scholarly journals Feeding ecology of Rivulus luelingi (Aplocheiloidei: Rivulidae) in a Coastal Atlantic Rainforest stream, southern Brazil

2010 ◽  
Vol 8 (4) ◽  
pp. 813-818 ◽  
Author(s):  
Vinícius Abilhoa ◽  
Jean Ricardo Simões Vitule ◽  
Hugo Bornatowski

Feeding habits of the killifish Rivulus luelingi collected in a black water stream of the Coastal Atlantic Rainforest in southern Brazil were investigated. Eight samplings were made between April 2003 and January 2004. The diet, assessed through a similarity matrix with the estimated contribution values of food items, included microcrustaceans, aquatic immature insects (larvae and pupae), aquatic adult insects, terrestrial insects, insect fragments, spiders, and plant fragments. Differences in the diet according to temporal variations (months) were registered, but changes related with size classes evaluated and high/low precipitation period were not observed. The species presented an insectivorous feeding habit, and its diet in the studied stream was composed of autochthonous (mainly aquatic immature insects) and allochthonous (mainly insect fragments) material.

2009 ◽  
Vol 7 (3) ◽  
pp. 415-420 ◽  
Author(s):  
Vinícius Abilhoa ◽  
Hugo Bornatowski ◽  
Gislaine Otto

Feeding habits of the characin Hollandichthys multifasciatus were investigated. Samplings were made between March 2004 and February 2005 in two black water streams of the coastal Atlantic rainforest in southern Brazil. The diet, evaluated by qualitative and quantitative methods, included aquatic and terrestrial insects, decapods, oligochaetes, plants and spiders. Large individuals feed mainly on plants, terrestrial insects, and spiders, whereas small fish feed basically on plants and oligochaetes. The species showed an omnivorous feeding habit, and its diet was composed of autochthonous (mainly oligochaetes) and allochthonous (plants and terrestrial insects) material.


2009 ◽  
Vol 7 (2) ◽  
pp. 257-266 ◽  
Author(s):  
Luciano Lazzarini Wolff ◽  
Vinícius Abilhoa ◽  
Flavia Sant'Anna Rios ◽  
Lucélia Donatti

This study described the feeding habits of the characin Astyanax aff. fasciatus. The diet compositions of specimens from two sites (A and B) on a river in Southern Brazil were compared according to the size of individuals and seasonal period. The collections were performed monthly from March 2005 to February 2006, where the stomach contents of 290 specimens were assessed. Food items for A. aff. fasciatus were basically composed of plants and insects, especially leaf fragments, seeds, fruits, filamentous algae, aquatic and terrestrial insects and insect fragments. At site A, the most common items were insect and plant fragments. Conversely at site B, plant fragments were more representative. In general, all items of animal origin showed the highest feeding index values at site A, whereas at site B detritus and grass items were more abundant. The composition of items varied seasonally, with higher diversity of items being recorded during the spring at both sites. Smaller individuals preferred items of animal origin, while the larger ones consumed mainly items of plant origin. According to its size, A. aff. fasciatus in this study may be considered a species with insectivorous tendencies when immature or herbivorous tendencies when adult. Nevertheless, its feeding habits may be flexible according to resource availability, showing wide ontogenetic, besides spatial and temporal variation.


2005 ◽  
Vol 26 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Otávio Marques ◽  
Paulo Hartmann

AbstractFeeding habits and habitat use of the colubrid snakes Philodryas olfersii and P. patagoniensis in southern Brazil are presented here. Philodryas olfersii and P. patagoniensis are sympatric in the study area and both dwell in open and forested areas. Specimens preserved in collections and observations of snakes in the field yielded the data. Both species are diet generalists, feeding on small vertebrates, mainly frogs. Philodryas patagoniensis has a broader diet, a less variable frequency of food items, and fed on heavier prey than P. olfersii. Seasonal variation in diet occurs in both species. The semiarboreal Philodryas olfersii is more slender and has a longer tail than the terrestrial P. patagoniensis, characters that may reflect differences in microhabitat use. There are a strong relationship between habitat use and frequency of a given food type. Differences in the use of food resources between P. olfersii and P. patagoniensis seem to reflect differences in foraging microhabitats used by each species.


