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1.
Bioscience ; 67(6): 534-545, 2017 Jun 01.
Article in English | MEDLINE | ID: mdl-28608869

ABSTRACT

We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature-a companion to the Paris Climate Deal-to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods.


Subject(s)
Biodiversity , Conservation of Natural Resources , Climate , Ecology , Ecosystem , Humans
2.
J Hered ; 106 Suppl 1: 459-68, 2015.
Article in English | MEDLINE | ID: mdl-26245781

ABSTRACT

The maned wolf (Chrysocyon brachyurus) is one of the largest South American canids, and conservation across this charismatic carnivore's large range is presently hampered by a lack of knowledge about possible natural subdivisions which could influence the population's viability. To elucidate the phylogeographic patterns and demographic history of the species, we used 2 mtDNA markers (D-loop and cytochrome b) from 87 individuals collected throughout their range, in Argentina, Bolivia, Brazil, and Uruguay. We found moderate levels of haplotype and nucleotide diversity, and the 14 D-loop haplotypes were closely related. Genetic structure results revealed 4 groups, and when coupled with model inferences from a coalescent analysis, suggested that maned wolves have undergone demographic fluctuations due to changes in climate and habitat during the Pleistocene glaciation period approximately 24000 years before present (YBP). This genetic signature points to an event that occurred within the timing estimated for the start of the contraction of the Cerrado around 50000 YBP. Our results reveal a genetic signature of population size expansion followed by contraction during Pleistocene interglaciations, which had similar impacts on other South American mammals. The 4 groups should for now be considered management units, within which future monitoring efforts should be conducted independently.


Subject(s)
Canidae/genetics , DNA, Mitochondrial/genetics , Genetic Variation , Genetics, Population , Animals , Animals, Wild/genetics , Argentina , Bolivia , Brazil , Conservation of Natural Resources , Evolution, Molecular , Gene Flow , Haplotypes , Likelihood Functions , Models, Genetic , Phylogeny , Phylogeography , Sequence Analysis, DNA , Uruguay
3.
PLoS One ; 6(12): e28939, 2011.
Article in English | MEDLINE | ID: mdl-22205984

ABSTRACT

Conserving animals beyond protected areas is critical because even the largest reserves may be too small to maintain viable populations for many wide-ranging species. Identification of landscape features that will promote persistence of a diverse array of species is a high priority, particularly, for protected areas that reside in regions of otherwise extensive habitat loss. This is the case for Emas National Park, a small but important protected area located in the Brazilian Cerrado, the world's most biologically diverse savanna. Emas Park is a large-mammal global conservation priority area but is too small to protect wide-ranging mammals for the long-term and conserving these populations will depend on the landscape surrounding the park. We employed novel, noninvasive methods to determine the relative importance of resources found within the park, as well as identify landscape features that promote persistence of wide-ranging mammals outside reserve borders. We used scat detection dogs to survey for five large mammals of conservation concern: giant armadillo (Priodontes maximus), giant anteater (Myrmecophaga tridactyla), maned wolf (Chrysocyon brachyurus), jaguar (Panthera onca), and puma (Puma concolor). We estimated resource selection probability functions for each species from 1,572 scat locations and 434 giant armadillo burrow locations. Results indicate that giant armadillos and jaguars are highly selective of natural habitats, which makes both species sensitive to landscape change from agricultural development. Due to the high amount of such development outside of the Emas Park boundary, the park provides rare resource conditions that are particularly important for these two species. We also reveal that both woodland and forest vegetation remnants enable use of the agricultural landscape as a whole for maned wolves, pumas, and giant anteaters. We identify those features and their landscape compositions that should be prioritized for conservation, arguing that a multi-faceted approach is required to protect these species.


