Scholarly article on topic 'Current distribution of invasive feral pigs in Brazil: economic impacts and ecological uncertainty'

Current distribution of invasive feral pigs in Brazil: economic impacts and ecological uncertainty Academic research paper on "History and archaeology"

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Natureza & Conservação
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Academic research paper on topic "Current distribution of invasive feral pigs in Brazil: economic impacts and ecological uncertainty"



natureza & conservaçào xxx (2015) xxx-xxx

Natureza & Conservacao

Brazilian Journal of Nature Conservation

Supported by Boticario Group Foundation for Nature Protection

Policy Forum

Current distribution of invasive feral pigs in Brazil: economic impacts and ecological uncertainty

4 qi Felipe Pedrosaa'*, Rafael Salernob, Fabio Vinicius Borges Padilhac, Mauro Galettia

5 a Departamento de Ecología, Universidade Estadual Paulista (UNESP), Rio Claro, SP, Brazil

6 b Nova Safra Consultoria, Sao Paulo, SP, Brazil

7 c Faculdade de Odontologia de Piracicaba, Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP, Brazil

9 article info

11Q2 Article history:

12 Received 13 March 2015

13 Accepted 6 April 2015

14 Available online xxx


Keywords: Sus scrofa Alien species Invasive species Game species Conservation policy

Invasion of feral pigs worldwide is a concern to both biodiversity and human well being. Its harmful effects on ecosystems require control or eradication plans. In Brazil, there were three waves of invasions, and in the past 20 years, we watched an unprecedented invasion of feral pigs. They were progressively released to the wild after the commercial appeal around exotic pig business proved to be unprofitable. Here we present an up to date map of the distribution of feral pig in Brazil, revealing the magnitude of invasion. Federal plan to control feral pig populations arise in different occasions along last 20 years, and the most recent one (IN 03/2013) was in fact intended to protect macro-economic interests, rather than biodiversity or local economies. Relying in the action of hunters to protect biodiversity from the noxious species, the new control policy presents challenges and opportunities to be considered by decision makers.

© 2015 Associacao Brasileira de Ciencia Ecológica e Conservacao. Published by Elsevier

Editora Ltda. All rights reserved.

22 Introduction of species beyond their natural geographic dis-

23 tribution is a major concern for both human well-being and

24 health ecosystems. One of those species is the wild boar

25 Sus scrofa and its feral varieties. Feral forms of S. scrofa fig-

26 ure amongst the harmful alien invasive species (Lowe et

27 al., 2000), because of its impacts on natural and agricultural

28 ecosystems. It has the wider distribution among all terrestrial

29 mammals in the world, and its effects on ecosystem function-

30 ing have been broadly recognized (Barrios-García and Ballari,

31 2012). A set of traits such as plasticity in feeding behavior

(Ballari and Barrios-García, 2014) and high reproductive rates 32

(Dzieciolowski et al., 1992), are associated to the ability of feral 33

pigs to thrive wherever they are introduced. 34

In Brazil, feral pigs first invaded Pantanal ecosystems. They 35

are locally known as "porco-monteiro", a breed of domes- 36

tic pig that escaped into the wild more than 200 years ago 37

(Desbiez et al., 2011). The second wave of invasion of feral 38

pigs in Brazil took place in 1989, coming from Uruguay, when 39

wild boars invaded the south part of Rio Grande do Sul, 40 south of Brazil (Deberdt and Scherer, 2007). The third wave

* Corresponding author. E-mail address (F. Pedrosa). http://dx.doi.Org/10.1016/j.ncon.2015.04.005

1679-0073/© 2015 Associacao Brasileira de Ciencia Ecológica e Conservacao. Published by Elsevier Editora Ltda. All rights reserved.



natureza & conservaçâo xxx (2015) xxx-xxx

"Porco-monteiro" at Pantanal Javali - 1989 at Jaraguâo, RS Javali and javaporcos recorded by Deberdt & Scherer (2007) Javali and javaporcos 2014's records

1:10.000.000 0 125 250 500 km


Fig. 1 - Distribution of feral pig populations and its varieties in Brazil. It first invaded Pantanal ecosystem; they are locally known as "porco-monteiro" a breed of domestic pigs escaped to the wild 200 years ago (yellow). Wild boars appears in Jaguarao-RS in 1989 (red), coming from Uruguay. The records from 2007 (green) are from Deberdt and Scherer (2007), and indicate all feral swine forms. The present work gathered records in the year of 2014 (orange). For complete list of the municipalities, see supplementary material.

