Niche overlap and resource partitioning among five sympatric bufonids (Anura, Bufonidae) from northeastern Argentina
01 Jun 2009-Phyllomedusa: Journal of Herpetology (Melopsittacus Publicações Científicas)-Vol. 8, Iss: 1, pp 27-39
TL;DR: Studying the diet behaviors and trophic parameters of sympatric species provides important data for understanding the community and for the development of conservation guidelines.
Abstract: Niche overlap and resource partitioning among five sympatric bufonids (Anura, Bufonidae) from northeastern Argentina. The niche overlap and resource partitioning were analyzed for five sympatric bufonids from Northeastern Argenti- na: Rhinella schneideri, R. bergi, R. fernandezae, R. granulosa, and Melanophryniscus cupreuscapularis. The primary objectives were to analyze the diet and pattern of coexistence relative to the microhabitats among species. The bufonids, which are primarily terrestrial, exhibited a preference for small, hard prey such as formicids or coleopterans. The smallest species preferably consumed ants, while R. schneideri preferred beetles. Significant differences were detected for the diets of these five species. In addition, significant overlap in the trophic niche was noted for all species except between R. granulosa and R. schneideri. Studying the diet behaviors and trophic parameters of sympatric species provides important data for understanding the community and for the development of conservation guidelines.
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01 Dec 2010
TL;DR: This work analyzed partitioning of microhábitats by five species of frogs in the families Bufonidae, Leiuperidae, and Leiuaridae in six different localities of the Colombian Caribean with tropical dry forest fragments and different land uses.
Abstract: We analyzed partitioning of microhábitats by five species of frogs in the families Bufonidae (Rhinella marina, R. granulosa), and Leiuperidae (Engystomops pustulosus, Pleurodema brachyops and Pseudopaludicola pusilla) in six different localities of the Colombian Caribean with tropical dry forest fragments and different land uses. We identified 29 types of microhábitats; permanent ponds in pastures with trees (CPPA) and flooded pastures without trees (PISA) were the most important environmental used. Engystomops pustulosus used the must microhábitats, and none are used by specialist species. Thus, differences Acta biol. Colomb., Vol. 15 N.o 3, 2010 47 60
2 citations
TL;DR: Results showed that the E. bicolor foraging activity followed a circadian cycle that is regulated by several climatic variables, and that these frogs aggregated when foraging for ants.
Abstract: We analyzed spatio-temporal patterns and behavior of the foraging activity of the myrmecophagous frog Elachistocleis bicolor . We delimit ten 1m2 plots and recorded the number of frogs, distance between individuals and foraging behavior at half-hour intervals, during nine days. Using a generalized linear mixed model, we evaluated the maximum, minimum, and average daily temperature, microhabitat temperature, relative humidity, atmospheric pressure, the number of days since the last rain and last 48 hours accumulated rainfall as explanatory variables of frogs’ activity. The variables that best explained frogs’ activity were: mean atmospheric pressure, number of days since last rain and accumulated rainfall. Frogs showed an aggregated distribution pattern when foraging (Morisita standardized index= 0.501). The average distance between frogs was 47.53±25.28 mm. Frogs displayed a combined (active-passive) foraging strategy, actively searching ant trails, digging with their heads on trails running under the mulch, and them passively preying on ants as they pass through. Results showed that the E. bicolor foraging activity followed a circadian cycle that is regulated by several climatic variables, and that these frogs aggregated when foraging for ants.
2 citations
Cites background from "Niche overlap and resource partitio..."
...…trophic plasticity, foraging modes, intraspecific trophic segregation (e.g. among sexes and age classes) and trophic resources partitioning among sympatric and syntopic species (Toft 1981, Maneyro and da Rosa 2004, Duré et al. 2009, López et al. 2007, 2015, Falico et al. 2012, Matsui 2016)....
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...While microhabitat segregation could diminish trophic niche overlap with sympatric nocturnal toads of genus Rhinella (Duré and Kher 2004, Duré et al. 2009, Matsui 2016)....
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...Along its distribution area, E. bicolor is sympatric with diurnal and nocturnal mirmecophagous anurans (e.g. Bonansea and Vaira 2007, Duré et al. 2009, Da Rosa et al. 2002, Bortolini et al. 2013)....
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...In this study area, E. bicolor is syntopic with Rhinella fernanadezae (Gallardo, 1957), which also specializes in ant predation in open terrestrial habitats (Duré et al. 2009); but we did not observe E. bicolor overlapping foraging microhabitats with R. fernanadezae in the RECU....
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...Elachistocleis bicolor preference for small, hard prey like ants or mites (Solé et al. 2002, Berazategui et al. 2007, López et al. 2007, Cossovich et al. 2011), coincides with the feeding preference of other specialist anurans (Toft 1981, Lajmanovich 1995, Duré et al. 2009)....
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01 Jan 2012
TL;DR: The observations show that R. jimi stops feeding during the final stages of metamorphosis, and recommences once the tail has been completely absorbed, and the existence of small sized prey is therefore crucial for maintenance of newly recruits.
