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1.
ABSTRACT. A variety of photographic methods have been described for monitoring nest predation. All have limitations for studying active nests in remote situations, such as size, expense, volume of data recorded, and types of trigger mechanisms. We developed a digital video surveillance system using infrared cameras to monitor predation at bird nests. The main advantage of this system over other video recorders is the small size of the recorder that can run continuously at 29 frames/s for more than 3 days. The recorder's built-in monitor makes it more transportable and allows for easy setup. Digital data is compact, can be reviewed quickly, and requires less physical storage space than videotapes. We recorded nest predation by mammals, birds, and snakes as well as egg and nestling losses not caused by predation. System failure rates were low and the total cost was comparable to ($700 US) video cassette recorders that are often used to monitor nests. 相似文献
2.
ABSTRACT. Inspection of cavity nests and nest boxes is often required during studies of cavity-nesting birds, and fiberscopes and pole-mounted video cameras are sometimes used for such inspection. However, the cost of these systems may be prohibitive for some potential users. We describe a user-built, wireless cavity viewer that can be used to access cavities as high as 15 m and with entrance diameters as small as 2.5 cm. System components include a wireless camera, boom with near-infrared lighting system, hand-held television, and telescoping pole. The unit can be assembled in about one day with commonly available tools, and the total cost was about $850 (US). Our cavity-viewing system was used to monitor the nests of Western Bluebirds ( Sialia mexicana ) and proved to be reliable and effective. During two field seasons, we attempted to check the status of nests 928 times and were able to determine the nesting stage 901 times (97%). For those willing to assemble their own units, our cavity viewer permits safe, direct examination of cavity nests or open nests for investigators with limited budgets. 相似文献
3.
Alicia K. Andes Terry L. Shaffer Mark H. Sherfy Chantel M. Hofer Colin M. Dovichin Susan N. Ellis‐Felege 《Ibis》2019,161(2):286-300
For federally listed species such as Least Tern Sternula antillarum and Piping Plover Charadrius melodus, correct determination of nest fates and causes of nest failure is crucial for understanding population dynamics and improving monitoring programmes. We used video cameras to evaluate nest fate misclassification rate and to identify factors that may cause researchers monitoring nests at different intervals to classify Least Tern and Piping Plover nest fates incorrectly. During the 2013–2015 breeding seasons, we installed miniature surveillance cameras at 65 of 294 Least Tern and 89 of 551 Piping Plover nests under observation on the Missouri River in North Dakota. Nest fates were assigned in the field from remains found at the nest‐site and then again by an independent researcher who reviewed camera footage. We used ordinal logistic regressions to examine whether monitoring interval, clutch age or temporal factors influenced a correct, partially misclassified (probable successful in the field vs. successful by camera) or misclassified nest fate classification. During a 7‐day monitoring interval between visits, 45% of nests were partially and 27.5% were fully misclassified. The percentage of partially (20%) and fully (8.0%) misclassified nests decreased with a more intensive (3‐day) monitoring schedule. Researchers were also less likely to correctly classify nest fates for Least Terns than for Piping Plovers, and as clutch age and monitoring interval increased for both species. Furthermore, causes of failure (e.g. predators, weather) as determined from field evidence vs. video disagreed for 53.5% of nests. The ability to identify accurately nest fate and cause of nest failure will facilitate a better understanding of factors that limit productivity and will lead to better informed management decisions for improving nest survival. 相似文献
4.
KAREL WEIDINGER 《Ibis》2009,151(2):352-360
I used time-lapse videotaping to identify predators of open songbird nests in fragmented deciduous woodland (nine plots, 2–10 ha each) in the Czech Republic from 2002 to 2006. I documented 22 species of predators at 171 nests of 13 species (mainly Blackcap Sylvia atricapilla , Song Thrush Turdus philomelos , Common Blackbird Turdus merula , Yellowhammer Emberiza citrinella and Chaffinch Fringilla coelebs ). The main predators were Pine Marten Martes martes (37% of 178 predation events), Jay Garrulus glandarius (29%), Buzzard Buteo buteo (7%) and Great Spotted Woodpecker Dendrocopos major (7%); mammals accounted for 48% of total predation. At least 3% of nests were depredated by multiple predators. In spite of their local abundance, Hooded Crows Corvus cornix did not present a serious threat for shrub nesting songbirds (< 1% of total predation). No predation by mice was recorded, suggesting that their importance has been overestimated in artificial nest studies. The proportional species composition of predators depended on which species occupied the monitored nest and location (study plot), but not on the year or the time of season. Corvids and raptors accounted for a relatively larger percentage of total predation of small ('warblers') and large ('thrushes') prey species, respectively, whereas carnivores were important predators of all prey species. Active nests of thrushes were only rarely robbed by Jays (< 4% of 52 events), presumably due to parental nest defence. Predation by woodpeckers was spatially clumped, probably due to individual foraging specialization. Predation by the other major predators was documented on most/all study plots. 相似文献
5.
