Motion-sensitive Cameras Research Articles

Development of a low-dose fipronil deer feed: Bait-screening and range-finding to determine the optimal formulation to control blacklegged ticks (Ixodes scapularis) feeding on white-tailed deer (Odocoileus virginianus).

Lyme disease is the most prevalent vector-borne disease in the U.S., and acaricidal feeds administered to white-tailed deer (Odocoileus virginianus) have potential to disrupt blood feeding by the blacklegged tick, Ixodes scapularis. Two studies were conducted with the aim of determining an ideal formulation to deliver oral acaricides to white-tailed deer and finding the lowest fipronil dose level to effectively control I. scapularis. During formulation screening, various commercial attractants (baits) were presented to deer in large paddocks under semi-field conditions and motion-sensitive cameras were used to monitor consumption by deer and non-target species. During dose range-finding, deer were housed individually and presented a fipronil feed at one of five dose levels for 48 h (two deer untreated). At 24 h post-exposure, the deer were anesthetized, blood was drawn, and deer were manually infested with 20 I. scapularis mating pairs in feeding capsules. Tick mortality was monitored up to nine days post-attachment. Results of formulation screening indicated that loose/granular formulations were substantially more palatable to deer, relative to block formulations, and would be more effective under field conditions. Dose range-finding concluded fipronil feeds with doses of 25 ppm and higher would eliminate 100% of I. scapularis parasitizing deer. Additionally, 10 ppm fipronil feed controlled a considerable proportion of ticks, and results suggested 100% ticks could be eliminated if fipronil sulfone was present in plasma at ≥25.1 ppb. These results were paramount in developing a low dose fipronil deer feed for tick control and should provide valuable insights prior to execution of future field trials.

Wild boar visits to commercial pig farms in southwest England: implications for disease transmission

Contact between wild animals and farmed livestock may result in disease transmission with huge financial, welfare and ethical consequences. Conflicts between people and wildlife can also arise when species such as wild boar (Sus scrofa) consume crops or dig up pasture. This is a relatively recent problem in England where wild boar populations have become re-established in the last 20 years following a 500-year absence. The aim of this pilot study was to determine if and how often free-living wild boar visited two commercial pig farms near the Forest of Dean in southwest England. We placed 20 motion-sensitive camera traps at potential entry points to, and trails surrounding, the perimeter of two farmyards housing domestic pigs between August 2019 and February 2021, covering a total of 6030 trap nights. Forty wild boar detections were recorded on one farm spread across 27 nights, with a median (range) of 1 (0 to 7) night of wild boar activity per calendar month. Most of these wild boar detections occurred between ten and twenty metres of housed domestic pigs. No wild boar was detected at the other farm. These results confirm wild boar do visit commercial pig farms, and therefore, there is potential for contact and pathogen exchange between wild boar and domestic pigs. The visitation rates derived from this study could be used to parameterise disease transmission models of pathogens common to domestic pigs and wild boars, such as the African swine fever virus, and subsequently to develop mitigation strategies to reduce unwanted contacts.

Factors influencing seed predation in rainforest tree communities of subtropical Australia: Fragmentation, seed size and shifts in vertebrate assemblages

Rainforest fragmentation has large impacts on ground-active vertebrates, including granivorous mammals (e.g., rodents), and birds. We tested for differences in community-wide patterns of interference with seeds of rainforest trees, between fragments and continuous forest. We also assessed whether these differences were associated with changes in the seed predator communities. Seeds of 20 locally-common tree species were deployed at experimental stations in 12 rainforest sites (six continuous forest and six fragments) across an agricultural landscape in subtropical Australia, where vertebrates rarely cache seeds. Eleven species had small seeds (<10 mm), nine had larger seeds. We recorded seeds' fates after five days. Concurrently, we used automated motion-sensitive cameras to record seed predators' frequencies, and their interactions with seeds. Across all sites and species, 47% of seeds disappeared (varying among species from 17% to 76%), while 6% were partly damaged. Overall rates of disappearance and partial damage did not differ between habitats. However, seeds of five tree species were significantly more heavily predated, and those of five species less predated, in fragments than in continuous forest (10 species not differing significantly). Among-site variation in seed predator species composition was closely associated (r = 0.96) with the multispecies pattern of seed predation, while both differed significantly between continuous forest and fragments. We conclude that rainforest fragmentation strongly influenced patterns of seed mortality, as an indirect consequence of the vertebrate seed predators' responses to habitat fragmentation. In turn, this could induce both increases and decreases in tree species' regeneration rates, and changes in future tree species composition.

