Ecology, Conservation and Management of Wild Pigs and Peccaries

Part II: Species Accounts

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spp. are the most abundant species of the dense shrub layer,

while the ground cover is formed mostly by bromeliads and cac-

tii, such as Opuntia sp., Cleistocactus baumannii and Eriocereus

guelichii (Mayer & Brandt 1982; Taber et al. 1993). There are

some open grassland areas resulting from bush clearing and

fire. Chacoan peccaries are also found in open woodland, but

this seems to be a marginal habitat for the species.

Population Densities

There is scarce information on Chacoan peccary densities and

these have been inferred through indirect methods. These

estimates vary enormously in the literature, from less than

1 ind./km^2 to as high as 9.2 ind./km^2 (Mayer & Brandt 1982).

In the early 1990s, Taber (1991) found a low population in

Argentina with a fragmented distribution and evidence of small,

fragmented populations in Bolivia. He concluded that very little

suitable habitat remained in Argentina and Bolivia, and that the

largest Chacoan peccary populations were in Paraguay. Taber

(1993) estimated a population of 5000 individuals in Paraguay

with a density of 0.43 ind./km^2. In Argentina, Altrichter (2005)

estimated an average density of 0.17 ind./km^2 in hunted areas

and 0.44 ind./km^2 in non-hunted areas.

Altrichter (personal observation) estimated a population of

3200 individuals in the Argentine Chaco using data on density

and remaining habitat for the species in 2002. However, in 2003

a massive deforestation for soybean and cattle ranching started

in the region, and newer population estimates do not exist. In

another study conducted in the Argentine Chaco, Altrichter and

Boaglio (2004) found that the Chacoan peccary was the rarest of

the three species of peccaries living in the area as well as the most

vulnerable to human disturbance.

Movements and Home Range

The Chacoan peccary is territorial. Herd home range sizes in the

Paraguayan Chaco have been estimated to be about 1100 ha in

average with a core area of about 600 ha, based on 95 per cent

Minimum Convex Polygons. Daily ranges average 18.2 ha and

daily travel distances average 2.2 km (Taber et al. 1993). There

has not been more recent home-range estimates.

Activity Patterns

Chacoan peccaries are more diurnal than the other two sym-

patric peccary species in the Chaco. They become active about

sunrise, are active throughout the day and become inactive at

dusk (Taber 1991). Most of the activity occurs between 6 am and

midday. During the hot part of the day herds rest under brush or

along roads under tall trees (Mayer & Brandt 1982). Taber et al.

(1993) found that radio-tracked herds were continually on the

move within the home range, shown by a largely different area

being used every day over an approximate 42-day cycle.

Feeding Ecology

Chacoan peccaries’ principal food resources include different

species of Cacti, i.e. Cleistocactus, Eriocereus, Quiabentia, and

Opuntia (Figure 23.5). They can remove the spines by rolling

pieces of cacti leaves on the ground as well as pulling off the

spines with their teeth. They also consume fallen cactus flowers

and fruits and seeds from various species of Acacia and Prosopis,

and occasionally browse on forbs (Mayer & Brandt 1982; Taber

1991; Taber et al. 1993). This species digs less for food than the

other two peccaries, although it has been observed to consume

the roots of bromeliads (Taber 1991). Mayer and Brandt (1982)

did not find evidence of meat consumption although it has

been observed, in captivity, that if they have the option, animals

would consume meat scraps. Chacoan peccaries lick and eat

mineral-rich soil from naturally occurring salt-licks and leaf-

cutter ant mounds. The Chacoan peccary habitats can lack sur-

face water during the dry season. Taber et al. (1993), following

radio-tracked animals, observed that home ranges contained no

surface water during the dry season, and concluded the Chacoan

Figure 23.5 Adult Chacoan peccary

feeding on Opuntia spp. (photo by

Andrew Taber).

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