scholarly journals Wetland selection, niche breadth and overlap in 10 duck species wintering in northern Campania (Italy)

2018 ◽  
Vol 87 (2) ◽  
pp. 3-8
Author(s):  
Stefano Giustino ◽  
Marcello Bruschini ◽  
Elio Esse ◽  
Silvana Grimaldi ◽  
Danila Mastronardi ◽  
...  
Keyword(s):  
Niche Breadth ◽  
Selection Index ◽  
Niche Overlap ◽  
Campania Region ◽  
Duck Species ◽  
Wintering Area ◽  
Morisita Index ◽  
Species Preferences

Analysis of the selection index, the niche breadth and the niche overlap of 10 species of wintering ducks in 11 wetland areas of the Campania region between January 2003 and 2015 revealed that the distribution of the species in the examined sites was not casual. In fact, each species actively chose their wintering area. Using selection index, we were able to measure the species’ preferences and non-preferences for the 11 examined sites. By calculating Shannon-Wiener entropy and its normalized value (Evenness), we determined niche breadth; the Morisita index allowed us to check niche overlap.

scholarly journals Ecology of colonizing populations of the figfly Zaprionus indianus (Diptera, Drosophilidae) in Porto Alegre, Southern Brazil

2005 ◽  
Vol 95 (3) ◽  
pp. 233-240 ◽  
Author(s):  
Norma Machado da Silva ◽  
Carina da Conceição Fantinel ◽  
Vera Lucia da Silva Valente ◽  
Vitor Hugo Valiati
Keyword(s):  
Niche Breadth ◽  
Niche Overlap ◽  
Trophic Niche ◽  
Survival Strategies ◽  
Porto Alegre ◽  
Zaprionus Indianus ◽  
Feeding Sites ◽  
Substrate Choice ◽  
Oviposition Substrate ◽  
Feeding Substrate

Ecological parameters such as trophic niche overlap and niche breadth were computed from the frequency of all drosophilid species collected in 2001 and 2002, in the urban area of Porto Alegre city, Brazil. Independently of place, drosophilids community composition and components breeding or feeding sites, the highest frequencies of Zaprionus indianus (Gupta, 1970) were obtained during seasons with higher average temperatures, especially during summer. From a total of the 19,146 individuals of Z. indianus sampled, 80% were found in this season. The data of trophic niche breadth suggest a higher opportunism of adult flies in feeding substrate use, but the females are still selective in oviposition substrate choice. For the values of niche overlap, only for some species, did we find any correlation between these and species richness and/or number of resources, and the most of the correlation values considering breeding and feeding sites were positive. The colonization of Z. indianus in Porto Alegre could be leading to adjustments in the survival strategies of the resident species, but it is possible that many species have conditions for coexisting with the invader.

scholarly journals Trophic interactions among sympatric zooplanktivorous fish species in volume change conditions in a large, shallow, tropical lake

2011 ◽  
Vol 9 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Rodrigo Moncayo-Estrada ◽  
Owen T Lind ◽  
Carlos Escalera-Gallardo
Keyword(s):  
Niche Breadth ◽  
Temporal Distribution ◽  
Niche Overlap ◽  
Species Interaction ◽  
Trophic Relationships ◽  
Water Volume ◽  
Species Flock ◽  
Small Range ◽  
Mean Values ◽  
Significant Difference

Significant reductions in the water volume of shallow lakes impose a restriction on species segregation promoting more interactions in the trophic relationships. The diets of three closely related zooplanktivorous silversides belonging to the Atherinopsidae species flock of lake Chapala , Mexico, were analyzed at two sites (Chirostoma jordani, C. labarcae, and C. consocium). Diets were described in critical shallow (August 2000) and volume recovery conditions (August 2005). Diets included mainly cladocerans (Bosmina, Ceriodaphnia, and Daphnia) and copepods (Cyclops). A significant difference in diets was detected when comparing years (MRPP analysis, A = 0.22, p < 0.0001) and sites at different years (MRPP analysis, A = 0.17, p = 0.004). According to niche breadth mean values, species were classified as specialized and intermediate feeders. In shallow conditions, the small range of niche breadth (1.72 to 3.64) and high diet overlap values (D = 0.64, L = 8.62) indicated a high potential for interspecific exploitative interaction. When the lake volume recovered, an increase in the niche breadth range (1.04 to 4.96) and low niche overlap values (D = 0.53, L = 2.32) indicated a reduction of the species interaction. The Mann-Whitney U-test supported this pattern by showing a significant difference between years for niche overlap (p = 0.006). The increased interaction during the low volume suggests alternative segregation in life-history variations and other niche dimensions such as spatial or temporal distribution.

