A new endemic lineage of the Andean frog genus Telmatobius (Anura,Telmatobiidae) from the western slopes of the central Andes

The amphibian genus Telmatobius is a diverse group of species that inhabits the Andes. This study analysed the phylogenetic relationships of 19 species described from the central Andes of Chile and Bolivia, and 12 undescribed populations of Chile. A molecular phylogeny based on mitochondrial DNA 16S and cytochrome b shows that the Chilean species belong to three groups: (1) the Telmatobius marmoratus group, widespread in the Chilean and Bolivian Altiplano; (2) the Telmatobius hintoni group, including the species Telmatobius philippii, Telmatobius fronteriensis, and Telmatobius huayra, occurring in the south‐western Altiplano of Chile and Bolivia, and (3) the Telmatobius zapahuirensis group, a new clade which also includes Telmatobius chusmisensis, Telmatobius dankoi, and Telmatobius vilamensis, restricted to western slopes of the Andes, and which was recovered as more closely related to the T. hintoni group than the T. marmoratus group. The divergence times between clades were traced to the late Pleistocene. The molecular phylogeny also confirmed that the groups of the Altiplano and western Andes slopes form a clade separated from the species that inhabit the eastern Andes (Telmatobius verrucosus and Telmatobius bolivianus groups), supporting the forest origin of the Altiplano groups proposed by several previous authors. © 2014 The Linnean Society of London     

Unvarying diet of a Neotropical desert marsupial inhabiting a variable environment: the case of <Emphasis Type="Italic">Thylamys pallidior</Emphasis>

Studies on the diet and other aspects of the natural history of Neotropical marsupials have focused mainly on a few species from tropical and forest habitats. Research on desert marsupials, on the other hand, is almost absent outside Australia. The desert mouse opossum, Thylamys pallidior, is a small marsupial which inhabits the arid lands of Argentina, Chile, Bolivia, and Peru. In Argentina, it occurs in the Monte desert, a highly seasonal system with a heterogeneous landscape which affords a good opportunity to perform comparisons among different environmental situations. We analyzed fecal samples from 123 individuals and compared their diet among different seasons, habitat types, sexes, and ages. The diet of T. pallidior was composed of 68.7% of arthropods and 31.3% of plant material, mainly leaves (24.6%). We found no significant differences in the proportions of any main food category consumed for any of the factors analyzed. Consumption of both plant and animal material seems to be important in the diet of T. pallidior which manages to keep their proportions constant despite the strong variability and seasonality of the habitat. Contrary to most didelphid species, but similarly to most mammals of this area, leaves seem to represent an important source of food possibly because of their abundance and stability in the Monte desert. This represents the first study to focus on the diet of a Thylamys species inhabiting an arid environment.     

Latitudinal variation in diet and patterns of human interaction in the marine otter

The marine otter (Lontra felina) inhabits patches of rocky coastline from central Peru to southern Chile and is classified as Endangered by the IUCN. Given the limited information available about the species, we set out to assess marine otter diet with a view to detecting latitudinal differences, and to assess marine otter activity budgets and interspecific interactions (including anthropogenic) at Peruvian fishing villages and to compare results with similar Chilean studies. Nine study sites from central Chile to southern Peru were sampled for otter spraints to assess relative frequency of prey types and two fishing ports in southern Peru were monitored through focal and scan observations to assess activity patterns, interspecific interactions, habitat use patterns, and dive durations. Results indicate that toward the northern part of its range, crustaceans become less important and fish more important in the diet. Interactions were observed between marine otters and other species, including stray dogs and cats. The strong dependence of marine otters on the availability of safe rocky shelters, and the species’ apparent tolerance to living alongside humans raise conservation concerns about vulnerability to anthropogenic threats. These factors, if not correctly managed, could turn some of these rocky seashore patches into population sinks.     

