The effectiveness of hair traps for surveying mammals: results of a study in sandstone caves in the Tasmanian southern midlands

2010 ◽  
Vol 32 (1) ◽  
pp. 62 ◽  
Author(s):  
Rachel L. Harris ◽  
Stewart C. Nicol

We compared detection success of hair tubes and funnels with tape and Velcro adhesives as part of a small-scale mammal survey in sand-bottomed caves in the southern midlands of Tasmania. In order to detect small mammals entering traps but not leaving hair samples behind, a new type of funnel design was tested. In total, 19 species were detected throughout the survey period using a combination of hair traps and track and scat analysis. When tracks were observed inside funnel entrances no hairs were found on the adhesive tapes in 71% of cases. Hairs from several species were found in traps although there were no tracks of these species in the caves. These results further emphasise the importance of using multiple techniques when conducting general mammal surveys. Appropriate hair trap design is an important factor to be considered when conducting mammal surveys, as it has the potential to strongly influence survey efficiency and overall results.

2019 ◽  
Vol 8 (5) ◽  
pp. 239 ◽  
Author(s):  
Zhihui Gu ◽  
Yong Zhu ◽  
Yan Zhang ◽  
Wanyu Zhou ◽  
Yu Chen

Station-free bike sharing systems (BSSs) are a new type of public bike system that has been widely deployed in China since 2017. However, rapid growth has vastly outpaced the immediate demand and overwhelmed many cities around the world. This paper proposes a heuristic bike optimization algorithm (HBOA) to determine the optimal supply and distribution of bikes considering the effect of bicycle cycling. In this approach, the different bike trips with separate bikes can be connected in space and time and converted into a continuous trip chain for a single bike. To improve this cycling efficiency, it is important to properly design the bicycle distribution. Taking Shenzhen as an example, we implement the algorithm with OD matrix data from Mobike and Ofo, the two large bike sharing companies which account for 80% of the shared bike market in Shenzhen, over two days. The HBOA results are as follows. 1) Only one-fifth of the bike supply is needed to meet the current usage demand if the bikes are used efficiently, which means a large number of shared bikes in Shenzhen remain in an idle state for long periods. 2) Although the cycling demand is high in many areas, it does not mean that large numbers of bikes are needed because the continuous inflow caused by the cycling effect of bikes will meet most of the demand by itself. 3) The areas with the highest demands for optimal bikes are residential, followed by industrial, public transportation, official and commercial areas, on both working and non-working days. This algorithm can be an objective basis for city related departments to manage station-free BSSs and be applied to design the layout of bikes in small-scale spatial units to help station-free BSSs operate efficiently and minimize the need to relocate the bikes without reducing the level of user satisfaction.


Author(s):  
Maria Luisa Astolfi ◽  
Carmela Protano ◽  
Elisabetta Marconi ◽  
Lorenzo Massimi ◽  
Daniel Piamonti ◽  
...  

Small-scale or artisanal mining, using gold-mercury amalgamation to extract gold from ore, is a significant source of exposure for the workers and nearby populations. Few studies on hair mercury (Hg) have been conducted in Africa despite the fact that Africa has several gold deposits. No studies have been conducted in Eritrea that is one of the emerging gold producing countries in Africa. The aim of the study was to assess the Hg concentration in hair samples (n = 120) of a population living in Asmara, capital of Eritrea, and to evaluate the influence of some factors on the Hg levels in hair. Information on age, height, weight, occupation, smoking and fish consumption of participants were collected via questionnaire. Hair Hg concentration was significantly higher among women compared to men (p < 0.001) and among women preparing spicy products in Medeber market compared to those who did other jobs (p = 0.010). These results highlight the need for routine biomonitoring surveys and for health promotion campaigns devoted to local decision makers and workers.