41 differs from the two others by context and magnitude. Wild

42 boars were imported in the 1990s from Europe and Canada

43 by swine farmers which trusted in a new commercial appeal,

44 sold to them as "the blue blood in the pigpen", referring to

45 the suppose royalty origin of the species as being a meat of

46 a higher quality (GloboRural, 1996). The commercial promises

47 proved unprofitable. Trying to save the business, many farm-

48 ers bred wild boars with domestic pigs, intending a fattest pig.

49 In fact, the breed resulted a half-bred S. scrofa, bigger than

50 and skittish as pure wild boars, known as "javaporco". By the

51 end of the same decade, the Brazilian Institute of Environ-

52 ment and Renewable Natural Resources (IBAMA) suspended

53 the importation and stopped to concede operating permits

54 to established "exotic" swine farmers (IBAMA, 1998a,b). What

55 followed was a widespread intentional (in some cases unin-

56 tentional) release of half-bred feral pigs (and pure wild boars),

57 in discontinued locations, inaugurating a continental scale

58 invasion (Fig. 1).

59 We encouraged a broad network of people attentive to the

60 issue of feral pigs in Brazil to participate in the effort to gather

61 information on the location of incidence of these animals

62 ( This effort took place from May to

December 2014. Legalized feral pig hunters accounted for the 63

majority of the gathered records. They felt comfortable in shar- 64

ing information, because since 2013 a new rule from IBAMA (IN 65

03/2013) allow for the persecution and slaughter of feral pigs 66

aiming at controlling their population size. It was surprising 67

to note that there are many feral pig hunters in activity and 68

aware that the impacts caused by these animals may get out of 69

control. To avoid misleading information from the collabora- 70

tive network, the only valid information considered was from 71

reports accompanied by pictures from slaughtered or sighted 72

animals. 73

Along with that, we collected data together with Sao Paulo 74

State Environment Secretariat (SMA). The SMA of Sao Paulo 75

implemented the Work Group in Exotic Species, which efforts 76

resulted in an up to date publication about alien species inva- 77

sion in the state (SMA, 2013). We also checked processes from 78

IBAMA sent to SMA in the year of 2014, from citizens of Sao 79

Paulo requesting authorization to control feral pig in third 80

land, and these processes provided new records to us. The 81

media also contributed, since the news about crop damage 82

and other troubles associated to feral pig activity became 83

recurrent, thereby we also accounted the publicized places. 84


natureza & conservaçào xxx (2015) xxx-xxx 3

We found that feral pigs are present in 472 Brazilian municipalities, in four of the five political regions of the country, presenting a pattern of regionally isolated populations (Figs. 1 and Table S1). The most affected region is the southeast (253 municipalities), followed by south (133), midwest (75) and northeast region (9). Sao Paulo is the most affected state (156 municipalities) followed by Minas Gerais (91) and Rio Grande do Sul (55) (see supplementary material). Our records represent an increase of five times on the number of locations invaded since Deberdt (2007; 91 municipalities). We are watching an unforeseen invasion (Kaizer et al., 2014; Trovati and Munerato, 2013).

It is well recognized that feral pigs might cause several economic losses, whether damaging crop fields and attacking livestock or causing indirect losses associated to the budget involved in control programs (Deberdt and Scherer, 2007; Pimentel et al., 2005). An important agro industry from Sao Paulo reported us its losses: 340 ha of maize crop in a year, equivalent to 2.84 thousand tons of grains or around R$1.25 million ($430.000 dollars). The most reported ecological impacts of feral pig invasions are related with its rooting and wallow behavior, which may reduce the cover and diversity of plant species (Hone, 2002), affect soil properties (Barrios-García et al., 2014) and also assist the spread of diseases to wild life (Pejchar and Mooney, 2009). Feral pigs also contribute to the spread of invasive plants (Dovrat et al., 2012).

