scholarly journals Evaluating the utility of camera traps in field studies of predation

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6487 ◽  
Author(s):  
Christopher K. Akcali ◽  
Hibraim Adán Pérez-Mendoza ◽  
David Salazar-Valenzuela ◽  
David W. Kikuchi ◽  
Juan M. Guayasamin ◽  
...  
Keyword(s):  
Observational Data ◽  
Video Recording ◽  
Field Studies ◽  
Camera Traps ◽  
Relative Fitness ◽  
Natural Habitats ◽  
Predator Species ◽  
Additional Information ◽  
Relative Contribution ◽  
Mammalian Predators

Artificial prey techniques—wherein synthetic replicas of real organisms are placed in natural habitats—are widely used to study predation in the field. We investigated the extent to which videography could provide additional information to such studies. As a part of studies on aposematism and mimicry of coral snakes (Micrurus) and their mimics, observational data from 109 artificial snake prey were collected from video-recording camera traps in three locations in the Americas (terra firme forest, Tiputini Biodiversity Station, Ecuador; premontane wet forest, Nahá Reserve, Mexico; longleaf pine forest, Southeastern Coastal Plain, North Carolina, USA). During 1,536 camera days, a total of 268 observations of 20 putative snake predator species were recorded in the vicinity of artificial prey. Predators were observed to detect artificial prey 52 times, but only 21 attacks were recorded. Mammals were the most commonly recorded group of predators near replicas (243) and were responsible for most detections (48) and attacks (20). There was no difference between avian or mammalian predators in their probability of detecting replicas nor in their probability of attacking replicas after detecting them. Bite and beak marks left on clay replicas registered a higher ratio of avian:mammalian attacks than videos registered. Approximately 61.5% of artificial prey monitored with cameras remained undetected by predators throughout the duration of the experiments. Observational data collected from videos could provide more robust inferences on the relative fitness of different prey phenotypes, predator behavior, and the relative contribution of different predator species to selection on prey. However, we estimate that the level of predator activity necessary for the benefit of additional information that videos provide to be worth their financial costs is achieved in fewer than 20% of published artificial prey studies. Although we suggest future predation studies employing artificial prey to consider using videography as a tool to inspire new, more focused inquiry, the investment in camera traps is unlikely to be worth the expense for most artificial prey studies until the cost:benefit ratio decreases.

scholarly journals Evaluating the Impact of Two Generalist Predators on the Leafhopper Erasmoneura vulnerata Population Density

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 321
Author(s):  
Stefan Cristian Prazaru ◽  
Giulia Zanettin ◽  
Alberto Pozzebon ◽  
Paola Tirello ◽  
Francesco Toffoletto ◽  
...  
Keyword(s):  
Field Experiments ◽  
Field Studies ◽  
Generalist Predators ◽  
Predator Species ◽  
Potted Plants ◽  
Naturally Occurring ◽  
Orius Majusculus ◽  
Limited Effectiveness ◽  
Pest Outbreaks ◽  
The Impact

Outbreaks of the Nearctic leafhopper Erasmoneura vulnerata represent a threat to vinegrowers in Southern Europe, in particular in North-eastern Italy. The pest outbreaks are frequent in organic vineyards because insecticides labeled for organic viticulture show limited effectiveness towards leafhoppers. On the other hand, the naturally occurring predators and parasitoids of E. vulnerata in vineyards are often not able to keep leafhopper densities at acceptable levels for vine-growers. In this study, we evaluated the potential of two generalist, commercially available predators, Chrysoperla carnea and Orius majusculus, in suppressing E. vulnerata. Laboratory and semi-field experiments were carried out to evaluate both species’ predation capacity on E. vulnerata nymphs. The experiments were conducted on grapevine leaves inside Petri dishes (laboratory) and on potted and caged grapevines (semi-field); in both experiments, the leaves or potted plants were infested with E. vulnerata nymphs prior to predator releases. Both predator species exhibited a remarkable voracity and significantly reduced leafhopper densities in laboratory and semi-field experiments. Therefore, field studies were carried out over two growing seasons in two vineyards. We released 4 O. majusculus adults and 30 C. carnea larvae per m2 of canopy. Predator releases in vineyards reduced leafhopper densities by about 30% compared to the control plots. Results obtained in this study showed that the two predators have a potential to suppress the pest density, but more research is required to define appropriate predator–prey release ratios and release timing. Studies on intraguild interactions and competition with naturally occurring predators are also suggested.

scholarly journals University campuses can contribute to wildlife conservation in urbanizing regions: a case study from Nigeria

