Chapter 24: Collared peccary Pecari spp. (Linnaeus, 1758)261
other Neotropical regions reported lower percentages of fruits
in peccary diets, i.e. 59–66 per cent for both white-lipped and
collared peccaries in the Peruvian Amazon (Kiltie 1981; Bodmer
1989). In the Pantanal (Brazil), the diversity of fruit species con-
sumed was similar between the two species, and diet overlap was
also high (Desbiez et al. 2009). In the Chaco forest the collared
peccaries fed on 128 fruit species and 79 species of seeds (Taber
et al. 2011). The most common fruit in faecal samples from col-
lared peccaries in the Atlantic Forest was a palm (Keuroghlian
et al. 2008). In arid environments of the southern USA, collared
peccaries depend largely on the prickly pear cactus (Opuntia
spp.; Sowls 1997), which is also an important source of water, a lim-
iting resource in this habitat. In the Calakmul Biosphere Reserve,
Mexico, the collared peccary has been observed to frequently
drink, bathe and wallow in temporal water bodies (R. Reyna-
Hurtado, personal observation). Collared peccary may split into
temporary subgroups when foraging (Keuroghlian et al. 2008).
Long-term studies have shown potential impacts of collared
peccaries on seedling demographics in the Amazon. For example,
Beck et al. (2010) and Reider et al. (2013) concluded that defau-
nation of collared peccaries, a species that has disproportional
non-redundant interactions with plants via seed dispersal, preda-
tion, trampling, and herbivory, may eventually change the forest
structure and canopy tree community and affect other species.
Reproduction and Growth
Collared peccary can breed year-round with peaks from November
to March in the temperate zones (Taber et al. 2011). In the Peruvian
Amazon, birth peaks occur in January, July, August, and October
(Taber et al. 2011). The gestation period varies between 138 and
150 days (Lochmiller et al. 1984; Sowls 1997; Mayor et al. 2006a).
In the Amazon, the collared peccary female is considered to be
seasonally polyoestrous (Mayor et al. 2006b) with a pregnancy
rate of 42.5 per cent (Mayor et al. 2006b). In the Peruvian Amazon,
overall, gross annual productivity was 0.89 foetuses/adult female
for collared peccaries (Gottdenker & Bodmer 1998). Reproductive
production of the species in the wild was estimated at 1.12 births/
year (Mayor et al. 2006b). Both males and females have offspring
with more than one partner, showing a promiscuous genetic mat-
ing system (Cooper et al. 2011). The litter size varies from one to
four, but generally one to two newborns are seen following the
mother for several months (Taber et al. 2011). Newborns are able
to follow their mothers within an hour or two after being born.
It has been observed that mothers actively defend their young
by vocalizations and tooth-chattering. Generally juveniles reach
weight and height of an adult at about 40 weeks of age (Sowls 1997).
Behaviour
Social and Community Behaviour
The collared peccary is social and lives in herds. The herd
size varies largely from two to 50 animals but the com-
mon herd size is around 10 animals (Kiltie & Terborgh 1983;
Robinson & Eisenberg 1985; McCoy et al. 1990; Sowls 1997;
Judas & Henry 1999; Mandujano 1999; Keuroghlian et al. 2004;
but see Castellanos 1983). In Arizona, herd size averages 8.5
animals (from a sample size of 127 herds; Knipe 1957 in Sowls
1997). In Calakmul Biosphere Reserve, Mexico, herd size aver-
ages six from a total of 88 observations (Reyna-Hurtado, in
preparation). Robinson and Eisenberg (1985) found averages of
3.1 and 6.5 animals in herds in Panama and Venezuela, respec-
tively. The average number of individuals per herd was 8.8 and
13.5 in fragments of the Atlantic Forest highlands (Keuroghlian
et al. 2004; Cullen et al. 2001, respectively). Peres (1996), study-
ing the population status of peccaries in forests with and without
hunting in the Amazon, found several small groups with aver-
ages of five to eight individuals (N = 16). In the Pantanal, group
size varied between five and 10 individuals (Desbiez et al. 2009).
Collared peccary herds split often into subgroups (Ilse &
Hellgren 1995; Sowls 1997; Judas & Henry 1999; Keuroghlian
et al. 2004). Fragoso (1999) followed two herds, one of 34 and
one of 12 individuals in Maraca Island, Brazil, and observed
that these herds usually split into four subgroups. In the Atlantic
Forest, Keuroghlian et al. (2004) found that radio-tracked herds
would split into groups of one to three individuals during the
day and foraged separately at distances between 30 and 250 m
apart. Oldenburg et al. (1985) reported distances of separation
of a minimum of 100 m to a maximum of 1400 m and most of
the splits lasted less than 12 hours (Sowls 1997). Sightings of
lone collared peccaries or groups of two to three individuals
have frequently been reported from sites in both the Neotropics
and the southwestern USA (Bissonette 1982; Castellanos 1983;
Kiltie & Terborgh 1983; Green et al. 1984; Oldenburg et al. 1985;
Robinson & Eisenberg 1985; Sowls 1997). Keuroghlian et al.
(2004) found that collared peccaries appeared to travel more in
the early morning and late afternoon, when the full herd was
together. During midday, subherds would usually remain forag-
ing in a relatively restricted area. They also spent a good part of
late morning and early afternoon resting in cavities excavated
at the bases of large trees, next to fallen trunks, or in other cool
locations (Sowls 1997; Keuroghlian et al. 2004). This period of
inactivity was also observed in the Paraguayan Chaco (Taber
et al. 1994). Herd members maintained contact by vocalizing
and releasing strong liquid musk from the dorsal gland.
The dorsal gland of the collared peccary contains both seba-
ceous and sudoriferous secretory tissues that produce some 20
volatile components, some specific to males or females. They
deposit scent on each other, as well as on tree trunks, rocks,
and other objects (Sowls 1997; Taber et al. 2011). Eight types of
vocalizations have been identified including purring, grunting,
barking, woofing, growling, and squealing as well as jaw snap-
ping (Sowls 1997; Taber et al. 2011). Byers (1980), Bissonette
(1982) and Sowls (1997), among others, have described in detail
the behavioural repertoire of collared peccary social commu-
nication. Some friendly interactions that arise are the touching
of nasal disc as a form of greeting and the rubbing of the dor-
sal gland as a way to maintain group cohesiveness and member
identification (Sowls 1997). Although there is no clear domi-
nance hierarchy among members of a herd, there are frequent
aggressive interactions among members that includes a behav-
iour named ‘squabble’ (Schweinsburg & Sowls 1972), described
as when two animals face each other in a sparring position and
tooth-chattering accompanies the action. Tooth-chattering is.02612:46:11