Tapirs are notoriously hard to find and directly observe in the wild. Because of this, little is known about how species behave in their natural habitats. But in a study published in PLOS ONE, researchers found a way around this complication by using tapir DNA to shed light on their behavior.
The team sequenced and compared the DNA of individual tapirs to determine how related they were to one another, and in so doing, determine how far they dispersed throughout their habitat. This study marked the first time this specific technique had been used in the Amazon region.
“I think that people who want to work with conservation should be open to use all kinds of tools, and interdisciplinary studies can bring very interesting results,” co-author Gabriela Pinho, from Brazil’s Instituto Nacional de Pesquisas da Amazônia (National Institute of Amazonian Research), told mongabay.com.
A lowland tapir (Tapirus terrestris) crosses a road in the Pantanal. This species is listed as Vulnerable by the IUCN. Photo by Rhett A. Butler.
Pinho used DNA obtained from lowland tapirs (Tapirus terrestris) in the Balbina Reservoir, created in 1987 by the Balbina Dam in the central Amazon. Tapirs have been little studied in the region; Pinho sought to help fill this gap by researching tapir social behavior via estimates of relatedness between individuals using non-invasive sampling of feces.
“I chose to work on non-invasive sampling of tapirs to uncover aspects of their social behavior for several reasons,” Pinho told mongabay.com. “First of all, the use of DNA extracted from feces to estimate relationship between individuals was never used in the Amazon, and, if…successful [for this study], it could be used for other species. Second, the tapirs are the biggest mammals in South America and there is an incredible lack of knowledge about their behavior and population dynamics.”
Tapirs, which are listed as Vulnerable by the IUCN, are difficult to study because they are both solitary and nocturnal. Much of the battle in traditional observational studies involves first locating a tapir, and then finding a way to observe the rare direct interactions between them. Indirect data collection, such as sampling feces, allows scientists to learn about tapirs without having to actually locate them.
Tapirs are large, herbivorous mammals native to Central and South America, and Southeast Asia. They are superficially similar to pigs, have a long prehensile snout, and are most closely related to horses and rhinoceroses.
A lowland tapir in Yasuni National Forest in Ecuador. Like horses and rhinoceroses, tapirs are classified as odd-toed ungulates. Photo by Jeremy Hance.
“Tapirs are quite unique,” Pinho said. “[They] look like a mixture between a pig, elephant, and a horse, with a small and very flexible snout, dark skin, short mane, horse-like ears, and almost no tail.”
Lowland tapirs can grow upwards of 400-660 pounds (180-300 kilograms). However, despite their size, they are quiet and shy.
“You can notice them just when they are very close and step with their big hooves in a root or whistle to communicate with other individuals,” Pinho said. “But, when encountered in the forest, they tend to dive (they are very good swimmers) or run away.” She added that the sound of a running tapir is “close to a mini tractor.”
The team used a basic DNA-isolation kit, called QIAAmp DNA Stool Mini Kit (QIAGEN). According to the company website, the kit takes just 50 minutes to get results. The team got its DNA samples from the tapir feces, which, according to Pinho, are “not easy to find in the dense forest.” The team overcame the painstaking process of looking for feces in the middle of the Amazon by using footprints on the margin of the islands as an indicator of the presence of tapirs and, therefore, tapir feces in the Balbina Reservoir. In total, the team found approximately 1,000 feces samples over the course of 55 days. For Pinho, “it was not an easy life!”
All samples were analyzed in the Laboratory of Evolution and Animal Genetics (LEGAL), at Federal University of Amazonas. The DNA is concentrated in the shed intestinal cells on the surface of dung. Because of the hot and humid Amazonian climate where the fecal samples were found, they degraded quickly. After only 15 days in the lab, the team observed that the DNA would decay to the point of uselessness. Of the 1,000 samples that the team found, only 32 could be used in the study. Multiple DNA extractions were needed for each sample. However, considering that tapirs are so hard to sample, the researchers considered this to be a good sample size.
A young lowland tapir. This species is also known as the Brazilian tapir and South American tapir. Photo by Rhett A. Butler.