2020 ◽  
Vol 12 (13) ◽  
pp. 16736-16741
Author(s):  
Iliyasu Simon ◽  
Jennifer Che ◽  
Lynne Baker
Keyword(s):  
Habitat Use ◽  
Wildlife Conservation ◽  
Energy Use ◽  
Predictor Variable ◽  
Camera Traps ◽  
Future Research ◽  
Natural Habitats ◽  
University Campuses ◽  
Disturbed Areas ◽  
Cricetomys Gambianus

Globally, colleges and universities are increasingly mandating sustainability and environmental protection into their practices.  To date, such institutions have focused their efforts on recycling and energy-use reduction and less on the management and conservation of wildlife and wildlife habitats. However, in an increasingly urbanizing world, well-managed campuses can provide habitat and even refuge for wildlife species.  On the campus of a sustainability-minded university in Nigeria, we used camera traps to determine the presence of wildlife and used occupancy modeling to evaluate factors that influenced the detectability and habitat use of two mammals for which we had sufficient detections: White-tailed Mongoose Ichneumia albicauda and Gambian Rat Cricetomys gambianus.  Our intent was to gather baseline data on campus wildlife to inform future research and make recommendations for maintaining wildlife populations.  We detected wildlife primarily within less-disturbed areas that contained a designated nature area, and the presence of a nature area was the key predictor variable influencing habitat use.  No measured variables influenced detectability.  This study supports other research that highlights the importance of undisturbed or minimally disturbed natural habitats on university campuses for wildlife, especially in increasingly built-up and developed regions.  We recommend that institutions of higher education devote greater resources to making campuses wildlife-friendly and increase opportunities for students to engage in campus-based wildlife research and conservation and other sustainability-related programs. 

scholarly journals Dieta, uso de hábitat y patrones de actividad del puma (Puma concolor) y el jaguar (Panthera onca) en la selva maya.

2008 ◽  
Vol 12 (1) ◽  
pp. 113 ◽  
Author(s):  
Christian Giovanii Estrada Hernández
Keyword(s):  
Habitat Use ◽  
Puma Concolor ◽  
Activity Patterns ◽  
Camera Traps ◽  
Panthera Onca ◽  
Lowland Forest ◽  
Predator Species ◽  
La Selva ◽  
Mayan Forest ◽  
Niche Components

RESUMEN: La Selva Maya es el bosque tropical de hoja ancha más extenso de Centroamérica, se extiende entre México, Guatemala y Belice. El jaguar y el puma, son los felinos más grandes de América. En esta zona viven simpátricamente por lo que se presupone segregación en alguno de los componentes de su nicho ecológico. En este estudio se analizaron y compararon tres de los componentes principales del nicho: dieta, uso de hábitat y patrones de actividad, con el objetivo de evaluar si existe segregación entre el jaguar y el puma. Para la obtención de los datos se colectaron excrementos de manera oportunista, y se utilizaron trampas de cámaras automáticas en cuatro áreas protegidas. Se analizo la zona de estudio, a través de sistemas de información geográfica para determinar las proporciones de distintos tipos de hábitat presentes, y se colectaron datos de abundancias de las presas. Se analizaron los patrones y en la dieta, en el hábitat utilizado y en el horario de actividad. Se determino que el jaguar tuvo una dieta diferente y mas amplia comparada con la del puma, así también que este consume en promedio, presas más pequeñas. Las presas preferidas por elpuma fueron, tres especies de venados y tepezcuintles. Para el jaguar fueron coches de monte, pizotes y armadillos. Ambas especies presentaron un patrón similar de uso de hábitat, donde el "bosque alto" fue utilizado proporcionalmente a su abundancia, y el puma evitó el "bosque bajo". En cuanto a los patrones de actividad, ambos prefirieron horas nocturnas para desplazarse, aunque el puma presento mayor variabilidad. Se observo que ambas especies no se segregan mutuamente, espacial ni temporalmente. La frecuente utilización del "bosque bajo" y su relación con las aguadas y arroyos, es un factor importante en el mantenimiento de poblaciones de grandes felinos en la Selva MayaPALABRAS CLAVE: Felidae, Panthera onca, Puma concolor, coexistencia, nicho ecológico, Selva Maya, segregación ecológica.ABSTRACT: The Mayan Forest is the largest tropical broad-leaf forest remainder in Central America which extends between Mexico, Guatemala and Belize. Jaguar and puma are the biggest American wild cats. In this area both live sympatric which suggest segregation in at least one of its ecological niche components. In this study I analyzed and compared three of the principal niche components: diet, habitat use and activity patterns, with the main objective of assess if occurs ecological segregation among jaguar and puma. To obtain the data it was collected  jaguar and puma’s scats in an opportunistic way, and was used automatic camera traps in four protected areas. I analyzed the study area by geographic information system (GIS) to determine proportions of different habitat types, and also I used  previous collected prey abundance data. I analyzed patterns in diet, in habitat use and temporal activity. I found that jaguar had a wider prey spectrum than puma; jaguar took (in average) smallest preys, consequently, diets were significantly different. Puma preferred deer, brocket deer and paca as main prey; in contrast, jaguar preferred collared pecari, coati and armadillo. Both predator species presented a similar pattern in habitat usage, in which "highland forest" was used accordingly with its availability and puma avoided "lowland forest". About activity patterns, both were more active in the night time, however, puma was more variable in this aspect. Both species did not show segregation spatially or temporally. KEYWORDS: Felidae, Panthera onca, Puma concolor, coexistence, ecologic niche, Mayan forest, ecologic segregation.

