Part III: Conservation and Management320
Damages Caused by Sus scrofa Wild Populations
Conflicts between wild pig populations and human activities
have been reported since the introduction of the species as a
domestic animal into South America by European settlements
in the sixteenth century. In former times, the main damages were
subsistence crop attacks (Donkin 1985). Nevertheless, it was
only after the 1980s that the importance and diversification of
reports about damages increased. Between 1987 and 2015, there
were at least 41 original works reporting potential damages of
wild populations of S. scrofa, classified into three dimensions:
environmental, economic and social aspects (Figure 29.4).
The environmental damages of S. scrofa were diversified,
as expected for a generalist species like a pig. A recent global
review listed 27 specific environmental damages in its intro-
duced and native ranges (Barrios-Garcia & Ballari 2012). In
South America, we recorded 12 groups of environmental dam-
ages (Figure 29.4a), such as animal and seed predation (Coblentz
& Baber 1987; Cruz & Cruz 1987; Jackson & Langguth 1987;
Valério 1999; Skewes et al. 2007; Santos et al. 2009; Sanguinetti
& Kitzberger 2010; Batista 2015; Rosa 2015), plant community
change (Itow 1995; Santos et al. 2009; Cuevas et al. 2010; Barrios-
Garcia et al. 2014), prey (Cavalcanti & Gese 2010; Salvador
2012), zoochory (Salvador 2012), soil damage (Barrios-Garcia
et al. 2014), scavenging (Coblentz & Baber 1987), and rooting
(Hegel & Marini 2013).
Competition was the most studied and reported ecological
interaction in the form of environmental damage (Figure 29.4a).
On the other hand, it was also the most controversial. There were
reports of competition with different South American vertebrates,
such as giant tortoises in Galápagos (Ilha de Santiago) (Coblentz
& Baber 1987), pampas deer in the Argentinian Pampas (Pérez
Carusi et al. 2009), and peccaries in Pantanal (Galetti et al. 2015).
The most significant results of potential competitions with pec-
caries were changes in feeding activities due to niche overlap with
S. scrofa in Pantanal (Galetti et al. 2015). The potential competi-
tion with peccaries was expected due to their ecomorphological
traits (Sicuro & Oliveira 2002). However, other works failed to
demonstrate competitions between alien and native wild pigs inPantanal and the Atlantic Forest (Desbiez 2007; Oliveira-Santos
et al. 2011; Salvador 2012; Hofmann 2013).
Economic damages were less diversified (Figure 29.4b)
and likely dependent on the regionally dominant land use. For
example, corn crop attacks were a common economic damage,
but mainly only where there were wild pigs and corn crops as
an important regional economic activity (Bonacic et al. 2010;
Fonseca et al. 2014; Batista 2015; Pedrosa et al. 2015; Poeta
2015). In Southern Brazil, wild boars could damage 5–30 ha/
harvest of corn crops (Salvador 2012). The damages could reach
340 ha of maize crops/year and an estimated 2.84 thousand
tons of grains or around $430,000 dollars in southeastern Brazil
(São Paulo) (Pedrosa et al. 2015).
The crop attacks were a potential social problem in small
farms in general because S. scrofa can damage proportionally
more areas (Figure 29.4c). In Araucaria Forest ecosystem, small
farmers (< 50 ha) had sometimes lost up to 100 per cent of their
crops (Salvador 2012; Batista 2015).
Another common reported socioeconomic damage to livestock
was the risk of an outbreak, as wild pigs may be disease reservoirs
for commercial pig farming (Figure 29.4b). For example, this con-
cern was the reason for the development of National Programmes
of Epidemiologic Surveillance in Brazil and Chile (Skewes & Bustos
2011; Santiago Silva et al. 2013b). However, few works sought to
research this risk in South America (García et al. 2005; Skewes &
Bustos 2011; Santiago Silva et al. 2013a, 2013b, 2013c, 2015).
The risk of an outbreak and its economic consequences, such
as the bankruptcy of the animal farming industry, could also
become a social concern due to the amount of people depend-
ent on the pork production system, especially in southern Brazil
(FAO 2007). Epizootic emerging infections are also a concern.
The first case of human trichinosis in South America, for exam-
ple, was recorded in Chile in 2004 (García et al. 2005). This case
was associated with hunted wild boar (García et al. 2005).
On the other hand, no significant conflict between S. scrofa
and human activities has been detected in regions dominated
by rangeland and forestry (Desbiez 2007; Salvador 2012). The
most representative cases in South America in this regard can
be found in the Brazilian region of Pantanal and the Argentiniancompetition disease reservoir
crop attack
livestock attackcrop attack
water quality
private land invasion
human attack
disease reservoir
bushmeat
00123
Frequency(b)(a)(c)4561 2
Frequencyanimal predation
plant community change
wildlife management
soil damage
prey
zoochory
scavenging
rooting
mycophagy
disease reservoir
036
Frequency91215seed predationFigure 29.4 Frequency of
environmental (a), economic
(b) and social (c) confirmed (grey)
or tested but not confirmed
(blank) damages caused by wild
populations of Sus scrofa in original
works between 1987 and 2015 in
South America..031Downloaded from https://www.cambridge.org/core. Faculty of Classics, University of Cambridge, on 04 Dec 2017 at 12:52:31