为了了解保护区内外的白冠长尾雉繁殖生态,2014年3—7月在河南董寨国家级自然保护区和保护区外湖北平靖关村利用人工巢试验(以鸡蛋为诱饵)、红外相机技术和栖息地样方调查搜集巢捕食信息,对其巢捕食率、巢潜在捕食者和影响巢捕食的栖息地因子进行研究.两轮试验分别为繁殖期前期3—4月和繁殖期中期5—6月.试验共放置巢149个,其中红外相机监测62个,累计相机日1315个,拍摄照片7776张,视频6950个.结果表明: 保护区外(平靖关)巢捕食率高于保护区内(董寨),繁殖期前期和繁殖期中期保护区内外差异均极显著.平靖关捕食者种类数(11和6种)在繁殖期前期和中期均高于董寨(7和5种),平靖关捕食者比例较高的是啮齿类和鸦科鸟类,董寨捕食比例较高的是貉.平靖关坡度和乔木盖度对巢捕食影响显著,而董寨的落叶盖度对其影响显著.在红外监测的人工巢中共发现野生白冠长尾雉访问人工巢13巢18次. 相似文献
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Karel Weidinger 《Journal of Field Ornithology》2006,77(4):357-364
ABSTRACT. Accurate determination of nest fates and nest predators is possible through continuous video monitoring, but such monitoring is relatively expensive and labor intensive. If documenting of the timing of nest termination events is sufficient, then data loggers (DL) may allow more extensive sampling and may represent a viable alternative. I validated temperature DL records of nest survival time by simultaneous videotaping and compared results derived from DL records with those obtained by regular nest visits by an observer. I estimated the fate of 937 nests of nine species of open cup-nesting songbirds, including 673 nests monitored using DL, 165 monitored using video cameras, 33 validation nests monitored simultaneously using both DL and video cameras, and 132 control nests monitored only by observer visits. Deployment of DL did not negatively influence nest survival rate. DL reliably recorded survival time and allowed classification of nest fates based on the potential fledging age, regardless of the frequency of nest visits by an observer. The true fate of nests that survived beyond the potential fledging age can not be safely determined from time of failure, except for nocturnal events that suggest partial predation. Video revealed frequent partial or complete predation on nests with old nestlings that would have been categorized as successful by other methods. I conclude that temperature DL are efficient, reliable, and relatively inexpensive tools for recording exact nest survival times and classification of nest fates, with implications for nest survival modeling and discriminating between diurnal and nocturnal predation. 相似文献
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Tara J. Conkling Theresa L. Pope Kathryn N. Smith Heather A. Mathewson Michael L. Morrison R. Neal Wilkins James W. Cain III 《The Journal of wildlife management》2012,76(7):1401-1411
Nest predation is a major limiting factor for songbird productivity, including the federally endangered black-capped vireo (Vireo atricapilla). However, nest predator information is limited across the range of the black-capped vireo in central and southwest Texas. We monitored nests in 3 counties within the breeding range of black-capped vireos in Texas in 2008 and 2009 and used continuous recording digital video cameras to record predation events. We video-monitored 115 nests and documented 39 predation events by at least 9 predator species. Overall, we observed avian species (51%, n = 39), specifically brown-headed cowbirds (Molothrus ater; n = 12), and snakes (26%, n = 39) as the most frequent nest predators. The estimated daily nest survival rate during the laying and incubation stage was 0.985 (95% CI = 0.967–0.993) and 0.944 (95% CI = 0.921–0.961) during the nestling stage. In addition, we analyzed models of predator-specific nest predation using multinomial logistic regression. Effect of nest height on predation rate was significant for snakes; nest stage was significant for nests depredated by avian predators. By identifying and increasing our knowledge of nest predators and vegetation characteristics associated with greater risk of predation in multiple locations within the black-capped vireo's range, we can effectively manage habitat to benefit recovery efforts of the species. © 2012 The Wildlife Society. 相似文献
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T. WILL RICHARDSON THOMAS GARDALI STEPHEN H. JENKINS 《The Journal of wildlife management》2009,73(2):287-293
ABSTRACT Identifying nest predators is critical to understanding predation pressures that birds face, and using surveillance cameras appears to be the most reliable method of nest predator identification. However, presence and methods of using camera equipment may introduce bias in predation rates. To summarize potential effects of cameras on nest success we reviewed published and unpublished studies that estimated daily nest predation for bird nests with and without surveillance cameras. We used meta-analyses to quantitatively synthesize the direction and magnitude of these effects from independent studies. We found evidence that, on average, use of camera equipment may reduce nest predation rates, although these differences were not always significant and varied relative to geographic regions, vegetation types, and study duration. Researchers using camera surveillance to monitor nests must be aware that the equipment may be affecting rates of predation and possibly biasing data collected on predator identity. Based on our review and analysis, we provide recommendations for researchers seeking to minimize or control for potential bias when using surveillance cameras to monitor nest predation. 相似文献
10.
