Evaluating expert-based habitat suitability information of terrestrial mammals with GPS-tracking data

AIM

Macroecological studies that require habitat suitability data for many species often derive this information from expert opinion. However, expert-based information is inherently subjective and thus prone to errors. The increasing availability of GPS tracking data offers opportunities to evaluate and supplement expert-based information with detailed empirical evidence. Here, we compared expert-based habitat suitability information from the International Union for Conservation of Nature (IUCN) with habitat suitability information derived from GPS-tracking data of 1,498 individuals from 49 mammal species.

LOCATION

Worldwide.

TIME PERIOD

1998-2021.

MAJOR TAXA STUDIED

Forty-nine terrestrial mammal species.

METHODS

Using GPS data, we estimated two measures of habitat suitability for each individual animal: proportional habitat use (proportion of GPS locations within a habitat type), and selection ratio (habitat use relative to its availability). For each individual we then evaluated whether the GPS-based habitat suitability measures were in agreement with the IUCN data. To that end, we calculated the probability that the ranking of empirical habitat suitability measures was in agreement with IUCN's classification into suitable, marginal and unsuitable habitat types.

RESULTS

IUCN habitat suitability data were in accordance with the GPS data (> 95% probability of agreement) for 33 out of 49 species based on proportional habitat use estimates and for 25 out of 49 species based on selection ratios. In addition, 37 and 34 species had a > 50% probability of agreement based on proportional habitat use and selection ratios, respectively.

MAIN CONCLUSIONS

We show how GPS-tracking data can be used to evaluate IUCN habitat suitability data. Our findings indicate that for the majority of species included in this study, it is appropriate to use IUCN habitat suitability data in macroecological studies. Furthermore, we show that GPS-tracking data can be used to identify and prioritize species and habitat types for re-evaluation of IUCN habitat suitability data.

AMAZONIA CAMTRAP: A dataset of mammal, bird, and reptile species recorded with camera traps in the Amazon forest

The Amazon forest has the highest biodiversity on earth. However, information on Amazonian vertebrate diversity is still deficient and scattered across the published, peer-reviewed and grey literature and in unpublished raw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazon regions to compile the most extensive dataset of inventories of mammal, bird and reptile species ever assembled for the area. The complete dataset comprises 154,123 records of 317 species (185 birds, 119 mammals and 13 reptiles) gathered from surveys from the Amazonian portion of eight countries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru, Suriname and Venezuela). The most frequently recorded species per taxa were: mammals - Cuniculus paca (11,907 records); birds - Pauxi tuberosa (3,713 records); and reptiles - Tupinambis teguixin (716 records). The information detailed in this data paper opens-up opportunities for new ecological studies at different spatial and temporal scales, allowing for a more accurate evaluation of the effects of habitat loss, fragmentation, climate change and other human-mediated defaunation processes in one of the most important and threatened tropical environments in the world. The dataset is not copyright restricted; please cite this data-paper when using its data in publications and we also request that researchers and educators inform us of how they are using this data.

Occurrence of potential wild hosts of Echinococcus vogeli in the forests of southwestern Brazilian Amazonia

Abstract The helminth Echinococcus vogeliRausch & Bernstein, 1972 is a causative agent of Neotropical Echinococcosis, a chronic zoonotic disease which is endemic to the Neotropical region. This parasite is transmitted from bush dogs (Speothos venaticus) to their prey, which include lowland pacas (Cuniculus paca) and agoutis (Dasyprocta spp.). In Brazil, most human cases of Neotropical Echinococcosis have been recorded in the Amazonian states of Acre and Pará, although few data are available on the occurrence of the potential definitive or intermediate hosts of E. vogeli in the Amazon region. In the present study, we surveyed the forests surrounding 46 human communities located within and around of outside six sustainable-use protected areas in the southwestern Amazon basin of Brazil. The forests were surveyed using camera traps to determine the local presence of potential wild hosts of E. vogeli, and the exploitation of these hosts for game meat was evaluated through interviews with 136 subsistence hunters resident in the local communities. We recorded pacas, agoutis, and bush dogs, as well as domestic dogs (Canis familiaris), all potential reservoirs of Neotropical Echinococcosis, using the same habitats. We also confirmed the frequent consumption of paca and agouti meat by subsistence hunters and their families in the study communities. Our data contribute to the understanding of the occurrence of E. vogeli in Brazilian ecosystems.

