degree. However, despite the nearby settlement and building of the drainage ditch, the precious species and plant communities still occur.


2021 ◽  
pp. 101377
Author(s):  
Anant Deshwal ◽  
Pooja Panwar ◽  
Joseph C. Neal ◽  
Matthew A. Young

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Niloufar Nouri ◽  
Naresh Devineni ◽  
Valerie Were ◽  
Reza Khanbilvardi

AbstractThe annual frequency of tornadoes during 1950–2018 across the major tornado-impacted states were examined and modeled using anthropogenic and large-scale climate covariates in a hierarchical Bayesian inference framework. Anthropogenic factors include increases in population density and better detection systems since the mid-1990s. Large-scale climate variables include El Niño Southern Oscillation (ENSO), Southern Oscillation Index (SOI), North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO), Arctic Oscillation (AO), and Atlantic Multi-decadal Oscillation (AMO). The model provides a robust way of estimating the response coefficients by considering pooling of information across groups of states that belong to Tornado Alley, Dixie Alley, and Other States, thereby reducing their uncertainty. The influence of the anthropogenic factors and the large-scale climate variables are modeled in a nested framework to unravel secular trend from cyclical variability. Population density explains the long-term trend in Dixie Alley. The step-increase induced due to the installation of the Doppler Radar systems explains the long-term trend in Tornado Alley. NAO and the interplay between NAO and ENSO explained the interannual to multi-decadal variability in Tornado Alley. PDO and AMO are also contributing to this multi-time scale variability. SOI and AO explain the cyclical variability in Dixie Alley. This improved understanding of the variability and trends in tornadoes should be of immense value to public planners, businesses, and insurance-based risk management agencies.


2002 ◽  
Vol 55 (4) ◽  
pp. 400 ◽  
Author(s):  
Joseph M. Navarro ◽  
Dee Galt ◽  
Jerry Holechek ◽  
Jim McCormick ◽  
Francisco Molinar

Oryx ◽  
2013 ◽  
Vol 48 (3) ◽  
pp. 394-401 ◽  
Author(s):  
Edward Okot Omoya ◽  
Tutilo Mudumba ◽  
Stephen T. Buckland ◽  
Paul Mulondo ◽  
Andrew J. Plumptre

AbstractDespite > 60 years of conservation in Uganda's national parks the populations of lions and spotted hyaenas in these areas have never been estimated using a census method. Estimates for some sites have been extrapolated to other protected areas and educated guesses have been made but there has been nothing more definitive. We used a lure count analysis method of call-up counts to estimate populations of the lion Panthera leo and spotted hyaena Crocuta crocuta in the parks where reasonable numbers of these species exist: Queen Elizabeth Protected Area, Murchison Falls Conservation Area and Kidepo Valley National Park. We estimated a total of 408 lions and 324 hyaenas for these three conservation areas. It is unlikely that other conservation areas in Uganda host > 10 lions or > 40 hyaenas. The Queen Elizabeth Protected Area had the largest populations of lions and hyaenas: 140 and 211, respectively. It is estimated that lion numbers have declined by 30% in this protected area since the late 1990s and there are increasing concerns for the long-term viability of both species in Uganda.


2018 ◽  
Vol 29 (2) ◽  
Author(s):  
N. O. Roshchyna

In this article, the current and former distribution of higher aquatic vegetation has been analyzed for floodplain lakes, arenas lakes and third terraces lakes in the valleys of large and medium North-Steppe Dnieper rivers. The article is devoted to the current state analysis of the higher aquatic vegetation at North-Steppe Dnieper lakes, its dynamics over a long-term period, as well as the determination of the nature and extent of anthropogenic-climatic changes in vegetation. Anthropogenic influence is a major threat to the development and functioning of most aquatic ecosystems. Since the twentieth century, it has been intensified by trends to long-term climate changes, which are also largely result of human activity. Increasing temperature of the winter season does not contribute to snow accumulation. Reduction of snow accumulation (frequent thaws during the winter), regulation of river flow (formation of a reservoirs cascade and ponds) and accumulation of melt water in artificial reservoirs led to the smoothing of the peak of the spring flood. Thus, the factor that provided spring washing of floodplain lakes, limited their overgrowing by air-water vegetation and their waterlogging disappeared. The anthropogenic factors that influence negatively include: intensification of agriculture, plowing of coastal areas, unreasonable land reclamation, overgrazing, development of transport and engineering infrastructure, urbanization, recreation, and chemical pollution. The presented data was obtained on the basis of processing our own research materials of 2009–2018 and literary and archival materials analysis (the herbarium of the Dnipropetrovs’k National University and the archive of the Research Institute of Biology). Natural Northern Steppe Dnieper lakes are located mainly in river valleys, so the study area was conventionally divided into sections: the large river valley (Dnieper) and the middle rivers valleys (Samara and Orel). Three ecological groups of macrophytes were reviewed and compared: hydatofites (submerged species), pleistophytes (species with floating leaves) and helophytes (air-water species). The vegetation of Dnieper floodplain lakes practically did not change for all three formation groups. The number of immersed plants communities within the floodplains of medium-sized rivers has decreased by three. The pleistophytes and helophytes associations decreased to fragments of associations. The lakes vegetation within the sandy Dnieper terrace practically did not change for all three formation groups. The submerged lakes plants associations within the sandy medium-sized rivers terraces have been reduced by two. As part of the lakes vegetation on the Dnipro saline terraces, fragments of associations of the two species are considered extinct. A new association of southern adventive species Ruppia maritima L. has appeared within the limits of the middle rivers saline terrace. Changes in higher aquatic vegetation are characteristic of all types of lakes. Changes occur in the direction of crowding out higher aquatic vegetation communities by airborne plant communities. The consequence of the anthropogenic-climatic transformation of aquatic ecosystems is increased mineralization, siltation, and, as a result, intensive overgrowing of lakes by aboriginal and adventive species with a wide ecological amplitude (replacement of sensitive to environmental changes species).


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