Assessing the diet and trophic niche breadth of an omnivorous fish (Glanidium ribeiroi) in subtropical lotic environments: intraspecific and ontogenic responses to spatial variations

2019 ◽  
Vol 70 (8) ◽  
pp. 1116 ◽  
Author(s):  
B. C. K. Kliemann ◽  
M. C. Baldasso ◽  
S. F. R. Pini ◽  
M. C. Makrakis ◽  
S. Makrakis ◽  
...  
Keyword(s):  
Forest Cover ◽  
Agricultural Land ◽  
Niche Breadth ◽  
Intraspecific Variability ◽  
Niche Overlap ◽  
Trophic Niche ◽  
Main Channel ◽  
Size Classes ◽  
Intraspecific Variations ◽  
Environmental Variations

The diet of Glanidium ribeiroi was investigated in lotic stretches downstream from a cascade of reservoirs to determine how it responds to intraspecific and environmental variations. Monthly sampling was performed from 2013 to 2016 at sites including the main channel of the Iguaçu River and tributaries in preserved basins and agricultural land. The diet of individuals in the preserved tributaries was primarily associated with allochthonous resources, whereas in the non-preserved tributaries and main channel the diets were primarily associated with autochthonous resources. Trophic niche breadth and intraspecific variability differed significantly among sampling areas and size classes. Trophic niche overlap among size classes and sampling areas was low. Positive and negative relationships between the trophic niche breadth and the standard length of individuals were also found in different sampling areas. Intraspecific and ontogenic variations were strongly and consistently associated with forest cover. Individuals responded differently to local environmental variations due to differences in landscape gradients and life cycle changes. Therefore, the effects of spatial heterogeneity on diet composition and intraspecific variations therein appear to be crucial to the success of the populations evaluated. These results may help with the implementation of conservation measures for this and other endemic species.

scholarly journals Resource use by two electric fishes (Gymnotiformes) of the National Forest Saracá-Taquera, Oriximiná, Pará

2017 ◽  
Vol 15 (2) ◽  
Author(s):  
Bruno E. Soares ◽  
Daniela C. O. Rosa ◽  
Nathália C. S. Silva ◽  
Miriam P. Albrecht ◽  
Érica P. Caramaschi
Keyword(s):  
Resource Use ◽  
Niche Breadth ◽  
Feeding Strategy ◽  
Stomach Contents ◽  
Niche Overlap ◽  
Feeding Strategies ◽  
National Forest ◽  
Microhabitat Use ◽  
Use Patterns ◽  
Head Morphology

ABSTRACT Fishes of the order Gymnotiformes have high diversity of oral and head morphology, which suggests trophic specializations within each clade. The aim of this study was to describe resource use patterns by two fish species (Gymnorhamphichthys rondoni and Gymnotus coropinae) in the National Forest Saracá-Taquera, Oriximiná - Pará, analyzing microhabitat use, diet composition, feeding strategies, niche breadth and niche overlap. Stomach contents of 101 individuals (41 G. rondoni and 60 G. coropinae), sampled in 23 headwater streams were analyzed and volume of food items was quantified to characterize their feeding ecology. Gymnorhamphichthys rondoni was captured mainly on sandy bottoms, whereas G. coropinae in crevices. Both species had a zoobenthivorous diet and consumed predominantly Sediment/Detritus and Diptera larvae, but also included allochthonous prey in their diet. These species had high niche overlap, with small variations related to the higher consumption of Ceratopogonidae larvae by G. rondoni and of Chironomidae larvae by G. coropinae. Both species had a generalist feeding strategy, but G. coropinae had a broader niche breadth. Our results demonstrate that G. rondoni and G. coropinae occupy different microhabitats but rely on similar food resources.

Niche breadth and niche overlap in three epixylic hepatics in a boreal old-growth forest, southern Finland

2005 ◽  
Vol 27 (2) ◽  
pp. 119-127 ◽  
Author(s):  
Sanna Laaka-Lindberg ◽  
Maria Pohjamo ◽  
Helena Korpelainen
Keyword(s):  
Niche Breadth ◽  
Niche Overlap ◽  
Old Growth ◽  
Old Growth Forest

scholarly journals Feeding habits and microhabitat utilization by two syntopic Brazilian Amazonian frogs (Hyla minuta and Pseudopaludicula sp. (gr. falcipes)

1998 ◽  
Vol 58 (4) ◽  
pp. 559-562 ◽  
Author(s):  
M. VAN SLUYS ◽  
C. F. D. ROCHA
Keyword(s):  
Diet Composition ◽  
Niche Breadth ◽  
Feeding Habits ◽  
Niche Overlap ◽  
Microhabitat Use ◽  
Feeding Niche ◽  
Frog Species

We studied the feeding habits and microhabitat use of the Amazonian frogs Hyla minuta and Pseudopaludicula sp. at Serra Norte, Carajás, Brazil. Although living syntopically, the two species differed markedly in both prey types and sizes. Standardized feeding niche breadth of H. minuta (Bst = 0.572) was larger than that of Pseudopaludicula sp. (Bst = 0.149) and their feeding niche overlap was considerably low (10.5%). The two frog species also differed in microhabitat use. When active, Pseudopaludicula sp. were found partially submerged at the lake border whereas H. minuta were found predominantly on Nymphaea sp. leaves. Although we have not evaluated taxonomic effects on diet composition, differences in diet may be partially explained by differences in microhabitat use and frogs' size.