Extensive aquatic subsidies lead to territorial breakdown and high density of an apex predator

Energetic subsidies between terrestrial and aquatic ecosystems can strongly influence food webs and population dynamics. Our objective was to study how aquatic subsidies affected jaguar (Panthera onca) diet, sociality, and population density in a seasonally flooded protected area in the Brazilian Pantanal. The diet (n = 138 scats) was dominated by fish (46%) and aquatic reptiles (55%), representing the first jaguar population known to feed extensively on fish and to minimally consume mammals (11%). These aquatic subsidies supported the highest jaguar population density estimate to date (12.4 jaguars/100 km²) derived from camera traps (8,065 trap nights) and GPS collars (n = 13). Contrary to their mostly solitary behavior elsewhere, we documented social interactions previously unobserved between same-sex adults including cooperative fishing, co-traveling, and play. Our study demonstrates that aquatic subsidies, frequently described in omnivores, can also transform the ecology and behavior of obligate carnivores.

Environmental and anthropogenic factors synergistically affect space use of jaguars

Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and function.^1-4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations.⁵ Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range.^6-8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars' spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores.

Effects of body size on estimation of mammalian area requirements

Accurately quantifying species' area requirements is a prerequisite for effective area-based conservation. This typically involves collecting tracking data on species of interest and then conducting home-range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home-range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross-validation to quantify bias in empirical home-range estimates. Area requirements of mammals <10 kg were underestimated by a mean approximately15%, and species weighing approximately100 kg were underestimated by approximately50% on average. Thus, we found area estimation was subject to autocorrelation-induced bias that was worse for large species. Combined with the fact that extinction risk increases as body mass increases, the allometric scaling of bias we observed suggests the most threatened species are also likely to be those with the least accurate home-range estimates. As a correction, we tested whether data thinning or autocorrelation-informed home-range estimation minimized the scaling effect of autocorrelation on area estimates. Data thinning required an approximately93% data loss to achieve statistical independence with 95% confidence and was, therefore, not a viable solution. In contrast, autocorrelation-informed home-range estimation resulted in consistently accurate estimates irrespective of mass. When relating body mass to home range size, we detected that correcting for autocorrelation resulted in a scaling exponent significantly >1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum.

Moving in the Anthropocene: Global reductions in terrestrial mammalian movements

Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission.

Genome-wide signatures of complex introgression and adaptive evolution in the big cats

The great cats of the genus Panthera comprise a recent radiation whose evolutionary history is poorly understood. Their rapid diversification poses challenges to resolving their phylogeny while offering opportunities to investigate the historical dynamics of adaptive divergence. We report the sequence, de novo assembly, and annotation of the jaguar (Panthera onca) genome, a novel genome sequence for the leopard (Panthera pardus), and comparative analyses encompassing all living Panthera species. Demographic reconstructions indicated that all of these species have experienced variable episodes of population decline during the Pleistocene, ultimately leading to small effective sizes in present-day genomes. We observed pervasive genealogical discordance across Panthera genomes, caused by both incomplete lineage sorting and complex patterns of historical interspecific hybridization. We identified multiple signatures of species-specific positive selection, affecting genes involved in craniofacial and limb development, protein metabolism, hypoxia, reproduction, pigmentation, and sensory perception. There was remarkable concordance in pathways enriched in genomic segments implicated in interspecies introgression and in positive selection, suggesting that these processes were connected. We tested this hypothesis by developing exome capture probes targeting ~19,000 Panthera genes and applying them to 30 wild-caught jaguars. We found at least two genes (DOCK3 and COL4A5, both related to optic nerve development) bearing significant signatures of interspecies introgression and within-species positive selection. These findings indicate that post-speciation admixture has contributed genetic material that facilitated the adaptive evolution of big cat lineages.