Abstract: Most anuran species present a biphasic life cycle, with an aquatic larval stage that metamorphoses into terrestrial adults. Dietary aspects of newly metamorphosed froglets differ from those of both larvae and adults. Considering the important role that recruitment of newly metamorphosed froglets has on population dynamics, it is essential to understand the trophic relations during the final stages of metamorphosis. In the present study, we investigated the diet of recently metamorphosed individuals of Rhinella jimi in a rainforest area located in northeastern Brazil. Sampling took place at the end of dry season. Our main objective was to answer the following questions: i) When do froglets of R. jimi begin feeding? ii) What is their diet composition? iii) Is prey size related with predator size? We collected 34 froglets, of which 38.2% had tail remains, all of those presenting empty stomachs. Forty-six prey items belonging to 11 categories were found in the fourteen individuals without tails. Our observations show that R. jimi stops feeding during the final stages of metamorphosis, and recommences once the tail has been completely absorbed. The number of prey items per stomach ranged from one to six, and was not statistically correlated with SVL, but the latter was positively correlated with maximum prey length and volume. Diptera was the most consumed prey (26.1%) and also the most frequent (53.8%). Formicidae represented the highest volumetric proportion (34.4%), followed by Diptera (30.9%). Considering the IRI, Diptera and Formicidae were the two most important prey categories, whereas prey diversity was 0.86 and the standardized niche amplitude was 0.53. According to our data and other studies, the exact stage at which feeding recommences during final stages of metamorphosis seems to be species-specific. When terrestrial prey begins to be ingested, recently metamorphosed froglets add novel items to their trophic spectrum as they grow and mouth gape enlarges. The existence of small sized prey (< 1.5 mm) is therefore crucial for maintenance of newly recruits.
2 citations
TL;DR: En esta contribucion se dan a conocer nuevas poblaciones de R. azarai para la provincia de Corrientes (Argentina), y se brinda informacion sobre the composicion of the dieta de una of ellas.
Abstract: En esta contribucion se dan a conocer nuevas poblaciones de R. azarai para la provincia de Corrientes (Argentina), y se brinda informacion sobre la composicion de la dieta de una de ellas.
2 citations
Cites background from "Niche overlap and resource partitio..."
...Esta tendencia al consumo de hormigas coincide con lo observado en otras especies de Rhinella del grupo granulosa del nordeste argentino, tales como R. bergi, R. major y R. fernandezae (Duré et al., 2009)....
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References
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Book•
01 Jan 1948
TL;DR: The Mathematical Theory of Communication (MTOC) as discussed by the authors was originally published as a paper on communication theory more than fifty years ago and has since gone through four hardcover and sixteen paperback printings.
Abstract: Scientific knowledge grows at a phenomenal pace--but few books have had as lasting an impact or played as important a role in our modern world as The Mathematical Theory of Communication, published originally as a paper on communication theory more than fifty years ago. Republished in book form shortly thereafter, it has since gone through four hardcover and sixteen paperback printings. It is a revolutionary work, astounding in its foresight and contemporaneity. The University of Illinois Press is pleased and honored to issue this commemorative reprinting of a classic.
10,215 citations
TL;DR: In this article, a new multivariate analysis technique, called canonical correspondence analysis (CCA), was developed to relate community composition to known variation in the environment, where ordination axes are chosen in the light of known environmental variables by imposing the extra restriction that the axes be linear combinations of environmental variables.
Abstract: A new multivariate analysis technique, developed to relate community composition to known variation in the environment, is described. The technique is an extension of correspondence analysis (reciprocal averaging), a popular ordination technique that extracts continuous axes of variation from species occurrence or abundance data. Such ordination axes are typically interpreted with the help of external knowledge and data on environmental variables; this two—step approach (ordination followed by environmental gradient identification) is termed indirect gradient analysis. In the new technique, called canonical correspondence analysis, ordination axes are chosen in the light of known environmental variables by imposing the extra restriction that the axes be linear combinations of environmental variables. In this way community variation can be directly related to environmental variation. The environmental variables may be quantitative or nominal. As many axes can be extracted as there are environmental variables. The method of detrending can be incorporated in the technique to remove arch effects. (Detrended) canonical correspondence analysis is an efficient ordination technique when species have bell—shaped response curves or surfaces with respect to environmental gradients, and is therefore more appropriate for analyzing data on community composition and environmental variables than canonical correlation analysis. The new technique leads to an ordination diagram in which points represent species and sites, and vectors represent environmental variables. Such a diagram shows the patterns of variation in community composition that can be explained best by the environmental variables and also visualizes approximately the "centers" of the species distributions along each of the environmental variables. Such diagrams effectively summarized relationships between community and environment for data sets on hunting spiders, dyke vegetation, and algae along a pollution gradient.
5,689 citations
"Niche overlap and resource partitio..." refers methods in this paper
...Relationships between microhabitat and diet and foraging strategy for these five species were tested through a canonical correspondence analysis (CCA) (Ter Braak 1986, 1987)....
