Camera Sites Research Articles

利用红外照相技术分析野生白冠长尾雉活动节律及时间分配

The researches on activity rhythm and behavioral time budgets of vulnerable or endangered species were of great importance to form the effective conservation strategies,Reeves' s Pheasant(Syrmaticus reevesii) was a vulnerable species endemic to China,whereas little information on activity rhythm and behavioral time budgets of this species was available.Therefore,we used infrared camera technology,from March 2012 to March 2013,to survey the activity rhythm and behavioral time budgets of wild Reeves' s Pheasant(Syrmaticus reevesii) in Caihe Town,Guangshui City,Hubei province.We radio tracked and outlined 8 Reeves' s Pheasants in the study area at first,and then we determined 4—5 sites as candidate camera sites in each home range. We selected two camera sites with a distance apart from at least 200 m in a home range synchronously,and irregularly moved these cameras across the candidate camera sites in this home range. In consequence,we set 16 infrared cameras at 40 candidate camera sites. The daily work time of a camera was set from 4: 00 to22: 00 with the reference to some previous reports on this pheasant behavior,and we defined it as a camera day. We also divided the behavior of wild Reeves' s Pheasant into seven types,including feeding,moving,grooming,vigilance,resting,conflicting,and raising According to the available information on pheasant behavior. As a result,the total work time of these cameras in the field added up to 1774 d. We obtained totally 2242 videos in relation to Reeves' s Pheasants that were responsible for about 18% with a total of 538 individuals in relation to 396 behavior samples. The sex ratio between the female and male photoed is 1.43∶1. Two diurnal activity peaks were observed for the wild individuals,and the activity peak in the morning was around 9: 00 and that in the afternoon was around 17: 00. In particular,the activity peak of the males in the morning was much earlier about two hours than that of females,i.e. 7: 00—9: 00 for the males and 9: 00—11: 00 for the females. The behavior of moving and feeding dominated the diurnal behaviors of Reeves' s Pheasant,accounting for 40. 71%and 33.10%,respectively,and then followed in order by vigilance(9. 29%),grooming(7. 14%),resting(5. 00%),conflicting(2. 62%),raising(2. 14%). The frequency of vigilance of females was significantly higher than that of the males. The wild Reeves' s Pheasant also showed significant seasonal behavior variations,and the rate of feeding,moving,and conflicting varied among seasons. For example,the feeding frequency in winter was much higher than that in summer(P0.05),and the moving frequency in summer was higher than that in autumn(P0.05) and winter(P0. 05),whereas the frequency of conflicting,grooming,resting,and raising did not differ significantly. Given this study was conducted in an area with higher human disturbance,it was reasonable to recommend these results to that happened in an area with less human disturbance(e.g. nature reserves) in the future. The practice of this study also proved that infrared camera technology is very suitable for studying highly alert and rare terrestrial forest birds.

Assessing sloth bears as surrogates for carnivore conservation in Sri Lanka

Bears are large, charismatic mammals whose presence often garners conservation attention. Because healthy bear populations typically require large, contiguous areas of habitat, land conservation actions often are assumed to benefit co-occurring species, including other mammalian carnivores. However, we are not aware of an empirical test of this assumption. We used remote camera data from 2 national parks in Sri Lanka to test the hypothesis that the frequency of detection of sloth bears (Melursus ursinus) is associated with greater richness of carnivore species. We focused on mammalian carnivores because they play a pivotal role in the stability of ecological communities and are among Sri Lanka's most endangered species. Seven of Sri Lanka's carnivores are listed as endangered, vulnerable, or near threatened, and little empirical information exists on their status and distribution. During 2002–03, we placed camera traps at 152 sites to document carnivore species presence. We used Poisson regression to develop predictive models for 3 categories of dependent variables: species richness of (1) all carnivores, (2) carnivores considered at risk, and (3) carnivores of least conservation concern. For each category, we analyzed 8 a priori models based on combinations of sloth bear detections, sample year, and study area and used Akaike's information criterion (AICc) to test our research hypothesis. We detected sloth bears at 55 camera sites and detected 13 of Sri Lanka's 14 Carnivora species. Species richness of all carnivores showed positive associations with the number of sloth bear detections, regardless of study area. Sloth bear detections were also positively associated with species richness of carnivores at risk across both study years and study areas, but not with species richness of common carnivores. Sloth bears may serve as a valuable surrogate species whose habitat protection would contribute to conservation of other carnivores in Sri Lanka.

