Interannual variation in larval survival of snapper (Chrysophrys auratus, Sparidae) is linked to diet breadth and prey availability

2012 ◽  
Vol 69 (8) ◽  
pp. 1340-1351 ◽  
Author(s):  
Hannah M. Murphy ◽  
Gregory P. Jenkins ◽  
Paul A. Hamer ◽  
Stephen E. Swearer
Keyword(s):  
Niche Breadth ◽  
Prey Availability ◽  
Larval Survival ◽  
Trophic Niche ◽  
Foraging Strategies ◽  
Feeding Strategies ◽  
Larval Abundance ◽  
Larval Diet ◽  
Larval Size ◽  
Prey Quality

Larval snapper ( Chrysophrys auratus , Sparidae) sampled over 7 years had different diets and feeding strategies between years with lower versus higher larval and 0+ abundances. We analysed stomach contents of snapper larvae from each year to determine diet composition, prey selectivity, prey quality, and trophic niche breadth and compared larval diet with prey availability. Snapper larvae from higher abundance years were specialized foragers selecting for calanoid nauplii at 2–4 mm standard length (SL) and calanoid copepodites and cladocerans at >4 mm SL. These larvae were characterized by either a constant or dome-shaped trophic niche breadth and an increase in prey quality (size of consumed prey) with increasing larval size. Snapper larvae from lower abundance years were generalist foragers characterized by an increase in trophic niche breadth, but not prey quality, with increasing larval size. Changes in foraging strategies were concordant with changes in the prey environment, with low zooplankton densities corresponding with generalist diet (lower larval abundance) years and high zooplankton densities with specialist diet (higher larval abundance) years. These findings suggest that snapper larval survival and juvenile recruitment strength is linked to changes in larval diet that relate to prey abundance and composition.

scholarly journals Adaptive foraging behaviour increases vulnerability to climate change

2021 ◽  
Author(s):  
Benoit Gauzens ◽  
Benjamin Rosenbaum ◽  
Gregor Kalinkat ◽  
Thomas Boy ◽  
Malte Jochum ◽  
...  
Keyword(s):  
Climate Change ◽  
Foraging Behavior ◽  
Dynamic Models ◽  
Species Coexistence ◽  
Prey Availability ◽  
Stomach Contents ◽  
Optimal Foraging Theory ◽  
Trophic Niche ◽  
Feeding Strategies ◽  
Adaptive Foraging

Abstract Adaptative foraging behavior should promote species coexistence and biodiversity under climate change as predators are expected to maximize their energy intake, according to principles of optimal foraging theory. We test these assumptions using a dataset comprising 22,185 stomach contents of fish species across functional groups, feeding strategies, and prey availability in the environment over 12 years. Our results show that foraging shifts from trait-dependent prey selectivity to density dependence in warmer and more productive environments. This behavioral change leads to lower consumption efficiency as species shift away from their optimal trophic niche, undermining species persistence and biodiversity. By integrating this adaptive foraging behavior into dynamic models, our study reveals higher risk profiles for ecosystems under global warming.

scholarly journals Foraging Activity and Trophic Spectrum of Red AntPogonomyrmex barbatusSmith, 1858, in Productivity-Contrasted Microenvironments

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Rafael Guzmán-Mendoza ◽  
Gabriela Castaño-Meneses ◽  
José Alejandro Zavala-Hurtado
Keyword(s):  
Niche Breadth ◽  
Arid Zone ◽  
Trophic Niche ◽  
Dry Season ◽  
Foraging Strategies ◽  
Arid Zones ◽  
Pogonomyrmex Barbatus ◽  
High Productivity ◽  
Dry Seasons ◽  
A Site

Foraging strategies can be influenced by many factors such as abundance, availability, and toxicity of the resources. In arid zones, the distribution and productivity of plants also act as additional factors that affect foraging strategies. Twenty colonies ofPogonomyrmex barbatusants were studied in an arid zone of central Mexico to evaluate the trophic niche breadth in two sites with contrasting productivities in terms of their diversity and amount of resources during two seasons. The results suggest that when the resources are abundant as in the rainy season, the trophic niche breadth is reduced in sites with high productivity and, in the same sites, the trophic niche breadth increases when the resources are limited as in the dry season. In contrast, the trophic niche breadth is similar in both conditions of resource availability (i.e., rainy and dry seasons) at sites with low productivity. During the dry season, populations ofP. barbatusshowed a similar foraging behavior in sites with high and low productivity. Thus, the particular characteristics of a site can significantly affect the foraging strategies of the ants in those environments.

scholarly journals Feeding habits and dietary overlap during the larval development of two sandperches (Pisces: Pinguipedidae)