Seasonal diet by a generalist raptor: the case of the variable hawk (Geranoaetus polyosoma) at Atacama Desert,northern Chile

We determined the seasonal diet of the variable hawk, Geranoaetus polyosoma, in a hyperarid and threatened habitat in the Atacama Desert, northern Chile, by analysing the contents of the bird's pellets. We estimated the biomass and number of individuals of each prey species consumed. We compared our results with those of other studies on G. polyosoma in South America. In general, the diet was characterised by extremely low number of prey, low diversity of species consumed and high dietary breadth. In contrast with other biomes of Chile, in our study reptiles formed the dominant food item and accounted for the highest percentage of biomass consumed from autumn to spring, with rodents being a seasonally significant major food item. Arthropods were also consumed, but the biomass ingested was negligible. Statistically significant differences were noted across seasons in the prey items consumed, reflecting a flexible and opportunistic response to the scarcity of prey available. Our findings add to the data present on the basic natural history of G. polyosoma and can aid in its conservation in the Atacama Desert.     

Predation upon reptiles in Mediterranean habitats of Chile,Spain and California: A comparative analysis

Summary Pradation on reptiles at three Mediterranean-type habitat sites was assessed by computing the incidence of reptiles as a percentage of vertebrates in the diet of each predator species and the incidence of each reptile species as prey for the entire assemblage of predators at each locality. The overall importance of reptiles is lowest in Chile, intermediate in California, and highest in Spain. These differences do not appear to result from interlocality variation in the size distributions of predators or of prey. The incidence of particular reptile species as prey is correlated with their relative abundances in Spain and California, but not in Chile. Behavioral and morphological attributes evidently make some species more vulnerable to predation and others less so than their abundances would predict. Predation on the speciose lizard genus Liolaemus in Chile is sufficient to promote behavioral responses but not major morphological divergence.     

Chromosomal structure of populations of drosophila flavopilosa studied in larvae collected in their natural breeding sites

Summary D. flavopilosa Frey, is a neotropical species of Drosophila living in Chile that, together with 13 other species, has been included by Wheeler, Takada und Brncic (1962) in the flavopilosa species group. Despite the fact that it has not been possible to breed this species in the laboratory, the circumstance that its habitat is well known, has allowed the study of the chromosomal structure of some natural populations of this species, analyzing larvae directly taken to the laboratory from their natural breeding sites: the flowers of the solanacean Cestrum parqui L'Héritier.The present paper describes the mitetic and salivary gland chromosomes of D. flavopilosa, and gives a composite map of the Standard gene arrangement. In central Chile, natural populations of this species are polymorphic with respect to the gene orders in their chromosomes, due to the presence of four independent inversions, all located in one of the six chromosomes (the right arm of the V-chromosome). Quantitative data on the distribution of the inversions shows that there is an altitudinal gradient in the frequencies of two of the four inversions. Heterozygotes for Inversion A, are more frequent at high altitudes than at sea level. On the contrary, heterozygotes for inversion B, are abundant at sea level, but practically disappear at high altitudes. These altitudinal clines have been observed in two valleys near Santiago, Chile, which run from the Andes mountains to the Pacific coast.The work reported in this article has been carried out under Contract AT (30-1) 2465 US Atomic Energy Commission, and partially supported by Grants from the University of Chile, Faculty of Medicine and the Rockefeller Foundation under a joint program.     

Plant foods consumed by Pan: Exploring the variation of nutritional ecology across Africa

It has been shown that differences in resource density and nutrient supply affect variation in ranging patterns, habitat use, and sociality. Among nonhuman primates, chimpanzees (Pan troglodytes) and bonobos (P. paniscus) have often been used as models for the link between social system and habitat ecology. Field reports suggest that resource density is higher in habitats occupied by bonobos (compared to chimpanzee habitats), and in the West (compared to the East) of the range of chimpanzees. In this study we compared diet quality at the level of species and populations using information from nutritional analyses of fruit and leaves consumed by chimpanzees (three) and bonobos (one population). Quality of plant foods was assessed on the basis of a) the concentration of macronutrients, fiber, and anti‐feedants, and b) associations of different nutrient components. Overall plant samples collected at each site differed in terms of macronutrient content. However, nutritious quality and gross energy content of food samples were similar suggesting that dietary quality reflects selectivity rather than habitat ecology. The quality of plant foods consumed by bonobos was within the range of chimpanzees and the quality of plant foods consumed by western chimpanzees was not higher than that of eastern chimpanzees. While the results showed significant variation across forests inhabited by Pan, they did not match with geographical patterns between and within Pan species as proposed in previous studies. This suggests that the nutritional quality of the habitat is not always a reliable predictor of the quality of the diet. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.     