The impact of forest logging and fragmentation on carnivore species composition, density and occupancy in Madagascar's rainforests

AbstractForest carnivores are threatened globally by logging and forest fragmentation yet we know relatively little about how such change affects predator populations. This is especially true in Madagascar, where carnivores have not been extensively studied. To understand better the effects of logging and fragmentation on Malagasy carnivores we evaluated species composition, density of fossaCryptoprocta feroxand Malagasy civetFossa fossana, and carnivore occupancy in central-eastern Madagascar. We photographically-sampled carnivores in two contiguous (primary and selectively-logged) and two fragmented rainforests (fragments <2.5 and >15 km from intact forest). Species composition varied, with more native carnivores in the contiguous than fragmented rainforests.F. fossanawas absent from fragmented rainforests and at a lower density in selectively-logged than in primary rainforest (mean 1.38±SE 0.22 and 3.19±SE 0.55 individuals km−2, respectively).C. feroxwas detected in fragments <2.5 km from forest and had similar densities in primary and selectively-logged forests (0.12±SE 0.05 and 0.09±SE 0.04 adults km−2, respectively) but was absent in fragments >15 km from forest. We identified only two protected areas in Madagascar that may maintain >300 adultC. ferox. Occupancy of broad-striped mongooseGalidictis fasciatawas positively related to fragment size whereas occupancy of ring-tailed mongooseGalidia elegans eleganswas negatively associated with increasing exotic wild cat (Felisspp.) activity at a camera site. Degraded rainforest fragments are difficult environments for Malagasy carnivores to occupy; there is a need to prioritize the reconnection and maintenance of contiguous forest tracts.

Adaptive frame synchronization for surveillance system across a heterogeneous network

As mobile techniques are booming, the surveillance function is extended from a stationary mode to a mobile mode. In a heterogeneous network environment, cameras and viewers are located in different networks so that frame synchronization may span across diverse network domains with different transmission capabilities. The mismatch of transmission capabilities may affect the viewing continuity and playback liveness between cameras and viewers. In the article, we propose an adaptive frame synchronization mechanism for frame capturing at cameras based on the network condition to improve the frame synchronization between two sides across a heterogeneous network. Based on a brief theoretical analysis of the asynchronization effect for video communication in a heterogeneous network environment, the proposed adaptive pause time mechanism can be an effective solution to relieve the asynchronization effect in the unmatched transmission rate situation. The evaluation results show that the proposed scheme can achieve a shorter time delay between the captured frames at the camera site and the viewer site.

Estimating sika deer abundance using camera surveys

Cameras have been used throughout the world to estimate wildlife abundance and occupancy. Abundance estimates generated by camera surveys tend to be less invasive, less costly, and more accurate than other means in certain situations. We sought to expand and test the effectiveness of camera surveys on sika deer in Maryland. In 2008, we setup surveys with a 7-day pre-bait period followed by a 7-day active camera survey with 15 cameras. In 2009, we ran the cameras for the entire 14-day survey and moved cameras after each survey to determine if biases occur when using the same camera sites. During both years and all surveys, camera density was approximately 1-camera/65-ha. The abundance estimates were similar between years and estimators. In 2009, increasing photo intervals from 1-min to 5- and 10-min intervals reduced the number of pictures by 66 and 81%, respectively, while providing similar abundance estimates. We calculated the daily detection probabilities for all identifiable deer and we used radio-collared males that occurred within 2 km of the survey grid to assist in determining the optimum survey length. Detection probability did not vary between surveys in the same year, but varied between 2008 and 2009, most likely due to unlimited bait being available during 2008 surveys. Camera surveys have proven to be an accurate and cost effective means of estimating wildlife abundance and can be used successfully to determine sika deer abundance.

Linking road casualty and clinical data to assess the effectiveness of mobile safety enforcement cameras: a before and after study

ObjectivesTo use police STATS19 road casualty data and accident and emergency and in-patient information to estimate the impact of mobile safety cameras on the cost of treating individuals injured in...