Novelty at dawn: Exploration, low neophobia and crepuscular activity in a wild Common Buzzard (Buteo buteo)

2021 ◽  
pp. 175815592110524
Author(s):  
Berenika Mioduszewska ◽  
Mark O’Hara ◽  
Rafał Stryjek
Keyword(s):  
Foraging Ecology ◽  
Natural Habitat ◽  
Field Studies ◽  
Field Method ◽  
Cognitive Testing ◽  
Research Attention ◽  
Predator Species ◽  
Common Buzzard ◽  
Buteo Buteo ◽  
Free Ranging

Raptor cognition has received limited research attention, despite the importance of comparative investigations for reconstructing the evolution of complex cognition. Field studies provide essential ecological context for cognition in the natural habitat, although this approach is often challenging due to extensive procedures involved in cognitive testing. One predisposition suggested to contribute to problem-solving behaviour is the response to novel stimuli. In this pilot study, a novel object test was conducted on an outdoor feeding platform to assess the neotic responses of a single wild free-ranging Common Buzzard ( Buteo buteo), a generalist/opportunist diurnal predator species. Additionally, data on its daily activity were collected. As predicted, the subject expressed low neophobia and some exploratory behaviours. Interestingly, it repeatedly arrived on the platform in low light conditions. This study highlights the influence of foraging ecology on cognitive predispositions and offers a field method for research on raptor cognition.

Update of the volcanic sulfur emission inventory in MOCAGE CTM and its impact on the budget of sulfur species in the atmosphere

2020 ◽  
Author(s):  
Claire Lamotte ◽  
Virginie Marécal ◽  
Jonathan Guth
Keyword(s):  
Sulfur Dioxide ◽  
Chemical Species ◽  
Global Scale ◽  
Satellite Observations ◽  
Emission Inventories ◽  
Sulfur Species ◽  
Additional Information ◽  
Relative Contribution ◽  
Global Increase ◽  
The Impact

<p>Constraining emission inventories into chemistry-transport models (CTM) is essential. In addition to anthropogenic emissions, natural sources of pollutants must be considered. Among them, volcanoes are large emitters of gases, including sulfur dioxide (SO<sub>2</sub>), a volatile species, causing environmental and health issues.</p><p>Volcanic SO<sub>2</sub> emission inventories are usually integrated in global CTMs, in order to improve the modelling of chemical species in the atmosphere. Here, we use the model MOCAGE, developed at CNRM, which currently uses Andres & Krasgnoc’s inventory (1998); a temporal average of emission on some 40 volcanoes, monitored through the synergy of satellite data and surface remote sensing instruments, for 25 years (from 1970’s to 1997). However, this inventory is now quite old and is therefore no longer sufficiently accurate.</p><p>Thanks to the development of new satellite observations, it has become possible to produce such inventories with an improved accuracy. The global coverage and higher sensitivity of these instruments has allowed to reference more emission sources (hard-to-access volcanoes, small eruptions or even passive degassing). Hence, a new inventory of Carn et al (2016,2017) based on satellite observations has been implemented in MOCAGE. Besides being recent (from 1978 up to 2015), it combines eruption and passive degassing over more than 160 volcanoes. Passive degassing fluxes are provided as annual averages and eruption fluxes as daily total quantities (in case of events). In addition, information on volcanoes vent altitude and eruptive plume heights is available, which has been used to better constraints the model.</p><p>We focus our study at the global scale. The years 2013 and 2014 were chosen as the years with the lowest and highest total eruptive emissions respectively, in Carn's inventory. Thus, 2013 highlights mainly the impact of passive degassing, while 2014 provides additional information on eruptions.</p><p>For each of the years studied, the sulfur species budget in MOCAGE simulation is increased when the inventory is updated and therefore the relative contribution of volcanic sulfur emissions is larger. We note the global increase in sulfur dioxide and sulfate aerosol burdens; an increase even more significant when the injection heights of the emissions are taken into account.</p>

scholarly journals Testing camera traps as a potential tool for detecting nest predation of birds in a tropical rainforest environment