Philopatric and natal dispersal of tigers in a semi-arid habitat, western India

The connectivity between landscapes is an important aspect of the conservation of small and isolated populations of carnivores. We studied the natal dispersal pattern of Bengal tigers (Panthera tigris tigris) using motion-sensitive cameras and intensive searches from April 2005 to June 2011 in Ranthambhore Tiger Reserve (RTR), western India. We tracked 29 tiger cubs (18 males, 11 females) born during the study until they established independent territories. All the females and 72.2% of the males attained maturity. The males had a greater probability (92.3%) of dispersal compared with the females (36.4%). Males dispersed an average distance of 27.0 ± 12.7 (SE) km (range = 4.5–148 km), while females dispersed an average distance of 5.7 ± 3.03 km (range = 4.6–25.8 km) from their natal area to establish their independent territories. The average age of dispersal was 38.6 ± 2.6 months (range = 24–44 months) for the males and 27.7 ± 2.7 months (range = 25–33 months) for the females. Seven of the 11 females bred at >48 months’ age, after establishing independent territories. Of the other females, three were translocated to another protected area, and one died after the dispersal. This study adds to the baseline information about the dispersal patterns of tigers, which is important in making conservation and management decisions for restoration of tiger populations.

Applications of Unmanned Aerial Vehicles to Survey Mesocarnivores

With the widespread extirpation of top predators over the past two centuries, mesocarnivores play an increasingly important role in structuring terrestrial trophic webs. However, mesocarnivores are difficult to survey at a population level because their widely spaced territories and nocturnal behavior result in low detection probability. Existing field survey techniques such as track plates and motion-sensitive camera traps are time-consuming and expensive, and yet still yield data prone to systematic errors. Unmanned Aerial Vehicles (UAVs) have recently emerged as a new tool for conducting population surveys on a wide variety of wildlife, eclipsing the efficiency and even accuracy of traditional methods. We used a UAV equipped with a thermal imaging camera to conduct nighttime mesocarnivore surveys in the prairie pothole region of southern Manitoba, Canada. This was part of a much larger ecological study evaluating how lethal removal of mesocarnivores affects duck nest success. Here, our objective was to describe methods and equipment that were successful in detecting mesocarnivores. We used a modified point-count survey from six waypoints that surveyed a spatial extent of 29.5 ha. We conducted a total of 200 flights over 53 survey nights during which we detected 32 mesocarnivores of eight different species. Given the large home ranges of mesocarnivores relative to the spatial and temporal scale of our spot sampling approach, results of these types of point-count surveys should be considered estimates of minimum abundance and not a population census. However, more frequent sampling and advanced statistics could be used to formally estimate population occupancy and abundance. UAV-mounted thermal imaging cameras appear to be an effective tool for conducting nocturnal population surveys on mesocarnivores at a moderate spatial scale.