2017 ◽  
Vol 81 (2) ◽  
pp. 195 ◽  
Author(s):  
Javier A. Vera-Duarte ◽  
Mauricio F. Landaeta
Keyword(s):  
Niche Breadth ◽  
Feeding Habits ◽  
Mouth Opening ◽  
Trophic Niche ◽  
Dietary Overlap ◽  
Austral Spring ◽  
Larval Size ◽  
Larval Stages ◽  
Nearshore Environments ◽  
Larval Species

Two species of sandperch (Pinguipedidae: Perciformes), Prolatilus jugularis and Pinguipes chilensis, inhabit the coastal waters of the South Pacific. Both species have pelagic larvae with similar morphology, but their diet preferences are unknown. Diet composition, feeding success, trophic niche breadth and dietary overlap were described during larval stages for both species. In the austral spring, larval P. jugularis (3.83-10.80 mm standard length [SL]) and P. chilensis (3.49-7.71 mm SL) during their first month of life had a high feeding incidence ( > 70%) and fed mostly on copepod nauplii ( > 80% IRI), Rhincalanus nasutus metanauplii and Paracalanus indicus copepodites. The number of prey ingested was low (mean: 4-5 prey per gut) and independent of larval size; total prey volume and maximum prey width increased as larvae grew. Mouth opening and ingested prey were greater in larval P. jugularis than in P. chilensis, leading to significant differences in prey composition among larval species, in terms of prey number and volume. Pearre’s trophic niche breadth was narrow for both species (0.159±0.07 for P. jugularis; 0.156±0.03 for P. chilensis) and independent of larval size. Dietary overlap was high inter- and intra-species in larvae with a mouth gape < 900 μm. These results suggest the relative importance of both larval species as primary consumers of the pelagic web in nearshore environments of rocky temperate areas.

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 Diet of Ameerega braccata (Steindachner, 1864) (Anura: Dendrobatidae) from Chapada dos Guimarães and Cuiabá, Mato Grosso State, Brazil

2011 ◽  
Vol 71 (1) ◽  
pp. 189-196 ◽  
Author(s):  
LR. Forti ◽  
ASO. Tissiani ◽  
T. Mott ◽  
C Strüssmann
Keyword(s):  
Body Size ◽  
Niche Breadth ◽  
Prey Availability ◽  
Feeding Habits ◽  
Close Association ◽  
Mato Grosso ◽  
Important Prey ◽  
Phylogenetic Perspective ◽  
Toxic Alkaloids ◽  
Two Populations

The understanding of feeding habits is important for anurans in general, both from an ecological and a phylogenetic perspective. For diurnal poison frogs belonging to the Dendrobatidae family, diet aspects play a crucial role in their defense and survival. Herein, we investigated feeding habits, foraging behaviour, and overall effects of habitat, sex, and body size on the diet of individuals of Ameerega braccata, a poorly known dendrobatid species. Specimens were observed and collected in the type-locality, Chapada dos Guimarães, and in the neighbouring municipality of Cuiabá, both in the State of Mato Grosso, Midwestern Brazil. The most important prey categories for A. braccata were Formicidae, Isoptera, and Acari, whose representatives were caught during active foraging. Individuals from Chapada dos Guimarães population consumed more Acari but fewer Isoptera than individuals from Cuiabá. Despite this, niche breadth values were narrow and similar for the two populations. Individuals from two distinct habitats (campo sujo and cerrado stricto sensu) showed differences in their diet, probably as an effect of differential prey availability. Females consumed more Isoptera than males. The number of prey categories used as food was not influenced by the variation of body size of the target species. However, the abundance and the volume of consumed Acari were statistically correlated with body size. The main results suggest that Ameerega braccata has a narrow niche breadth, as well as a specialised diet in ants, termites, and mites, which reinforces the hypotheses of close association between Acari consumption and the presence of skin toxic alkaloids, already found in other species of Dendrobatidae. Although differences in prey consumption between sexes are uncommon among poisonous frogs, differences in the diet composition between age classes, which probably reduce intraspecific competition, are frequently reported.