Space Use and Movement of a Neotropical Top Predator: The Endangered Jaguar

Accurately estimating home range and understanding movement behavior can provide important information on ecological processes. Advances in data collection and analysis have improved our ability to estimate home range and movement parameters, both of which have the potential to impact species conservation. Fitting continuous-time movement model to data and incorporating the autocorrelated kernel density estimator (AKDE), we investigated range residency of forty-four jaguars fit with GPS collars across five biomes in Brazil and Argentina. We assessed home range and movement parameters of range resident animals and compared AKDE estimates with kernel density estimates (KDE). We accounted for differential space use and movement among individuals, sex, region, and habitat quality. Thirty-three (80%) of collared jaguars were range resident. Home range estimates using AKDE were 1.02 to 4.80 times larger than KDE estimates that did not consider autocorrelation. Males exhibited larger home ranges, more directional movement paths, and a trend towards larger distances traveled per day. Jaguars with the largest home ranges occupied the Atlantic Forest, a biome with high levels of deforestation and high human population density. Our results fill a gap in the knowledge of the species' ecology with an aim towards better conservation of this endangered/critically endangered carnivore-the top predator in the Neotropics.

A biodiversity hotspot losing its top predator: The challenge of jaguar conservation in the Atlantic Forest of South America

The jaguar is the top predator of the Atlantic Forest (AF), which is a highly threatened biodiversity hotspot that occurs in Brazil, Paraguay and Argentina. By combining data sets from 14 research groups across the region, we determine the population status of the jaguar and propose a spatial prioritization for conservation actions. About 85% of the jaguar's habitat in the AF has been lost and only 7% remains in good condition. Jaguars persist in around 2.8% of the region, and live in very low densities in most of the areas. The population of jaguars in the AF is probably lower than 300 individuals scattered in small sub-populations. We identified seven Jaguar Conservation Units (JCUs) and seven potential JCUs, and only three of these areas may have ≥50 individuals. A connectivity analysis shows that most of the JCUs are isolated. Habitat loss and fragmentation were the major causes for jaguar decline, but human induced mortality is the main threat for the remaining population. We classified areas according to their contribution to jaguar conservation and we recommend management actions for each of them. The methodology in this study could be used for conservation planning of other carnivore species.

Adrenal activity in maned wolves is higher on farmlands and park boundaries than within protected areas

In this study we measured excreted fecal corticoid metabolites (FCM) in maned wolves (Chrysocyon brachyurus) living within a protected reserve, on farmlands or in a boundary zone between the two habitats, and determined the impacts of season and reproductive status on adrenal activity. Feces were collected within a national park (n=191 samples), a park boundary zone (n=39) and on nearby farmlands (n=27), processed and analyzed by enzyme immunoassay. FCM amounts from samples collected on farmlands were higher (P<0.05) than in those collected inside the reserve and from the boundary zone. In relation to seasonality, FCM were elevated (P<0.05) in spring (September-November) when wolf pairs were raising young. We then divided the samples collected during breeding season (March-August) into cycling females and male/non-cycling females based on fecal progesterone: fecal testosterone ratio. FCM concentrations of the former collected inside the park were higher than (P<0.05) than the latter group. However, there were no differences in FCM levels between the two groups for samples collected in the boundary zone and on farmlands. Furthermore, FCM concentrations of male/non-cycling females samples collected on farmlands were 2- to 5-fold higher (P<0.05) than in counterparts collected inside the park. The consistently high FCM concentrations in samples collected on farmlands indicate that, in addition to seasonality, gender and reproductive status, anthropogenic pressures also contribute to elevating adrenal steroid for individuals living in altered habitat.