2018 ◽  
Vol 35 ◽  
pp. 1-8 ◽  
Author(s):  
Laís Ribeiro-Silva ◽  
Daniel Fernandes Perrella ◽  
Carlos Biagolini-Jr ◽  
Paulo Zima ◽  
Augusto J. Piratelli ◽  
...  
Keyword(s):  
Nest Predation ◽  
Tropical Rainforest ◽  
Size Range ◽  
Bird Species ◽  
Camera Trap ◽  
Camera Traps ◽  
Predator Species ◽  
Set Up ◽  
Monitoring Devices ◽  
Potential Tool

Identification of the predators of bird nests is essential to test ecological and evolutionary hypotheses and to make practical management decisions. A variety of nest monitoring devices have been proposed but many remain difficult to set up in the field. The aim of this study was to test camera traps as a potential tool to study predation of natural nests in a tropical rainforest environment. Specifically, we registered the predators, assessed their size range, and we compared the use of one and two cameras per nest. Of 122 nests from 24 bird species, 45 (37%) were depredated, and the cameras recorded the predator species in 29 of the total of depredated nests (64%). We identified predators in eight of 16 depredated nests (50%) in which we used one camera trap per nest, and we identified predators in 21 of 29 depredated nests (72%) when we used two camera traps per nest. The predators included six species of birds and six species of mammals, with body masses varying from 20 g to 16.5 kg. Causes for 10 of the 16 detection failures were identified and are discussed. These results suggest that camera traps are viable tools to investigate nest predation in a tropical rainforest area.

scholarly journals Land cover and vegetation data from an ecological survey of "key habitat" landscapes in England, 1992–1993

2018 ◽  
Vol 10 (2) ◽  
pp. 899-918
Author(s):  
Claire M. Wood ◽  
Robert G. H. Bunce ◽  
Lisa R. Norton ◽  
Simon M. Smart ◽  
Colin J. Barr
Keyword(s):  
Land Cover ◽  
Natural Habitats ◽  
Yield Data ◽  
Additional Information ◽  
Ecological Changes ◽  
Land Cover Data ◽  
The Status ◽  
Priority Habitat

Abstract. Since 1978, a series of national surveys (Countryside Survey, CS) have been carried out by the Centre for Ecology and Hydrology (CEH) (formerly the Institute of Terrestrial Ecology, ITE) to gather data on the natural environment in Great Britain (GB). As the sampling framework for these surveys is not optimised to yield data on rarer or more localised habitats, a survey was commissioned by the then Department of the Environment (DOE, now the Department for Environment, Food and Rural Affairs, DEFRA) in the 1990s to carry out additional survey work in English landscapes which contained semi-natural habitats that were perceived to be under threat, or which represented areas of concern to the ministry. The landscapes were lowland heath, chalk and limestone (calcareous) grasslands, coasts and uplands. The information recorded allowed an assessment of the extent and quality of a range of habitats defined during the project, which can now be translated into standard UK broad and priority habitat classes. The survey, known as the "Key Habitat Survey", followed a design which was a series of gridded, stratified, randomly selected 1 km squares taken as representative of each of the four landscape types in England, determined from statistical land classification and geological data ("spatial masks"). The definitions of the landscapes are given in the descriptions of the spatial masks, along with definitions of the surveyed habitats. A total of 213 of the 1 km2 square sample sites were surveyed in the summers of 1992 and 1993, with information being collected on vegetation species, land cover, landscape features and land use, applying standardised repeatable methods. The database contributes additional information and value to the long-term monitoring data gathered by the Countryside Survey and provides a valuable baseline against which future ecological changes may be compared, offering the potential for a repeat survey. The data were analysed and described in a series of contract reports and are summarised in the present paper, showing for example that valuable habitats were restricted in all landscapes, with the majority located within protected areas of countryside according to different UK designations. The dataset provides major potential for analyses, beyond those already published, for example in relation to climate change, agri-environment policies and land management. Precise locations of the plots are restricted, largely for reasons of landowner confidentiality. However, the representative nature of the dataset makes it highly valuable for evaluating the status of ecological elements within the associated landscapes surveyed. Both land cover data and vegetation plot data were collected during the surveys in 1992 and 1993 and are available via the following DOI: https://doi.org/10.5285/7aefe6aa-0760-4b6d-9473-fad8b960abd4. The spatial masks are also available from https://doi.org/10.5285/dc583be3-3649-4df6-b67e-b0f40b4ec895.