Author(s):  
Delphine Laboureur ◽  
Jean-Marie Buchlin ◽  
Patrick Rambaud

The most dangerous accident that can occur in LPG storage is the boiling liquid expanding vapor explosion (BLEVE). To better understand the rupture of the reservoir and the blast wave characteristics, small scale BLEVE experiments are performed with cylinders of 95 ml, filled at 86% with propane, laid horizontally and heated from below. A weakening of the reservoirs on the upper part allows better reproducibility of the rupture. High speed visualization, blast overpressure and surface reservoir temperature are measured. Internal pressure measurement shows that the rupture pressure and temperature are well above the critical point. The fluid is then supercritical and there is no distinction anymore between liquid and gas prior rupture. This kind of reservoir rupture is significant of a new type of BLEVE, a supercritical BLEVE. The experiments also show that the fluid behavior during rupture differs with the size of the weakened part and therefore with the rupture pressure. Finally, the measured peak overpressures are compared with literature models.


1978 ◽  
Vol 5 (1) ◽  
pp. 75 ◽  
Author(s):  
GR Friend

In Gippsland, Victoria, in pine plantations and the adjacent native eucalyptus forest, mammal population was estimated by the usual methods and by analysis of ffaeces of predators. Predators were fox (Vulpes vulpes), feral cat (Felis catus), dog and dingo. Prey species found in faeces included 1 monotreme, 18 marsupial and 10 placental mammals, including the predators. Remains of cattle and sheep were found, presumably eaten as carrion. Remains of plants, or of animals other than the groups noted, were not required to be identified for the purpose of the study, nor were prey species attributed to each species of predator.


1953 ◽  
Vol 6 (3) ◽  
pp. 272 ◽  
Author(s):  
BY Mills ◽  
AG Little

A method of constructing an aerial system of high resolution but small area and low cost is described. Its application to the production of narrow pencil beams at metre wavelengths for investigations in radio astronomy is discussed. A small-scale model has been constructed to test the principle.


2010 ◽  
Vol 6 (S271) ◽  
pp. 367-368
Author(s):  
Benjamin M. Byington ◽  
Nicholas H. Brummell ◽  
Steven M. Tobias

AbstractA dynamo is a process by which fluid motions sustain magnetic fields against dissipative effects. Dynamos occur naturally in many astrophysical systems. Theoretically, we have a much more robust understanding of the generation and maintenance of magnetic fields at the scale of the fluid motions or smaller, than that of magnetic fields at scales much larger than the local velocity. Here, via numerical simulations, we examine one example of an “essentially nonlinear” dynamo mechanism that successfully maintains magnetic field at the largest available scale (the system scale) without cascade to the resistive scale. In particular, we examine whether this new type of dynamo at the system scale is still effective in the presence of other smaller-scale dynamics (turbulence).


2015 ◽  
Vol 97 (1) ◽  
pp. 266-273 ◽  
Author(s):  
Clay M. Wilton ◽  
Jeff Beringer ◽  
Emily E. Puckett ◽  
Lori S. Eggert ◽  
Jerrold L. Belant

Abstract Accounting for low and heterogeneous detection probabilities in large mammal capture–recapture sampling designs is a persistent challenge. Our objective was to improve understanding of ecological and biological factors driving detection using multiple data sources from an American black bear ( Ursus americanus ) DNA hair trap study in south-central Missouri. We used Global Positioning System telemetry and remote camera data to examine how a bear’s distance to traps, probability of space use, sex-specific behavior, and temporal sampling frame affect detection probability and number of hair samples collected at hair traps. Regression analysis suggested that bear distance to nearest hair trap was the best predictor of detection probability and indicated that detection probability at encounter was 0.15 and declined to &lt; 0.05 at nearest distances &gt; 330 m from hair traps. From remote camera data, number of hair samples increased with number of visits, but the proportion of hair samples from known visits declined 39% from early June to early August. Bears appeared attracted to lured hair traps from close distances and we recommend a hair trap density of 1 trap/2.6 km 2 with spatial coverage that encompasses potentially large male home ranges. We recommend sampling during the late spring and early summer molting period to increase hair deposition rates.