Subject(s)
Behavior, Animal , Conservation of Natural Resources/statistics & numerical data , Ecosystem , Mammals , Tropical Climate , Animals , Brazil , Dogs
4.
Mol Ecol Resour ; 11(5): 862-71, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21676206

ABSTRACT

The use of scat surveys to obtain DNA has been well documented in temperate areas, where DNA preservation may be more effective than in tropical forests. Samples obtained in the tropics are often exposed to high humidity, warm temperatures, frequent rain and intense sunlight, all of which can rapidly degrade DNA. Despite these potential problems, we demonstrate successful mtDNA amplification and sequencing for faeces of carnivores collected in tropical conditions and quantify how sample condition and environmental variables influence the success of PCR amplification and species identification. Additionally, the feasibility of genotyping nuclear microsatellites from jaguar (Panthera onca) faeces was investigated. From October 2007 to December 2008, 93 faecal samples were collected in the southern Brazilian Amazon. A total of eight carnivore species was successfully identified from 71% of all samples obtained. Information theoretic analysis revealed that the number of PCR attempts before a successful sequence was an important negative predictor across all three responses (success of species identification, success of species identification from the first sequence and PCR amplification success), whereas the relative importance of the other three predictors (sample condition, season and distance from forest edge) varied between the three responses. Nuclear microsatellite amplification from jaguar faeces had lower success rates (15-44%) compared with those of the mtDNA marker. Our results show that DNA obtained from faecal samples works efficiently for carnivore species identification in the Amazon forest and also shows potential for nuclear DNA analysis, thus providing a valuable tool for genetic, ecological and conservation studies.


Subject(s)
Carnivora/genetics , DNA, Mitochondrial/isolation & purification , Feces/chemistry , Nucleic Acid Amplification Techniques/methods , Animals , Brazil , Cluster Analysis , DNA Primers/genetics , DNA, Mitochondrial/genetics , Genetic Markers/genetics , Microsatellite Repeats/genetics , Phylogeny , Sequence Analysis, DNA/methods , Species Specificity , Tropical Climate
5.
Conserv Biol ; 25(1): 154-62, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21029162

ABSTRACT

Most protected areas are too small to sustain populations of wide-ranging mammals; thus, identification and conservation of high-quality habitat for those animals outside parks is often a high priority, particularly for regions where extensive land conversion is occurring. This is the case in the vicinity of Emas National Park, a small protected area in the Brazilian Cerrado. Over the last 40 years the native vegetation surrounding the park has been converted to agriculture, but the region still supports virtually all of the animals native to the area. We determined the effectiveness of scat-detection dogs in detecting presence of five species of mammals threatened with extinction by habitat loss: maned wolf (Chrysocyon brachyurus), puma (Puma concolor), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), and giant armadillo (Priodontes maximus). The probability of scat detection varied among the five species and among survey quadrats of different size, but was consistent across team, season, and year. The probability of occurrence, determined from the presence of scat, in a randomly selected site within the study area ranged from 0.14 for jaguars, which occur primarily in the forested areas of the park, to 0.91 for maned wolves, the most widely distributed species in our study area. Most occurrences of giant armadillos in the park were in open grasslands, but in the agricultural matrix they tended to occur in riparian woodlands. At least one target species occurred in every survey quadrat, and giant armadillos, jaguars, and maned wolves were more likely to be present in quadrats located inside than outside the park. The effort required for detection of scats was highest for the two felids. We were able to detect the presence for each of five wide-ranging species inside and outside the park and to assign occurrence probabilities to specific survey sites. Thus, scat dogs provide an effective survey tool for rare species even when accurate detection likelihoods are required. We believe the way we used scat-detection dogs to determine the presence of species can be applied to the detection of other mammalian species in other ecosystems.