Noninvasive monitoring of adrenocortical function in captive jaguars (Panthera onca)

Jaguars are threatened with extinction throughout their range. A sustainable captive population can serve as a hedge against extinction, but only if they are healthy and reproduce. Understanding how jaguars respond to stressors may help improve the captive environment and enhance their wellbeing. Thus, our objectives were to: (1) conduct an adrenocorticotrophic hormone (ACTH) challenge to validate a cortisol radioimmunoassay (RIA) for noninvasive monitoring of adrenocortical function in jaguars; (2) investigate the relationship between fecal corticoid (FCM) and androgen metabolite (FAM) concentrations in males during the ACTH challenge; and (3) establish a range of physiological concentrations of FCMs for the proposed protocol. Seven jaguars (3 M, 4 F) received 500 IU/animal of ACTH. Pre- and post-ACTH fecal samples were assayed for corticoid (M and F) and androgen metabolites (M) by RIA. Concentrations of FCMs increased (P80.01) after ACTH injection (pre-ACTH: 0.90 ± 0.12 µg/g dry feces; post-ACTH: 2.55 ± 0.25 µg/g). Considering pre- and post-ACTH samples, FCM concentrations were higher (P80.01) in males (2.15 ± 0.20 µg/g) than in females (1.30 ± 0.20 µg/g), but the magnitude of the response to ACTH was comparable (P>0.05) between genders. After ACTH injection, FAMs increased in two (of 3) males; in one male, FCMs and FAMs were positively correlated (0.60; P80.01). Excretion of FCMs was assessed in 16 jaguars (7 M, 9 F) and found to be highly variable (range, 80.11-1.56 µg/g). In conclusion, this study presents a cortisol RIA for monitoring adrenocortical function in jaguars noninvasively.

The effect of habitat fragmentation on the genetic structure of a top predator: loss of diversity and high differentiation among remnant populations of Atlantic Forest jaguars (Panthera onca)

Habitat fragmentation may disrupt original patterns of gene flow and lead to drift-induced differentiation among local population units. Top predators such as the jaguar may be particularly susceptible to this effect, given their low population densities, leading to small effective sizes in local fragments. On the other hand, the jaguar's high dispersal capabilities and relatively long generation time might counteract this process, slowing the effect of drift on local populations over the time frame of decades or centuries. In this study, we have addressed this issue by investigating the genetic structure of jaguars in a recently fragmented Atlantic Forest region, aiming to test whether loss of diversity and differentiation among local populations are detectable, and whether they can be attributed to the recent effect of drift. We used 13 microsatellite loci to characterize the genetic diversity present in four remnant populations, and observed marked differentiation among them, with evidence of recent allelic loss in local areas. Although some migrant and admixed individuals were identified, our results indicate that recent large-scale habitat removal and fragmentation among these areas has been sufficiently strong to promote differentiation induced by drift and loss of alleles at each site. Low estimated effective sizes supported the inference that genetic drift could have caused this effect within a short time frame. These results indicate that jaguars' ability to effectively disperse across the human-dominated landscapes that separate the fragments is currently very limited, and that each fragment contains a small, isolated population that is already suffering from the effects of genetic drift.

Development and testing of an optimized method for DNA-based identification of jaguar (Panthera onca) and puma (Puma concolor) faecal samples for use in ecological and genetic studies

The elusive nature and endangered status of most carnivore species imply that efficient approaches for their non-invasive sampling are required to allow for genetic and ecological studies. Faecal samples are a major potential source of information, and reliable approaches are needed to foster their application in this field, particularly in areas where few studies have been conducted. A major obstacle to the reliable use of faecal samples is their uncertain species-level identification in the field, an issue that can be addressed with DNA-based assays. In this study we describe a sequence-based approach that efficiently distinguishes jaguar versus puma scats, and that presents several desirable properties: (1) considerably high amplification and sequencing rates; (2) multiple diagnostic sites reliably differentiating the two focal species; (3) high information content that allows for future application in other carnivores; (4) no evidence of amplification of prey DNA; and (5) no evidence of amplification of a nuclear mitochondrial DNA insertion known to occur in the jaguar. We demonstrate the reliability and usefulness of this approach by evaluating 55 field-collected samples from four locations in the highly fragmented Atlantic Forest biome of Brazil and Argentina, and document the presence of one or both of these endangered felids in each of these areas.