Characterizations of handwashing sink activities in a single hospital medical intensive care unit

Handwashing sink drains are increasingly implicated as a potential reservoir of antibiotic-resistant bacteria in hospital outbreaks; however, usage patterns that may promote this source remain unknown. To understand behaviours in the intensive care unit (ICU) that may facilitate establishment and nosocomial transmission of multidrug-resistant Gram negatives from a sink-trap reservoir to a patient. Motion-sensitive cameras captured anonymized activity paired with periodic in-person observations during a quality investigation from four ICU sinks (two patient rooms and two patient bathrooms) in a university hospital. We analysed 4810 sink videos from 60 days in patient rooms (3625) and adjoining bathrooms (1185). There was a false-positive rate of 38% (1837 out of 4810) in which the camera triggered but no sink interaction occurred. Of the 2973 videos with analysed behaviours there were 5614 observed behaviours which were assessed as: 37.4% medical care, 29.2% additional behaviours, 17.0% hand hygiene, 7.2% patient nutrition, 5.0% environmental care, 4.2% non-medical care. Handwashing was only 4% (224 out of 5614) of total behaviours. Sub-analysis of 2748 of the later videos further categorized 56 activities where a variety of nutrients, which could promote microbial growth, were disposed of in the sink. Several non-hand hygiene activities took place regularly in ICU handwashing sinks; these may provide a mechanism for nosocomial transmission and promotion of bacterial growth in the drain. Redesigning hospital workflow and sink usage may be necessary as it becomes apparent that sink drains may be a reservoir for transmission of multidrug-resistant bacteria.

Stable isotope mixing models fail to estimate the diet of an avian predator

ABSTRACT Predation can shape community structure, so understanding the diet of predators is an important aspect of ecology. Stable isotope analysis using Bayesian mixing models is a potentially powerful method of estimating diet, but results are often ambiguous. A commonly cited advantage of Bayesian mixing models is the ability to include informative priors, which can improve precision and accuracy of mixing model results. However, factors such as a large number of potential prey and high amounts of variation and correlation among isotopic signatures of prey can lead to imprecise estimate of diet when Bayesian mixing models are used. In this study, we tested the efficacy of using Bayesian mixing models for stable isotopes to estimate the diet of Arctic Peregrine Falcon (Falco peregrinus tundrius) nestlings in Nunavut, Canada, consuming a diversity of terrestrial and marine prey. In addition to stable isotopes, we also estimated diet composition by monitoring peregrine nests with motion-sensitive cameras....

Effects of a protection gradient on carnivore density and survival: an example with leopards in the Luangwa valley, Zambia.

Human activities on the periphery of protected areas can limit carnivore populations, but measurements of the strength of such effects are limited, largely due to difficulties of obtaining precise data on population density and survival. We measured how density and survival rates of a previously unstudied leopard population varied across a gradient of protection and evaluated which anthropogenic activities accounted for observed patterns. Insights into this generalist's response to human encroachment are likely to identify limiting factors for other sympatric carnivore species. Motion‐sensitive cameras were deployed systematically in adjacent, similarly sized, and ecologically similar study areas inside and outside Zambia's South Luangwa National Park (SLNP) from 2012 to 2014. The sites differed primarily in the degree of human impacts: SLNP is strictly protected, but the adjacent area was subject to human encroachment and bushmeat poaching throughout the study, and trophy hunting of leopards prior to 2012. We used photographic capture histories with robust design capture–recapture models to estimate population size and sex‐specific survival rates for the two areas. Leopard density within SLNP was 67% greater than in the adjacent area, but annual survival rates and sex ratios did not detectably differ between the sites. Prior research indicated that wire‐snare occurrence was 5.2 times greater in the areas adjacent to the park. These results suggest that the low density of leopards on the periphery of SLNP is better explained by prey depletion, rather than by direct anthropogenic mortality. Long‐term spatial data from concurrent lion studies suggested that interspecific competition did not produce the observed patterns. Large carnivore populations are often limited by human activities, but science‐based management policies depend on methods to rigorously and quantitatively assess threats to populations of concern. Using noninvasive robust design capture–recapture methods, we systematically assessed leopard density and survival across a protection gradient and identified bushmeat poaching as the likely limiting factor. This approach is of broad value to evaluate the impacts of anthropogenic activities on carnivore populations that are distributed across gradients of protection.