2007 ◽  
Vol 5 (1) ◽  
pp. 69-74 ◽  
Author(s):  
André L. Netto-Ferreira ◽  
Míriam P. Albrecht ◽  
Jorge L. Nessimian ◽  
Érica P. Caramaschi

The silver hatchetfish Thoracocharax stellatus is one of the approximately 200 fish species recorded for the upper rio Tocantins, in the region where it was impounded by the Serra da Mesa hydroelectric dam. Analysis of the stomach contents of 88 specimens revealed a diet consisting almost entirely of insects (99.6%), most of which were terrestrial (87.6%). Ants, beetles, and mayflies were the main food items. Dawn and dusk seemed to be the periods of highest foraging activity for T. stellatus. As a specialist on terrestrial insects, this species has a close connection with the region near the river bank, where prey is provided from the associated riparian vegetation. Despite the impoundment and depletion of the land-water ecotone observed in later stages of reservoir formation, no significant changes in the diet of the few remnant specimens were recorded, which seems to indicate little feeding flexibility. Thus, feeding seemed to be an overriding factor for the displacement of this species after river impoundment.


2010 ◽  
Vol 8 (1) ◽  
pp. 179-182 ◽  
Author(s):  
Rosana Mazzoni ◽  
Raphaella Rangel da Silva Araújo ◽  
Gardênia Carolina Tosta dos Santos ◽  
Ricardo Iglesias-Rios

In the present work, we determined the relative importance of allochthonous and autochthonous food items as well as seasonal and ontogenetic variation in the feeding habits of Phalloceros anisophallos from córrego Andorinha, Ilha Grande. Quantitative analysis, based on alimentary index (IAi) and food volume (Vo), revealed that P. anisophallos fed on detritus, autochthonous algae (diatoms, unicellular and filamentous Chlorophyceae algae), autochthonous animals (aquatic insect larvae: Trichoptera, Chironomidae and other Diptera) and allochthonous animals (terrestrial insects: Hymenoptera). Ontogenetic variations were recorded for the consumption of each food category. Adults used a larger amount of algae and detritus, and juveniles used a higher amount of animal items. Significant differences in intestinal coefficient between adult and juvenile individuals corroborated the ontogenetic differences in feeding behavior. IAi values of each consumed food category did not vary between the rainy and dry seasons, but mean detritus Vo differed between seasons and was significantly (Anova, p<0.01) greater during the dry season.


2006 ◽  
Vol 63 (7) ◽  
pp. 1297-1303 ◽  
Author(s):  
Alexander V. Orlov ◽  
Yuri V. Gerasimov ◽  
Oleg M. Lapshin

Abstract An underwater survey was conducted in the Louvenga River to investigate the behaviour and distribution of juvenile Atlantic salmon, Salmo salar L., and the adaptation of cultured fish to the natural environment. The food and feeding habits of 34 wild and 44 cultured parr released from the Kandalaksha hatchery were also studied. The cultured salmon fed mostly in the bottom 15 cm of the water column in current velocities of 0.2–0.35 m s−1. In contrast to wild fish, when cultured fish moved away from these areas and into areas with higher current velocities (average speeds of 0.52 m s−1) and lower drift density (2.66 particles m−3), they did not show a tendency to return to slower moving water. The diet of cultured parr was made up of benthic invertebrates (20%), terrestrial insects (32%), and drift items (33%), but these proportions were different in the diet of wild parr (2%, 24%, and 67%, respectively), with drift items predominating. The mean quantity of food per stomach indicated that the wild parr were feeding more actively than cultured parr. Invertebrates made up 3% of items in the drift, with the remaining 97% being exuvia of aquatic and terrestrial insects, algae, and various plant remains. Poor quality food items were found in 13% and 25% of the stomachs of wild and cultured parr, respectively, demonstrating that the cultured parr were less able to differentiate food items in the water column and made 20–30% more false feeding attempts than wild fish. The cultured parr were also more aggressive in terms of the frequency of aggressive interactions and reacted to each other at greater distances than wild fish. Thus, wild parr were able to optimize their feeding conditions by choosing habitats with preferred sizes of food items, higher densities of drift items, and current velocities that allowed them to maintain station and to feed more effectively. Conversely, cultured parr usually occupied suboptimal areas.