Influence of within‐patch habitat quality on high‐Andean Polylepis bird abundance

Habitat restoration strategies for fragmented high Andean forest landscapes must consider the influence of within‐patch habitat quality on bird abundance. I examined vegetation and bird abundance at three locations within a highly fragmented Polylepis forest landscape in the Cordillera Vilcanota, southern Peru. Across the landscape, there was significant variation in the vegetation structure of Polylepis forest patches of different size categories, especially in terms of tree girth, tree height, tree density, and canopy vegetation structure. Principal Component Analysis extracted five factors of habitat quality, which together accounted for 74.2% of the variability within 15 habitat variables. Polylepis bird species differed in their responses to habitat quality but, overall, variation in Polylepis bird abundance was not fully captured by the range of habitat quality variables. Tall, dense vegetation cover was clearly important for 11 conservation‐important species, a high density of large trees was important for 10 species and primary forest ground cover was important for eight species. Habitat quality exhibited no significant influence on the abundance of only one species –Asthenes urubambensis. The abundance of seven species was associated with lower elevation forest, but only one species was associated with higher elevation forest. Management of habitat quality in large and medium remnant forest patches throughout the Cordillera Vilcanota, particularly in the 3800–4200 m elevation range, will be a cornerstone in ensuring the persistence of the majority of conservation‐important bird species populations.     

The guild structure of a community of predatory vertebrates in central Chile

Summary The trophic ecology of eleven predator species (Falconiforms: Buteo polyosoma, Elanus leucurus, Falco sparverius, Geranoaetus melanoleucus, Parabuteo unicinctus; Strigiforms: Athene cunicularia, Bubo virginianus, Tyto alba; Carnivores: Dusicyon culpaeus; Snakes: Philodryas chamissonis, Tachymenis peruviana) in two nearby localities of central Chile is analyzed. The localities exhibit the typical climate (hot-dry summers, coldrainy winters), and vegetation (chaparral), of mediterranean ecosystems. Densities of the staple prey (small mammals) were estimated by seasonal trapping during two years in both open and dense patches of chaparral.The trophic parameters examined are: 1) proportion of diurnal, crepuscular, or nocturnal prey found in the predators' diet; 2) relationship between abundance of different mammalian prey in the predators' diet, and in both open and densely vegetated habitat patches; 3) mean weight and variance of weight of small mammal prey consumed; 4) average weight of the predators; 5) food-niche breadth of the predators; 6) relationship between average weight of predators and mean weight of mammalian prey taken, its variance, and food-niche breadth; 7) overlap in food-niche between all the predator species; 8) guild packing of the predators. Parameters 1) and 2) are used to assess the importance of temporal and habitat segregation of the predators, respectively; parameters 3), 4), 5), and 6) provide information on the possibilities of partitioning the prey resources among the predators; parameters 1), 2), 7) and 8) are used to investigate the organization of the community in terms of guilds.Three niche dimensions seem to be important in determining the structure of the predator community: 1) hunting activity period (diurno-crepuscular, nocturno-crepuscular), 2) hunting habitat (open, or both open and dense patches), and 3) mean prey size taken. Segregation along these three axes results in generally low food niche overlaps (<54% in 47 of the 55 pairwise comparisons) among the predators, but it is not possible to determine whether this was produced by competitive interactions or stochastic differences. Three guilds (niche overlap >90% in pair-wise comparisons) can be recognized: a) the carnivorous-insectivorous guild formed by the diurnal raptors A. cunicularia and F. sparverius, which tend to hunt in open habitat patches; b) the herpetophagous guild formed by the diurnal snakes P. chamissonis and T. peruviana, which presumably hunt in open habitat patches; c) the carnivorous guild (highly specialized in the capture of two rodent species) formed by the diurnal raptors B. polyosoma, G. melanoleucus, P. unicinctus, and the carnivore D. culpaeus, which hunt in open habitat patches. The diurnal raptor E. leucurus is not clearly associated with any guild, and the only two nocturnal raptors in the community (B. virginianus and T. alba) exhibit marked differences in their trophic ecology.     

Habitat selection of three chrysomelid species associated with Rumex spp.