The researchers found that all their samples came from just one expansive tapir population in the Balbina Reservoir region. This means that individuals ranged far and wide, even crossing a large dammed river, to mix with other groups.
“In this study, we generated novel information about lowland tapir social behavior,” Pinho said. “It’s basic information that can be used for tapir population management and, while there is no similar study for the other tapir species, it is a good approximation.”
Still, the study recommends caution when using its results to signify behavior patterns.
“This study was developed in an area impacted by a dam and we do not know if the tapirs’ natural behavior was disturbed by the flooding in the area or not,” Pinho said.
Pinho is collaborating with the Lowland Tapir Conservation Initiative ( LTCI-IPÊ, www.tapirconservation.org.br) and using genetics techniques to estimate the relatedness between already-monitored tapirs in environments undisturbed by human activity. By comparing the results of natural areas to those with dam development, they will be able to more effectively evaluate the impact of large human disturbance on the social behaviors of tapirs.
Citations:
- Pinho GM, Gonçalves da Silva A, Hrbek T, Venticinque EM, Farias IP (2014) Kinship and Social Behavior of Lowland Tapirs (Tapirus terrestris) in a Central Amazon Landscape. PLoS ONE 9(3): e92507. doi:10.1371/journal.pone.0092507
- Naveda, A., de Thoisy, B., Richard-Hansen, C., Torres, D.A., Salas, L., Wallance, R., Chalukian, S. & de Bustos, S. 2008. Tapirus terrestris. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. . Downloaded on 22 April 2014.
Related articles
Large-scale Amazon deforestation or drying would have dire global consequences
(02/21/2008) A new study shows that large-scale degradation of the Amazon, either through drying or continued deforestation, would have global consequence, including worsening climate change, causing regional vegetation shifts, and increasing dust in the atmosphere.
Ancient Amazon fires linked to human populations
(02/20/2008) Analysis of soil charcoal in South America confirms that from a historical perspective, fire is rare in the Amazon rainforest, but when it does occur, it appears linked to human activities. The research, published in Philosophical Transactions of the Royal Society B, is based on dating of soil carbon, which provides a good indication of when fires occurred in Amazonia, according to lead author Mark Bush, head of the Department of Biology at Florida Institute of Technology.
Global warming – not el Nino – drove severe Amazon drought in 2005
(02/20/2008) One of the worst droughts on record in the Amazon was caused by high temperatures in the Atlantic rather than el Nino. The research, published in Philosophical Transactions of the Royal Society B, suggests that human-driven warming is already affecting the climate of Earth’s largest rainforest.
conservation strategies can mitigate the impact of global warming in the Amazon
(02/19/2008) Careful design of protected areas to safeguard key “refugia” and allow for migration can increase the resilience of Amazon biodiversity to climate change, report researchers writing in Philosophical Transactions of the Royal Society B.
Amazon riparian zones need to be expanded to protect wildlife finds study
(02/19/2008) Strips of forest mandated by Brazilian law along rivers and streams in the Amazon rainforest are too narrow to effectively safeguard biodiversity, reports new research published in the journal conservation Biology.
Small Amazon farmers especially vulnerable to climate change
(02/19/2008) Communicating the impact of climate change to small farmers in the Amazon will be key in helping them adapt to higher temperatures, more frequent and intense drought, and greater incidence of forest fires forecast for the region, according to a paper published in Philosophical Transactions of the Royal Society B.
Fire policy is key to reducing the impact of drought on the Amazon
(02/19/2008) Gaining control over the setting of fires for land-clearing in the Amazon is key to reducing deforestation and the impact of severe drought on the region’s forests, write researchers in a paper published in Philosophical Transactions of the Royal Society B.
Cheap ranch loans may be driving jump in Amazon deforestation
(02/12/2008) Surging deforestation in the Brazilian Amazon may be partly the result of new financial incentives given by state banks such as the Bank of Amazon (BASA), reports Agencia de Noticias da Amazonia, a Brazilian newspaper, and the International Tropical Timber Organization (ITTO).