Comparative temperature in funnel and pit traps

2009 ◽  
Vol 57 (5) ◽  
pp. 311 ◽  
Author(s):  
Graham G. Thompson ◽  
Scott A. Thompson

The temperature in pit and funnel traps with various shade-cover treatments on the two hottest days in Perth in the summer of 2008/09 were examined. Lethal temperatures for small mammals and reptiles were experienced in pipe and bucket pit-traps and funnel traps without covers on both days. Funnel traps with shade covers provided similar or better protection from solar radiation than buckets, pipes and funnel traps without covers. A breeze reduced temperatures in funnel traps more than it did in bucket and pipe pit-traps. It is recommended that all funnel traps deployed during fauna surveys be protected by a shade cover and during hot conditions a second shade cover should be used.

1999 ◽  
Vol 26 (3) ◽  
pp. 341 ◽  
Author(s):  
Trevor J. Hobbs ◽  
Craig D. James

Shade covers for pitfall traps can be used to reduce the amount of solar radiation penetrating to the bottom of pitfall buckets, thereby reducing the number of captured animals dying from heat-stress. We tested the effectiveness of a variety of shade covers for reducing temperatures in pitfalls and trap mortality of small vertebrates, and examined the effect of one cover design on trap success in arid landscapes. Shade covers made of insulation foil were found to reduce core pitfall temperatures by 20–22˚C compared with uncovered buckets, which reached temperatures greater than 66ºC. Other cover types tested (plastic lid or cardboard) were found to be less effective: core bucket temperatures still reached 48–53ºC. While foil covers do reduce temperatures and therefore the probability of heat-stress-related mortality, above-ground foil covers also influence trap success. Traps with above-ground foil covers caught 39–43% fewer small vertebrates and 7–42% fewer species than uncovered traps. Above-ground foil covers had the greatest influence on the sampled abundance of scincid lizards (reduced by 50–52%), reduced the sampled abundance of most other lizard families and mammals, but increased capture success for snakes. If shade covers are required to minimise heat stress and mortality in pitfall buckets we recommend foil covers placed inside the bottom pitfall buckets as they significantly reduce pitfall temperatures and are likely to have minimal influence on trap success. However, regular checking of traps is still one of the most reliable ways to reduce heat-stress- related and other deaths in pitfall traps.


1968 ◽  
Vol 16 (5) ◽  
pp. 725 ◽  
Author(s):  
MD Murray

Many D. ovis are found more than 1/4 in. from the skin of the sheep, and 30-50% of a louse population may be lost when the sheep is shorn. The lice near the tip of the fleece come to the tip quickly when it is shaded and warmed, particularly when the fleece is short, and consequently lice, mainly adults and stage III nymphs, spread rapidly from sheep to sheep which are in close contact. All nymphal and adult stages of D. ovis were killed when exposed to 48�C for 60 min, 50�C for 30 min, or to 55 or 60�C for 5 min. Some lice died when exposed to 45�C for 4 hr but the main effect was on oviposition, and females exposed for only 2 hr laid fewer eggs. Most eggs were killed when exposed to 45�C for 4 hr, 47�C for 2-4 hr, or 49�C for 4-1 hr. The intensity of solar radiation during the summer in Australia can result in a temperature gradient within the fleece of sheep from c. 45�C near to the skin to 65-70�C at the tip of the fleece within 5-10 min of exposure. Many lice in the distal parts of the fleece are killed as lethal temperatures develop, and the number of eggs laid by survivors may be reduced. On newly shorn sheep even lice and eggs near the skin may be killed, as the temperature near the skin can rise to 45-52�C. Reasonably heavy infestations may be maintained on sheep kept permanently in the shade, and it appears that the cumulative effect of repeated mortalities due to solar radiation prevents an increase in numbers of D. ovis during the summer.


Space Weather ◽  
2006 ◽  
Vol 4 (6) ◽  
pp. n/a-n/a ◽  
Author(s):  
Tracy Staedter
Keyword(s):  

2003 ◽  
Vol 107 ◽  
pp. 743-747
Author(s):  
D. R.S. Lean ◽  
SD. Siciliano
Keyword(s):  

2019 ◽  
pp. 53-65
Author(s):  
Renata Domingos ◽  
Emeli Guarda ◽  
Elaise Gabriel ◽  
João Sanches

In the last decades, many studies have shown ample evidence that the existence of trees and vegetation around buildings can contribute to reduce the demand for energy by cooling and heating. The use of green areas in the urban environment as an effective strategy in reducing the cooling load of buildings has attracted much attention, though there is a lack of quantitative actions to apply the general idea to a specific building or location. Due to the large-scale construction of high buildings, large amounts of solar radiation are reflected and stored in the canyons of the streets. This causes higher air temperature and surface temperature in city areas compared to the rural environment and, consequently, deteriorates the urban heat island effect. The constant high temperatures lead to more air conditioning demand time, which results in a significant increase in building energy consumption. In general, the shade of the trees reduces the building energy demand for air conditioning, reducing solar radiation on the walls and roofs. The increase of urban green spaces has been extensively accepted as effective in mitigating the effects of heat island and reducing energy use in buildings. However, by influencing temperatures, especially extreme, it is likely that trees also affect human health, an important economic variable of interest. Since human behavior has a major influence on maintaining environmental quality, today's urban problems such as air and water pollution, floods, excessive noise, cause serious damage to the physical and mental health of the population. By minimizing these problems, vegetation (especially trees) is generally known to provide a range of ecosystem services such as rainwater reduction, air pollution mitigation, noise reduction, etc. This study focuses on the functions of temperature regulation, improvement of external thermal comfort and cooling energy reduction, so it aims to evaluate the influence of trees on the energy consumption of a house in the mid-western Brazil, located at latitude 15 ° S, in the center of South America. The methodology adopted was computer simulation, analyzing two scenarios that deal with issues such as the influence of vegetation and tree shade on the energy consumption of a building. In this way, the methodological procedures were divided into three stages: climatic contextualization of the study region; definition of a basic dwelling, of the thermophysical properties; computational simulation for quantification of energy consumption for the four facade orientations. The results show that the façades orientated to north, east and south, without the insertion of arboreal shading, obtained higher values of annual energy consumption. With the adoption of shading, the facades obtained a consumption reduction of around 7,4%. It is concluded that shading vegetation can bring significant climatic contribution to the interior of built environments and, consequently, reduction in energy consumption, promoting improvements in the thermal comfort conditions of users.


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