Managing Centrarchid Fisheries in Rivers and Streams

2019 ◽  
Keyword(s):  
Community Structure ◽  
Stable Isotope ◽  
Prey Availability ◽  
Prey Selection ◽  
Trophic Position ◽  
Trophic Niche ◽  
Smallmouth Bass ◽  
Spatial Differences ◽  
Stream Size ◽  
Diet Analyses

<em>Abstract.</em>—Prey selection and diet are highly plastic and can vary with temporal and spatial differences in competition or prey availability. This study investigated the possibility that the trophic position of Smallmouth Bass <em> Micropterus dolomieu </em>might change in response to systematic, hierarchical variation in community structure in stream networks. We hypothesized that a shift toward increased insectivory and decreased piscivory would be observed in smaller streams, resulting in a lower trophic position of Smallmouth Bass and reflecting differences in community structure and prey availability. We applied a combination of diet analyses and stable isotope methods to compare prey selection and trophic position of Smallmouth Bass across a range of stream sizes. Stable isotope analyses indicated that Smallmouth Bass trophic position was slightly elevated in smaller watersheds, contradicting our initial hypothesis. However, differences in average trophic position in watershed size categories were small (ranging from 3.6 to 3.8) and of limited ecological significance. Isotopic niche width did not vary among stream size categories, and gut content analyses revealed no differences in frequency of occurrence of fish, crayfish, or insects (larvae and adults). Collectively these results indicate that trophic position, and perhaps trophic niche, of Smallmouth Bass are consistent across hierarchical variation in stream size and habitat.

scholarly journals Trophic niche breadth of pond zooplankton species using stable isotope analysis and the relationship with the abiotic and biotic factors

2019 ◽  
Vol 6 (1) ◽  
pp. 180917 ◽  
Author(s):  
Hideyuki Doi ◽  
Kwang-Hyeon Chang ◽  
Shin-ichi Nakano
Keyword(s):  
Stable Isotope ◽  
Niche Breadth ◽  
Resource Competition ◽  
Feeding Habits ◽  
Zooplankton Biomass ◽  
Trophic Niche ◽  
Zooplankton Species ◽  
Carbon And Nitrogen ◽  
Ecosystem Size ◽  
The Relationship

Zooplankton species have different feeding habits, but the diversity of their food resources and the factors governing them are still largely unknown. We here estimated the differences in the trophic niche breadths of dominant zooplankton species in ponds, using stable isotopes. To understand the differences in trophic niches of different zooplankton species, we measured the carbon and nitrogen stable isotope ratios and calculated the nearest-neighbour distance (NND), and standard deviation of NND (SDNND) of the bi-plot space of stable carbon and nitrogen isotopes in pond zooplankton. We tested the relationship between the NND/SDNND and environmental factors, as well as the zooplankton biomass, using generalized linear models (GLMs). For cladocerans, including Bosmina, Ceriodaphnia and Daphnia, the NNDs were significantly correlated with the biomass, pond morphology (volume and depth), total phosphorous (TP) and fish presence. For copepod species, including Eodiaptomus and cyclopoids, NNDs were significantly correlated with pond morphology, TP and fish presence, but not with biomass. In GLMs of SDNND, significant correlated factors were less than those for NND, and for some species, pond morphology and TP were significantly correlated with SDNND. Here, we found that the NND and SDNND of zooplankton species were related to various factors, including their biomass, predator presence, pond size and water quality. For cladocerans, biomass may be supported by trophic niche breadth, probably because of the consequences of resource competition. Also, predation and ecosystem size may influence trophic niche breadth due to changes in zooplankton behaviours.

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.

Foraging modes of carnivorous plants

2019 ◽  
Vol 66 (1-2) ◽  
pp. 101-112 ◽  
Author(s):  
Aaron M. Ellison
Keyword(s):  
Prey Availability ◽  
Soil Nutrient ◽  
Optimal Foraging Theory ◽  
Foraging Theory ◽  
Carnivorous Plants ◽  
Foraging Strategies ◽  
Nutrient Concentrations ◽  
Future Research ◽  
Single Location ◽  
Foraging Modes

Abstract Carnivorous plants are pure sit-and-wait predators: they remain rooted to a single location and depend on the abundance and movement of their prey to obtain nutrients required for growth and reproduction. Yet carnivorous plants exhibit phenotypically plastic responses to prey availability that parallel those of non-carnivorous plants to changes in light levels or soil-nutrient concentrations. The latter have been considered to be foraging behaviors, but the former have not. Here, I review aspects of foraging theory that can be profitably applied to carnivorous plants considered as sit-and-wait predators. A discussion of different strategies by which carnivorous plants attract, capture, kill, and digest prey, and subsequently acquire nutrients from them suggests that optimal foraging theory can be applied to carnivorous plants as easily as it has been applied to animals. Carnivorous plants can vary their production, placement, and types of traps; switch between capturing nutrients from leaf-derived traps and roots; temporarily activate traps in response to external cues; or cease trap production altogether. Future research on foraging strategies by carnivorous plants will yield new insights into the physiology and ecology of what Darwin called “the most wonderful plants in the world”. At the same time, inclusion of carnivorous plants into models of animal foraging behavior could lead to the development of a more general and taxonomically inclusive foraging theory.

Sign in / Sign up

Export Citation Format

Share Document