Study área

Between June and August, 2012, six Mayo-Yoreme Ceremonial Centers were visited (Mochicahui, El Ranchito de Mochicahui, Charay, Sibirijoa, Tehueco and Los Capomos) and five indigenous communities (Santa María, Teroque Viejo, Higueras de los Natoches, Jahuara Primero, and La Palma) from the municipality of El Fuerte located between 25° 25’ 12’’ to 25° 55’ 48’’ north, and 108° 30’ 36’’ to 108° 58’ 12’’ west, covering an approximate surface of 2662.43 km² (Figure 1).

Figure 1 Study area. Taken from ^{Cortés-Gregorio et al. (2013)}. 

The altitudinal gradient ranges between 20 m in Valle de El Fuerte, to 1000 in its border with the municipality of Choix, to the northeast. The climate ranges from very dry warm [BW(h’)hw] to semi-dry warm [BS1(h’)hw], with rains distributed between June and September, and droughts between March and May (^{García, 1990}). The mean annual temperature ranges between 24 and 26 °C, and the mean annual precipitation between 300 and 700 mm. The predominant land use in the low parts is irrigationbased agriculture with annual crops, mostly, alternating with some remnant areas of sarcocaulescent shrub, while there are deciduous low forests with some grasslands and rainfed agriculture towards the high parts (^{Cortés Gregorio et al., 2013}). The population that speaks an indigenous language represents 0.5 to 87.0 % and that which resides in indigenous households ranges between 2.6 and 97.9 % of the total. Between 17.3 and 41.4o% of the population of 15 years or more does not have complete primary education, based on the 2010 population and housing census from INEGI. According to the National Population Council (CONAPO), by 2010 the degree of marginalization in six of the 11 localities visited was high; four present medium marginalization and only the indigenous ceremonial center of Mochicahui has low marginalization. The detailed information of the social characterization of the study area is available in ^{Cortés-Gregorio et al., 2013}.

Identification of species and forms of use

Each person interviewed was asked openly about the species they usually hunt, and they could be more than one. Identification of the species was done with support from field guides (^{Reid, 2006}). Of each species that the interviewee recognized exploiting, questions were made regarding the forms of use that they were destined to, and they could choose more than one of the following options: dietary, artisanal, medicinal, taxidermy, control as detrimental fauna, amulet, ritual, as pet (for the case of exploiting live animals), or other uses (which had to be specified). Of the latter option, an interviewee arose who recognized that he used the product of hunting to feed his dog.

Importance value of the species used

In order to estimate the importance value of each species in view of its uses, a database was elaborated per ethnic group where the columns corresponded to the species and the lines to the uses, and in each cell the value corresponding to frequency of mention was assigned. Since it was considered that the importance value of use of each species was dependent on the number of uses and the frequency of its mentions, Shannon’s diversity index was used (Equation 1):

1

where: p _i =n _i / N, S: number of uses mentioned, p _i : proportion of mentions of use i with regards to total mentions, n _i : number of mentions of use i, and N: total number of mentions of use. It was considered that as the index value was higher, the importance of the species of the mammal exploited was higher.

Statistical analysis

To compare the number of species exploited among both ethnic groups, a Mann Whitney nonparametric U test was used for two independent samples, given that the response variable did not have a normal distribution. To analyze the possible differences in the forms of use of hunting between ethnic groups, it was considered to group the species per Order. Contingency tables were used to analyze the possible association between categorical variables through Pearson square Chi tests (X ²). Fisher’s exact stat was used if an expected frequency lower than five was obtained. For multiple responses, the Bonferroni adjustment was used to correct the significance values. In the cases where categorical variables (columns) were contrasted with numerical variables (lines), a t test was used to compare the means, with a significance level of 5 % (^{Díaz de Rada, 2009}).

The Microsoft^® Excel software was used to organize information; for the statistical analysis the IBM^® SPSS software was used, and for the calculation of the Shannon index the PAST^® software (^{Hammer et al., 2009}).

Ethnic group

Of the 76 hunters who exploited at least one species of mammal, 54 % (41) recognized themselves as Mayo-Yoreme and the rest (35) were Yoris.

Species exploited

The exploitation of 16 species was documented, included in 10 families and six orders. Three species are listed in the official norm NOM-059SEMARNAT-2010 and two more in CITES (Convention on the International Commerce of Threatened Species of Wild Fauna and Flora, Convención sobre el Comercio Internacional de Especies Amenazadas de Fauna y Flora Silvestres) (Table 1).

