In the Atlantic Forest, the lowland tapir is at risk of extinction

Lowland tapir populations in the Atlantic Forest in South America are at risk of almost complete disappearance, scientists have estimated. The main long-term threat to their well-being is population isolation, as hunting and highways keep populations away from each other. Urgent measures need to be taken to connect isolated populations and ensure the long-term conservation of tapirs, warn the authors of a new study published in the open-access journal Neotropical Biology and Conservation.

Lowland tapir populations in the Atlantic Forest in South America are at risk of almost complete disappearance, scientists have estimated. Weighing up to 250 kg, the animal can adapt to most habitats in South America—but its populations continue to decline across its range.

Today, its survival is seriously threatened: it can be found in just 1.78% of its original distributional range in the Atlantic Forest biome, which covers parts of Brazil, Argentina and Paraguay. The main long-term threat to its well-being is population isolation, as hunting and highways keep populations away from each other.

Lowland tapir. Photo by Patricia Medici

Urgent measures need to be taken to connect isolated populations and ensure the long-term conservation of tapirs, warn the authors of a new study on the distribution and conservation status of lowland tapirsin the South American Atlantic Forest, published in the open-access journal Neotropical Biology and Conservation

The research was done by Kevin Flesher, PhD, researcher at the Biodiversity Study Center, Michelin Ecological Reserve, Bahia, and Patrícia Medici, PhD, coordinator of the Lowland Tapir Conservation Initiative, a project developed by the Institute for Ecological Research in Brazil, and chair of the Tapir Specialist Group at the Species Survival Commission in the International Union for Conservation of Nature.

 “Of the 48 tapir populations identified during the study, between 31.3% and 68.8% are demographically unviable (low number of individuals), and between 70.8% and 93.8% of the populations are genetically unviable (low gene flow). Only 3-14 populations are still viable in the long run when both criteria are considered. The evidence suggests that with the appropriate conservation actions, the lowland tapir could be broadly distributed throughout the Atlantic Forest,” says Kevin Flesher. 

Lowland tapir. Photo by Alexander Blanco

“Tapirs have low reproductive potential, including a long reproductive cycle with the birth of just one young after a gestation period of 13-14 months and intervals of up to three years between births. Our populational simulations clearly show how, in the case of small populations, even the loss of a single individual per year can result in rapid extinction of an entire local population,” adds Medici. 

Lowland tapir. Photo by Bill Konstant

Kevin Flesher dedicated 15 years to visiting 93 reserves in the Atlantic Forest, talking to people and analyzing 217 datasets, before he compiled the necessary data to design conservation actions that can ensure the survival of tapirs in the area. 

The states of São Paulo and Paraná in Brazil have the largest number of remaining populations: 14 and 10, respectively. The two largest populations are in Misiones, Argentina, and in the neighboring Iguaçu and Turvo reserves, in Paraná and Rio Grande do Sul, Brazil.

“As far as our knowledge goes, there is no evidence of movement of tapirs between these populations,” points out Medici.

The distance between population fragments, however, is not what is stopping them.

“The central problem is the multiple threats they face while crossing the habitat,” explains Flesher. Highways are one major obstacle that limits the access of tapirs to forests with adequate habitat. “For example, the heavy traffic on highway BR-101 (which cuts the Brazilian Atlantic Forest from North to South) is a death trap to wildlife. Tapirs often die when attempting to cross it,” explains Medici. 

The construction of highways and expansion of traffic in and around natural areas is a serious threat to large tapir populations that might otherwise have the chance to thrive, like those in Misiones, Argentina, and Serra do Mar, Brazil. 

“Roadkill is a significant cause of death in six of the eight reservations in which highways cross tapir populations, and the expansion of the roadway grid in the country threatens to cause population fragmentation in at least four populations,” points out Flesher. This is why finding ways to allow tapirs to cross highways safely is an urgent conservation priority.

Lowland tapir. Photo by Patricia Medici

The results of the study, however, give cause for “cautious optimism” for the future of tapirs in the area: after decades of dedicated conservation efforts, the situation is starting to improve. 

“Despite these continuing challenges for tapir conservation, most populations appear to be stable or increasing and the conservation outlook for the species is better than several decades ago, when the first efforts to protect the species began,” Kevin Flesher concludes.

Research article:

Flesher KM, Medici EP (2022) The distribution and conservation status of Tapirus terrestris in the South American Atlantic Forest. Neotropical Biology and Conservation 17(1): 1-19. https://doi.org/10.3897/neotropical.17.e71867

Safe distance: How to make sure our outdoor activities don’t harm wildlife

Spending time outdoors is good for a person’s body and soul, but how good is it for the wildlife around us?