First recorded breeding attempt of Redfooted Booby Sula sula on St Helena Island, South Atlantic

Red-footed Boobies Sula sula are a wide ranging species that used to have a significant breeding population on both Ascension and St Helena Island in the South Atlantic. It was thought that only a small remnant population existed at Ascension Island until now. Five breeding attempts on the southern coastal windward side of St Helena by white morph Red-footed Boobies were recorded using an infra-red motion sensitive camera during 2014–2015. Of the minimum of nine eggs laid, none hatched suggesting more than one female was involved in nesting efforts and they were infertile and/or inexperienced breeders. Theories as to where these birds may have come from are discussed.

North Kimberley Mammals – on the fringe of the high-rainfall zone

Six areas were surveyed for terrestrial fauna during remote hiking expeditions in the Kimberley during 2009, 2010, 2013 and 2014. A total of 19 mammal species were recorded, comprising one introduced and 18 native taxa. Significant populations of the northern quoll, monjon, golden-backed tree-rat and scaly-tailed possum were recorded, including from areas where the species were previously unknown. Fractured, rocky terrain in association with rainforest appears to provide important habitat for these species. The use of motion-sensitive cameras, particularly in areas where foraging signs are evident (tracks, diggings, feeding middens, scats) is shown to be a successful and complementary survey technique in detecting critical-weight-range species in the north Kimberley. Such taxa appear to persist in the far north Kimberley in the absence of several threatening processes attributable to large-scale mammal decline across northern Australia.

Animal scavenging and scattering and the implications for documenting the deaths of undocumented border crossers in the Sonoran Desert.

Since 1998, over 5500 people have died while attempting to cross the U.S.-Mexico border without authorization. These deaths have primarily occurred in the Arizona desert. Despite the high volume of deaths, little experimental work has been conducted on Sonoran Desert taphonomy. In this study, pig carcasses were used as proxies for human remains and placed in different depositional contexts (i.e., direct sunlight and shade) that replicate typical sites of migrant death. Decomposition was documented through daily site visits, motion-sensitive cameras and GIS mapping, while skeletal preservation was investigated through the collection of the remains and subsequent faunal analysis. Our results suggest that vultures and domestic dogs are underappreciated members of the Sonoran scavenging guild and may disperse skeletal remains and migrant possessions over 25 m from the site of death. The impact of scavengers and the desert environment on the decomposition process has significant implications for estimating death rates and identifying human remains along the Arizona/Mexico border.

A new population of the northern quoll (Dasyurus hallucatus) on the edge of the Little Sandy Desert, Western Australia

A fauna survey was conducted within the Throssell and Broadhurst Ranges in the Little Sandy Desert Bioregion of Western Australia during August and September 2012. The endangered northern quoll (Dasyurus hallucatus) was recorded from two distinct locations of similar habitat: deep dissected rocky gorges containing caves and permanent waterholes. One individual was photographed by a motion-sensitive camera and several scats were collected, with mitochondrial DNA analysis confirming the identification. These records represent a significant range extension (~200 km) and due to habitat restrictions are likely to represent the very eastern extreme of the species’ range.

WHITE-NOSE SYNDROME-AFFECTED LITTLE BROWN MYOTIS (MYOTIS LUCIFUGUS) INCREASE GROOMING AND OTHER ACTIVE BEHAVIORS DURING AROUSALS FROM HIBERNATION

White-nose syndrome (WNS) is an emerging infectious disease of hibernating bats linked to the death of an estimated 5.7 million or more bats in the northeastern United States and Canada. White-nose syndrome is caused by the cold-loving fungus Pseudogymnoascus destructans (Pd), which invades the skin of the muzzles, ears, and wings of hibernating bats. Previous work has shown that WNS-affected bats arouse to euthermic or near euthermic temperatures during hibernation significantly more frequently than normal and that these too-frequent arousals are tied to severity of infection and death date. We quantified the behavior of bats during these arousal bouts to understand better the causes and consequences of these arousals. We hypothesized that WNS-affected bats would display increased levels of activity (especially grooming) during their arousal bouts from hibernation compared to WNS-unaffected bats. Behavior of both affected and unaffected hibernating bats in captivity was monitored from December 2010 to March 2011 using temperature-sensitive dataloggers attached to the backs of bats and infrared motion-sensitive cameras. The WNS-affected bats exhibited significantly higher rates of grooming, relative to unaffected bats, at the expense of time that would otherwise be spent inactive. Increased self-grooming may be related to the presence of the fungus. Elevated activity levels in affected bats likely increase energetic stress, whereas the loss of rest (inactive periods when aroused from torpor) may jeopardize the ability of a bat to reestablish homeostasis in a number of physiologic systems.

