Giant Anteater Myrmecophaga Tridactyla Research Articles

Prioritizing road mitigation using ecologically based land‐use planning

AbstractWildlife–vehicle collisions (WVCs) are a critical threat to biodiversity and human safety. To implement WVC mitigation measures where most needed, we need to link models predicting the probability of the presence of species, at large spatial scales, with the likelihood of occurring collisions along roads. Here, we propose a framework for the prioritization of road sections for implementing mitigation measures using ecologically based information. Within this framework, we first model the likelihood of WVC occurrence for focal species in road vicinity areas. We then use spatial prioritization tools to select road sections that entail a higher probability of WVC across the focal species using user‐defined criteria for weighting species records. We applied this framework to Mato Grosso do Sul state (Brazil), using systematic information on WVC collected over 3 years along ca. 2000 km of roads. We focused on the WVC involving three large mammals commonly road‐killed therein, which represent a threat to humans when involved in WVC: the lowland tapir Tapirus terrestris, giant anteater Myrmecophaga tridactyla and capybara Hydrochoerus hydrochaeris. We were able to identify road sections (<10% of the road network) that should be prioritized for implementing mitigation actions, which could significantly reduce the number of WVCs. However, the large extent of the road network classified as a priority for mitigation suggests the need to engage the public and private sectors in the early stages of the decision‐making process, in order to reach a consensus on the prioritization. Our framework may improve the environmental licensing process, namely by guiding where mitigation measures should be implemented first.

A conservation landscape for the Dry Chaco based on species habitat suitability

The Dry Chaco (DCH) is a biodiversity-rich region that contains the largest dry forest in the world. It is seriously endangered and has one of the fastest deforestation rates. Yet, very few conservation efforts have been undertaken to protect this ecosystem, and information to develop efficient and sustainable land-use plans is scarce. This study aimed to design a conservation landscape that would maximize the conservation of the DCH’s ecological integrity, endangered species, and ecological and evolutionary processes. Five focal species of high conservation value were chosen based on their ecological roles, conservation status, or endemism: white-lipped peccary Tayassu pecari, chacoan peccary Catagonus wagneri, giant anteater Myrmecophaga tridactyla, tapir Tapirus terrestris, and giant armadillo Priodontes maximus. We used interviews with local informants to obtain information on species presence and location. Their habitat suitability was modelled and ranked using Maxent software. A conservation landscape was designed by overlapping these spatially explicit models. A systematic conservation planning framework was followed, considering habitat connectivity using Zonation. Interviews proved to be useful for conservation planning in this region with longstanding close ethnozoological relationships. The spatial design obtained was compared with existing land-use policies and protected areas to discuss conservation strategies that could be efficient if applied in the DCH and considering land sharing vs. land sparing conservation strategies. There is a large surface of suitable habitat for the studied species, but their conservation cannot be ensured with the present conservation schemes. We consider land-sharing as a feasible conservation strategy for this region and its species, and identified areas that should be preserved and their optimal connections to increase conservation opportunities for the Dry Chaco.

Dieta de Myrmecophaga tridactyla (Pilosa: Myrmecophagidae) en pastizales y bosques del noreste de Santiago del Estero y su relación con las hormigas

The giant anteater Myrmecophaga tridactyla is in a vulnerable state of conservation due to alterations occurred in its habitat. Knowing its food sources, namely the ant species which are the most abundant component of its diet in the Chaco semiarid areas will help generate strategies for its conservation. This study aimed to prove the presence of the M. tridactyla in the north-west part of Santiago del Estero, determine food offer of ant in grassland and forest environments in addition to identify composition and abundance of the ants making up its diet. To attest the presence of the giant anteater, 22.4 km of transects were traversed in both environments by collecting evidences and feces. To determine ant rich- ness and abundance, samplings were done using pitfall tramps. Feces analysis showed that the diet comprised ten ant genres that equals 50% of the formicide richness in the area under study. From the total of the ants identified in feces, 95% belonged to Ectatomma sp. and Camponotus sp. According to the values of richness, abundance and similarity obtained, the ant offer for the M. tridactyla ?s diet is similar in both environments. All the above suggests that both the forest and the grasslands in the northest of Santiago del Estero are propitious for conserving the species. In general, the importance of these two environments should be considered by the policies protecting the conservation of the specie in this area.

Prey Preferences of the Jaguar Panthera onca Reflect the Post-Pleistocene Demise of Large Prey

Documenting the impacts of the Pleistocene megafaunal extinctions on predator-prey interactions is a challenge because of the incomplete fossil record and depauperate extant community structure. We used a comparative ecological approach to investigate whether the existing prey preference patterns of jaguars Panthera onca were potentially affected by the Pleistocene extinctions in the Americas compared with large felids in Africa and Asia. We reviewed the literature and found 25 studies reporting 3214 jaguar kills recorded throughout the species’ distribution. We found that jaguars significantly preferred capybara Hydrochaeris hydrochaeris and giant anteater Myrmecophaga tridactyla, and avoided agoutis, carnivorans, primates, black-eared opossum Didelphis marsupialis and tapirs. Generalised linear models showed that jaguars select prey primarily based on socio-ecological and behavioural traits (abundance and herd size), rather than morphological characteristics (body size). Nonetheless, their accessible prey weight range was 6-60 kg, preferred prey weight range was 45-85 kg, and mean mass of significantly preferred prey was 32 ± 13 kg leading to a predator to prey body mass ratio of 1:0.53, which is much less than that of other solitary felids. Compared with other large, solitary felids, jaguars have an unusual predator to prey body mass ratio, show limited effect of prey morphology as a driver of prey selection, lack evidence of optimal foraging beyond their preferred prey, and an absence of preferentially hunting on Cetartiodactyla herbivores. These features, coupled with the reduction in jaguar body mass since the Pleistocene, suggest that the loss of larger potential prey items within the preferred and accessible weight ranges at the end-Pleistocene still affects jaguar predatory behaviour. It may be that jaguars survived this mass extinction event by preferentially preying on relatively small species.