Safety cameras and road accidents: effectiveness in local authority areas in England

Safety cameras have been central to strategy for improving road safety in the UK (and other countries) over the past decade and a National Safety Camera (NSC) programme was introduced in the year 2000 to fund and guide the expansion of camera sites. This programme was brought to an end in 2007 and responsibility for decisions on expanding, maintaining or rolling back safety cameras has now been largely devolved to local highway authorities and their partners. To make strategic choices in such areas it is clearly vital to understand the extent to which safety cameras are effective in reducing road accident potential. Although the NSC programme has been evaluated this work has focussed mainly on assessments of impacts at camera sites rather than wider area effects: particularly local highway area effects. The research reported here has explored the rates of personal injury collisions (PIC) over the past decade on the roads of English Local Authority areas and investigated relationships between area characteristics including levels of safety camera introductions and the PIC improvements (or otherwise) reported. To assist in this analysis, an indicator of safety camera intensity has been derived in this research to reflect the relative likelihood in areas of coming into contact with safety camera sites This work shows that area improvement rates differ significantly on an urban/rural dimension and are also very dependent on prior (to camera introductions) levels of PIC risk. Controlling for these factors using a pair comparison approach, analysis shows that safety camera introduction effects are statistically detectable in very highly urbanised, high PIC risk areas and at high risk sites within areas but not elsewhere. Whilst recognising that new high risk sites can emerge in any area, the conclusion is reached that many local areas and especially more rural areas would be unlikely to gain advantage from a further general expansion of fixed point and mobile camera sites and that de-commissioning of current sites should be seriously considered.

Efficiency of time‐lapse intervals and simple baits for camera surveys of wild pigs

AbstractGrowing concerns surrounding established and expanding populations of wild pigs (Sus scrofa) have created the need for rapid and accurate surveys of these populations. We conducted surveys of a portion of the wild pig population on Fort Benning, Georgia, to determine if a longer time‐lapse interval than had been previously used in surveys of wild pigs would generate similar detection results. We concurrently examined whether use of soured corn at camera sites affected the time necessary for pigs to locate a new camera site or the time pigs remained at a site. Our results suggest that a 9‐min time‐lapse interval generated dependable detection results for pigs and that soured corn neither attracted pigs to a site any quicker than plain, dry, whole‐kernel corn, nor held them at a site longer. Maximization of time‐lapse interval should decrease data and processing loads, and use of a simple, available bait should decrease cost and effort associated with more complicated baits; combination of these concepts should increase efficiency of wild pig surveys. © 2011 The Wildlife Society.

Human Activity Helps Prey Win the Predator-Prey Space Race

Predator-prey interactions, including between large mammalian wildlife species, can be represented as a “space race”, where prey try to minimize and predators maximize spatial overlap. Human activity can also influence the distribution of wildlife species. In particular, high-human disturbance can displace large carnivore predators, a trait-mediated direct effect. Predator displacement by humans could then indirectly benefit prey species by reducing predation risk, a trait-mediated indirect effect of humans that spatially decouples predators from prey. The purpose of this research was to test the hypothesis that high-human activity was displacing predators and thus indirectly creating spatial refuge for prey species, helping prey win the “space race”. We measured the occurrence of eleven large mammal species (including humans and cattle) at 43 camera traps deployed on roads and trails in southwest Alberta, Canada. We tested species co-occurrence at camera sites using hierarchical cluster and nonmetric multidimensional scaling (NMS) analyses; and tested whether human activity, food and/or habitat influenced predator and prey species counts at camera sites using regression tree analysis. Cluster and NMS analysis indicated that at camera sites humans co-occurred with prey species more than predator species and predator species had relatively low co-occurrence with prey species. Regression tree analysis indicated that prey species were three times more abundant on roads and trails with >32 humans/day. However, predators were less abundant on roads and trails that exceeded 18 humans/day. Our results support the hypothesis that high-human activity displaced predators but not prey species, creating spatial refuge from predation. High-human activity on roads and trails (i.e., >18 humans/day) has the potential to interfere with predator-prey interactions via trait-mediated direct and indirect effects. We urge scientist and managers to carefully consider and quantify the trait-mediated indirect effects of humans, in addition to direct effects, when assessing human impacts on wildlife and ecosystems.

Bias associated with baited camera sites for assessing population characteristics of deer

AbstractCamera surveys often involve placing bait in front of the camera to capture animals more frequently, which could introduce biases in parameter estimates. From September 2008 to March 2009, we monitored cameras placed at random, along game trails, and at feed stations to determine if camera placement influenced measures of population demographics in a herd of white‐tailed deer (Odocoileus virginianus). There was no time period in which cameras placed at feed stations provided sex ratio and recruitment estimates similar to those acquired from randomly placed cameras. Trail‐based camera surveys provided population estimates similar to those from random sites and may provide a feasible alternative to using baited camera stations. © 2011 The Wildlife Society.

