Feeding ecology

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Summer feeding ecology of great pampa-finches, Embernagra platensis at Laguna de Guaminí, Buenos Aires, Argentina

Summer feeding ecology of great pampa-finches, Embernagra platensis at Laguna de Guaminí, Buenos Aires, Argentina

In order to discuss the feeding ecology of the Great Pampa-finch during the summer, we made some com- parisons concerning the proportions and the diversity of prey items ingested between the two seasons when possible. The specimens collected had consumed 17% of seeds (biomass) in the summer and 60% in the winter. Plant seed families were Chenopodiaceae, Asteraceae, Cyperaceae, and Poaceae for the winter, and they dif- fered from the summer in certain species, namely He- lianthus annuus, Setaria ssp., Zea mays, and Eleusine tristachia (Montalti et al. 2005). The summer plant species diverged considerably from the winter species (Table II), but they were all local components, both cul- tivated and ornamental crops. We assume that the un- determined vegetal fraction was obtained as part of in- digestible seed husks and grass that were picked while birds were eating fallen seeds. Wheat and corn were ob- tained from leftover crops at the end of August-Novem- ber. The harvesting activity spreads native and exotic seeds, but also grain storage offers “free” nourishment, especially for pest insects commonly preyed upon seed- eating birds. Even though seeds are important compo- nents of the winter diet, during the nesting season most of the birds feed on insects. Energy and protein require- ments increase in birds during breeding (Klasing 1998). Arthropod ingestion provides more nutrients than fruit for most passerine birds (Izhaki 1998). During the sum- mer, the amount of seeds and gastroliths decreased in comparison with the winter (Montalti et al. 2005).
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The feeding ecology of the endemic fish Girardinichthys multiradiatus (Cyprinidontiformes: Goodeidae) in Lagunas of Zempoala National Park, Mexico  [Spanish]

The feeding ecology of the endemic fish Girardinichthys multiradiatus (Cyprinidontiformes: Goodeidae) in Lagunas of Zempoala National Park, Mexico [Spanish]

Abstract: The feeding ecology of the endemic fish Girardinichthys multiradiatus (Cyprinidontiformes: Goodeidae) in Lagunas of Zempoala National Park, Mexico. Girardinichthys multiradiatus, locally known as “mexcalpique”, is a small endemic fish of the Lerma river basin. Its presence in lakes (Zempoala) suggests a long-standing connection between these lakes and the river basin. The current range of this species in the Mexico and Toluca valley appears to have been reduced, making this park a refuge for the species. Nevertheless, little is known about its biology. We studied its diet and feeding habits in Acoyotongo Lake, Lagunas de Zempoala National Park (19°01’30”-19°06’ N, 99°16’20”-99°21’ W) where seasonal collections were carried out. The gut contents of 97 specimens were identified to the most specific taxonomic category possible and analyzed with numeric and frequency of occurrence methods. The general diet of this species consists of twelve dietary components, eleven of which are of animal origin. Hymenopterans, springtails and chironomids represented the highest percentage of ingestion and preference. G. multiradiatus is as a carnivorous species with entomophagous tendencies. Rev. Biol. Trop. 54 (4): 1247-1255. Epub 2006 Dec. 15.
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A twelve month field study of the West African Thrush Turdus pelios (Passeriformes: Muscicapidae)  Part 1: food and feeding ecology

A twelve month field study of the West African Thrush Turdus pelios (Passeriformes: Muscicapidae) Part 1: food and feeding ecology

