22 research outputs found
The importance of integrating behavioral ecology into experimental design when censusing Himalayan Galliformes.
Recovery of the snow leopard in Sagarmatha (Mt. Everest) National Park: effects on main prey
Consequences of predation may be particularly
heavy on small populations of herbivores, especially if they
are threatened with extinction. Over the 2006–2010 period, we
documented the effects of the spontaneous return of the endangered
snow leopard on the population of the vulnerable
Himalayan tahr. The study area was an area of central
Himalaya where this cat disappeared c. 40 years before, because
of persecution by man. Snow leopards occurred mainly
in areas close to the core area of tahr distribution. Tahr was the
staple (56.3 %) of snow leopards. After the arrival of this cat,
tahr decreased by more than 2/3 from 2003 to 2010 (mainly
through predation on kids). Subsequently, the density of snow
leopards decreased by 60%from2007 to 2010. The main prey
of snow leopards in Asia (bharal, marmots) were absent in our
study area, forcing snow leopards to specialize on tahr. The
restoration of a complete prey spectrum should be favoured
through reintroductions, to conserve large carnivores and to
reduce exploitation of small populations of herbivores, especially
if threatened
Mating dominance amongst male Himalayan tahr: Blonds do better
In ungulates, rank order is determined by differences in weight, body size, weapon size and age. In the Caprini tribe (Bovidae: Caprinae), adult male Himalayan tahr are unique to show different coat colours, but no sexual dimorphism in weapons. A highly significant correlation between hair colour and rank order was found during the rut: males with a lighter coloured ruff dominated over darker ruffed ones, in both aggressive interactions and access to oestrus females. We studied colour-based dominance in relation to weight, age and testosterone levels, which establish the social rank in most ungulates. No differences inweight and testosterone concentrationswere found between adult male colour classes, but males with paler ruffs were significantly younger than darker adult males. The distribution of physical traumas from fights confirmed that younger, lighter-coloured males had a higher rank than older, darker males, a pattern which is unusual amongst ungulates. Coat colour seems to work as a signal of rank in male–male aggressive interactions and it changes according to age, whereas the relevant physiological determinants deserve further research. Intrasexual male competition has not changed weapon size or shape in the Himalayan tahr, but ruff colours are apparently used to signal rank and dominance. Colour patterns of adult malesmay then be homologous to ritualisedweapons, apparently being a unique feature of male tahr amongst mammals
Common and snow leopards share prey, but not habitats: competition avoidance by large predators?
Resource exploitation and behavioural interference underlie competition among
carnivores. Competition is reduced by specializing on different prey and/or spatiotemporal
separation, usually leading to different food habits. We predicted that
two closely related species of large cats, the endangered snow leopard and the
near-threatened common leopard, living in sympatry, would coexist through
habitat separation and exploitation of different prey species. In central Himalaya,
we assessed (2006–2010) habitat and diet overlap between these carnivores. The
snow leopard used grassland and shrubland, whereas the common leopard
selected forest. Contrary to our prediction, snow leopard and common leopard
preyed upon similar wild (Himalayan tahr, musk deer) and domestic species (Bos
spp., dogs). Dietary overlap between snow leopard and common leopard was 69%
(yearly), 76% (colder months) and 60% (warmer months). Thus, habitat separation
should be the result of other factors, most likely avoidance of interspecific
aggression. Habitat separation may not always lead to the use of different prey.
Avoidance of interspecific aggression, rather than exploitation of different
resources, could allow the coexistence of potentially competing large predator
Remote-sensing survey for the assessment of land use diversity - even remote from reality?
Remote-sensing survey for the assessment of land use diversity - even remote from reality?