A Fatal Motorcycle Accident, UK Road Traffic Legislation Since 1903 and Recent Changes in the Law

The risks of traveling by motorcycle are well recognized, both in terms of excess speed and relative lack of physical protection. Legislation since 1903 has been on-going to try to reduce the carnage on the roads and to recognize the financial problems that such a death leaves behind for the families of the victim. An overview of speed cameras currently in use is given with the more frequent use of ANPR (automatic number plate recognition) cameras for surveillance of known and suspected criminals, valid car insurance verification, current Ministry of Transport mechanical certificates and, increasingly, for with average speed calculation between camera sites. The latter resulting in the surprising and unexpected penalty notice in the post often many days after the incident, though to be legal in England and Wales, it must be served with 14 days of the infraction. Discussed in this case, and of considerable interest, is the hypothesis that a full-face helmet for a motorcyclist may be potentially more dangerous in a crash, due the increased weight, inertia and pendulum effect result in an increased risk of fatal basal skull ring fractures.

Florida Panther Flehmen Response Recorded at Baited Trail Camera Site

Although flehmen behavior is reported in felids, this display has been rarely documented in wild pumas. On 11 Nov. 2008, we recorded a female Puma concolor coryi (Florida Panther) exhibiting the flehmen response and scent marking in reaction to a baited trail camera site in Everglades National Park. The addition of scent lures to our camera sites increased the number of exposures per panther visit, enhancing the possibility of gender identification, an essential component of our annual survey.

Estimating Brown Hyaena Occupancy Using Baited Camera Traps

Conservation and management of brown hyaenas (Hyaena brunnea) is hampered by a lack of information on abundance and distribution, which is difficult and labour-intensive to obtain. However, occupancy surveys offer a potentially efficient and robust means of assessing brown hyaena populations. We evaluate the efficacy of camera trapping for estimating brown hyaena occupancy, and the effect of environmental variables and lures on detection probability. We estimated population density in Pilanesberg National Park, South Africa, at 2.8/100 km2, occupancy at 1.0 and model-averaged detection probability at 0.1. Using a fish lure increased detection probability to 0.2 and significantly increased encounter rates. We also found that brown hyaenas are more likely to be detected in areas of scrub or woodland rather than grassland. Our results suggest that 13 camera sites would be needed to achieve an occupancy estimate with S.E. of 0.05, and a minimum of 16–34 sampling occasions (with and without the fish lure) should be used in comparable study areas. We conclude that camera trapping is a viable method of estimating brown hyaena occupancy at local and landscape scales and capture—recapture analysis is also possible at a local scale.

The effects of mobile speed camera introduction on road traffic crashes and casualties in a rural county of England

ProblemThis study assesses the impact of crash and casualty numbers in correspondence to the introduction of mobile speed cameras in the rural county of Norfolk, England. MethodRoad traffic accident casualty and crash data were collected for two years before the introduction of cameras and two years subsequently. The casualties and crashes occurring at 29 camera sites were identified and separated from those occurring in the rest of the county. Trends in crashes and casualties, and their severity, were examined graphically and comparisons were made between before and after periods. The regression to the mean effect at individual sites was estimated. ResultsAfter the introduction of cameras, overall crashes declined by 1% and crashes involving fatalities or serious injuries declined by 9% on the roads without cameras. At the camera sites, crashes decreased by 19% and fatal and serious crashes by 44%. The reduction in total crashes was significantly greater than that expected from the effect of regression to the mean in 12 out of 20 sites tested. SummaryThe introduction of cameras appears to have resulted in real and measurable reductions in crash risk in this rural county. Impact on industryOur results suggest the deployment of mobile speed cameras is an effective tool for organizations wishing to reduce road traffic casualties in areas where high crash rates have been associated with excessive vehicle speeds.

Activity patterns, behavioural repertoires, and agonistic interactions of crayfish: A non-manipulative field study

AbstractAgonistic behaviour of crayfish has been studied extensively in laboratory settings where pairs or groups of individuals are allowed to interact within an experimental arena. Crayfish agonistic behaviour within its natural context, however, has received little attention to date. The present, non-manipulative field study explored activity patterns, behavioural repertoires, and agonistic encounters of rusty crayfish (Orconectes rusticus) during the summer months using continuous, 24-hour, underwater video recording at a series of representative field sites. Following the filming, crayfish within the vicinity of the camera site were captured and measured. Individual densities were high, reaching a maximum of 68 individuals/m2 at some sites. Large crayfish predominantly inhabited deeper sections of the river and were mostly active at night, whereas small crayfish generally utilized the shallows and were active outside their burrows during day and dusk. Time outside their shelter was mainly used for feeding. Individuals frequently returned to the same shelter they had emerged from. Agonistic encounters were common events and generally occurred in the context of shelter acquisition or defense. Dyadic fighting progressed with escalating sequences of stereotyped aggressive acts. Furthermore, high intensities with unrestrained use of claws were seen in encounters between size-matched opponents. The results of this study allow us to root laboratory findings of crayfish aggression within a comprehensive, ethological framework and to consider ultimate consequences for individual fighting decisions and strategies.