Subject(s)
Conservation of Natural Resources/methods , Endangered Species , Animals , Brazil , Canidae/physiology , Dogs , Feces , Female , Male , Panthera/physiology , Puma/physiology
6.
Gen Comp Endocrinol ; 168(1): 1-7, 2010 Aug 01.
Article in English | MEDLINE | ID: mdl-20412809

ABSTRACT

We developed and validated a non-invasive thyroid hormone measure in feces of a diverse array of birds and mammals. An I(131) radiolabel ingestion study in domestic dogs coupled with High Pressure Liquid Chromatography (HPLC) analysis, showed that peak excretion in feces occurred at 24-48h post-ingestion, with I(131)-labelled thyroid hormone metabolites excreted primarily as triiodothyronine (T3) and relatively little thyroxine (T4), at all excretion times examined. The immunoreactive T3 profile across these same HPLC fractions closely corresponded with the I(131) radioactive profile. By contrast, the T4 immunoreactive profile was disproportionately high, suggesting that T4 excretion included a high percentage of T4 stores. We optimized and validated T3 and T4 extraction and assay methods in feces of wild northern spotted owls, African elephants, howler monkeys, caribou, moose, wolf, maned wolf, killer whales and Steller sea lions. We explained 99% of the variance in high and low T3 concentrations derived from species-specific sample pools, after controlling for species and the various extraction methods tested. Fecal T3 reflected nutritional deficits in two male and three female howler monkeys held in captivity for translocation from a highly degraded habitat. Results suggest that thyroid hormone can be accurately and reliably measured in feces, providing important indices for environmental physiology across a diverse array of birds and mammals.


Subject(s)
Feces/chemistry , Radioimmunoassay/methods , Thyroid Hormones/analysis , Animals , Dogs , Elephants , Female , Haplorhini , Iodine Radioisotopes/analysis , Reindeer , Sea Lions , Strigiformes , Thyroxine/analysis , Triiodothyronine/analysis , Whale, Killer , Wolves
7.
J Zoo Wildl Med ; 40(2): 382-4, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19569492

ABSTRACT

The entodiniomorph ciliates (Ciliophora: Entodiniomorphida) are endosymbiotes widely found in the intestines of herbivorous mammals. These commensals commonly occur in the Artiodactyla and Perissodactyla and have also been described in the Proboscidea, Primates, Rodentia, and Diprotodontia. This study reports the first finding of a ciliate in a member of order Carnivora, the maned wolf (Chrysocyon brachyurus). Fecal samples from wild and captive maned wolves were screened using ethyl acetate sedimentation. Prevalence in fecal samples collected from free-ranging maned wolves in Brazil was 40% (6 of 15). Fecal samples from two of four captive individuals from the St. Louis Zoo also had the same species of ciliate. The largely frugivorous diet of the maned wolf likely explains the occurrence of these normally herbivore-associated endosymbiotes in a carnivore.


Subject(s)
Canidae/parasitology , Ciliophora Infections/veterinary , Ciliophora/isolation & purification , Animals , Animals, Wild/parasitology , Animals, Zoo/parasitology , Brazil/epidemiology , Ciliophora Infections/epidemiology , Feces/parasitology
8.
Science ; 295(5558): 1280-4, 2002 Feb 15.
Article in English | MEDLINE | ID: mdl-11847338

ABSTRACT

Coral reefs are the most biologically diverse of shallow water marine ecosystems but are being degraded worldwide by human activities and climate warming. Analyses of the geographic ranges of 3235 species of reef fish, corals, snails, and lobsters revealed that between 7.2% and 53.6% of each taxon have highly restricted ranges, rendering them vulnerable to extinction. Restricted-range species are clustered into centers of endemism, like those described for terrestrial taxa. The 10 richest centers of endemism cover 15.8% of the world's coral reefs (0.012% of the oceans) but include between 44.8 and 54.2% of the restricted-range species. Many occur in regions where reefs are being severely affected by people, potentially leading to numerous extinctions. Threatened centers of endemism are major biodiversity hotspots, and conservation efforts targeted toward them could help avert the loss of tropical reef biodiversity.


Subject(s)
Cnidaria , Conservation of Natural Resources , Ecosystem , Fishes , Nephropidae , Snails , Animals , Cnidaria/classification , Cnidaria/physiology , Fishes/classification , Fishes/physiology , Humans , Nephropidae/classification , Nephropidae/physiology , Seawater , Snails/classification , Snails/physiology , Tropical Climate
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