Table 1 Mammal species exploited by hunters from 11 Mayo-Yoreme communities in the municipality of El Fuerte, Sinaloa (with information from ^{Cortés-Gregorio et al., 2013}). 

A: Threatened, Pr: Subject to special protection, Appendix II: Species that are not necessarily threatened to extinction but which could become threatened unless their commerce is strictly controlled

The number of local species exploited by hunter did not vary between both ethnic groups (p>0.05); however, it was found that the Yoreme hunters exploited between one and 11 species of the 15 recorded, with a mean of 4.2±2.2, while the Yoris hunted between one and eight species (mean=4.2±1.6).

No evidence was found about the mention of species exploited being different between both ethnic groups (Fisher statistical exact =10.243, p=0.785). Of the five species of mammals with highest frequency of mentions (Figure 2), ^{Tlapaya and Gallina (2010)} found 16 species of mammals exploited in the coffee plantations of Veracruz, with armadillo and rabbit (Sylvilagus floridanus) standing out as the most frequent.

Figure 2 Frequency of mention per mammal species exploited and ethnic group. 

The species mentioned with highest frequency of mention among Yoremes and Yoris were: Audubon rabbit Sylvilagus audobonii (33 and 32 respectively), antelope jackrabbit Lepus alleni (30 and 29), whitetailed deer Odocoileus virginianus (28 and 29), collared peccary Pecari tajacu (27 and 28) and armadillo Dasypus novemcinctus (22 and 14) (Figure 2).

Uses destined to the hunt

Eight forms of use were identified of local mammals hunted by those interviewed (Figure 3) and each species had one to five. The most frequent ones by Yoremes and Yoris were dietary (61.5 and 64.4o%), artisanal (25.2 and 24.7 %), medicinal (7.3 and 4.1 %) and ritual (4.6 and 4.1 %), and no differences in the uses were found between both ethnic groups (X ²=6.039, gl=8, p=0.643).

Figure 3 Frequency of mention of the uses of wild mammals per ethnic group. 

This coincides with what was documented by ^{González-Bocanegra et al. (2011)} in rural communities of the Humedales de Catazajá, La Libertad, in the state of Chiapas, where three of the most important uses were dietary, medicinal and artisanal.

When grouping the uses per Order that species belong to and taking into consideration the number and frequency of mention, it was identified that at least in the Rodentia order there was a differentiated use between the ethnic groups (Pearson X ²=13.30, gl=4, p=0.01), indicating that the dietary use of the Sonoran woodrat was more frequent among the Yoremes and its medicinal use was exclusive to this ethnic group.

The rest of the orders did not demonstrate that the use and the ethnic group were related (p>0.05), suggesting that the trends of use were quite similar between Yoremes and Yoris. However, it is possible to appreciate that the artisanal and medicinal uses recognized by the Yoreme interviewees were greater for the species of the Carnivora and Xenarthra orders (Figure 4).

Figure 4 Percentage of mention of uses per order and ethnic group. 

The number of uses of the Artiodactyla order (deer and boars) in both ethnic groups was significantly higher than all the rest (p<0.05) and the Xenarthra order (armadillos) was higher than the Lagomorpha order (p<0.05) only for the Yoreme hunters (Table 2).

Table 2 Means comparison in the number of uses between orders within each ethnic group. 

For each significant pair (p£0.05), the key of the lower category appears below that of the category with a higher mean.

Importance value

The species with highest values of the Shannon diversity index for the Yoreme group were the whitetailed deer, the collared peccary and the wildcat, and for the Yoris they were the white-tailed deer, the Sonoran woodrat and the wildcat (Table 3). The case of the woodrat should be observed; although it is true that it is the second species of importance in the case of the Yoris, this result is due to the fact that it had three mentions and three uses, circumstance to which the diversity index used is sensitive, but which contrasts with the case of the Yoremes, where having two uses and 10 mentions resulted in a lower value of the index. The predominantly dietary use, together with the medicinal use of this species, suggests a differentiated form of use between the Yoreme and the Yori.

Table 3 Total uses, mentions and importance value (Shannon Index) per mammal species exploited by ethnic group. 