Peter S. Coates John W. Connelly David J. Delehanty 《Journal of Field Ornithology》2008,79(4):421-428
ABSTRACT Nest predation is the primary cause of nest failure for Greater Sage‐Grouse (Centrocercus urophasianus), but the identity of their nest predators is often uncertain. Confirming the identity of these predators may be useful in enhancing management strategies designed to increase nest success. From 2002 to 2005, we monitored 87 Greater Sage‐Grouse nests (camera, N= 55; no camera, N= 32) in northeastern Nevada and south‐central Idaho and identified predators at 17 nests, with Common Ravens (Corvus corax) preying on eggs at 10 nests and American badgers (Taxidea taxis) at seven. Rodents were frequently observed at grouse nests, but did not prey on grouse eggs. Because sign left by ravens and badgers was often indistinguishable following nest predation, identifying nest predators based on egg removal, the presence of egg shells, or other sign was not possible. Most predation occurred when females were on nests. Active nest defense by grouse was rare and always unsuccessful. Continuous video monitoring of Sage‐Grouse nests permitted unambiguous identification of nest predators. Additional monitoring studies could help improve our understanding of the causes of Sage‐Grouse nest failure in the face of land‐use changes in the Intermountain West. 相似文献
11.
Ariane L. Waldstein 《Journal of Field Ornithology》2012,83(3):302-305
ABSTRACT A variety of pole‐mounted cameras have been developed for monitoring nest cavities. However, currently available camera systems may either be prohibitively expensive or difficult to assemble. I developed an inexpensive (<$500 US) and easily assembled camera system that allows researchers to monitor cavity nests from the ground. The system consists of a small camera, a cable connecting the camera to a ground‐level power source and laptop computer, and a flexible neck connecting the camera to a telescoping pole. During a study of Red‐headed Woodpeckers (Melanerpes erythrocephalus), I used this camera to inspect 16 nests and found that the images were clear and allowed accurate counts of eggs and nestlings. This camera system uses standard, off‐the‐shelf components, and can easily be altered. The design is not appropriate for humid or dense‐canopy environments because of the inclusion of a laptop and its wired design. However, this design makes the system inexpensive and allows researchers to save, edit, and view nest inspection recordings. 相似文献
12.
ABSTRACT Nest predation is a natural component of greater sage-grouse (Centrocercus urophasianus) reproduction, but changes in nesting habitat and predator communities may adversely affect grouse populations. We used a 2-part approach to investigate sage-grouse nest predation. First, we used information criteria to compare nest survival models that included indices of common raven (Corvus corax) abundance with other survival models that consisted of day of incubation, grouse age, and nest microhabitat covariates using measurements from 77 of 87 sage-grouse nests. Second, we used video monitoring at a subsample of 55 of 87 nests to identify predators of depredated nests (n = 16) and evaluated the influence of microhabitat factors on the probability of predation by each predator species. The most parsimonious model for nest survival consisted of an interaction between day of incubation and abundance of common ravens (wravenXincubation day = 0.67). An estimated increase in one raven per 10-km transect survey was associated with a 7.4% increase in the odds of nest failure. Nest survival was relatively lower in early stages of incubation, and this effect was strengthened with increased raven numbers. Using video monitoring, we found the probability of raven predation increased with reduced shrub canopy cover. Also, we found differences in shrub canopy cover and understory visual obstruction between nests depredated by ravens and nests depredated by American badgers (Taxidea taxus). Increased raven numbers have negative effects on sage-grouse nest survival, especially in areas with relatively low shrub canopy cover. We encourage wildlife managers to reduce interactions between ravens and nesting sage-grouse by managing raven populations and restoring and maintaining shrub canopy cover in sage-grouse nesting areas. 相似文献
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ABSTRACT. Nest predation is the primary cause of nest failure in most passerine birds, and increases in nest predation associated with anthropogenic habitat disturbance are invoked as explanations for population declines of some bird species. In most cases, however, the identity of the nest predators is not known with certainty. We monitored active bird nests with infrared time-lapse video cameras to determine which nest predators were responsible for depredating bird nests in northern New Hampshire. We monitored 64 nests of 11 bird species during three breeding seasons, and identified seven species of predators during 14 predation events. In addition, we recorded two instances of birds defending nests from predators and, in both cases, these nests were ultimately lost to predation. These results contrast with other studies in terms of the relatively high proportion of nests depredated by raptors and mice, as well as the absence of any predation by snakes. The diverse suite of predators in this and other studies is likely to confound our understanding of patterns of nest predation relative to fragmentation and habitat structure. 相似文献
14.