Abstract: The feeding ecology of Turdus pelios was studied from field observations and gizzard contents. Quantitative data on feeding were obtained from repeated standard “fixed route” walks and observational points at seven sites from January to December 1998 on 5065ha at the Obafemi Awolowo University campus, Ile-Ife (7º20’ N, 4º33’ E). Walks (each lasting about two hours) were started at various times of the day between 7.00 and 16.45 h. A total of 100 walks were made and binoculars were used to observe all feeding activities during 10 minutes at each site. Each feeding record included food type, method of feeding and reaction with con-specifics at feeding sites. Gizzards from mist-netted specimens were also studied. These birds fed most commonly twice a day between 06.00-9.30hr in the morning and between 17.00-18.30hr in the evening. Field observations showed that about 62% of the diet consisted of plant matter. The prey items were earthworms and terrestrial arthropods, of which orthopterans alone constituted 45% of the total. The prey size consumed by both sexes overlapped extensively: differences in prey size were significant only for spiders. Rev. Biol. Trop. 52(4): 1001-1007. Epub 2005 Jun 24.
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Feeding ecology of the siluriform Pimelodella laticeps Eigenmann, 1917 in a Pampean stream from Argentina

Feeding ecology of the siluriform Pimelodella laticeps Eigenmann, 1917 in a Pampean stream from Argentina

The relative abundance of each item was obtained and the feeding habits compared be- tween the different seasons through analysis of the gut-content-abundance values by means of a nonparametric multivariate analysis (a permuta- tion-based one-way ANOSIM; Clarke & Warwick, 2001). In this way, a similarity-percentage analy- sis (SIMPER) was used to identify the so-called discriminating items that most highly contrib- uted to accounting for the observed similarity (or dissimilarity) between samples. This method uses the Bray-Curtis measure of similarity by compar- ing, in succession, each sample in one group with every sample in another set. Finally, in order to understand the feeding strategies of P. laticeps, the fish’s diet was compared with the plankton availability recorded by Macluf et al. (1998). This plankton community was analyzed by means of the Olmstead-Tukey method (Sokal & Rolf, 1979), a nonparametric association test that allows to de- terminate dominant, frequent, rare, and common items. This information was also used to compare by multivariate analysis (ANOSIM) between the plankton available in the environment and the consumed items of this assemblage. SIMPER was also used to identify the discriminating items accounting for this similarity (or dissimilarity). Before both analyses, the rare species were dis- carded from the general matrix, and the data were then transformed to log(x + 1) to reduce the contribution of the most highly abundant species. For these comparisons, fish and plank- ton samples were obtained at the same time (as explained in reference to the study area above).
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The cranial osteology and feeding ecology of the Metriorhynchid Crocodylomorph Genera Dakosaurus and Plesiosuchus from the late Jurassic of Europe

The cranial osteology and feeding ecology of the Metriorhynchid Crocodylomorph Genera Dakosaurus and Plesiosuchus from the late Jurassic of Europe

Furthermore, the difference in ‘optimum gape’ is considerable between Plesiosuchus manselii and Dakosaurus maximus (Fig. 31, Table 3). This suggests that these two species had distinct feeding ecologies. Unfortunately, without better preserved specimens we cannot attempt to reconstruct the occlusion mechanics of Plesiosuchus manselii. Regardless, the Plesiosuchus skull was not as well-suited to resist high stresses (in particular torsion) when compared to D. maximus, because it lacks an oreinirostral snout and ‘lateral plates’ on dentigerous bones; but coupled with its larger body-size (see above and [14]) and greater ‘optimum gape’ (Table 3) Plesiosuchus could have fed upon larger bodied prey. When directly comparing the ‘optimum prey depth’ at the same mandibular length (60 cm, see Table 3), there is a significant difference between P. manselii and D. maximus (12.6 cm vs 9 cm respectively). Interestingly, extant odontocete species that are sympatric and share a similar diet limit inter-specific competition by predating upon prey items of different size (such as the cephalopod specialists the sperm whale and the pygmy sperm whale, with the former predating upon larger-bodied cephalopod species than the latter) [112]. At the very least, it is clear that D. maximus and P. manselii had distinct morphologies and different sets of feeding-related characters, which may help explain why these two large-bodied crocodylomorphs were able to coexist in the same ecosystem.
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Feeding ecology of the Burrowing Owl Athene cunicularia punensis (Strigiformes: Strigidae) in the Jambelí archipelago, El Oro province, southwestern Ecuador

