Introduction

There are many forms of interaction between humans and animals, including their uses for entertainment purposes (contemplation in zoos, aquariums, and safaris); for transport; generation of energy (traction animals); combating drug trafficking; for sports and warfare activities; and, most frequently, as pets [1]. Millions of people keep many varieties of both domestic and wild animals in their homes [234–5]. Although predominantly birds and mammals (principally dogs and cats) are kept as pets, other groups, including reptiles, fish, amphibians, and even some invertebrates, are becoming common [67–8]. The sociocultural, economic, and environmental implications of these practices are numerous.

In Brazil, wild animals have been kept for companionship for centuries, a very traditional and very widely disseminated practice that involves hundreds of species [2]. This tradition has stimulated the trapping and illegal commerce of many native animals, as most are captured in the wild [2, 910–11], with important implications for animal conservation in the country [9, 1213–14]. The custom of keeping pets is as old as human occupation of the semiarid region of northeastern Brazil, and has been identified as an important factor in strong declines in many local species of wild animals. Most research has focused only on wild birds kept as pets [9, 1516–17] – indicating the importance of this group in that region – but many other types of animals are involved, especially reptiles and mammals.

We sought new information on the use of wild animals as pets in a semiarid area of Northeast Brazil, where this practice is widespread. Using an ethnozoological approach, we examined the following hypotheses: a) most people who keep pets choose to have traditional domesticated cats and dogs and are inhibited by legal implications from keeping wild animals; b) among those who keep wild vertebrates, birds are the principal species; and c) the local practice of keeping wild animals is independent of the socioeconomic status (income, age, sex) of their owners. We hope the results of our research will be useful in devising conservation strategies for protecting wild animals in the semiarid region of Brazil.

Methods

Study area

The present study was carried out in the municipality of Santa Luzia, which is situated in the Seridó Ocidental microregion of Paraíba State, Brazil (Fig. 1) (06º 52′ 20″ S × 36º 55′ 07″ W). The local population is approximately 14,700 (ca. 7,100 men and 7,600 women) in an area of 456 Km², yielding a population density of ca. 32 inhabitants/Km² [18].

Fig. 1.

Location of the municipality of Santa Luzia in Paraíba State, Brazil, showing neighborhoods surveyed (A- Nossa senhora de Fátima, B- Centra, C - São José).

The regional climate is hot semiarid, with average monthly temperatures oscillating between 25 and 28 ºC. Rainfall averages approximately 550 mm per year, with precipitation concentrated between the months of January and April, although there have been periods of great irregularity in rainfall rates in recent decades throughout the entire region [19].

Results

Pets Keepers's profile

We visited a total of 1,195 homes, of which 463 (38.7%) did not keep any pets. In all other residences visited (n=732, 61.3%) pets were present. Considering only those residences which had pets, 641 (88%) kept only domesticated species; 51 (7%) kept only wild species; and 40 (5%) kept both wild and domesticated species simultaneously.

The profiles of the interviewees keeping pets are presented in detail in Table 1. It can be seen that the majority of the people raised only domesticated animals (cats and dogs), and most of them earned up to two minimum-wage salaries. The minimum-wage salary during the research period (2014) was R$ 724 (US$ 302 per month). The interviewees were distributed among many age categories, but were predominately between 20 and 40 years old. They had different levels of schooling, with most having completed high school (Table 1).

Table 1.

Socio-economic profiles of pet owners interviewed in the research project, categorized into groups that raised: 1) only domesticated animals, 2) only wild animals, and 3) both domesticated and wild species.

Species richness of kept animals

A total of 238 specimens were encountered in the residences of the interviewees who kept wild animals as pets (n=91). These specimens corresponded to 31 species distributed among 11 families (Appendix 1). Of all the species encountered, birds were the most representative group both in numbers of specimens (n=231, 97%) and numbers of species (n=28, 90%). Other groups represented were mammals (n= 2 species, 6%) and reptiles (n=1 species, 3%). Of the total of 31 wild species recorded, 25 (80%) were listed as threatened with extinction [24]. Most of these species (n=24), however, were listed in the Least Concern category according to the IUCN, with only one bird species (the Yellow-faced Siskin Sporagra yarrellii) classified as Vulnerable. This latter species is also listed in the Redbook of the Brazilian Fauna Threatened with Extinction under the category Vulnerable [25].

The total number of wild species recorded (n=31) was less than the estimated richness using Chao 1 (33 species). The rarification curve comparing the number of observed species with the estimated richness of wild species kept as domestic pets revealed that the observed richness approached the richness projected by the estimator (93.7%), demonstrating sufficient sampling and a large richness of wild species being kept as pets (Fig. 2).

