Giant Anteater Population Density Estimation and Viability Analysis Through Motion‐Sensitive Camera Records

Abstract

Giant anteater (Myrmecophaga tridactyla) populations are decreasing throughout their range. We tested a methodology for individual identification using camera records and fur patterns to estimate the giant anteater population in a protected area of the Brazilian Cerrado. We identified 9 adult individuals and successfully modeled population abundance and density. Our models estimated an adult population of 16.8 (range = 15–19) giant anteaters through a mark‐resight approach and 12.5 individuals (range = 9.7–25.5) through a spatially explicit capture‐recapture approach. Density estimates were 0.3–0.4 animals/km2. Using these estimates, we performed a population viability analysis to understand and predict this population's future. We modeled scenarios without direct effects and models simulating a double carrying capacity and the supplementation and removal of individuals. Even in the more optimistic scenarios, the population is predicted to decreases over time, with ≤8 individuals remaining in 100 years. Given the study area surroundings, realistic models include removals of giant anteaters in the population. Identification of giant anteaters using cameras can inspire conservationists to acquire population data throughout its distribution and obtain population trends to evaluate the species' conservation status. Individual identification of giant anteaters using a motion‐sensitive camera design is feasible, opens new avenues for population analyses, and allows the study of population trends in difficult regions. © 2021 The Wildlife Society.

The socio-spatial ecology of giant anteaters in the Brazilian Cerrado

“…Existing knowledge on giant anteater sociality is based on brief reports and are primarily from observations on captive animals (del Valle Jerez & Halloy, 2003; Bertassoni & Milléo Costa, 2010; Eyer & Miller, 2020), with only limited data on the behaviour of free-ranging animals (Montgomery & Lubin, 1975; Shaw et al ., 1987; Bertassoni & Milléo Costa, 2010; Bertassoni et al ., 2021; Giroux et al ., 2021). From these, giant anteaters are described as mostly solitary in the wild except during the mating season where courtship behaviour has been observed (Shaw et al ., 1987; Braga et al ., 2010; Bertassoni & Desbiez, 2022).…”

“…They have been experiencing population declines due to habitat loss, vehicle collisions, and fires (Miranda et al ., 2014; Ascensão & Desbiez, 2022; Noonan et al ., 2022), and are currently classified by the IUCN as vulnerable to extinction, with a risk of local extirpations throughout their range (Miranda et al ., 2014). Their lifespan in the wild is currently unknown, they have a low reproductive rate (Miranda et al ., 2014; Desbiez, Bertassoni & Traylor-Holzer, 2020) and occur at low densities (<1/km 2 ) (Bertassoni, Bianchi & Desbiez, 2021). Ongoing habitat loss throughout their range (Strassburg et al ., 2017) is expected to further threaten their survival.…”

Assessing the impact of roadkill on the persistence of wildlife populations: a case study on the giant anteater

“…Here, we used the giant anteater (Myrmecophaga tridactyla) as a model species to assess the real impact of WVC on local populations of a largesized mammal. This species has a body mass of 33 kg, low recruitment, with about one pup per year (Gaudin et al, 2018), and low densities of < 1 ind./km² (Bertassoni et al, 2021), traits that make them particularly vulnerable to additional non-natural mortality (Fahrig and Rytwinski, 2009;Rytwinski and Fahrig, 2012). Despite its wide distribution throughout Central and South America, this species is listed as "Vulnerable to Extinction", and one of the recognized threats is being recurrently involved in WVC throughout its distribution (Miranda et al, 2014), namely in the Brazilian state of Mato Grosso do Sul (Ascensão et al, 2021(Ascensão et al, , 2017.…”

Can long-past human-modified landscapes maintain biodiversity to any degree? A case of medium- and large-sized terrestrial mammals in an Atlantic Forest-Cerrado agroecosystem

“…Both species have been widely hunted in recent decades and are sensitive to fragmentation and anthropogenic pressures (Gallina et al 2012; Lemos et al 2020a). Also, giant armadillos are rare and elusive, besides occurring on low densities (Lemos et al 2020a; Barros et al 2021; Bertassoni et al 2021), making the species hard to register(Bertassoni et al 2021). PEMA may offer a more protected environment against hunting and with continuous forest cover, factors associated to the presence of both species.…”