The deterrent effect of increasing fixed penalties for traffic offences: The Norwegian experience

Problem Many motorized countries use fixed penalties to deter the most common traffic violations. Fixed penalties are usually given at the spot by a police officer. If the offender accepts the fixed penalty, no court hearing or trial is held. During the years 1995–2004, the rates for fixed penalties for traffic offences in Norway increased substantially. This paper evaluates the effects on compliance of these increases. Method Regression analysis was performed to determine the effects of increases in fixed penalties. Results For speeding in general, no effect of increasing fixed penalties can be found. For speeding close to speed camera sites, there is a weak tendency for the violation rate to go down. This tendency is not statistically significant at conventional levels. For seat belt wearing, wearing rates are found to increase as fixed penalties have increased. In recent years, however, enforcement of the seat belt law has stepped up, making it impossible to separate the effect of enforcement from that of fixed penalties. Impact on industry It has been suggested that the police may adapt to stricter penalties by reducing enforcement or by adopting larger tolerance margins for violations. Available evidence does not support this hypothesis.

Recreation and large mammal activity in an urban nature reserve

Human recreation has immediate and long-term impacts on wildlife, and exposure to recreational activities might be particularly high in urban systems. We investigated the relationship between human recreation and the spatial and temporal activity patterns of large mammals in an urban nature reserve. Data from remotely triggered infra-red cameras (1999–2001) were used to assess activity for bobcat, coyote, mule deer, humans, and domestic dogs along paths in the Nature Reserve of Orange County (NROC), California. Forty-nine camera sites established across the NROC yielded 16,722 images of humans, dogs, and our three target large mammal species during 4232 observation nights. Results suggest that bobcats, and to a lesser degree coyotes, exhibited both spatial and temporal displacement in response to human recreation. Bobcats were not only detected less frequently along trails with higher human activity, but also appeared to shift their daily activity patterns to become more nocturnal in high human use areas; negative associations between bobcat and human activity were particularly evident for bikers, hikers, and domestic dogs. In general, both bobcats and coyotes displayed a relatively wide range of activity levels at sites with low human use, but a lower and markedly restricted range of activity at those sites with the highest levels of recreation. Although we did not find a clear and consistent pattern of avoidance of human recreation by deer, the probability of detecting deer during the day was lower with increasing levels of human recreation. Future studies that experimentally investigate the impacts of recreationists on wildlife, as well as relate behavioral responses to survival and reproduction, will allow further insight of the effects of urban recreation on large mammal populations.

Overtaking Rule Method for the Cleaning of Matched License-Plate Data

In recent years automatic number plate recognition systems have been increasingly used to monitor urban link travel time. However, the set of travel times produced will contain erroneous records for a variety of reasons including the misreading of the licence plates by the camera, vehicles stopping en-route, and vehicles taking nondirect routes between the two camera sites. This paper proposes a novel technique called the overtaking rule, which uses the serial temporal structure of the data to filter out these erroneous travel time records. The paper proposes a methodology to measure the performance of a licence plate cleaning method, and it is subsequently shown that the overtaking rule outperforms existing cleaning methods.

Characterizing red light runners following implementation of a photo enforcement program

Red light running causes about 260,000 crashes and 750 fatalities each year in the US (Retting, Ulmer, & Williams, 1999, Accident Analysis & Prevention). This study investigated the effects of photo enforcement cameras on reducing red light running and characterized the typical red light runner throughout photo enforcement program implementation. In Southeast Virginia, eight intersections were observed over an 8-month period during which photo enforcement cameras were installed at three sites. To assess spillover effects, three other sites served in a same city comparison group. Two additional sites from a nearby city served in a control group for city. Over 1750 light cycles were observed with red light running occurring at least once during 13% of these cycles. Predictors of red light runners included being at a site without a camera or at an intersection before deployment of cameras, being under the age of 26, being in the non-camera city, not using a safety belt, and driving in more traffic. While overall red light running decreased at camera sites, characteristics of the typical red light runner remained the same at camera and non-camera locations.

Effectiveness of speed cameras in preventing road traffic collisions and related casualties: systematic review

Objectives To assess whether speed cameras reduce road traffic collisions and related casualties.Design Systematic review.Data sources Cochrane Injuries Group Specialised Register, Cochrane Central Register of Controlled Trials, Medline, Embase, Social...