Fig. 2.

Rarefaction curve of species (Chao 2), comparing the number of observed species (Sobs) and the estimated richness of wild species being kept as pets in the municipality of Santa Luzia-PB.

The principal families in terms of the numbers of species recorded were Thraupidae (39%), Columbidae (19%), and Icteridae (10%). The most frequently encountered species in the homes of the interviewees were: Red-cowled Cardinal Paroaria dominicana (n= 36 specimens), White-throated Seedeater Sporophila albogularis (n=33), Cactus Parakeet Eupsittula cactorum (n=29), Capped Seedeater Sporophila bouvreuil (n=18), Ultramarine grosbeak Cyanoloxia brissonii (n=15), and Campo Troupial Icterus jamacaii (n=15).

The pets being kept by the interviewees were obtained in a number of different manners, principally by directly capturing them (n=35 interviewees, 38.5%) or as gifts (n=35, 38.5%). The balance of the interviewees (n=21, 23%) had bought the wild specimens that they were keeping, indicating their encouragement of the illegal commerce of wild animals in the region. However they obtained the animals they kept, the majority of the interviewees indicated that they kept pets because they “liked them” (n=69, 76%) (as companion animals) and because they enjoyed their “singing” (n=11, 12%) (in the case of birds), while 12% raised animals to sell them.

Discussion

Our results demonstrated that the option to keep domestic pets (cats, dogs and domesticated birds) instead of wild species is a positive tendency from a conservationist perspective, as fewer wild animals would be removed from the natural environment. This result supports our hypothesis that the presence of a domestic pet has a positive conservationist implication in mitigating the desire to keep a native wild animal. Obviously, the predominant presence of domestic animals among pet owners is influenced by current legislation (Federal Law N° 5.197 of January 3, 1967), which prohibits capturing, raising, or commercializing the native wild fauna of Brazil. Within this construct, active controls by environmental agencies, and publicity about the penalties for keeping these animals, have significantly contributed to the safer choice of domesticated animals as pets.

Keeping wild animals in captivity is nonetheless a deeply rooted cultural practice throughout Brazil [2, 9, 10, 26, 27], which persists in spite of many legal implications – as was observed in the present research, with numerous citizens keeping wild animals as pets, independent of numerous socioeconomic variables among their owners (income, age, civil standing, sex, and education level). There was, however, little variation in the socioeconomic profiles of those owners, which impedes a more refined discussion of this point.

As expected, our results confirmed that birds were the most representative group of wild vertebrates kept as pets in the research area. The number of species of wild birds recorded here (n=28) is similar to the findings of other ethno-ornithological research projects undertaken in other localities in the semiarid region of Paraíba State, such as the municipalities of Catolé do Rocha [17] and Santana dos Garrotes [15], where 38 and 41 species of native birds were kept as pets respectively. Similar situations have been reported from other states in the semiarid region of northeastern Brazil, such as in the municipality of Serra Negra do Norte in Rio Grande do Norte State [28] and in four different municipalities in Ceará State [9] where 20 and 44 wild native bird species were kept as pets respectively. Our research also corroborated observations by Albuquerque et al. [29] that the market for pets appears to be the principal stimulus for capturing wild native birds in the semiarid region of northeastern Brazil.

It is well-established that, in addition to birds, other vertebrates are commonly kept as pets, including fish, mammals, amphibians, and reptiles [8]. Our results suggested, however, that the residents of the semiarid region of Brazil demonstrated a significant and widely disseminated preference for birds as vertebrate pets. The popularity of birds is not restricted to the semiarid region, however, but can be seen throughout the country, stimulating an enormous illegal trade that involves at least 295 species of native Brazilian birds [2].

In addition to birds, at least three species of wild vertebrates belonging to other taxa were encountered during our research: Red-footed tortoise Chelonoidis carbonarius, E. sexcinctus, and Common marmoset Callithrix jacchus. The presence of the Red-footed tortoise was not unexpected, as various species of the genus Chelonoidis are widely raised and sold as pets in Brazil [3031–32]. Alves et al. [33] pointed out that Red-footed tortoise is one of the most popular native reptiles kept as pets in the semiarid region of northeastern Brazil, as they are relatively docile, easily captured, and easy to maintain in captivity. The popular belief that their presence in a home helps prevent respiratory diseases such as bronchitis and asthma also favors their maintenance in captivity [30, 33, 34].