scholarly journals Research on The Evolution of High-tech Industry Competitiveness in Beijing-Tianjin-Hebei

2021 ◽  
Vol 248 ◽  
pp. 02023
Author(s):  
LI Yanxia ◽  
Jie Zhang
Keyword(s):  
Ecological Niche ◽  
Niche Breadth ◽  
Niche Overlap ◽  
Evaluation Index System ◽  
Niche Width ◽  
High Tech ◽  
Growth Trend ◽  
High Tech Industry ◽  
Increasing Trend ◽  
Industry Competitiveness

From the perspective of ecological niche, this paper constructs the evaluation index system of the competitiveness of beijing-tianjin-hebei high-tech industry, and analyzes the competitiveness of beijing-tianjin-hebei high-tech industry from the perspectives of niche value, niche width and niche overlap. The results show that :(1) from the perspective of ecological niche, the niche value of the competitiveness of high-tech industries in Beijing, tianjin and hebei does not show an increasing trend with time, and the overall value of the niche is ranked from the largest to the smallest: Beijing, tianjin and hebei.(2) from the niche breadth, beijing-tianjin-hebei high-tech industry competitiveness niche breadth range as follows: 0.26-0.83, Beijing niche width of the widest, hebei niche breadth the narrowest, Beijing and tianjin hi-tech industry competitiveness niche breadth value reduced trend on the whole, hebei niche breadth on overall growth trend.

scholarly journals Ekologi Media Radio Siaran di Yogyakarta: Kajian Teori Niche terhadap Program Acara Radio Siaran di Propinsi Daerah Istimewa Yogyakarta

2013 ◽  
Vol 4 (2) ◽  
Author(s):  
F. Anita Herawati ◽  
Setio Budi HH
Keyword(s):  
Niche Breadth ◽  
Niche Overlap ◽  
Niche Theory ◽  
Unit Of Analysis ◽  
Radio Program

Abstract: This article describes the radio competition in Yogyakarta at 2005. The radio competition was measured by using niche theory and as an unit of analysis is radio program. Niche theory was applied by measuring niche breadth and niche overlap. Niche breadth shows the degree of radio competition which focuses on the source of media life. Another measurement is niche overlap. This concept is used to measure what radio becomes competitor to certain radio. This research shows that the radio industries in Yogyakarta tend to be specialist radio and the radio competition is very strong.

scholarly journals Diet and trophic niche overlap of Boana bischoffi and Boana marginata (Anura: Hylidae) in southern Brazil

2018 ◽  
Vol 19 (1) ◽  
Author(s):  
Camila F. Moser ◽  
Mateus de Oliveira ◽  
Fernanda R. de Avila ◽  
Diogo Dutra-Araújo ◽  
Renata K. Farina ◽  
...  
Keyword(s):  
Natural History ◽  
Atlantic Forest ◽  
Diet Composition ◽  
Niche Breadth ◽  
Niche Overlap ◽  
Food Composition ◽  
Trophic Niche ◽  
Southern Brazil ◽  
Important Prey ◽  
History Of

Abstract: The species Boana bischoffi and Boana marginata are endemic to the Atlantic Forest, where they often occur in sympatry. There is a large gap in the knowledge of natural history of both species. In this study, we aimed to describe and compare the diet composition of B. bischoffi and B. marginata in the southern domain of the Brazilian Atlantic Forest. We analyzed the gastrointestinal contents of 43 individuals of B. bischoffi and 30 individuals of B. marginata. Both showed a high trophic niche overlap (0.90 Ojk). The most important prey categories for both species belonged to the orders Araneae and Coleoptera. The species niche breadth (Bsta) varied from 0.35 to 0.42, suggesting a generalist feeding behavior for both species. Our data provide unprecedented information on these species' food composition, contributing to a better knowledge of the natural history of neotropical anurans.

A Niche-Based Evaluation of Sport Participation Patterns

1996 ◽  
Vol 10 (4) ◽  
pp. 417-434 ◽  
Author(s):  
George R. Milne ◽  
Mark A. McDonald ◽  
William A. Button ◽  
Rajiv Kashyap
Keyword(s):  
Ecological Niche ◽  
Sport Participation ◽  
Niche Breadth ◽  
Niche Overlap ◽  
Advertising Agencies ◽  
Resource Overlap ◽  
Managerial Implications ◽  
Sporting Goods ◽  
Corporate Sponsors ◽  
Sports Activities

This research examines the competitive niche positions of 36 sports and fitness activities reported in an American Sports Activities 1993 tracking study. The article discusses the advantages of viewing competition from an ecological niche perspective and presents a measure of competitive resource overlap (CRO) used in marketing for measuring niche breadth and niche overlap. The empirical study presents an intuitive mapping of the sports market and calculates the niche breadth and niche overlap for each sport. Managerial implications for sporting goods manufacturers, advertising agencies, corporate sponsors, fitness consultants, and other professionals interested in participant sports markets are given.

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