Qaim Naqvi Patrick J. Wolff Brenda Molano&#x;Flores Jinelle H. Sperry 《Ecology and evolution》2022,12(6)
Insect and pollinator populations are vitally important to the health of ecosystems, food production, and economic stability, but are declining worldwide. New, cheap, and simple monitoring methods are necessary to inform management actions and should be available to researchers around the world. Here, we evaluate the efficacy of a commercially available, close‐focus automated camera trap to monitor insect–plant interactions and insect behavior. We compared two video settings—scheduled and motion‐activated—to a traditional human observation method. Our results show that camera traps with scheduled video settings detected more insects overall than humans, but relative performance varied by insect order. Scheduled cameras significantly outperformed motion‐activated cameras, detecting more insects of all orders and size classes. We conclude that scheduled camera traps are an effective and relatively inexpensive tool for monitoring interactions between plants and insects of all size classes, and their ease of accessibility and set‐up allows for the potential of widespread use. The digital format of video also offers the benefits of recording, sharing, and verifying observations. 相似文献
15.
MICHAEL J. RADER TRENT W. TEINERT LEONARD A. BRENNAN FIDEL HERNÁNDEZ NOVA J. SILVY X. BEN WU 《The Journal of wildlife management》2007,71(5):1626-1630
Abstract: Predation is the primary cause of nest failure for northern bobwhites (Colinus virginianus). There are few reliable data documenting the species diversity and relative importance of bobwhite nest predators in southern Texas, USA. We used infrared video-monitoring systems to document nest fates of 127 bobwhite nests over 4 nesting seasons from 2002 to 2005 in southern Texas. A majority of depredation events (83%) were caused by 4 species: coyote (Canis latrans), striped skunk (Mephitis mephitis), southern fire ant (Solenopsis xyloni), and badger (Taxidea taxus). Observed bobwhite nest fates for the study period were 0.50 successful, 0.34 depredated, and 0.16 abandoned or undetermined. A universal approach to mitigating nest predation is not likely to be applicable in regions similar to southern Texas, with high nest-predator diversity (e.g., fire ants, rodents, and mammalian carnivores). We believe that infrared video surveillance is a valuable tool for documenting baseline information on predator context and nest fate for many avian species, considering the limitations of past methods (e.g., postfate evidence). 相似文献
16.
ABSTRACT. In studies of avian nest success, investigators often face the difficult task of periodically checking nest status while at the same time limiting observer influence on nest survival. Remotely monitoring nests using temperature data loggers is one method that allows for continuous data capture regarding nest status (i.e., active vs. inactive) without the negative effects associated with repeated nest checks. We used small temperature data loggers (Thermochron iButtons) to remotely monitor nests of Long-billed Curlews ( Numenius americanus ) in northeastern Nevada. Data loggers programmed to record temperature at 10-min and 20-min intervals were placed in curlew nests. Data loggers were set to collect data throughout the nesting cycle to determine onset of incubation and timing of nest failure. On average, Long-billed Curlews began incubating approximately 3 d after the first egg was laid and onset of incubation coincided with the laying of the third egg. iButtons allowed us to determine when incubation was terminated in 17 of 23 unsuccessful Long-billed Curlew nests, including 13 of 17 depredated nests. The presence of iButtons in Long-billed Curlew nests did not affect daily survival rate, egg hatchability or rate of nest abandonment. iButtons are an efficient and practical means for remotely monitoring nests of large egg-laying birds, such as the Long-billed Curlew. 相似文献
17.