CIGR E-Journal Volume 5
Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityPeer Reviewed Original Research Articles(29:419 pages): (1) Z. Deng, Y. Sato, and H. Jia. Mapping Land Cover Patterns of Gunma Prefecture, Japan by Using Remote Sensing. Vol. V. January 2003. (2) J.J. Zonderland, H.M. Vermeer, P.F.G. Vereijken, and H.A.M. Spoolder. Measuring a Pig's Preference for Suspended Toys by Using an Automated Recording Technique. Vol. V. February 2003. (3) B. Umar. Comparison of Manual and Manual-cum-Mechanical Energy Uses in Groundnut Production in a Semi-arid Environment. Vol. V. May 2003. (4) A.E. Ghaly, M.S.A. Tango, and M.A. Adams. Enhanced Lactic Acid Production from Cheese Whey with Nutrient Supplement Addition. Vol. V. May 2003. (5) A.E. Ghaly and N.S. Mahmoud. Heat Generated by Mechanical Agitation and Lactose Metabolism during Continuous Propagation of Kluyveromyces fragils in Cheese Whey. Vol. V. May 2003. (6) S. Pedersen, P. Sousa, L. Andersen, and K.H. Jensen. Thermoregulatory Behaviour of Growing-Finishing Pigs in Pens with Access to Outdoor Areas. Vol. V. May 2003. (7) M-J. Cros, F. Garcia, R. Martin-Clouaire, and J-P. Rellier. Modeling Management Operations in Agricultural Production Simulators. Vol. V. May 2003. (8) K. Rosentrater. Performance of an Electrostatic Dust Collection System in Swine Facilities. Vol. V. May 2003. (9) T. Van Pelt. Maize, Soybean, and Alfalfa Biomass Densification. Vol. V. May 2003. (10) T. Satake, O. Sataka, Y. Ohta, and T. Furuya. Optimal Layout Design for Agricultural Facility Using Simulated Annealing. Vol. V. May 2003. (11) Y. Fukumoto, H. Rom, and P. Dahl. Relationship Between Gas Depth Profiles in Compost Heap and Gas Emission. Vol. V. May 2003. (12) C. Ima and D. Mann. Lightbar Design: The Effect of Light Color, Lightbar Size and Auxiliary Indicators on Tracking and Monitoring Performance. Vol. V. June 2003. (13) B.Setiawan, T. Fukuda, and Y. Nakano. Developing Procedures for Optimization of Tank Model?s Parameters. Vol. V. June 2003. (14) K. Takayama, A. Konishi, and K. Omasa. Diagnosis of Invisible Photosynthetic Injury Caused by a Herbicide (Basta) with Chlorophyll Fluorescence Imaging System. Vol. V. June 2003. (15) F. Kumhala, M. Kroulik, and V. Prosek. Dependence of Conditioner Power Input on Mowing Machine Material Feed Rate. Vol. V. July 2003. (16) S. Soekarno and V. Salokhe. Soil Reactions on the Cage Wheels with Staggered Echelons of Half-width Lugs and Perfect Chevron Lugs in Wet Clay Soil. Vol.V. July 2003. (17) A. Campos, L. Pereira, J. Gonclaves, M. Fabiao, Y. Liu, Y. Li, Z. Mao, and B. Dong. Water Saving in the Yellow River Basin, China. 1. Irrigation Demand Scheduling. Manuscript LW 02 007. Vol. V. July 2003. (18) M. Fabiao, J. Gonclaves, L. Pereira, A. Campos, Y. Liu, Y. Li, Z. Mao, and B. Dong. Water Saving in the Yellow River Basin, China. 2. Assessing the Potential for Improving Basin Irrigation. Vol. V. July 2003. (19) S. Lynikiene and A. Pozeliene. Effect of Electrical Field on Barley Seed Germination Stimulation. Vol. V. August 2003. (20) C. Sorensen. Workability and Machinery Sizing for Combine Harvesting. Vol. V. August 2003. (21) C.Sorensen. A Model of Field Machinery Capability and Logistics:the Case of Manure Application. Vol. V. October 2003. (22) A. Tabatabaeefar, H. Aghagoolzadeh, and H. Mobli. Design and Development of an Auxiliary Chickpea Second Sieving and Grading Machine. Vol. V. December 2003. (23) M. Rodrigues, M. Borges, A. Franca, L. Oliveira, and P. Correa. Evaluation of Physical Properties of Coffee during Roasting. Vol. V. December 2003. (24) G. Zhang, A. Ikeguchi, J. Strom, S. Morsing, H. Takai, P. Ravn, and L. Okushima. Obstacle Effects on Airflow and Containment Dispersion around a Naturally Ventilated Livestock Building. Vol. V. December 2003. (25) Z. Tan, Y. Zhang, and S. Ford. Decay of Rotational Airflow with Flow Conditioner in Larger Diameter Ducts for Dust Concentration Measurement using Isokinetic