scholarly journals Testing camera traps as a potential tool for detecting nest predation of birds in a tropical rainforest environment

2018 ◽  
Vol 35 ◽  
pp. 1-8
Author(s):  
Laís Ribeiro-Silva ◽  
Daniel Fernandes Perrella ◽  
Carlos Biagolini-Jr ◽  
Paulo Zima ◽  
Augusto J. Piratelli ◽  
...  
Keyword(s):  
Nest Predation ◽  
Tropical Rainforest ◽  
Size Range ◽  
Bird Species ◽  
Camera Trap ◽  
Camera Traps ◽  
Predator Species ◽  
Set Up ◽  
Monitoring Devices ◽  
Potential Tool

Identification of the predators of bird nests is essential to test ecological and evolutionary hypotheses and to make practical management decisions. A variety of nest monitoring devices have been proposed but many remain difficult to set up in the field. The aim of this study was to test camera traps as a potential tool to study predation of natural nests in a tropical rainforest environment. Specifically, we registered the predators, assessed their size range, and we compared the use of one and two cameras per nest. Of 122 nests from 24 bird species, 45 (37%) were depredated, and the cameras recorded the predator species in 29 of the total of depredated nests (64%). We identified predators in eight of 16 depredated nests (50%) in which we used one camera trap per nest, and we identified predators in 21 of 29 depredated nests (72%) when we used two camera traps per nest. The predators included six species of birds and six species of mammals, with body masses varying from 20 g to 16.5 kg. Causes for 10 of the 16 detection failures were identified and are discussed. These results suggest that camera traps are viable tools to investigate nest predation in a tropical rainforest area.

scholarly journals Extinctions and threats to avifaunas on oceanic islands: Tests of influences of human populations and the filter effect

2015 ◽  
Author(s):  
Heather Zimbler-DeLorenzo ◽  
Bertram Zinner ◽  
Ronald J Scheibel ◽  
F. Stephen Dobson
Keyword(s):  
Population Size ◽  
Threatened Species ◽  
Human Population ◽  
Bird Species ◽  
Oceanic Islands ◽  
Human Populations ◽  
Partial Regression Coefficient ◽  
Predator Species ◽  
Filter Effect ◽  
Mammalian Predators

Extinctions and threats of extinctions in avifaunas on oceanic islands appear to be influenced by several island characteristics and introduced mammalian predators. These predators may have caused a “filter effect”; low numbers of threatened avian species on some islands might be due to high rates of past extinctions. Using path analysis, we examined these factors and the influence of human population size (as an indicator of human activity) on the number of species extinctions and threatened bird species on islands. Human population size had substantial influences on the number of extinctions (standardized partial regression coefficient ρ = 0.315, N = 172, P = 0.0005) but not on the number of threatened species on oceanic islands (ρ = -0.061, P = 0.43), independent of the number of introductions of predator species. The number of extinctions on islands produced a significant filter effect (viz., had a negative impact; ρ = -0.186, P = 0.003) on the number of currently threatened species. The activities of human populations, including mammalian predators they introduced, have likely resulted in a greater number of bird extinctions on these islands, and producing a significant filter effect, wherein islands with larger human populations now have fewer threatened species.

Thuranthos: notes on generic status, morphology, phenology and pollination biology

Bothalia ◽  
1976 ◽  
Vol 12 (1) ◽  
pp. 161-165 ◽  
Author(s):  
C. H. Stirton
Keyword(s):  
South African ◽  
Field Studies ◽  
Pollination Biology ◽  
Fruit Morphology ◽  
The South ◽  
Generic Status ◽  
Additional Information ◽  
Relationship Of ◽  
First Time ◽  
The Relationship

The generic status of Thuranthos C. H. Wr. is discussed. A key separating the two species is provided. The genus is reported to occur in Natal for the first time. Field studies in Natal have yielded additional information on the habitat, phenology, fruit morphology and pollination biology of  T. macranthum (Bak.) C.H. Wr. Phalaenophily is reported for the second time in the South African Liliaceae. The relationship of T. macranthum with the moth  Diaphone eumela (Cramer)—Noctuidae, Hadeniae, is discussed.

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