Intraspecific Adoption and Double Nest Switching in Peregrine Falcons (&lt;i&gt;Falco peregrinus&lt;/i&gt;)

We describe an observation of post-fledging double nest switching and alloparenting in the Peregrine Falcon (Falco peregrinus tundrius). During the summer of 2010, a 36-day-old male Peregrine Falcon that had been marked with leg bands was seen flying from its natal site and was subsequently observed at a neighboring nest site that contained two nestlings. Motion-sensitive camera images indicated that the adopted nestling remained at the neighboring site for several days, during which time it shared the nest ledge with the two resident nestlings and was fed by the adults that occupied the site. The juvenile falcon subsequently returned to its natal site, where it shared the nest ledge with its natural sibling and received care from its natural parents. This note is the first documentation of nest switching in wild Peregrine Falcons.

Brood Reduction by Infanticide in Peregrine Falcons

This note describes an observation of infanticide in the Peregrine Falcon (Falco peregrinus tundrius). During the summer of 2011, a marked adult female and an unmarked adult male produced and hatched two eggs at a known and regularly monitored nest site. Motion-sensitive camera images indicated that the adults attended to the two nestlings and fed them in a manner that resulted in growth and development typical for the nestlings produced in the study population. During a period of intense rainfall, the two nestlings were left unattended for several hours; both nestlings were clearly distressed, and one was close to death. When the visibly wet marked adult female returned to the nest ledge, she killed and partially consumed the smaller and weaker of the two nestlings. The female flew from the nest ledge without feeding the remaining nestling and returned shortly afterward to kill and partially consume the second nestling. This is the first documentation of infanticide in wild Peregrine Falcons.

A comparison of methods for monitoring kit foxes at den sites

Monitoring mammalian carnivores at den sites with human observers to document behavior, fecundity, litter size, and natal survival is commonplace when compared with monitoring den sites with cameras. However, no published studies exist comparing the effectiveness of human observers versus cameras in a quantitative manner. Obtaining complete and reliable counts of adult and pup kit foxes (Vulpes macrotis) can be crucial for estimating population parameters and life-history traits. In the summers of 2010 and 2011, we made weekly counts of adult and pup kit foxes at active den sites using 2 methods: 1) an observer equipped with spotting scope and/or binoculars and 2) a remote infrared motion-sensitive camera. We accumulated 71 and 29 counts at active den sites, respectively. The median number of adults observed at den sites with a camera and observer differed and were 2 adults versus 1 adult, respectively. Similarly, the median number of pups observed at den sites with a remote camera versus an observer differed and was 2 pups versus 1 pup, respectively. We observed these differences despite the similar effort required to manage cameras and conduct observations. We recommend future surveys aimed at ascertaining more reliable counts of kit foxes and similar species at den sites use a survey methodology employing remote cameras or video over a multi-day period. 2013 The Wildlife Society.