Summary Habitat selection of three chrysomelid beetles feeding on the Rumex plants was studied in relation to the ecological requirements of the three species and the habitat characteristics arising in their unstable and often unpredictable environment. The different ecological requirements and bionomic characteristics of the three chrysomelids were associated not only with their differing degrees of feeding specialization; they also influenced habitat selection. For example, the small body size and lower food demands of Mantura clavareaui, which is a feeding specialist, allowed it to exploit any habitat, irrespective of habitat size and duration. The other specialist, Gastrophysa atrocyanea, selected larger habitats because of the relatively brief lifespan of its adults after overwintering, its reduced mortality, and greater food demand. On the other hand, Galerucella vittaticollis, which is a multivoltine, general feeder, selected the habitat that lasted longer, rather than one that was larger. This species' life cycle is not synchronized with Rumex phenology, but its adults are long-lived and it has a flexible life cycle. The different patterns in habitat selection among these three chrysomelids prevented serious overlapping of their habitats; thus, the habitat overlapping of 2 or 3 species was 34.62%, that of all 3 species 3.85%. Most of the habitats utilized by Gastrophysa, however, overlapped those of the other two species, because Gastrophysa's habitat utilization range was the narrowest of the three. In Mantura, the degree of overlap with the other two species was lowest because this beetle had the broadest range of habitat utilization. On the other hand, Galerucella adjusted the temporal, rather than the spatial coordinates of its habitat usage when it occupied habitats where the other two specialists were also present. Galerucella, unlike the other two species, is multivoltine. Consequently, it was able to coexist in habitats occupied by the others by exploiting the host plants at times when the other species were numerically few, or even absent. No direct interspecific competition among adults of the three species was observed. Their different patterns of habitat selection created by their different responses to available food allowed them to coexist on Rumex without direct competition.     

Long‐term monitoring of tropical alpine habitat change,Andean anurans,and chytrid fungus in the Cordillera Vilcanota,Peru: Results from a decade of study

The Cordillera Vilcanota in southern Peru is the second largest glacierized range in the tropics and home to one of the largest high‐alpine lakes, Sibinacocha (4,860 m). Here, Telmatobius marmoratus (marbled water frog), Rhinella spinulosa (Andean toad), and Pleurodema marmoratum (marbled four‐eyed frog) have expanded their range vertically within the past century to inhabit newly formed ponds created by ongoing deglaciation. These anuran populations, geographically among the highest (5,200–5,400 m) recorded globally, are being impacted by the chytrid fungus Batrachochytrium dendrobatidis (Bd), and the disease it causes, chytridiomycosis. In this study, we report results from over a decade of monitoring these three anuran species, their habitat, and Bd infection status. Our observations reveal dynamic changes in habitat including ongoing rapid deglaciation (18.4 m/year widening of a corridor between retreating glaciers from 2005 to 2015), new pond formation, changes in vegetation in amphibian habitat, and widespread occurrence of Bd in amphibians in seven sites. Three of these sites have tested positive for Bd over a 9‐ to 12‐year period. In addition, we observed a widespread reduction in T. marmoratus encounters in the Vilcanota in 2008, 2009, and 2012, while encounters increased in 2013 and 2015. Despite the rapid and dynamic changes in habitat under a warming climate, continued presence of Bd in the environment for over a decade, and a reduction in one of three anuran species, we document that these anurans continue to breed and survive in this high Andean environment. High variability in anuran encounters across sites and plasticity in these populations across habitats, sites, and years are all factors that could favor repopulation postdecline. Preserving the connectivity of wetlands in the Cordillera Vilcanota is therefore essential in ensuring that anurans continue to breed and adapt as climate change continues to reshape the environment.     

A comparison between vegetation and diet records from the wet and dry season in the cottontail rabbitSylvilagus floridanus at Ixtacuixtla, central Mexico

Mexico has eight endemic lagomorph species, several of which are endangered. For conservation reasons it is necessary to know more about their diet. In a first step we applied the method of fecal pellet analysis to the cottontailSylvilagus floridanus (Allen, 1890). Since it is common in Mexico, information on its diet should provide a useful baseline with which to compare the diets of other Mexican lagomorphs. At Ixtacuixtla, we recorded vegetation and analyzed fecal pellet content once in August (wet season) and once in March (dry season) at 4 sampling sites representing different habitat types. The comparison of vegetation and diet records suggestedS. floridanus to occupy the same dietary niche in the different habitats. Measures of niche breadth showedS. floridanus to be neither a generalist nor a specialist. Nevertheless, it appeared to be quite selective in consuming particular herb and grass species even when they became scarce during the dry season. Since the vegetation record only poorly represented the rabbits’ diet, a more focused approach is suggested for future studies: first, to identify the relevant food species in the diet, second, to obtain data on the availability of these, and third, to concentrate on time points when changes in resource state could be a limiting factor.     