Feeding ecology of the Burrowing Owl Athene cunicularia punensis (Strigiformes: Strigidae) in the Jambelí archipelago, El Oro province, southwestern Ecuador

Estudiamos la dieta del búho terrestre Athene cunicularia punensis en cuatro territorios dentro del archipiélago de Jambelí, provincia de El Oro, suroeste de Ecuador, entre noviembre [r]

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Miles et al 2019 Molecular Ecology pdf

Miles et al 2019 Molecular Ecology pdf

A related issue is that North American and European cities in temperate areas are overrepresented in the studies we reviewed (Figure 1). Thus, our understanding of the interaction between ur‐ banization and environmental conditions is limited by both the small geographic range and the limited climatic variation represented in the existing literature. Future studies are needed that incorporate cities in more diverse ecological, climatic, anthropogenic, temporal and spatial characteristics (Alberti, 2015; Grimm et al., 2008). For example, the Western United States has recently become highly urbanized (US Census, 2014) and has a diversity of ecoregions in‐ cluding deserts, grasslands, Mediterranean chaparral, montane and coastal forests (Western Ecology Division EPA, 2018). Studies in these unique ecoregions of rapid growth would provide further insight into the factors that contribute to variation in patterns of genetic drift and gene flow. For example, Western black widow spi‐ ders (L. hesperus) sampled in urban and nonurban populations across the Western United States experience urban‐facilitated gene flow, but certain cities act as “hubs” in driving gene flow (Miles, Dyer, & Verrelli, 2018; Miles, Johnson, et al., 2018). The variation in both the ecoregions and the level of urbanization of the cities sampled likely play a large role in what drives variance in gene flow among popu‐ lations (Miles, Dyer, et al., 2018). In addition, new initiatives like the Global Urban Evolution Project (GLUE; www.globa lurba nevol ution. comcom), which has representation from cities across six continents, may help resolve global patterns in urban evolution (Rivkin et al., 2018).
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La huella ambiental de McLuhan | Media Ecology Association

La huella ambiental de McLuhan | Media Ecology Association

La décima obra sobre la que se erigen los cimientos de los estudios de Ecología de los medios y sobre la que pivotan las actuaciones de la Media Ecology Asso- ciation es la de Marshall McLuhan; quien en la década de los sesenta comenzó a estructurar sus inquietudes sobre la relación entre las nuevas extensiones tecnológicas, características de su Era Electrónica, y el ser humano en el Centre For Culture and Technology, ubicado a partir de 1968 en la afamada Coach Hou- se de la Universidad de Toronto y con- vertido, tras su muerte, en el McLuhan Program in Culture and Technology: un mandato destinado a estimular el enten- dimiento de los efectos de la tecnología en la cultura y la sociedad, tanto desde una perspectiva teórica, como práctica.
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Ecocriticism, Cultural Ecology, and Literary Studies

Ecocriticism, Cultural Ecology, and Literary Studies

movements from the 18 th to the 21 st century. Literature in the perspective of cultural ecology is thus a distinct form of cultural-ecological knowledge, which integrates but also transcends empirical, factual, and quantifiable forms of knowledge, including scientific versions of ecology.

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THE NEW MEDIA ECOLOGY OF STUDENTS

THE NEW MEDIA ECOLOGY OF STUDENTS

New gadgets allow people to enjoy media, gather information, and carry on communication anywhere. and any time.[r]

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The method comparative method in plant ecology

The method comparative method in plant ecology

ferencias sobre el valor adaptativo de los caracteres. En general, cuando empleamos el método compara- tivo lo hacemos en combinación con otras técnicas que nos permitan [r]

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Realimentación en diarrea infantil  Feeding in pediatric diarrea

Realimentación en diarrea infantil Feeding in pediatric diarrea

In children with diarrhea, the premise continues being valid: first to hydrate for soon feeding. Also, it’s necessary to need before reinitiating its feeding, three important factors that interrelate to each other: the time of evolution and characteristics of the diarrhea and the age and nutritional status of the children.

