An empirical evaluation of camera trap study design: How many, how long and when?

Abstract Camera traps deployed in grids or stratified random designs are a well‐established survey tool for wildlife but there has been little evaluation of study design parameters. We used an empirical subsampling approach involving 2,225 camera deployments run at 41 study areas around the world to evaluate three aspects of camera trap study design (number of sites, duration and season of sampling) and their influence on the estimation of three ecological metrics (species richness, occupancy and detection rate) for mammals. We found that 25–35 camera sites were needed for precise estimates of species richness, depending on scale of the study. The precision of species‐level estimates of occupancy (ψ) was highly sensitive to occupancy level, with 0.75) species, but more than 150 camera sites likely needed for rare (ψ < 0.25) species. Species detection rates were more difficult to estimate precisely at the grid level due to spatial heterogeneity, presumably driven by unaccounted habitat variability factors within the study area. Running a camera at a site for 2 weeks was most efficient for detecting new species, but 3–4 weeks were needed for precise estimates of local detection rate, with no gains in precision observed after 1 month. Metrics for all mammal communities were sensitive to seasonality, with 37%–50% of the species at the sites we examined fluctuating significantly in their occupancy or detection rates over the year. This effect was more pronounced in temperate sites, where seasonally sensitive species varied in relative abundance by an average factor of 4–5, and some species were completely absent in one season due to hibernation or migration. We recommend the following guidelines to efficiently obtain precise estimates of species richness, occupancy and detection rates with camera trap arrays: run each camera for 3–5 weeks across 40–60 sites per array. We recommend comparisons of detection rates be model based and include local covariates to help account for small‐scale variation. Furthermore, comparisons across study areas or times must account for seasonality, which could have strong impacts on mammal communities in both tropical and temperate sites

SNAPSHOT USA 2019 : a coordinated national camera trap survey of the United States

This article is protected by copyright. All rights reserved.With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August - 24 November of 2019). We sampled wildlife at 1509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian's eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the USA. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban-wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot-usa, as well as future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species-specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication.Publisher PDFPeer reviewe

Conformational Dependence and Conservation of an Immunodominant Epitope within the Babesia equi Erythrocyte-Stage Surface Protein Equi Merozoite Antigen 1

Equi merozoite antigen 1 (EMA-1) is an immunodominant Babesia equi erythrocyte-stage surface protein. A competitive enzyme-linked immunosorbent assay (ELISA), based on inhibition of monoclonal antibody (MAb) 36/133.97 binding to recombinant EMA-1 by equine anti- B. equi antibodies, detects horses infected with strains present throughout the world. The objectives of this study were to define the epitope bound by MAb 36/133.97 and quantify the amino acid conservation of EMA-1, including the region containing the epitope bound by MAb 36/133.97. The alignment of the deduced amino acid sequence of full-length EMA-1 (Florida isolate) with 15 EMA-1 sequences from geographically distinct isolates showed 82.8 to 99.6% identities (median, 98.5%) and 90.5 to 99.6% similarities (median, 98.9%) between sequences. Full-length and truncated recombinant EMA-1 proteins were expressed and tested for their reactivities with MAb 36/133.97. Binding required the presence of amino acids on both N- and C-terminal regions of a truncated peptide (EMA-1.2) containing amino acids 1 to 98 of EMA-1. This result indicated that the epitope defined by MAb 36/133.97 is dependent on conformation. Sera from persistently infected horses inhibited the binding of MAb 36/133.97 to EMA-1.2 in a competitive ELISA, indicating that equine antibodies which inhibit binding of MAb 36/133.97 also recognize epitopes in the same region (the first 98 residues). Within this region, the deduced amino acid sequences had 85.7 to 100% identities (median, 99.0%), with similarities of 94.9 to 100% (median, 100%). Therefore, the region which binds to both MAb 36/133.97 and inhibiting equine antibodies has a median amino acid identity of 99.0% and a similarity of 100%. These data provide a molecular basis for the use of both EMA-1 and MAb 36/133.97 for the detection of antibodies against B. equi

Amphibians and reptiles of Wildsumaco Wildlife Sanctuary,&amp;nbsp;Napo Province, Ecuador

We conducted a long-term inventory of the herpetofauna of Wildsumaco Wildlife Sanctuary in the eastern part of the Napo Province in Ecuador. This private preserve is about 500 ha in size and is located on the southern slopes of Volc&amp;aacute;n Sumaco. The preserve contains primary forest, secondary forest, and pasture habitats. Based mostly on nocturnal transect sampling we documented 39 species of amphibians including one species of salamander, two species of caecilians, and 36 species of frogs. Rain frogs (Pristimantis Jiminez de la Espada, 1871) were diverse with 14 species documented. A diverse species assemblage of 45 reptile species was also documented on the preserve. Six amphibian species found were listed by the IUCN Red List. At least three species exhibited substantial geographic range extensions and seven species showed elevational range extensions. We discovered several undescribed species including one salamander, three frogs, one lizard, and one snake

Development of specific immunoglobulin Ga (IgGa) and IgGb antibodies correlates with control of parasitemia in Babesia equi Infection

In this study, the kinetics of specific immunoglobulin G (IgG) isotypes were characterized in Babesia equi (Theileria equi)-infected horses. IgGa and IgGb developed during acute infection, whereas IgG(T) was detected only after resolution of acute parasitemia. The same IgG isotype profile induced during acute infection was obtained by equi merozoite antigen 1/saponin immunization

Towards understanding the liver fluke transmission dynamics on farms: detection of liver fluke transmitting snail and liver fluke-specific environmental DNA in water samples from an irrigated dairy farm in Southeast Australia

Livestock production around the world is impacted by liver fluke (Fasciola spp.) infection resulting in serious economic losses to the beef, dairy and sheep industries with significant losses of about $90 million per annum in Australia. Triclabendazole (TCBZ) is the most effective anthelmintic treatment available to control liver fluke infections; however, the widespread emergence of TCBZ resistance in livestock threatens liver fluke control. Alternative control measures to lower exposure of livestock to liver fluke infection would help to preserve the usefulness of current anthelmintic treatments. Environmental DNA (eDNA) based identification of liver fluke and the intermediate snail host in the water bodies is a robust method to assess the risk of liver fluke infection on farms. In this study, we used a multiplex quantitative PCR assay of water samples to detect and quantify eDNA of Fasciola hepatica (F. hepatica) and Austropeplea tomentosa (A. tomentosa), a crucial intermediate snail host for liver fluke transmission in South-east Australia. Water samples were collected from an irrigation channel for a period of 7 months in 2016 (February, March, May, September, October, November and December) at a dairy farm located at Maffra, Victoria, South-east Australia. Using an effective eDNA extraction method, the multiplex qPCR assay allows for the independent but simultaneous detection of eDNA released from liver fluke life stages and snails using specific primers and a probe targeting the ITS-2 region of the liver fluke and snail, respectively, with minimal inhibition from contaminants in field collected water samples. The sensitivity of this assay to detect eDNA of liver fluke and snails was observed to be 14 fg and 50 fg, respectively, in the presence of field collected water samples. Differential levels of liver fluke and snail specific eDNA in water were observed at the time points analysed in this study. The successful detection of eDNA specific to liver fluke and snails from the field collected water samples provides a precedent for the use of this method as a monitoring tool to determine the prevalence of liver fluke and liver fluke-transmitting snails in irrigation regions. Further, this method has the enormous potential to allow an assessment of the liver fluke transmission zones on farms and to inform the application of effective control strategies