Habitat preference in the critically endangered yellow‐tailed woolly monkey (Lagothrix flavicauda) at La Esperanza,Peru

Habitat loss is one of the main threats to wildlife. Therefore, knowledge of habitat use and preference is essential for the design of conservation strategies and identification of priority sites for the protection of endangered species. The yellow‐tailed woolly monkey (Lagothrix flavicauda Humboldt, 1812), categorized as Critically Endangered on the IUCN Red List, is endemic to montane forests in northern Peru where its habitat is greatly threatened. We assessed how habitat use and preference in L. flavicauda are linked to forest structure and composition. The study took place near La Esperanza, in the Amazonas region, Peru. Our objective was to identify characteristics of habitat most utilized by L. flavicauda to provide information that will be useful for the selection of priority sites for conservation measures. Using presence records collected from May 2013 to February 2014 for one group of L. flavicauda, we classified the study site into three different use zones: low‐use, medium‐use, and high‐use. We assessed forest structure and composition for all use zones using 0.1 ha Gentry vegetation transects. Results show high levels of variation in plant species composition across the three use zones. Plants used as food resources had considerably greater density, dominance, and ecological importance in high‐use zones. High‐use zones presented similar structure to medium‐ and low‐use zones; thus it remains difficult to assess the influence of forest structure on habitat preference. We recommend focusing conservation efforts on areas with a similar floristic composition to the high‐use zones recorded in this study and suggest utilizing key alimentation species for reforestation efforts.     

New evidence of unexpectedly high animal density and diet diversity will benefit the conservation of the Critically Endangered western ringtail possum

A comprehensive and contemporary understanding of habitat and resource requirements has been critical to the conservation of multiple taxa and ecosystems globally. Until recently, much of the ecological knowledge that contributes to conservation priorities and strategies for the Critically Endangered western ringtail possum (Pseudocheirus occidentalis) was largely derived from decades‐old observations in peppermint (Agonis flexuosa) and marri‐jarrah (Corymbia calophylla and Eucalyptus marginanta) woodlands in the northern parts of the species range. These observations do not account for more recent evidence of their flexible use of habitat resources in other regions of its range. This may represent a significant conservation opportunity for the species through the identification of additional habitats that warrant protection. In a region where knowledge of their ecology is scarce, we used scat analysis and quantitative spotlighting to determine the diet and density of western ringtail possums in three vegetation types: peppermint, sheoak (Allocasuarina fraseriana) and marri‐eucalypt (C. calophylla, E. marginanta and Eucalyptus staerii) woodlands. Given the species’ reported dependence on peppermint woodlands and dominant canopy species for food sources, we hypothesised that western ringtail possums would be most abundant in this habitat type and that their diet would comprise the foliage of few (≤2 species) canopy species. We found western ringtail possums consumed a higher diversity of plant species than expected (8–14), exhibited dietary preference for non‐dominant canopy species and were present in all sampled vegetation types at substantially higher densities than previously recorded for the region (as high as 17 possums ha^?1). Our results confirm (i) the western ringtail possum is flexible in its use of habitat resources and (ii) the significant conservation value of sheoak and marri‐eucalypt woodlands in the southernmost portion of its distribution.     