2021 ◽  
Vol 29 (2) ◽  
pp. 69-85
Author(s):  
D.A Kouamé Ouanko ◽  
Y.A Konan ◽  
T.M Kamelan ◽  
B.G Gooré ◽  
Z.M Gogbé

Food and feeding habits of two Nothobranchiidae species, Epiplatys chaperi sheljuzhkoi (Poll, 1953) and Nimbapanchax petersi (Sauvage, 1882) from Banco River were investigated between January and December 2016. Stomach contents of 119 and 397 individuals of E. sheljuzhkoi and N. petersi were respectively analyzed, ranging in size from 13 and 55 mm, 11 and 48 mm standard Length, respectively. Formicidae being terrestrial insects, constituted the main prey (RI>50) of both species, and aquatic insect larvae (Hydrophilidae and Chironomidae) were secondary or accessory preys. The food items in stomach showed a small spectrum in E. sheljuzhkoi than N. petersi but differences were not significant (Chi-square, p>0.05). Diet composition of both species showed little variation according to seasons, sampling zones and size groups (Anova, p>0.05). However, a decreasing trend in terrestrial insects and an increase of other preys in stomach contents has been observed from upstream to downstream. For ontogenic variation, large specimens group fed much more on aquatic insect larvae, fish scales and macrophytes than small size group. This work indicated that both species fed on a small range of prey items dominated by insects in Banco River and could be considered strict insectivorous predators. This work concludes that both species have similar diets and the canopy cover of Banco forest plays an important role in the feeding and conservation of these species. Key words: Epiplatys, Nimbapanchax, canopy cover, diet, terrestrial insects, Formicidae, predator.


2021 ◽  
Vol 11 (2) ◽  
pp. 10-18
Author(s):  
Farah Akmal Idrus ◽  
Fazimah Aziz ◽  
Adriana Christopher Lee

Length-weight relationship (LWR), condition factor (K) and feeding habits of Coilia dussumieri, Nemapteryx nenga and Nibea soldado from Santubong Estuary, Sarawak, Malaysia were reported in the present study. The sampling was conducted during the non-monsoon season and monsoon season from April to November 2017 at Buntal, Penambir and Demak rivers using three-layered gillnets. A total of 182 fish samples were caught and measured for the total length and body weight. Then, the data were analysed by the equations for LWR and K. The feeding behaviour analysis was carried out using Relative Gut Index (RGI) and Frequency of Food Occurrence method. The log-transformed regression showed that most of the fishes exhibited negative allometric. K showed a significant difference between seasons. The RGI values of the fishes showed that they were carnivorous. The highest frequency of food occurrence in both seasons was gastropods (94-95 %) and the food items were found to be more variable during monsoon season (gastropods insect, worms, fish, asteroidea, phytoplankton and bivalve). The b value is an exponent to measure the growth pattern of fish and in this study, the b values were in the expected range of 2.5-3.5 and not affected by seasonal variation. The K values suggesting that most of the species were surviving well in the river and was influenced by seasonal change. The RGI and frequency of food occurrence showed that all fish in this study species were carnivorous with more variability in food was observed during the monsoon season. The data of this study are important for a sustainable fisheries management in this area.


SCISCITATIO ◽  
2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Djoko Rahardjo ◽  
Vinsa Cantya Prakasita ◽  
Marlen Aviati Sarah Pepiana

Malaria is known as an endemic disease that often causes death in Indonesia, especially in Papua. The malaria cases control in Papua has not been carried on based on data studies, therefore bionomic of Anopheles sp is important to be studied. Bionomics data are consisted of breeding places, resting places and feeding habits are from direct observation. Interviews and questionnaires were conducted to gain information about respondent behavior. Descriptive and qualitative data were then analyzed. The breeding places of Anopheles sp. were mostly found in swampy areas. Based on the feeding habit, the feeding activity of Anopheles sp. inside the house has only one biting peak at 23.00-02.00 WIT, while outside the house, biting peaks occurred at 21.00-22.00 WIT and 00.00-01.00 WIT. Resting place data shown that Anopheles sp. mostly found in piles of clothes and shoe racks. Recorded factors that affect mosquitos bionomics are temperature, humidity, salinity, pH, community behavior, and the presence of livestock. Environmental factors (temperature, humidity, salinity, and pH), habitual behavior of host (3M action, the habit of using insect repellent, mosquito repellent, and mosquito nets), the presence of livestock, and the type of bait blood type affect mosquito activity.


Sign in / Sign up

Export Citation Format

Share Document