Comparison of serum hormone levels of captive and free-living maned wolves Chrysocyon brachyurus

Serum hormone levels were compared between captive and free-living maned wolves and seasonal variations of sex hormones were studied. Blood samples were collected from 16 male and 26 female adult animals from Brazilian zoos, and from 30 male and 24 female free-living adults to determine serum progesterone and testosterone by radioimmunoassay. Serum testosterone concentrations varied (P < 0.05) across seasons for 16 captive males, being higher in autumn (2184.7 +/- 355.1 pg/mL) than in summer (1080.7 +/- 205.4 pg/mL), winter (1270.1 +/- 276.6 pg/mL) and spring (963.9 +/- 248.1 pg/mL), although they did not differ between summer, winter and spring. Testosterone concentration of 30 free-living males differed (P < 0.05) between autumn (824.1 +/- 512.2 pg/mL), winter (14.4 +/- 8.0 pg/mL) and spring (151.9 +/- 90.5 pg/mL). Comparison between captive and free-living animals showed no difference in autumn (P > 0.05). Sixteen captive males showed higher testosterone concentration during winter and spring compared with 30 free-living animals (P < 0.05). Progesterone concentration varied among seasons in 26 captive females (P < 0.05), being higher in autumn (15.3 +/- 3.1 ng/mL) than in summer (6.6 +/- 1.5 ng/mL), winter (5.3 +/- 3.1 ng/mL) and spring (4.3 +/- 0.7 ng/mL). Progesterone concentration of 24 free-living females varied between autumn (17.1 +/- 6.0 ng/mL) and winter (1.7 +/- 0.3 ng/mL) (P < 0.05), but we could not obtain data for spring or summer. No difference in progesterone levels was observed between captive and free-living females in autumn and winter.

Duration of spermatogenesis and daily sperm production in the jaguar (Panthera onca)

The jaguar, like most wild felids, is an endangered species. Since there are few data regarding reproductive biology for this species, our main goal was to investigate basic aspects of the testis and spermatogenesis. Four adult male jaguars were utilized; to determine the duration of spermatogenesis, two animals received an intratesticular injection of H(3)-thymidine. Mean (+/-SEM) testis weight and the gonadosomatic index were 17.7+/-2.2g and 0.05+/-0.01%, respectively, whereas the seminiferous tubules and the Leydig cells volume density were 74.7+/-3.8 and 16.7+/-1.6%. Eight stages of spermatogenesis were characterized, according to the tubular morphology system and acrosome development. Each spermatogenic cycle and the entire spermatogenic process (based on 4.5 cycles) lasted approximately 12.8+/-0.01 and 57.7+/-0.07 d. The number of Sertoli and Leydig cells per gram of testis was 29+/-4 x 10(6) and 107+/-12 x 10(6). Based on the number of round spermatids per pachytene spermatocyte (2.8+/-0.3:1; meiotic index); significant cell loss (30%) occurred during the two meiotic divisions. There were approximately eight spermatids for each Sertoli cell (Sertoli cell efficiency), whereas the daily sperm production per gram of testis was 16.9+/-1.2 x 10(6). We expect that in the near future, the knowledge obtained in the present investigation will facilitate, utilizing germ cell transplantation, preservation of the germinal epithelium and the ability to generate sperm from jaguars in testes of domestic cats.