2015 ◽  
Vol 24 (5) ◽  
pp. 712 ◽  
Author(s):  
Michael J. Lawes ◽  
Brett P. Murphy ◽  
Alaric Fisher ◽  
John C. Z. Woinarski ◽  
Andrew C. Edwards ◽  
...  

Small mammal (<2 kg) numbers have declined dramatically in northern Australia in recent decades. Fire regimes, characterised by frequent, extensive, late-season wildfires, are implicated in this decline. Here, we compare the effect of fire extent, in conjunction with fire frequency, season and spatial heterogeneity (patchiness) of the burnt area, on mammal declines in Kakadu National Park over a recent decadal period. Fire extent – an index incorporating fire size and fire frequency – was the best predictor of mammal declines, and was superior to the proportion of the surrounding area burnt and fire patchiness. Point-based fire frequency, a commonly used index for characterising fire effects, was a weak predictor of declines. Small-scale burns affected small mammals least of all. Crucially, the most important aspects of fire regimes that are associated with declines are spatial ones; extensive fires (at scales larger than the home ranges of small mammals) are the most detrimental, indicating that small mammals may not easily escape the effects of large and less patchy fires. Notwithstanding considerable management effort, the current fire regime in this large conservation reserve is detrimental to the native mammal fauna, and more targeted management is required to reduce fire size.


2016 ◽  
Vol 5 (3) ◽  
pp. 257 ◽  
Author(s):  
Sofia Sofia ◽  
Adi Heru Husodo ◽  
Eko Sugiharto

<p>Gold amalgamation processes using mercury were practiced in small scale gold mining activities in Krueng Sabee, Aceh Province. Seafood (fish, mollusc, shrimp) and human hair samples were collected to assess mercury concentrations.  Acute and chronic toxicity symptoms which arise among the populations were observed as well as personal protective equipment used by gold miners. The range of mercury concentrations varied among fish, shrimp, and molluscs. The highest mercury levels were recorded in fish <em>Puntius latristriga</em> (172.299 ± 10.626 µg/g wet wt.), followed by mollusc, <em>Polymesoda caroliniana </em> (160,032 ± 0,522 µg/g wet wt.), fish <em>R.kanagurta</em> (149 ±2,000 µg/g wet wt.), shrimp <em>Penaeus monodon</em> (116.975 ± 4.807 µg/g wet wt.).  The variation of mercury concentrations in hair samples of 72 respondents were detected from 5.7 µg/g to 88.1 µg/g. The most frequent acute and chronic intoxication symptoms documented were headache, muscle cramps, cough, and aphthous ulcers. Personal protective equipment which has correlation with high mercury levels in gold miners were respirator/mask, gloves, and apparel (p &lt; 0.05). All seafood samples exceeded 0.5 µg Hg/g MoH Food and Drug Administrasion threshold level and hair samples over 10 µg/g as set by WHO tolerance limit.</p>


XCC (X-Section Cast in place Concrete) pile is new type of pile developed on the basis of cast-in-place pile from the conventional circular pile and capable of resisting displacement. In this study, an attempt is made to investigate the performance of XCC Pile under different loading conditions viz., vertical loading, lateral loading and uplift loading. Experimental investigation is carried out on small scale model piles embedded in sand, by changing type of loading and distance between arc to diameter ratio of the pile. The relative density of soil, type of soil and spacing between the piles are kept constant during investigations. Ultimate capacities of piles are compared with those of conventional circular pile with same diameter and length. The results show that XCC pile with arc distance to diameter ratio equal to 0.3 provides higher vertical and lateral capacity to the extent of 45 % and 39 % respectively compared to that of conventional pile. XCC Pile with arc distance to diameter ratio equal to 0.4 provides higher uplift load capacity to the extent 29 % compared to conventional circular pile.


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