Ethological studies of native Mexican mammals: A review

The number of ethological studies based on Mexican mammals have increased in recent years compared to those from other Latin American countries. This study conducts an analytical review of the literature on ethological studies of native Mexican mammals. Specialized publications and electronic bibliographic databases were thoroughly searched to identify ethological studies of Mexican mammals published in scientific journals between 1900 and 2018. Information on the collection locality, state, first author nationality, country of origin of the journal, and taxa studied were recorded for each article. The articles were then classified into the 12 major ethological fields, and their data were grouped and summarized in five-year periods, and a map showing the geographic distribution of the studied localities was built using QGIS. A total of 160 studies were identified; three distinct periods could be recognized: the first (1900 to 1953) with a lack of publications, the second (1954 to1995) with low production (n = 16), and the third (1996 to 2018) with a notable increase in published articles (n = 144); in general, there was a greater participation of Mexican authors (67.5 %). Most studies (> 70 %) focused on primates, rodents, bats, and carnivores. Veracruz is the entity with the most articles, while foraging, movement, nesting, rearing, and territorial behavior were the subjects most studied, followed by social behavior, cooperation, and kinship. The greater number of studies published in the past two decades is likely the result of an increased number of mammologists and their engagement in national and international collaborative partnerships, mainly in areas such as ecology and taxonomy. Despite a relatively recent development of the field in Mexico, an absence of studies on half of all terrestrial mammals orders, and few studies throughout northern parts of the country, mammalian ethology in Mexico has already made significant contributions and is highly likely to continue its development and consolidation.

Mammals of the Natural National Park Selva de Florencia, Caldas, Colombia

The Department of Caldas, Central Andes of Colombia, has two National Natural Parks protecting strategic Andean ecosystems. However, the available information on mammals in these protected areas has not been compiled or updated recently. Here, we present an updated inventory of the mammals present in the Selva de Florencia National Natural Park. To construct the inventory, we used historical (museum vouchers) and recent records obtained during field activities over the last 20 years. We used several trapping methods including Sherman and Tomahawk traps, mist nets, and camera traps. We documented 81 mammal species belonging to nine orders, 25 families and 59 genera. Bats (Chiroptera: 30 spp.), rodents (Rodentia: 17 spp.), and carnivores (Carnivora: 13 spp.) were the most diverse groups, representing 73.2 % of recorded species. We also recorded orders such as Didelphimorphia (8 species), Primates (5), Pilosa (3), Artiodactyla (2), Cingulata (2), and Eulipotyphla (1). Also, we recorded two endemic species (Marmosops chucha and Cryptotis colombianus) and two new species for the Department of Caldas (Bassaricyon neblina and Heteromys aff. anomalus). These species constitute elements of the Andean region and the Nor-Andean and Chocó-Magdalena biogeographic provinces. We highlight the presence of four endangered primates (Aotus lemurinus, Ateles hybridus, Cebus versicolor, and Saguinus leucopus), two of which are endemic to Colombia: S. leucopus and C. versicolor. This work is the baseline to update the management plan of the protected area, from the review of its conservation targets, the definition of the specific management goals, to its effective monitoring.

Use of mineral licks by mammals in areas of the Amazonia with no hunting pressure

Mineral licks are areas where several species of animals, including mammals, converge to consume water and soil as a mineral supplement. Certain mammal species are an important source of protein in the diet of indigenous communities. Many of these species are under hunting pressure and their populations have been seriously affected. The purpose of this study was to determine the species of large and medium-sized mammals that use three open mineral licks in the area of the Kichwa Añangu community, within the Yasuní National Park, where hunting used to take place. We calculate the capture frequency for the visiting species and the richness, composition, and similarity of the assemblages recorded in the mineral licks during two climatic seasons of the year (higher rainfall vs. lower rainfall). We installed a single camera trap station (CTS) at each mineral lick during three sampling periods in 2018. In each period, all cameras operated 24 hours a day for 30 to 40 days and were set to capture three photographs upon sensor activation, with 60-second intervals between consecutive activations. With a total sampling effort of 249 days/trap, we obtained 645 photographs and 398 grouped records of 16 species. We recorded 95.2 % of the expected richness according to the Chao1 estimator (S = 16.8). The species with the highest capture frequency were: Mazama zamora (FC = 62.2), Tayassu pecari (FC = 35.7), Tapirus terrestris (FC = 28.9), and Pecari tajacu (FC = 8.0). ECT-1 and ECT-2 captured 11 species each, and ECT-3 captured nine species. There were no significant differences in the species composition between the three mineral licks or between climatic seasons. Our results show that the focal mineral licks studied attract a rich mammalian fauna, which likely points to the success of the government regulation of wildlife trafficking and the application of sustainable tourism practices in the Añangu community.

