The low reproductive productivity of lowland tapir measured as rmax
(intrinsic rate of natural increase) appears to influence this susceptibility to
overhunting. Indeed, the reproductive productivity of sympatric Amazonian game mammals,
measured as rmax correlates well with the susceptibility of species to
overhunting. Species with high values of rmax are less susceptible to
population declines due to hunting than species with lower values of rmax
(Bodmer 1995). Lowland tapir have a relatively low value of rmax and are
accordingly susceptible to overhunting.
Hunting as a threat in other regions: Colombia, Venezuela,
French Guiana, Brazil, and Argentina
Indeed, overhunting is a major threat to the lowland tapir throughout its range. In
Colombia the species is listed as endangered due to indiscriminate hunting, among other
factors (Inderena 1986). Local extinction has occurred in certain areas of the Venezuelan
Llanos, where a single individual sighted in the early 1980s was the first record from
that area in approximately three decades. Although listed as a game species in French
Guiana, tapirs have decreased in hunted regions versus non-hunted regions (C. Julliot
pers. comm.). Additionally, overhunting is a major threat in parts of the Brazilian Amazon
and Cerrado including the states of Roraima, Acre, Rondônia, Mato Grosso, and Goias
(Fragoso, Leeuwenberg in litt.); the South Atlantic forest including the states of
Espirito Santo, São Paulo, and Paraná (Pinder, Chiarello, Olmos in litt., Galetti and
Chivers 1995); and northern Argentina (Barquez et al. 1991) among other places.
Non-food use of tapir in Paraguay, Argentina, and Peru
Paraguayan and Peruvian aristocracy sometimes keep pets on their estate lawns where the
animals are poorly cared for and often succumb to malnutrition, resulting in more animals
being taken from the wild (Brooks 1991, n.d.). Paraguayan mission Indians (primarily
Moros) use the thick hide to make sandals which are frequently purchased by tourists as
souvenirs(Brooks 1991). Similarly in north-central Argentina tapirs are becoming scarce
due to hunting for the hide (Mercolli and Yanosky 1991). In north-central Argentina it was
common to use tapir hide from the backstrap, neck, and front legs to make reins and
harnesses (Chalukian in litt.). Today these are mostly used by wealthy ranchers as
ornamentation (Chalukian in litt.).
Lowland tapir range throughout the tropical forests and savannahs of South America.
However, lowland tapir do not use all of these habitats evenly, but selectively use
certain landscape features, particularly those important as food sources. One food type of
importance to lowland tapir are the palm fruits. Indeed, lowland tapir consume large
quantities of fruit for their body size. In a study in northeastern Peru fruit constituted
33% of tapir diets, while leaf and fiber constituted 66% of tapir diets (Bodmer 1990). The
fruits consumed most frequently by lowland tapir are palm species, especially the pulp of
the Mauritia flexuosa palm (Bodmer 1990) and the pulp and seed of the Maximilliana
maripa palm (Fragoso 1994). Other palm fruits commonly consumed by lowland tapir
include those from the Oenocarpus bataua, Scheelea sp, and Euterpe
edulis palms (M. Galetti pers. comm.).
Lowland tapir actively search for stands of palm trees and selectively use these
habitats. In addition, lowland tapir play an important role in the maintenance of palm
forests through seed dispersal (Fragoso 1994, Bodmer 1991, Rodrigues et al.
1993). Through spit dispersal the tapirs disperse Mauritia flexuosa seeds within
palm patches (Bodmer 1991). This enables young Mauritia flexuosa plants to grow
in areas away from the parent plant and in areas with less competition for sunlight.
Lowland tapirs are the most effective dispenser of Maximilliana maripa on
Maracá island in northern Brazil (Fragoso 1994). Tapirs disperse Maximilliana maripa
by passing seeds whole through their digestive tract and defecating the seeds in clumped
areas known as latrines.
Rodents in turn often act as secondary dispensers and remove Maximilliana maripa
from tapir defecations (Fragoso 1994).
Threats to palm forest in Amazonia and other regions
Rural people throughout South America also harvest large amounts of palm fruit. Palm
fruits are the most important non-timber plant resource in the Amazon and contribute 61%
of the market value for wild fruit production in the Peruvian Amazon (calculated from
Peters et al. 1989), with fruits of Mauritia flexuosa and Oenocarpus
batana being most important Mauritia flexuosa palms occur in virtually
monotypic stands in the Peruvian Amazon and account for approximately 2.35%, of the
Peruvian rainforest (CORESPA 1986).
In the Peruvian Amazon Mauritia flexuosa and Oenocarpus batana are
being cut down at alarming rates to harvest fruits (Vasquez and Gentry 1989). Rural people
cut palms, because the physical structure and height of the trees render climbing almost
impossible and very dangerous. For example, Mauritia flexuosa trees often reach
40m in height and have a stegmata wood bark (containing silica bodies) that is extremely
hard and slippery (Uhl and Dransfield 1987). Harvesting of fruit is leading to the local
extinction Mauritia flexuosa in many areas of the Peruvian Amazon. Indeed, the
patchy distribution of this palm helps rural people in locating and collecting fruits.
Harvesting of Mauritia flexuosa has already destroyed many palm swamps close to
villages.