Radar Tracking and Motion-Sensitive Cameras on Flowers Reveal the Development of Pollinator Multi-Destination Routes over Large Spatial Scales

Author SummaryMany food resources, such as flowers refilling with nectar or fruits ripening on a tree, replenish over time, so animals that depend on them need to develop strategies to reduce the energy they use during foraging. Here we placed five artificial flowers in a field and set out to examine how bumblebees optimize their foraging routes between distant locations. We tracked the flight paths of individual bees with harmonic radar and recorded all their visits to flowers with motion-sensitive video cameras. This dataset allowed us to study how bees gradually discover flowers, learn their exact position in the landscape, and then find the shortest route to collect nectar from each flower in turn. Using computer simulations, we show that the level of optimisation performance shown by bees can be replicated by a simple learning algorithm that could be implemented in a bee brain. We postulate that this mechanism allows bumblebees to optimise their foraging routes in more complex natural conditions, where the number and productivity of flowers vary.

Invariant principles of speech motor control that are not language-specific

Bilingual speakers must learn to modify their speech motor control mechanism based on the linguistic parameters and rules specified by the target language. This study examines if there are aspects of speech motor control which remain invariant regardless of the first (L1) and second (L2) language targets. Based on the age of academic exposure and proficiency in L2, 21 Bengali–English bilingual participants were classified into high (n = 11) and low (n = 10) L2 (English) proficiency groups. Using the Optotrak 3020 motion sensitive camera system, the lips and jaw movements were recorded while participants produced Bengali (L1) and English (L2) sentences. Based on kinematic analyses of the lip and jaw movements, two different variability measures (i.e., lip aperture and lower lip/jaw complex) were computed for English and Bengali sentences. Analyses demonstrated that the two groups of bilingual speakers produced lip aperture complexes (a higher order synergy) that were more consistent in co-ordination than were the lower lip/jaw complexes (a lower order synergy). Similar findings were reported earlier in monolingual English speakers by Smith and Zelaznik. Thus, this hierarchical organization may be viewed as a fundamental principle of speech motor control, since it is maintained even in bilingual speakers.

Non-overlapping Distributions of Feral Sheep (Ovis aries) and Stout Iguanas (Cyclura pinguis) on Guana Island, British Virgin Islands

&#x0D; &#x0D; &#x0D; &#x0D; Stout Iguanas (Cyclura pinguis) remain one of the most critically endangered reptiles in the world. Factors contributing to that status include habitat loss, predation by introduced species, and competition with introduced herbivores. On Guana Island, British Virgin Islands, the presence of feral sheep (Ovis aries) has been a hypothesized detriment to iguanas. Using motion sensitive cameras, we documented the distribution of feral sheep on Guana Island in 2010. We also quantified the impact of feral sheep on ground vegetation by comparing plant abundance at long term sheep exclosures and areas where sheep were absent to areas where sheep were present. Finally, we compared sheep distribution to iguana distribution on the island. The co-occurrence of sheep and Stout Iguanas was less than expected, indicating possible competition. Although we detected no difference in vegetative cover between areas where sheep were present and absent, the long-term exclosures showed that the exclusion of sheep allowed the abundance of many plant species to increase. Our data support the hypothesis that feral sheep are altering the abundance of ground-level vegetation and limiting iguana distribution on the island.&#x0D; &#x0D; &#x0D; &#x0D;

Differential response of nest predators to the presence of a decoy parent in artificial nests

Capsule Mammalian and avian predators respond differently to decoys. Aims To investigate if parental attendance, which is often not accounted for in artificial nest studies, could alter predator guilds and predation rates. Methods To analyze the effects of simulated parental attendance on nest predation trends we implemented decoys of mounted American Robin Turdus migratorius specimens. We set up 22 nest-sites in an Illinois (USA) forest with control (no decoy) and experimental (with decoy) nests, the latter of which simulated parental attendance. Motion-sensitive cameras and bite-mark impressions on plasticine eggs and quail eggs identified predators. Results We found that simulated parental attendance significantly reduced nest predation rates: 61% of the 22 paired treatments were totally depredated, and more control nests (77.3%) were depredated in comparison with nests with decoys (9.1%). Mammalian predators predominantly attacked nests with decoys and avian predators predominantly attacked control nests. Conclusions Using taxidermic decoys in artificial nest experiments may improve the emulation of predation trends of natural nests, while revealing that parental attendance differentially affects predators.