Characterization of Rabies virus isolated from canids and identification of the main wild canid host in Northeastern Brazil

The rabies cases in dogs and wild canids in Northeastern Brazil are a public and animal health problem. This paper describes the identities of the coding region of the N-gene of Rabies virus (RABV) isolated in canids from Northeastern Brazil. The genetic tree generated using the sequence data described here divided the cluster BRAZILAN CANIDS into two subclusters (DOG-RELATED STRAINS and WILD CANID-RELATED STRAINS) with identities greater than those already described. The two subclusters are sub-divided into geographic groups related to the origin of the isolates, suggesting a long-standing ecological coexistence of the sequence types characteristic of the groups. This article also analyzes the 513-nucleotide stretch of the mitochondrial DNA control region of rabies-positive canids from Northeastern Brazil with a view to identifying the main RABV host among them. Among the four species of wild canids found in the region, two (Cerdocyon thous and Pseudalopex vetulus) are frequently associated with rabies. Phylogenetic analysis of sequence data generated from mtDNA suggests that C. thous is the main wild canid host in the region. The results obtained in this study are in concordance with the zoology and ecology of wild canids, and thus, help improve epidemiologic vigilance of rabies and allow a more targeted control of the disease.

Ticks (Acari: Ixodida) on wild carnivores in Brazil

The present study reports field data of ticks infesting wild carnivores captured from July 1998 to September 2004 in Brazil. Additional data were obtained from one tick collection and from previous published data of ticks on carnivores in Brazil. During field work, a total of 3437 ticks were collected from 89 Cerdocyon thous (crab-eating fox), 58 Chrysocyon brachyurus (maned wolf), 30 Puma concolor (puma), 26 Panthera onca (jaguar), 12 Procyon cancrivorus (crab-eating raccoon), 4 Speothos venaticus (bush dog), 6 Pseudalopex vetulus (hoary fox), 6 Nasua nasua (coati), 6 Leopardus pardalis (ocelot), 2 Leopardus tigrinus (oncilla), 1 Leopardus wiedii (margay), 1 Herpailurus yagouaroundi (jaguarundi), 1 Oncifelis colocolo (pampas cat), 1 Eira barbara (tayara), 1 Galictis vittata (grison), 1 Lontra longicaudis (neotropical otter), and 1 Potus flavus (kinkajou). Data obtained from the Acari Collection IBSP included a total of 381 tick specimens collected on 13 C. thous, 8 C. brachyurus, 3 P. concolor, 10 P. onca, 3 P. cancrivorus, 4 N. nasua, 1 L. pardalis, 1 L. wiedii, 4 H. yagouaroundi, 1 Galictis cuja (lesser grison), and 1 L. longicaudis. The only tick-infested carnivore species previously reported in Brazil, for which we do not present any field data are Pseudalopex gymnocercus (pampas fox), Conepatus chinga (Molina's hog-nosed skunk), and Conepatus semistriatus (striped hog-nosed skunk). We report the first tick records in Brazil on two Felidae species (O. colocolo, H. yagouaroundi), two Canidae species (P. vetulus, S. venaticus), one Procyonidae species (P. flavus) and one Mustelidae (E. barbara). Tick infestation remains unreported for 5 of the 26 Carnivora species native in Brazil: Oncifelis geoffroyi (Geoffroy's cat), Atelocynus microtis (short-eared dog), Pteronura brasiliensis (giant otter), Mustela africana (Amazon weasel), and Bassaricyon gabbii (olingo). Our field data comprise 16 tick species represented by the genera Amblyomma (12 species), Ixodes (1 species), Dermacentor (1 species), Rhipicephalus (1 species), and Boophilus (1 species). Additional 5 tick species (3 Amblyomma species and 1 species from each of the genera Ixodes and Ornithodoros) were reported in the literature. The most common ticks on Carnivora hosts were Amblyomma ovale (found on 14 host species), Amblyomma cajennense (10 species), Amblyomma aureolatum (10 species), Amblyomma tigrinum (7 species), Amblyomma parvum (7 species), and Boophilus microplus (7 species).