Al: Dietary, Me: Medicinal, Am: Amulet, Ri: Ritual, Ta: Taxidermy, Co: Control of damaging species, Ar: Artisanal, Ap: Dog food.

The species with the highest number of mentions for dietary use for both ethnic groups was the Audubon rabbit (33 and 32 for Yoremes and Yoris, respectively), agreeing with what was documented by ^{Tlapaya and Gallina (2010)} in the coffee plantations of Veracruz. After the rabbit, the jackrabbit was the most mentioned species for this use (30), followed by the deer, the boar (27 respectively) and the armadillo (22). The Yoris mentioned the deer and the jackrabbit (29, respectively), followed by the boar (28) and the armadillo (14).

The armadillo was the species most frequently used as food in Cañón del Usumacinta, in Tabasco (^{Hernández-López et al., 2013}), while ^{Nahmad et al. (1994)} found that, in addition to this species, the hunters from the Chatino ethnic group in Oaxaca exploited rabbits, deer and boars. A particular case of dietary use recognized by the Yoreme interviewees was that of the Sonoran woodrat. Similar uses in the Neotoma genus have been reported in the Potosino Zacatano Highlands (^{Mellink et al. 1986}; ^{Márquez Olivas, 2002}).

The artisanal use was the most frequently mentioned after the dietary one among both ethnic groups. The deer and the boars were the species mentioned most by the Yoremes (24). Of the white-tailed deer, they used the head as ceremonial headdress for the dancer, whose antlers are decorated with ribbons and flowers of various colors; and their hoofs to compose the “collolis” or “rijju’utiam”, sash or belt of the dancer in the Yoreme language; their legs form the handles of the rattles, made with emptied gourds filled with seeds; and their leather is used to make several types of masks that are representative of the Mayo-Yoreme culture, such as the “judíos” for Easter Week. For the latter, the hides of collared peccary and wildcat were also used.

The medicinal use was the one mentioned more frequently by the Yoremes (19) than by the Yoris (9), with six and three species, respectively. Among the Yoremes, the armadillo was the species with most mentions (8), followed by the white-tailed deer (5). Those interviewed manifest that armadillo fat is used to cure diverse respiratory conditions, such as whooping cough and bronchitis, coinciding with what is stated by Chatino hunters in Oaxaca (^{Nahmad et al., 1994}). Other researchers have documented the medicinal use of the armadillo (^{López-Carrera et al., 2005}; ^{Tlapaya and Gallina, 2010}; ^{Hernández-López et al., 2013}; ^{UNAM, 2009}), particularly that of its fat, to cure cutaneous infections, and of the carapace or concha, which they use to alleviate coughing (^{Ávila Nájera et al., 2011}). Likewise, in the state of Hidalgo the Otomí ethnic group in Valle del Mezquital uses the carapace to prevent whooping cough, hanging a part of it around their children’s neck, together with a piece of acacia root. In Papantla, Veracruz, the Totonacos use a stew of its tail (^{UNAM, 2009}). However, it has been documented that armadillo is, in addition to humans, the only species that can contract leprosy. ^{Truman et al. (2011)} informed that this disease can be passed on to people when they eat its meat, when they have contact with the soil where they build their nests, or by direct contact with the animal, which happens during their hunt, to the degree that ^{SEMARNAT (2012)} has included an internet link about armadillo where they warn about this potential danger.

The Sonoran woodrat (Neotoma phenax) is another species that seems to be related with Chagas disease. This illness is caused by the protozoan parasite Trypanosoma cruzi and is transmitted by hematophagous insects from the Reduviidae family, Triatominae sub-family. Chagas disease is an important cause of death in America, since it has affected 16 to 18 million people and it is estimated that 100 million people from 21 countries live in areas of high prevalence of the disease and, therefore, are at risk of infection (^{Townsed-Peterson et al. 2002}).

Both groups recognize the healing properties of the white-tailed deer and particularly of its blood. Other species, such as the boar, the opossum, the Sonoran woodrat and the skunk, were recognized by those interviewed for their medicinal properties, agreeing with other authors (^{Nahmad et al., 1994}; ^{López-Carrera et al., 2005}; ^{Tlapaya and Gallina, 2010}).

Both the deer and the boars were recognized by both ethnic groups for their ritual uses, linked to the Yoreme ceremonies, and with which the local mestizo population feels identified. As has been established for artisanal use, the making of various elements for Yoreme dances is part of their rites and ceremonies.