Identification keys to murid rodents of Argentina

Muroid rodents are the most species-rich superfamily of rodents occurring in Argentina. Increased fieldwork with these mammals depicts the need of adequate keys to identify species on the base of external characters. In this contribution we provide three keys (one for families and subfamilies, and another two for Sigmodontinae and Muridae, respectively) for all known species of Cricetidae and Muridae distributed in Argentina (42 genera and 110 species). In addition to the dichotomous keys, and as a way to facilitate the identification, we include for each species a brief description of its distribution and the main habitats where it occurs.

Mitochondrial DNA indicate paraphyletic relationships and resolve disjunct distributions in the Neotoma mexicana species group

Woodrats (genus Neotoma) comprise 24 species found primarily in the US and Mexico. The Neotoma mexicana species group reaches its southernmost distribution in the highlands of southern Mexico and Central America. Previous research suggested that N. mexicana has a disjunct distribution, and it, N. ferruginea and N. picta have allopatric distributions and limit each other around the lowlands of the Isthmus of Tehuantepec. However, these hypotheses were suggested with incomplete subspecific sampling near the isthmus. We used new samples of N. m. parvidens from the Oaxacan Sierra Madre del Sur and N. m. tropicalis from the Sierra Norte de Oaxaca to assess their taxonomic affinity. With new sequences of the mitochondrial cytochrome-b gene, we found that both subspecies belong to N. ferruginea, not N. mexicana. We therefore suggest that N. mexicana is continuously distributed from the US to the Transmexican Volcanic Belt, N. picta inhabits the Guerreran Sierra Madre del Sur, and N. ferruginea ranges from the Oaxacan Sierra Madre del Sur to Central America. Our findings indicate that the Isthmus of Tehuantepec did not promote speciation in these woodrats, but we did detect intraspecific genetic differentiation between samples of N. ferruginea from east and west of the isthmus.

Use of distribution models in the conservation of a Mexican endemic lagomorph

The volcano rabbit (Romerolagus diazi), endemic to the central-eastern Transmexican Volcanic Belt, is one of the most threatened lagomorphs worldwide. Several factors threaten to decrease its geographical distribution, which is already restricted to the Pelado, Tláloc, Iztaccíhuatl, and Popocatépetl volcanoes. Our study aimed to propose priority areas for the conservation of this rabbit within Iztaccíhuatl-Popocatépetl National Park (IPNP) based on species distribution models. Volcano rabbit presence data were collected through different field sampling techniques and public and private databases. The environmental predictors used to model suitability were obtained from both open-access remote sensors and topographic information. The models’ performance was adjusted by evaluating different sets of variables and data to improve the certainty of the results. We obtained an area of 132.5 km2 within the IPNP potentially occupied by the volcano rabbit and a high suitability area of 7 km2. In addition, four priority conservation polygons for the volcano rabbit were identified within the National Park. We showed that the suitability and potential distribution are not uniform in the park, being the alpine meadow dominated by Muhlenbergia sp., the most suitable area for R. diazi. Therefore, the conservation strategies should focus on preserving these meadows in the prioritized polygons, avoiding tourist and unskilled personnel’s access. This work represents a contribution to the conservation of the volcano rabbit and a theoretical and practical tool for use in the IPNP.

The Big Naked-backed Bat, Pteronotus gymnonotus, Chiroptera, Mormoopidae, in its northernmost geographic distribution range

The Big Naked-backed Bat, Pteronotus gymnonotus, is one of the 15 species currently recognized of this genus, with relatively few specimens in scientific collections, besides being poorly studied. It has a geographical distribution spanning from México through Central America and reaching Perú and Brazil, in which it occupies a variety of habitats from desert to tropical forests below 400 meters above sea level. Here, we report the records that demonstrate its presence, and data about its natural history in southeastern México, the northernmost part of its geographic distribution range. Between June 2002 and July 2018, we captured specimens in 44 bat roosts located in southeastern México, including the Parque Estatal Agua Blanca, Macuspana, Tabasco; Grutas de Martínez de la Torre, Matías Romero Avendaño, Oaxaca; and in Cueva de Villa Luz, Tapijulapa, Tabasco. In the three locations mentioned, we recorded the occurrence of P. gymnonotus individuals, whose taxonomic identification at species level was corroborated by both morphological data and genetic analyses. Previously, the only records of P. gymnonotus in México were from only four specimens scattered across time, so these new recorded locations confirm the presence of this species in the country. In addition to this, in Agua Blanca State Park and Villa Luz Cave we found a reproductive resident population. The record from Grutas de Martínez de la Torre is located in the middle of the Tehuantepec Isthmus, a well known biogeographical barrier for many taxa in the transitional area to the Pacific lowland’s region. We suggest that the occurrence of P. gymnonotus in México is also associated with large remnants of evergreen and gallery forests, located in the lowland areas along the Gulf of México and in the north and east of the Tehuantepec Isthmus.