Changes in the fecal concentrations of cortisol and androgen metabolites in captive male jaguars (Panthera onca) in response to stress

In the present study we determined the efficacy of the measurement of fecal cortisol and androgen metabolite concentrations to monitor adrenal and testicular activity in the jaguar (Panthera onca). Three captive male jaguars were chemically restrained and electroejaculated once or twice within a period of two months. Fecal samples were collected daily for 5 days before and 5 days after the procedure and stored at -20 degrees C until extraction. Variations in the concentrations of cortisol and androgen metabolites before and after the procedure were determined by solid phase cortisol and testosterone radioimmunoassay and feces dry weight was determined by drying at 37 degrees C for 24 h under vacuum. On four occasions, fecal cortisol metabolite levels were elevated above baseline (307.8 +/- 17.5 ng/g dry feces) in the first fecal sample collected after the procedure (100 to 350% above baseline). On one occasion, we did not detect any variation. Mean (+/- SEM) fecal androgen concentration did not change after chemical restraint and electroejaculation (before: 131.1 +/- 26.7, after: 213.7 +/- 43.6 ng/g dry feces). These data show that determination of fecal cortisol and androgen metabolites can be very useful for a noninvasive assessment of animal well-being and as a complement to behavioral, physiological, and pathological studies. It can also be useful for the study of the relationship between adrenal activity and reproductive performance in the jaguar.

The potential for gamete recovery from non-domestic canids and felids

Species are becoming extinct at a rate 100 times the natural background rates. Considering all mammalian orders, 24% of all Carnivora species are threatened. The goal of carnivore conservation is to reverse the decline in populations and to secure remaining populations in ways that will assure enduring public support. In this context, biotechnology is a tool with tremendous potential for assisting the conservation of endangered canid and felid species. As the first step for biotechnology development is the gamete obtainment, this review will discuss the potential of gamete recovery from non-domestic canids and felids, based on learning how to apply these procedures in the domestic carnivores. Thus, electroejaculation and obtaining both epidydimal spermatozoon and spermatogonial germ cells are indicated as techniques for male gametes recovery. In the female gametes retrieval, different methods for oocyte recovery from both antral and preantral follicles, and the possibility for ovarian tissue transplantation are discussed. Furthermore, the study discusses the responsibilities involved in the use of assisted reproduction in endangered species conservation.

Comparative analyses of semen and endocrine characteristics of free-living versus captive jaguars (Panthera onca)

Semen and blood samples were obtained from free-living (n = 6) and captive (n = 8) jaguars (Panthera onca) to compare reproductive characteristics between the two populations. Semen samples were analysed for volume (ml), percentage of motile spermatozoa, rate of forward progression (0-5), concentration (10(6) ml(-1)), total sperm count (10(6)) and sperm morphology. Serum testosterone concentration was determined by radioimmunoassay. Although ejaculate volume was greater in captive jaguars (n = 47 samples) than in free-living jaguars (n = 7 samples) (P < 0.05), the free-living jaguars produced more total spermatozoa (59.3 +/- 12.8 versus 152.0 +/- 88.0 x 10(6), respectively; not significant) with better viability and forward progression (2.8 +/- 0.1 versus 3.5 +/- 0.2, respectively; P < 0.05) and more spermatozoa with normal morphology (73.5 +/- 3.9 versus 5.0 +/- 1.1%, respectively; P < 0.05). Serum testosterone concentrations were similar for captive and free-living male jaguars (3.1 +/- 0.7 and 2.1 +/- 0.8 ng ml(-1), respectively). In summary, the data showed that semen may be collected successfully from free-living jaguars and evaluated under field conditions to establish normative reproductive values in this species. The results also indicate that jaguars maintained in zoos show inferior seminal characteristics compared with free-living animals.