Sampling. Vol. V. December 2003. (26) S. Hillegas nd A. Demirci. Inactivation of Clostridium sporogenes in Clover Honey by Pulsed UV-light Treatment. Vol. V. December 2003. (27) C. Puchalski, G. Brusewitz, and Z. Slipek. Coefficients of Friction for Apple on Various Surfaces as Affected by Velocity. Vol. V. December 2003. (28) A. Elhassan, A. Goto, and M. Mizutani. Effect of Conjunctive Use of Water for Paddy Field Irrigation on Groundwater Budget in an Alluvial Fan. Vol. V. December 2003. (29) S. Mukhtar, A. Rose, S. Capareda, C. Boriack, R. Lacey, B. Shaw, and C. Parnell. Assessment of Ammonia Adsorption onto Teflon and LDPE Tubing used in Pollutant Stream Conveyance. Vol. V. December 2003....Invited Overview Articles(24:320 pages): (1) S. Sokhansanj, J. Cushman, and L. Wright. Collection and Delivery of Feedstock Biomass for Fuel and Power Production. Vol. V. February 2003. (2) M.O. Ngadi, M.I. Bazhal, and G.S.V. Raghavan. Engineering Aspects of Pulsed Electroplasmolysis of Vegetable Tissues. Vol. V. February 2003. (3) J. Zaske. Mechanization and Traceability of Agricultural Production: a Challenge for the Future System Integration and Certification. The Market Demand for Clarity and Transparency-Part 1. Club of Bologna. Nov 16, 2002. Vol. V. February 2003. (4) L. Bodria. System Integration and Certification. The Market Demand for Clarity and Transparency-Part 2. Club of Bologna. Nov. 16, 2002. Vol. V. February 2003. (5) A. Senzanje. Problems Faced and Advances Made by Agricultural Engineers in Southern and Eastern Africa. Vol. V. March 2003. (6) R. Macmillan with a book review by D. Gee Clough. The Mechanics of Tractor-Implement Performance. Vol. V. May 2003. (7) B. Sims. Draft Animal Power for Soil and Water Conservation in the Bolivian Valleys. Vol. V. June 2003. (8) P. Andrade and B. Jenkins. Identification Of Patterns of Farm Equipment Utilization in Two Agricultural Regions of Central and Northern Mexico. Vol. V. June 2003. (9) N. Scott. Consortium of U.S. Universities and Institutions in Cooperation with China for Agriculture. Vol. V. July 2003. (10) H. Dhingra, V. Tewari, and S. Singh. Discomfort, Pressure Distribution and Safety in Operator's Seat-A Critical Review. Vol. V. July 2003. (11) R. Sims. Climate Change Solutions from Biomass, Bioenergy and Biomaterials. Vol. V. September 2003. (12) G. Son, E.H. Bourarach, and J. Ashburner. The Issue of Crops Establishment in Burkina Faso Western Area. Vol. V. September 2003. (13) X. Zhou, R. Dong, S. Li, G. Peng, L. Zhang, J. Hou, J. Xiao and B. Zhu. Agricultural Engineering in China. Vol. V. September 2003. (14) G. Singh. Population and Food Production: Prospects and Challenges for Asia. Vol. V. December 2003. (15) F. Lu. Precision Agriculture Development in Taiwan. Vol. V. December 2003. (16) E. Jiang. Agricultural Production and Research in Heilongjiang Province, China. Vol. V. December 2003. (17) I. Lee, C. Kang, J. Yun, J. Jeun, and G. Kim. A Study of Aerodynamics in Agriculture. Vol. V. December 2003. (18) V. Fung and B. Jenkins. Biomass Power Development for the Philippines. Vol. V. December 2003. (19) J. Reid, J. Schueller, and W. Norris. Reducing the Manufacturing and Management Costs of Tractors and Agricultural Equipment. Club of Bologna. Vol. V. December 2003. (20) J. Reid, J. Schueller, and W. Norris. Reducing the Manufacturing and Management Costs of Tractors and Agricultural Equipment. Power Point Slides. Club of Bologna. Vol. V. December 2003. (21) T. Kobayashi. Reducing the Manufacturing and Management Costs of Tractors and Agricultural Equipment. Club of Bologna. Vol. V. December 2003. (22) T. Kobayashi. Reducing the Manufacturing and Management Costs of Tractors and Agricultural Equipment. Power Point Slides. Club of Bologna. Vol. V. December 2003. (23) Y. Sarig. Traceability of Food Products. Club of Bologna. Vol. V. December 2003. (24) G. Pellizzi. Recommendations and Conclusions--2003. Club of Bologna. Vol. V. December 2003