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Ecology
of protest. How law observes disobedience

Ecology of protest. How law observes disobedience

If systems theory is, therefore, an ecological theory, it can easily be maintained that the function of protest too is an ecological function, regardless of whether or not the protest in question is an environmental protest. Protest can indeed be described as an invitation to observe the periphery, that which is relegated to the environment – the other part concealed by latency. Protest reveals that there is always an environment, whether this be nature or the involved: those who do not decide, but who are impacted by the decisions of the decision-maker, those who can become decision- makers. Protest reveals that there is another part, that society’s self-description – which is constructed in its centre by the political, economical or juridical system – is only one description, without any character of necessity. The ecological function of protest is to show the contingency of reality, to carry the centre to the periphery and the periphery to the centre: revealing that alternatives exist, indicating the unmarked space, the other part left in the shadows. Protest is ecology of the otherness of the viewpoint of the other: it is the ecology of multiplicity.
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Ecology and evolution of pollination by deception

Ecology and evolution of pollination by deception

Universidad Nacional Autónoma de México A.P. En este artícu lo revisamos los aspectos eco lógi cos y evo luti vos del síndrome de polinización por engaño. Este tipo [r]

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Locusts and grasshoppers: behavior, ecology, and biogeography

Locusts and grasshoppers: behavior, ecology, and biogeography

Sergeev, “Comparative biogeog- raphy of grasshoppers (Orthoptera: Acrididae) in North America and Siberia: applications to the conservation of biodiversity,” Journal of Insect Conservati[r]

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Reseña de los libros: "Corridor ecology” y “Applying Nature's design"

Reseña de los libros: "Corridor ecology” y “Applying Nature's design"

Las bases científicas, los criterios generales de diseño y el modelo básico están compartidos por ambos libros, pero, mientras el libro de Hilty, Ledecker y Merelender desarrolla sus t[r]

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Distributional ecology of Andes hantavirus: A macroecological approach

Distributional ecology of Andes hantavirus: A macroecological approach

By including all components of the transmission cycle in this study  hosts, virus-exposed hosts, and terminal host infections (i.e., in humans), we explored different components of the distributional ecology of hantavi- rus; specifically, we quantified the potential distribution of six recognized native rodent reservoirs of the virus in southern South America. This is a macroecological study since it assessed biodiversity patterns at coarse spatial scale, which provides new information regard- ing suitable conditions for hantavirus transmission risk and rodent species likely involved in local trans- mission. In general, we argue that host distributions influence pathogen distributions, thereby molding the occurrence of the disease [18], which may be explained by the subset of the rodent niche occupied by hantavi- rus (Fig. 4b). This assessment may be useful for native Fig. 2 Temperature and precipitation tolerances derived from niche
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Carnivorous plants biology: ecology and evolution

Carnivorous plants biology: ecology and evolution

Es notable que las especies pertenecientes a géneros primitivos como Heliamphora utilizan únicamente el ag u a de lluvia para el funcionamiento de sus tram- pas, e[r]

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Ecology, anatomy and redescription of Laternea pussilla

Ecology, anatomy and redescription of Laternea pussilla

Ecology: The presence o f 2, 3, to 4 arms in the receptac1e was confirme d in both natural and semi-natural situations. The ratio of individuals with 2 arms to those with 3 was 1 : 5. The activity of predators and c1imatic changes, particularly variations in relative humidity, may account for the low number of fruiting bodies usually found in nature. On the other hand, prote ction of Log # 1 with c10th and insecticide , besides the constant humid environment; accounted for the large number of fruiting bodies obtained in a semi-natural situation ( I 6 fruiting bodies in 5 months). Lag #2, lackin g moisture , in a windy environment an d unprotecte d from predators failed to produce fruiting bodies. It was found that predators are attracted b y the odor of the gleba and rupture the peridium before the eggs open
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Ecology in the Magisterium of the Church

Ecology in the Magisterium of the Church

Al mismo tiempo, el documento hace un llamado de atención respecto del progreso, ya que si bien es “altamente beneficioso para el hombre también encierra, sin embargo, gran tentación, [r]

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