In fact, the federal plan to control feral pig populations, the IN 03/2013, was edited primarily to protect macro-economic interests. The Brazilian swine business earns 1.5 billion dollars annually from international markets (ABPA, 2014), and the invasion of feral pigs put that market at risk. The World Organization for Animal Health (OIE) modified the rules and procedures to certify the country members as classical swine fever (CSF) free zones (OIE, 2013). Before 2015, CSF was an auto declared disease and the Brazilian Ministry of Agriculture (MAPA) recognized most of the country as CSF free zone (MAPA IN 52/2013), but now it needs an official recognition from OIE, otherwise Brazilian swine products cannot be exported. The national recognition of CSF free zones emerged from MAPA through the Swine Health National Program (MAPA, 2012), and since 2012 the Brazilian Corporation for Agricultural Research (EMBRPA) implemented the epidemiological surveillance in feral swine (EMBRAPA, 2012), attending to an official request from MAPA. Including EMBRAPA expertise in the PSC question is strategic to assure international recognition and keep the market. Therefore, the main motivation to promote and authorize control of feral pigs in Brazil is to prevent a rupture in both ongoing and future commercial relations with international markets.

There is a perception that the harmful effects of feral pigs are associated to high densities in both native and introduced ranges (Hone, 2002; Ickes, 2001), suggesting a threshold of pig densities above which they become noxious. Does this threshold really exist? If so, how to measure it? Below which threshold will feral pig become harmless to economic interests and to biodiversity and ecosystem services? Is the economic and ecological threshold similar? Given the speed of invasion throughout new ranges presented in this work, we believe that control or eradication programs are necessary, despite being difficult to implement. Most of eradication success programs

come from islands (Cruz et al., 2005; Parkes et al., 2010 and ref- 145

erences therein), and continental programs fail to eradicate 146

due to the high capacity that feral pigs have to recover and 147

learn to avoid persecution (Morrison et al., 2007). 148

Finally, the IN 03/2013 relies on the action of hunters to stop 149

the advance of feral pigs in Brazil. This leads to an awkward 150

situation: on the one hand feral pigs may be acting as a shield 151

to other mammals, since they are favorite species of locals for 152

food ingestion (Desbiez et al., 2011), but there is also an evident 153

concern about the increase in wildlife persecution, because 154

most Brazilian ecosystems are highly defaunated due to ille- 155

gal hunting (Galetti et al., 2009; Peres and Palacios, 2007). Even 156

if in near future a new rule determines the prohibition of feral 157

pig control, they may keep doing it, as they have being doing 158

before the legalization. What becomes evident is the need for 159

a regulation on the hunting activity, as it will be a critical part 160

in management of feral pig and other invasive species in near 161

future. For instance, the hare Lepus europaeus, another invasive 162

species (Auricchio and Olmos, 1999) are affecting the economy 163

of small vegetable producers and cannot be legally controlled. 164

The Brazilian Law 5197/1967, historically assumed by the epi- 165

thet "Fauna Protection Law", in fact does not prohibit hunting 166

activity. The law 5197/1967, also known as "Hunting Code", 167

is a bottleneck in biodiversity conservation policy, by neglect- 168

ing to understand technically and scientifically the ecological 169

and economic aspects of the potential game species present 170

in Brazil. 171

Conflicts of interest

The authors declare no conflicts of interest. 172 Acknowledgements

We thank to FAPESP (Biota 2014/50434-0), SISBIO (no. 46150-1), Q3 173

IDEAWild, SMA-SP, Celine C. de Oliveira and to all collabora- 174

tors who send data to FP receives 175

a fellowship from CAPES and MG receives a fellowship from 176

CNPq. 177

Appendix A. Supplementary data

Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j.ncon.2015.04.005.


ABPA, 2014. Associacao Brasileira de Proteína Animal: Os

números das exportares brasileiras de carne suína em 2014, Available from (accessed 20.02.15).

Auricchio, P., Olmos, F., 1999. Northward Range Extension for the European Hare Lepus europaeus Pallas 1778 (Lagomorpha-Leporidae) in Brazil, vol. 2. Publicares Avulsas do Instituto Pau Brasil, pp. 1-5.

Ballari, S.A., Barrios-García, M.N., 2014. A review of wild boar Sus scrofa diet and factors affecting food selection in native and introduced ranges. Mamm. Rev. 44,124-134.



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