Similarly, the presence of marmoset monkeys, C. jacchus, being kept as pets was not surprising, as these animals are widely domesticated over their entire area of natural occurrence [35]. These authors noted that these monkeys, frequently captured by contraband agents to be sold as pets [36, 37], are usually kept chained, in cages, or even free in their owner's houses, depending on the dietary resources offered to them. The other mammal encountered during our research was the yellow armadillo E. sexcinctus, an important species in the semiarid region widely used for food [12, 13]. This animal is often kept in captivity to be fattened and to “clean” its meat for eventual human consumption, as it is a generalist species and is known to consume the remains of other animals in various stages of decomposition. In our survey, however, the yellow armadillo we encountered was being kept as a pet, and its owner affirmed that he had no intention of eating it.

All of the wild native bird species recorded during our survey are also kept as pets in other parts of Brazil [2, 10, 17, 38], confirming that the capture and keeping of these species are quite widespread and that they suffer intense pressure from continuous and widespread persecution. Songbirds are frequently kept specifically for their singing abilities. According to Pagano et al. [38], their songs make them quite valuable on the illicit wild animal market. Alves et al. [12,15,17] noted that the practice of keeping wild native animals as pets has driven many species to high levels of vulnerability, as this human custom transcends generations, and continual capture removes many individuals from the breeding pool. It is important to stress that the inappropriate conditions to which many wild birds are subjected after capture often cause their deaths [15, 3940–41], intensifying impacts on their natural populations.

In the specific case of birds, the high numbers of specimens of the genus Sporophila encountered in the domiciles visited (n=60) corroborates observations made during similar studies in Paraíba State [15, 17, 42, 43] and affirms that the preference given to the birds of this genus is associated with their low monetary costs and easy maintenance [40]. Of all of the species identified in the present survey, S. yarrelli merits special attention as it is known to be threatened with extinction, with the status of “vulnerable” on the red lists of both the Brazil [25] and IUCN [24].

Implications for conservation

Brazil has a rich faunal diversity, with many species valued as pets. The practice of capturing and sequestering wild animals as pets has, however, negative consequences on the animals themselves and the ecosystems from which they were subtracted [17].

In the specific case of keeping wild native animals, the ecological impacts on their populations are obvious, especially when holding them as pets stimulates an illegal commerce to meet that demand – often threatening their very existence. The illegal traffic in wild animals, including their use as pets, has direct impacts on the populations of those species, which generates consequent impacts on the ecosystem as a whole –resulting in risks of extinction and restrictions of their ecological functions.

Although cats and dogs predominated as pets in the study area, the residual culture trait of keeping wild native animals is still widely disseminated. A large percentage of the wild species kept as pets are captured in their natural habitat, sustaining their clandestine commercialization in the region. The illegal keeping and commercialization of wild animals have cascading effects on the species themselves and their ecosystems of origin. In the case of the semiarid region of Brazil, the impacts of animal capture for the pet market are principally directed toward the avifauna – making it necessary to consider this factor when designing conservation plans for birds inhabiting the Caatinga (dryland) ecosystem. Although other vertebrates are caught and used as pets, this activity does not have as large an impact on mammals and reptiles as they are less frequently sought after for that purpose.

It should be emphasized that in the surveyed area we found exotic birds kept legally as pets (n=4 species) (Appendix 1), which may lead to conservation concerns when such birds escape to the wild and interfere with local ecosystems. Introduced species are one of the principal threats to global biodiversity, due to competition for food resources and territory, and the introduction of previously unknown diseases and parasites [44, 45]. In Brazil, this problem is intensified by poorly planned releases of birds that have been confiscated by the authorities [9]. Even wild species captured illegally can be introduced in inappropriate places (outside of their natural geographical distribution) without proper assessment of their health status, which results in unknown side effects [46]. According to Marini and Garcia [46], a large proportion of the specimens captured illegally are liberated in localities far from their natural geographic distribution and without appropriate evaluations of their state of health. Kuhnena and Kanaanb [39] highlighted that released animals may not be fit to live in the wild on their own, or may impact the natural local populations by introducing diseases or becoming nuisance animals.

The need to incorporate human dimensions in conservation and management of natural resources has been increasingly recognized in the literature [8, 47484950–51]. It will be important to take into consideration the social, economic, and cultural aspects of the local human populations when designing conservation plans to preserve the native wild fauna of the semiarid region of Brazil, as the uses of wild animals and their products are common and widely disseminated in the region. The clandestine perpetuation of these practices, even after many decades of legal prohibition, points to the inefficiency of environmental enforcement actions. To help remedy this situation, educational activities should be promoted in schools, together with the production of informative pamphlets. Stricter and more rigorous measures for combating the illegal traffic in wild animals must be implemented, and in a much wider context, the conservation of the Caatinga biome must be promoted, as it has suffered considerably due to intense anthropogenic impacts in recent decades.