Threats to palm forest are prevalent in other regions besides Amazonia. Overharvest of
palm hearts, especially of Euterpe edulis, which is a favored food of the tapir,
remains a serious threat in São Paulo, Brazil (Galetti and Aleixo 1995). Additionally,
the overharvesting of palms is also a threat in the Brazilian Cerrado (Leeuwenberg in
litt.).
Unfortunately, both tapir and people use palm fruits. In contrast to rural inhabitants,
the tapir helps maintain productive palm forests by dispersing seeds. Thus, the tapir
plays an important role in the production of many palm plants.
Rural people in many parts of South America sell palm products in the city markets and
these products provide important income for many rural households. By destroying the palm
forests, local people are also harming tapir populations by reducing the potential
nutrient intake of tapirs, which in turn will lower their reproduction levels. This in
turn will make tapir populations even more susceptible to local extinctions, especially if
hunting is concurrent with the destruction of palm forests.
Threats to other habitats in Guyana, Suriname, Brazil, Paraguay, and Argentina
Considering the tightly coupled mutualism between tapirs and palms, preservation of
palm habitat is imperative to maintain tapir populations. Destruction of other types of
habitat is rampant in other parts of the lowland tapirs range. Although such landscapes
are not always characterized by a palm dominated plant community, it is equally important
to identify threats to these other tapir habitats.
The Guyana Shield and Cerrado: Logging, mining, and road building
activities are increasing throughout Guyana (Parker et a/. 1993) and Malaysian timber
companies are beginning to invade Suriname (Barongi pers. comm.). Fragmentation and
isolation of suitable habitat is the major threat to tapir in the Cerrado of Acre,
Rondônia, Mato Grosso, and Goias, Brazil (Leeuwenberg in litt.). Since the late 1970s the
major threat to tapir in the Cerrado has been its conversion to soybean megaplantations
mainly for export (Olmos in litt.).
The South Atlantic Forest: Only 8% of native forest remains in
Espirito Santo, Brazil, and illegal logging still occurs (Chiarello in litt.).
Clear-cutting for pasture-lands and soybean plantations is the major threat to tapir where
the South Atlantic forest borders the Brazilian Pantanal (Pinder in litt.). Poorly managed
timbering and development for extensive coffee and sugarcane plantations has resulted in
nearly complete deforestation in the Atlantic forest of São Paulo, Brazil, with less than
8% of the native forest surviving mostly in the coastal mountains (Olmos in litt.).
Surveys in the northeastern Paraguayan Oriental (Dpto. Curuguaty) failed to reveal
evidence of tapir in areas with timber activity (Brooks pers. obs.).
The Chaco: The Paraguayan Chaco is being cleared primarily for cattle
land (Brooks pers. obs.). Moreover the Ruta Trans-Chaco highway which bisects the Chaco
horizontally was initiated in the 1960s and is expanding at a rate of approximately
28km/year (Benirshcke et al. 1989). Construction of this road facilitates access
into all parts of the Chaco. Habitat conversion is one of the major threats to tapir in
northern Argentina (Barquez et al. 1991). In north-central Argentina the greatest
threat to tapir is largely attributed to increased agriculture causing environmental
deterioration (Mercolli and Yanosky 1991).
Some countries have too few protected reserves. For example in the entire country of
Guyana there was only one established reserve in the early 1990s (Parker et al.
1993). In other cases protected areas are not of sufficient size to maintain populations
of at least 500 tapir (Redford and Robinson 1991). At least 72% of Brazilian parks in
tropical humid rain forest, and 32% of Amazonian conservation units are too small to
maintain populations of at least 500 lowland tapirs (Redford and Robinson 1991). Although
tapirs currently survive in fragmented islands of at least 15km2 in South
Atlantic forest, it is likely that populations will not be able to survive in fragments
smaller than 50km2 in the long term (Chiarello in litt.). Additionally,
fragmented populations without corridors will be subject to the deleterious effects of
inbreeding, decreased encounter-rates among individuals for reproduction, and overcrowding
due to insufficient dispersal routes.
In addition to the size of a reserve, its distance from human settlements is also
important. For example, lowland tapir populations in Maraca Island Reserve, Roraima
(Fragoso in litt.), Iguacu National Park, Paraná (Pinder in litt.), reserves in Espirito
Santo (Chiarello in litt.), Serra do Mar and in the vicinity of Morro do Diabo State Parks
in São Paulo (Olmos in litt., Galetti and Chivers 1995), and perhaps other reserves and
parks in Brazil suffer from poaching (Pinder in litt.). The lowland tapir was one of the
species recently extirpated by poachers at Ilha do Cardoso State Park (P. Martuscelli
pers. comm.). Another source of mortality is the roads that cross the Morro do Diabo and
Serra do Mar parks; tapirs being regularly found as road-kills (Olmos in litt.).
Colonization of remote areas is the major threat overall in Roraima (Fragoso in litt.) and
São Paulo, Brazil (Olmos in litt.). An additional threat is that parks are often
understaffed and poorly equipped (Galetti and Chivers 1995). As a model, Defensores del
Chaco National Park, Paraguay has a low human population ,and therefore supports the most
concentrated tapir populations in the Paraguayan Chaco (Brooks 1991). Low human
populations enhance tapir populations, due to reduced hunting, less disturbance, or a
combination of these factors.
