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111.
Remote monitoring of nests using digital camera technology 总被引:3,自引:0,他引:3
Mark Bolton Nigel Butcher Fiona Sharpe Danaë Stevens Gareth Fisher 《Journal of Field Ornithology》2007,78(2):213-220
ABSTRACT. Although cameras have been used for many years to collect data at birds' nests, recent advances in digital technology have led to increased storage capacity, faster and easier review of data, and reduced power consumption. The development of sophisticated triggering mechanisms, such as video motion detection, herald a new era of portable, energy-efficient systems that require less frequent maintenance. We used a digital infrared camera system to monitor predation events at the nests of ground-nesting Lapwings ( Vanellus vanellus ; N = 40) and tree-nesting Spotted Flycatchers ( Muscicapa striata ; N = 17). Eight predator species were recorded taking eggs or chicks at Lapwing ( N = 10) and Spotted Flycatcher ( N = 7) nests, including red fox ( Vulpes vulpes ), badger ( Meles meles ), sheep ( Ovis aries ), and Carrion Crow ( Corvus corone ) at Lapwing nests and Eurasian Jay ( Garrulus glandarius ), European Buzzard ( Buteo buteo ), Great-spotted Woodpecker ( Dendrocopus major ), and domestic cat ( Felis catus ) at flycatcher nests. We tested three system configurations in an attempt to minimize power requirements and maximize predation-event recording capability. We found that the use of a passive-infrared sensor to awaken the system from standby mode did not compromise reliability and reduced power consumption. With this system, a 38-A h battery operated the system for 120 h with no maintenance at a cost per unit of about $800 (US; or £400 UK Sterling). Further modifications would permit adaptation of the system for a wide range of scientific and nest surveillance operations. 相似文献
112.
近年来随着民用无人机的普及,无人机开始越来越多地应用于风景园林领域中。但目前大多数应用还停留在基础的航拍层面,对于应用潜力更大的航测层面,在风景园林行业中的应用相对较少,也更鲜为人知,现有研究更多聚焦于具体案例的应用方面,未能对其进行系统的认知和介绍。简要介绍无人机航测与遥感系统的构成及常见传感器类型,通过文献综合、项目实践等方法,系统地整理了国内外无人机航测相关的研究与应用进展,进而总结出无人机航测在风景园林中的应用可分为传统航测、倾斜摄影、多种传感器遥感3个方面。最后指出传统航测发展最为成熟,短时间内推广应用的可能性最大;倾斜摄影效率最高;多种传感器遥感未来开发潜力最大。以期对今后无人机在风景园林中的应用与研究有所启发。 相似文献
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115.
Chaoying S. Xu Jessica S. Chen Ron A. Adelman 《The Yale journal of biology and medicine》2015,88(3):309-317
Video games have surged in popularity due to their entertainment factor and, with recent innovation, their use in health care. This review explores the dual facets of video games in treating vision impairment in amblyopia as well as their potential for overuse and addiction. Specifically, this review examines video game addiction from a biopsychosocial perspective and relates the addictive qualities of video games with their use as a therapeutic treatment for amblyopia. Current literature supports both the identification of video game addiction as a disease, as well as the therapeutic potential of video games in clinical trials. We show the need for clinicians to be aware of the dangers associated with video game overuse and the need for future studies to examine the risks associated with their health care benefits. 相似文献
116.
This study provides the first assessment of fish associations with oil and gas structures located in deep water (85–175 m) on Australia's north‐west continental shelf, using rare oil industry video footage obtained from remotely operated vehicles. A diverse range of taxa were observed associating with the structures, including reef‐dependent species and transient pelagic species. Ten commercially fished species were observed, the most abundant of which was Lutjanus argentimaculatus, with an estimated biomass for the two deepest structures (Goodwyn and Echo) of 109 kg. 相似文献
117.
Nocturnal predators are often overlooked in biological control studies, despite evidence that they can make important contributions to insect pest suppression in agroecosystems. Many sampling methods are only employed during the daytime hours due to limitations of time and labour. Additionally, different sampling methods can provide contrasting information about natural enemy community composition and relative abundance. Here, we use Aphis glycines and its arthropod predators as a model system to compare natural enemy community composition described by vacuum samples, direct observations and video observations across the diel cycle in soybean. All sampling methods identified several common taxa. Anthocorids were dominant in vacuum samples and direct observations, and both methods indicated that this taxa may be more active in the afternoon. In contrast, anthocorids were recorded infrequently on video, possibly due to their small size. On video samples, lacewing larvae were the most active taxa during the day and lacewing larvae, spiders, opiliones and carabids were the most active taxa at night. We directly observed 22 predation events on soybean aphid: 17 by anthocorids, two by chrysopid larvae, and one each by a coccinellid, spider and predatory mite. The differences between the sample methods suggest that vacuum samples may represent predator abundance more accurately, while video data may miss small predators, but can be used to better assess relative time spent foraging. 相似文献
118.
Mami Nomura Takuro Nakayama Ken‐ichiro Ishida 《The Journal of eukaryotic microbiology》2014,61(3):317-321
Most euglyphids, a group of testate amoebae, have a shell that is constructed from numerous siliceous scales. The euglyphid Paulinella chromatophora has photosynthetic organelles (termed cyanelles or chromatophores), allowing it to be cultivated more easily than other euglyphids. Like other euglyphids, P. chromatophora has a siliceous shell made of brick‐like scales. These scales are varied in size and shape. How a P. chromatophora cell makes this shell is still a mystery. We examined shell construction process in P. chromatophora in detail using time‐lapse video microscopy. The new shell was constructed by a specialized pseudopodium that laid out each scale into correct position, one scale at a time. The present study inferred that the sequence of scale production and secretion was well controlled. 相似文献
119.
We present two methods for observing bumblebee choice behavior in an enclosed testing space. The first method consists of Radio Frequency Identification (RFID) readers built into artificial flowers that display various visual cues, and RFID tags (i.e., passive transponders) glued to the thorax of bumblebee workers. The novelty in our implementation is that RFID readers are built directly into artificial flowers that are capable of displaying several distinct visual properties such as color, pattern type, spatial frequency (i.e., “busyness” of the pattern), and symmetry (spatial frequency and symmetry were not manipulated in this experiment). Additionally, these visual displays in conjunction with the automated systems are capable of recording unrewarded and untrained choice behavior. The second method consists of recording choice behavior at artificial flowers using motion-sensitive high-definition camcorders. Bumblebees have number tags glued to their thoraces for unique identification. The advantage in this implementation over RFID is that in addition to observing landing behavior, alternate measures of preference such as hovering and antennation may also be observed. Both automation methods increase experimental control, and internal validity by allowing larger scale studies that take into account individual differences. External validity is also improved because bees can freely enter and exit the testing environment without constraints such as the availability of a research assistant on-site. Compared to human observation in real time, the automated methods are more cost-effective and possibly less error-prone. 相似文献
120.