Habitat or prey specialization in predatory ladybird beetles: a case study of two closely related species

This study examines the niche and diet breadth of two closely related sympatric aphidophagous ladybirds: Adalia decempunctata and A. bipunctata. The degree of habitat specialization of these species is investigated, and its effect on life history traits of females is explored. The importance of prey quality in determining the diet breadth is also examined. The niches occupied by these species in three countries, the UK, Belgium and southern France, are similar: A. decempunctata is an arboreal habitat specialist with a narrower set of prey than A. bipunctata, which is commonly found on several types of vegetation. The niches of the two species overlap on trees. Experiments indicate that habitat specialization has resulted in A. decempunctata investing more in each of its offspring than A. bipunctata. A. decempunctata females lay, relative to their body size, heavier eggs than those of the more generalist A. bipunctata, which results in A. decempunctata having bigger larvae. In addition, A. decempunctata larvae are better at surviving starvation than A. bipunctata larvae. In contrast to the expected pattern in food specialization, our study failed to demonstrate a better efficiency of the specialist when fed its usual prey and a detrimental effect when fed on prey that it is unlikely to encounter in the field. The reproductive performance of the specialist ladybird was better when fed an aphid that it was unlikely to regularly feed on in the field. Therefore, the narrow diet of the specialist ladybird is most likely a consequence of it occupying a narrow habitat rather than the quality of the prey. Although further studies on specialization in predatory insects are needed, the results indicate that unlike the role of plant quality in host specialization in herbivorous insects, prey quality has not been the main determinant of ecological specialization in these predatory insects.     

Isodars unveil asymmetric effects on habitat use caused by competition between two endangered species

In order for competing species to coexist, segregation on some ecological niche component is required and is often mediated by differential habitat use. When unequal competitors are involved, the dominant species tends to displace the subordinate one to its less preferred habitat. Here, we use habitat isodars, an approach which reflects evolutionary stable strategies of habitat selection, to evaluate whether interspecific competition between two competing species with distinct habitat preferences, the little bustard Tetrax tetrax and the great bustard Otis tarda, modulates their habitat use. Field data on these endangered species demonstrate that unequal competitors can coexist without completely segregating on their preferred habitats. The negatively sloped isodar of the subordinate little bustard unveils its competition with the dominant great bustard. Interference from great bustards in secondary cereal habitats reinforces use of preferred natural habitat by little bustards. Studies of density‐dependent habitat selection by a single‐species can thus aid in identifying the effects of competition on community composition, and guide the conservation of at‐risk species. Isodars, in particular, represent a promising method to gain clear knowledge on interspecific competition for species in which experimental manipulations are not feasible.     

Distance to suburban/wildland border interacts with habitat type for structuring exotic plant communities in a natural area surrounding a metropolitan area in central Chile

Background: The explosive growth of urbanisation in Mediterranean ecosystems in Chile has favoured the rapid expansion of exotic plant species, yet factors driving these invasion patterns in adjacent natural areas remain poorly assessed.

Aims: To assess how distance to a suburban/wildland border, habitat type, site-scale disturbance and woody plant cover of native species influences the diversity of exotic species in a natural area surrounding the city of Santiago, Chile.

Methods: Three watersheds were chosen, and the diversity of exotic species was assessed in 36 100-m-long transects, equally distributed over two distance categories and three habitats. For each transect, we measured woody plant cover of native species and frequency of rabbit faeces as a measure of competitive exclusion and site-scale disturbance, respectively.

Results: Species diversity decreased as the distance from the suburban/wildland border increased, and it was found to be higher in north-facing habitats compared to south-facing and alluvial habitats. Neither native woody plant cover nor frequency of rabbit faeces had an effect on species diversity.

Conclusions: The current pattern of exotic plant species in this natural area is mainly influenced by the distance to suburban border and habitat type. An adequate management of conditions favouring exotic species in suburban/wildland border may prevent the spread of these into natural areas next to urban settings.     

Food of the zebra finch (Poephila guttata), and an examination of granivory in birds of the Australian arid zone

Birds are important granivores in the Australian arid zone, and this paper reviews their role by assembling available data on diet and habitat selection of the granivorous species occurring in the region. Paucity of dietary information is alleviated by a study of the food of the zebra finch (Poephila guttata) at two sites in the eastern arid zone. Zebra finches subsisted entirely on grass seeds of a relatively narrow specific range; 17 classes of seeds (at least 19 species) were eaten, but one class dominated the diet at each study site and only five classes (probably six species) were significant overall. Comparative information concerning granivorous species- suggested that the seeds of grasses and shrubs are of most importance in diets, that larger species tended to eat larger seeds from a wider variety of plants because of the addition of shrub species to the diet, and that Acacia shrublands contained most species. Characteristics of the arid zone that are of particular importance to granivorous birds appear to be the abundance of grasses and the patchy and erratic nature of the rainfall.