Outdoor recreation has become a popular activity, especially in the midst of a pandemic, where access to indoor activities might be limited. Long known to have negative behavioural and physiological effects on wildlife, outdoor recreation is one of the biggest threats to protected areas. Human disturbance to animal habitats can lower their survival and reproduction rates, and ultimately shrink populations or eradicate them from areas where they would otherwise thrive. Still, park planners and natural resource managers often can’t find clear recommendations on how to limit these impacts.

Human recreation and wildlife often overlap. Here an American black bear and hikers use the same trail hours apart in Sonoma County, California, USA. Image by the Wildlife Conservation Society

A new scholarly article in the open-access, peer-reviewed journal Nature Conservation from researchers at the Wildlife Conservation Society looked at nearly 40 years of research on recreation impacts on wildlife to try to find the point where recreation starts to impact the wildlife around us. Knowing when and to what extent a species is being disturbed can ultimately allow for more informed and effective management decisions and increase the chances of its successful conservation.

The researchers found that the impact or uncomfortable distance to humans, vehicles or trails for shorebirds and songbirds was as short as 100 meters or even less, whereas for hawks and eagles it was greater than 400 meters. For mammals, it varied even more widely, with an impact threshold of 50 meters for medium-sized rodents. Large ungulates – like elk – would rather have to stay 500 to 1,000 meters away from people.

While human disturbance thresholds can vary widely, large buffer zones around human activities and controlled visitation limits should always be considered during planning and maintenance of parks and protected areas. Based on their findings, the authors recommend that human activities should be considered to be impacting wildlife at least 250 metres away. Further, they call for future research to explicitly identify points where recreation begins or ends to impact wildlife.

Original source:

Dertien JS, Larson CL, Reed SE (2021) Recreation effects on wildlife: a review of potential quantitative thresholds. Nature Conservation 44: 51-68. https://doi.org/10.3897/natureconservation.44.63270

Eleven new species of rain frogs discovered in the tropical Andes

One of the newly described species: Pristimantis chomskyi.
Its name honors Noam Chomsky, a renowned linguist from ASU.
Image by David Velalcázar, BIOWEB-PUCE.

Eleven new to science species of rain frogs are described by two scientists from the Museum of Zoology of the Pontifical Catholic University of Ecuador in the open-access journal ZooKeys. Discovered in the Ecuadorian Andes, the species are characterized in detail on the basis of genetic, morphological, bioacoustic, and ecological features.

On the one hand, the publication is remarkable because of the large number of new species of frogs. Regarding vertebrate animals, most studies only list between one and five new to science species, because of the difficulty of their collection and the copious amount of work involved in the description of each. To put it into perspective, the last time a single article dealt with a similar number of newly discovered frogs from the western hemisphere was in 2007, when Spanish scientist Ignacio de la Riva described twelve species from Bolivia.

The Rain frogs comprise a unique group lacking a tadpole stage of development. Their eggs are laid on land and hatch as tiny froglets.
Image by BIOWEB-PUCE.

On the other hand, the new paper by Nadia Paez and Dr Santiago Ron is astounding due to the fact that it comes as part of the undergraduate thesis of Nadia Paez, a former Biology student at the Pontifical Catholic University, where she was supervised by Professor Santiago Ron. Normally, such a publication would be the result of the efforts of a large team of senior scientists. Currently, Nadia Paez is a PhD student in the Department of Zoology at the University of British Columbia in Canada.

Unfortunately, amongst the findings of concern is that most of the newly described frog species are listed as either Data Deficient or Threatened with extinction, according to the criteria of the International Union for Conservation of Nature (IUCN). All of the studied amphibians appear to have very restricted geographic ranges, spanning less than 2,500 km2. To make matters worse, their habitats are being destroyed by human activities, especially cattle raising, agriculture, and mining.

Amongst the newly described species, there is the peculiar Multicolored Rain Frog, where the name refers to its outstanding color variation. Individuals vary from bright yellow to dark brown. Initially, the studied specimens were assumed to belong to at least two separate species. However, genetic data demonstrated that they represented a single, even if highly variable, species.

Variations of the Multicolored Rain Frog. Its name makes reference to the outstandingly varied colorations within the species.
Image by BIOWEB-PUCE.

The rest of the previously unknown frogs were either named after scientists, who have made significant contributions in their fields, or given the names of the places they were discovered, in order to highlight places of conservation priority.

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Original source:

Paez NB, Ron SR (2019) Systematics of Huicundomantis, a new subgenus of Pristimantis (Anura, Strabomantidae) with extraordinary cryptic diversity and eleven new species. ZooKeys868: 1-112. https://doi.org/10.3897/zookeys.868.26766.