James Mickley 《Ecology and evolution》2017,7(13):4592-4598
The study of animals in the wild offers opportunities to collect relevant information on their natural behavior and abilities to perform ecologically relevant tasks. However, it also poses challenges such as accounting for observer effects, human sensory limitations, and the time intensiveness of this type of research. To meet these challenges, field biologists have deployed camera traps to remotely record animal behavior in the wild. Despite their ubiquity in research, many commercial camera traps have limitations, and the species and behavior of interest may present unique challenges. For example, no camera traps support high‐speed video recording. We present a new and inexpensive camera trap system that increases versatility by separating the camera from the triggering mechanism. Our system design can pair with virtually any camera and allows for independent positioning of a variety of sensors, all while being low‐cost, lightweight, weatherproof, and energy efficient. By using our specialized trigger and customized sensor configurations, many limitations of commercial camera traps can be overcome. We use this system to study hummingbird feeding behavior using high‐speed video cameras to capture fast movements and multiple sensors placed away from the camera to detect small body sizes. While designed for hummingbirds, our application can be extended to any system where specialized camera or sensor features are required, or commercial camera traps are cost‐prohibitive, allowing camera trap use in more research avenues and by more researchers. 相似文献
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许誉馨;冯艳民;郑元斌;郭艺;马雪峰;饶晓东 《生态学杂志》2025,44(3):946-953
繁殖是鸟类生活史的重要环节;巢捕食被认为是影响鸟类生活史特征的生态因子之一。准确估测鸟类的繁殖成功率;掌握巢捕食及其影响因子对了解其种群动态具有重要意义。本研究于2021年和2022年两个繁殖期;对海口地区人工巢箱内繁殖的鹊鸲（Copsychus saularis）的繁殖生态以及巢捕食进行了研究。结果表明:（1）鹊鸲最早产卵日期为3月19日;最晚产卵时间为7月4日;窝卵数（4.47±0.57）枚（n=57）;孵化期（13.30±1.47）d（n=33）;卵重（2.28±0.65）g（n=25）;卵长径和短径分别为（22.21±0.84）mm和（16.38±0.37）mm（n=25）;日坐巢率70.85%±5.92%（n=40）;不同时间段内坐巢时长无显著性差异（F=0.479, df=5, P=0.820）;（2）育雏期（13.32±1.18）d（n=37）;不同时间段内亲鸟喂食次数存在显著差异（F=19.832,df=14, P<0.05）;05:00—06:00（P=0.023）和18:00—19:00（P=0.043）时段喂食次数明显小于其他时段;（3）繁殖成功率为69.49%;孵化率为73.36%;出飞率为73.16%;繁殖力为2.36只;（4）巢捕食率为18.64%;主要巢捕食者包括隐纹花松鼠（Tamiops swinhoei）、黄胸鼠（Rattus tanezumi）和蚁类（Formicidae spp.）等。本研究记录到鹊鸲的清巢行为和非亲雄性杀雏案例;为后续探究鹊鸲的性选择研究奠定了基础。 相似文献
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Joseph Mwangi Henry K. Ndithia Rosemarie Kentie Muchane Muchai B. Irene Tieleman 《Journal of avian biology》2018,49(8)
Nest survival is critical to breeding in birds and plays an important role in life‐history evolution and population dynamics. Studies evaluating the proximate factors involved in explaining nest survival and the resulting temporal patterns are biased in favor of temperate regions. Yet, such studies are especially pertinent to the tropics, where nest predation rates are typically high and environmental conditions often allow for year‐round breeding. To tease apart the effects of calendar month and year, population‐level breeding activity and environmental conditions, we studied nest survival over a 64‐month period in equatorial, year‐round breeding red‐capped larks Calandrella cinerea in Kenya. We show that daily nest survival rates varied with time, but not in a predictable seasonal fashion among months or consistently among years. We found negative influences of flying invertebrate biomass and rain on nest survival and higher survival of nests when nests were more abundant, which suggests that nest predation resulted from incidental predation. Although an increase in nest predation is often attributed to an increase in nest predators, we suggest that in our study, it may be caused by altered predator activity resulting from increased activity of the primary prey, invertebrates, rather than activity of the red‐capped larks. Our results emphasize the need to conduct more studies in Afro‐tropical regions because proximate mechanisms explaining nest predation can be different in the unpredictable and highly variable environments of the tropics compared with the relatively predictable seasonal changes found in temperate regions. Such studies will aid in better understanding of the environmental influences on life‐history variation and population dynamics in birds. 相似文献