Relationship between age-sex classes and prevalence of Giardia spp. and Blastocistys spp. in black and gold howler monkeys inhabiting fragmented forests

Studies have shown that as age increases, parasitism could also be more frequent, on the other hand, the lack of immunity can increase the risk of infection in younger individuals. Regarding sex, there is a general tendency for males to be more parasitized than females, in the case of primates, this is related to the effort made by males into attaining and maintain a high rank, implying high levels of testosterone, a hormone with immunosuppressive effects. Immunosuppressive effects of stress hormones can also increase susceptibility in dominant or subordinate individuals, nevertheless, in a study, the level of exposure to parasites seems to be more important than the immunosuppressive effects of stress in explaining why dominant females have more infections from directly transmitted parasites. In this study, we investigated the relationship between the prevalence of Giardia spp. and Blastocystis spp. and the categories of age and sex in black and golden howler monkeys (Alouatta caraya) of Argentina. We analyzed 375 fecal samples from 27 individuals (juveniles and adults of both sexes), using microscopy and techniques of flotation and sedimentation. To analyze the relationship between age, sex, and infection prevalence, a Generalized Linear Mixed Model was used. In adults, the prevalence of infection was 78.5 % while in juveniles, all individuals (100 %) were infected with both protozoa. Males had a infection prevalence 84.6%, in females it was 92.8 %. When comparing infection prevalence between ages and between sexes, no significant differences were found (P > 0.05). Research suggests that parasite infection rates may be influenced by specific form of transmission, in this sense, these protozoa, are transmitted through ingestion of cysts which are infectious immediately after defecation has occurred. On the other hand, all members of the group tend to defecate simultaneously, leaving all the members of the group exposed to infection. Therefore, we suggest that physiological or behavioral factors do not appear to be important in the risk of protozoan infection.

Characterization of assemblages in neotropical cave dwelling bats based on their diet, wing morphology, and flight performance

Bats have a great variety of wing morphologies that determines the bat’s flight performance, and this in turn conditions the forage aerosphere and the food it can obtain. Several studies have shown differences in wing morphology, flight performance, and forage aerospheres among species from different trophic guilds. However, for species that share a guild this is not entirely clear. It is possible that these species have differences in their diet and show changes in wing morphology that modify their flight performance and forage areas. Determining this will allow a better understanding of spatial segregation among species that share a trophic guild. These studies allow the identification of species assemblages based on wing morphological differences and flight performance that would not be distinguished only by guild membership. Our goal was to define the species assemblages that make up a community of Neotropical cave dwelling bats based on their trophic guild, flight performance, and forage zone. A community of Neotropical cave dwelling bats from a cave in Veracruz, Mexico was analyzed. The diet of each species was determined by means of their stomach contents and bibliographic review. In addition, aspect ratio, wing loading and tip index were calculated. Based on the wing characteristics and diet, multivariate groupings and orders were performed, as well as to define the assemblages present. According to the wing characteristics and the dietary composition, four groups of species were found that represent four different flight characteristics in terms of agility and maneuverability. There was agreement between diet and wing characteristics, and the four trophic groups were identified through canonical correspondence analysis. Correlating wing morphology, diet and forage area allows us to adequately define the assemblages of a community of bats. Regarding the hypothesis, it was found that species that share a food guild show differences in the composition of their food and wing morphology, which generate differences in flight performance and forage areas. Four assemblages differing in forage aerospheres among three trophic guilds are described: understory and facultative artrhopodivorous, semi-clearing hematophages, and facultative nectarivores. Finally, spatial segregation between the species of the families Mormoopidae and Natalidae was recognized.

Relative abundance and habitat selection of the montane guinea pig Cavia tschudii in a wetland at coastal desert with comments on its predators

Relative abundance and habitat selection of the montane guinea pig Cavia tschudii in a wetland at coastal desert with comments on its predators