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31 Dec 1968
TL;DR: Professor Levins, one of the leading explorers in the field of integrated population biology, considers the mutual interpenetration and joint evolution of organism and environment, occurring on several levels at once.
Abstract: Professor Levins, one of the leading explorers in the field of integrated population biology, considers the mutual interpenetration and joint evolution of organism and environment, occurring on several levels at once. Physiological and behavioral adaptations to short-term fluctuations of the environment condition the responses of populations to long-term changes and geographic gradients. These in turn affect the way species divide the environments among themselves in communities, and, therefore, the numbers of species which can coexist. Environment is treated here abstractly as pattern: patchiness, variability, range, etc. Populations are studied in their patterns: local heterogeneity, geographic variability, faunistic diversity, etc.
3,628 citations
"Niche overlap and resource partitio..." refers methods in this paper
...For numerical data we calculated niche breadth using the Levins Index (Levins 1968): Nb Pij= ∑ −( )2 1 , where Pij represents the probability of finding the item i in the sample j....
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...For numerical data we calculated niche breadth using the Levins Index (Levins 1968):...
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TL;DR: To conclude with a list of questions appropriate for studies of resource partitioning, questions this article has related to the theory in a preliminary way.
Abstract: To understand resource partitioning, essentially a community phenomenon, we require a holistic theory that draws upon models at the individual and population level. Yet some investigators are still content mainly to document differences between species, a procedure of only limited interest. Therefore, it may be useful to conclude with a list of questions appropriate for studies of resource partitioning, questions this article has related to the theory in a preliminary way. 1) What is the mechanism of competition? What is the relative importance of predation? Are differences likely to be caused by pressures toward reproductive isolation? 2) Are niches (utilizations) regularly spaced along a single dimension? 3) How many dimensions are important, and is there a tendency for more dimensions to be added as species number increases? 4) Is dimensional separation complementary? 5) Which dimensions are utilized, how do they rank in importance, and why? How do particular dimensions change in rank as species nuimber increases? 6) What is the relation of dimensional separation to difference in phenotypic indicators? To what extent does the functional relation of phenotype to resource characteristics constrain partitioning? 7) What is the distance between mean position of niches, what is the niche standard deviation, and what is the ratio of the two? What is the niche shape?
3,626 citations
"Niche overlap and resource partitio..." refers background in this paper
...The degree of niche differentiation among species in the same trophic level depends on many factors, been prey availability one of the most relevant (Pianka 1969, Schoener 1974, 1989)....
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TL;DR: The topic here is the structure of lizard communities in this somewhat loose sense of the word (perhaps assemblage would be a more accurate description), with emphasis on the niche relationships among such sympatric sets of lizard species, especially as they affect the numbers of species that coexist within lizard communities.
Abstract: Strictly speaking, a community is composed of all the organisms that live together in a particular habitat. Community structure concerns all the various ways in which the members of such a community relate to and interact with one another, as well as community-level properties that emerge from these interactions, such as trophic structure, energy flow, species diversity, relative abundance, and community stabil ity. In practice, ecologists are usually unable to study entire communities, but instead interest is often focused on some convenient and tractable subset (usually taxonomic) of a particular community or series of communities. Thus one reads about plant communities, fish communities, bird communities, and so on. My topic here is the structure of lizard communities in this somewhat loose sense of the word (perhaps assemblage would be a more accurate description); my emphasis is on the niche relationships among such sympatric sets of lizard species, especially as they affect the numbers of species that coexist within lizard communities (species den sity). So defined, the simplest (and perhaps least interesting) lizard communities would be those that contain but a single species, as, for instance, northern populations of Eumeces msciatus. At the other extreme, probably the most complex lizard commu nities are those of the Australian sandridge deserts where as many as 40 different species occur in sympatry (20). Usually species densities of sympatric lizards vary from about 4 or 5 species to perhaps as many as 20. Lizard communities in arid regions are generally richer in species than those in wetter areas; therefore, because almost all ecological studies of entire saurofaunas have been in deserts (l8, 20, 25), this paper emphasizes the structure of desert lizard communities. As such, I review mostly my own work. Other studies on lizard communities in nondesert habitats are, however, cited where appropriate. Historical factors such as degree of isolation and available biotic stocks (particu larly the species pools of potential competitors and predators) have profoundly shaped lizard communities. Thus one reason the Australian deserts support such very rich lizard communities may be that competition with, and perhaps predation pressures from, snakes, birds, and mammals are reduced on that continent (20).
2,406 citations
"Niche overlap and resource partitio..." refers methods in this paper
...We calculated dietary overlaps in two ways by considering the food proportions and the volume of each prey with the formula (Pianka 1973): O P P P P jk ij ik i n ij ik i n i n = = == ∑ ∑∑ 1 2 2 11 , where Pij and Pik are the proportions of utilization of the ith food resource by the jth and kth…...
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...We calculated dietary overlaps in two ways by considering the food proportions and the volume of each prey with the formula (Pianka 1973):...
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