Determination of the karyotype of the giant anteater Myrmecophaga tridactyla (Myrmecophagidae: Xenarthra) using classical and molecular cytogenetic techniques

The karyotype of the giant anteater Myrmecophaga tridactyla was studied throughout the species’ Argentine range. Images of the chromosome complement clearly revealed the karyotype and identified previously misinterpreted chromosomes. The peripheral blood lymphocytes of 26 adult animals (11 males and 15 females) were cultured and used to obtain mitotic metaphases. These preparations were subjected to conventional staining, G- and C-banding, and Fluorescent in situ Hibridization (FISH). Spermatocyte pachytene microspreads for one adult were examined for synaptonemal complexes. The karyotype (2n = 60 XX/XY; Fundamental Number (FN) = 110 without XY) showed an autosomal complement of six metacentric, 18 submetacentric, and six acrocentric chromosome pairs. The X chromosome (4.67 ± 0.29% of the haploid set) was shown to be large and submetacentric, similar in size to autosomes 3–5. The Y chromosome was submetacentric (2.60 ± 1.08% of the haploid set). It is, however, larger than the Y chromosome of the closely related armadillos. Pairs 1, 3, 4, 5, 6, 9, 11, 14, 15, 23, 25 and 29 showed small masses of heterochromatin in the pericentromeric region. These masses were slightly larger in chromosome pairs 8, 10 and 18. Pairs 2, 7, 16, 17, 19, 20, 21, 22, 24, 26, 27 and 28 were entirely C-negative. Analysis of the telomeric sequences by FISH involving a Cy3-conjugated peptide nucleic acid pantelomeric probe revealed no signals from the interstitial regions. Ag-NORs were located on chromosomes 5, 10, 11, 21 and 23. The spermatocyte pachytene microspreads confirmed the morphology and size of both sex chromosomes. The present results, obtained via the analysis of a large number of specimens, provide an in-depth characterization of the chromosomal complement of this species.

Registros de Hormigas Y Termitas Presentes en la Dieta de Osos Hormigueros (Mammalia: Myrmecophagidae) en Tres Localidades de Colombia

Anteaters (Mammalia: Myrmecophagidae) feed mainly on ants and termites. Three anteater species are present in Colombia: the giant anteater Myrmecophaga tridactyla, the Northern lesser anteater Tamandua mexicana, and the Southern lesser anteater Tamandua tetradactyla. Nothing is known about their trophic ecology in the country. This study presents records of prey consumed by these species based on the analysis of stomach contents and feces, and compares the interspecific differences in consumed prey types. Data for M. tridactyla were obtained from four fecal samples from the Orinoco region, and the Tamandua samples were obtained from stomach contents of two specimens, one from the Andes region and the second one from the Orinoco region. Twenty-seven ant species were identified, belonging to 14 genera, ten tribes, and five subfamilies. Only two species of termites were found. Tamandua mexicana was the anteater that ate the greatest amount of ant species. Camponotus, Solenopsis and Ectatomma were the most frequent ant genera, and workers were more common than other castes. Tamandua species fed mainly on arboreal ants, while M. tridactyla had only ingested terrestrial ants. The differences between diets of anteaters seem to be related with resource availability and the abundance of ants in the habitat of each species.

Evidence of high inbreeding in a population of the endangered giant anteater, Myrmecophaga tridactyla (Myrmecophagidae), from Emas National Park, Brazil

We report the genetic structure, relatedness and mating structure of a population of the endangered giant anteater Myrmecophaga tridactyla Linnaeus, 1758 in the Emas National Park, Brazil, based on variability at five microsatellite loci. Additionally, we addressed the hypothesis that the M. tridactyla population studied has low levels of polymorphism and high levels of inbreeding and relatedness and that animals with overlapping home range are highly related. All five microsatellite loci displayed low levels of polymorphism and of expected and observed heterozygosity. The low level of polymorphism and high inbreeding showed by the population studied may be the outcome of high mortality and reduction in population size due to recurrent fire events in the Emas National Park, as reported in 1994. The reduction in population size may have led to a higher frequency of mating between closely related animals, augmented by the isolation of the population in the park because of the expansion of agricultural land and fragmentation of the Cerrado environment. The natural history of M. tridactyla and the phylopatric (sex-biased dispersal) behavior of females should increase the effects of isolation and bottlenecking, decreasing gene flow and increasing inbreeding. However, the low levels of polymorphism found in this population may simply be due to the natural history and evolution of M. tridactyla as reported for other species. The genetic structure and dynamics of this population needs to be investigated more profoundly in order to provide sound data for the design of conservation strategies for M. tridactyla in the Emas National Park.