scholarly journals Desert pumpkinseed: diet composition and breadth in a Moroccan river

Author(s):  
Christos Gkenas ◽  
Maria Filomena Magalhães ◽  
Nazaret Campos-Martin ◽  
Filipe Ribeiro ◽  
Miguel Clavero

The widely invasive North American pumpkinseed sunfish, Lepomis gibbosus, is currently established in desert rivers in Morocco. The success of pumpkinseed in novel ecosystems has been associated with its generalist diet, but this trait remains unevaluated in arid regions. Desert rivers are harsh environments with limited water and prey availability which may adversely constrain the diet of fish. Here we studied the diet of pumpkinseed across 4 sites in the Draa River, embracing a 450 m elevational gradient covering from extremely dry lowlands to relatively humid highlands. We described pumpkinseed diet through the analysis of stomach contents of 82 individuals, collected in the fall of 2013. Pumpkinseed diet was dominated by Chironomidae in dry lowlands, while Ephemeroptera, Heteroptera, Trichoptera and Odonata were relevant prey in more humid highlands. Population diet breadth expanded with elevation, but individual specialization in diet was low among all sites. Our results highlight considerable changes in diet composition and breadth with aridity, suggesting that feeding plasticity and use of exclusive, locally abundant prey rather than generalized feeding may be associated with the success of pumpkinseed in most arid areas in desert rivers.

2020 ◽  
Vol 32 ◽  
Author(s):  
Igor David Costa ◽  
Ronaldo Angelini

Abstract Aim In this paper, we compared the diet composition of the South American silver croaker, Plasgioscion squamosissimus in preserved and impacted areas (agrarian land use) of an Amazonian river. Our objective was to quantify the plasticity in diet across different habitats and evaluate the importance of a carnivorous generalist species as an environmental indicator based on its feeding variation. Methods We analysed the stomach contents of 135 individuals and compared the trophic level of P. squamosissimus and the source of ingested food items in the impacted and non-impacted habitats. Results The trophic level values in both areas were similar. In both areas, P. squamosissimus used a wide variety of food items, consuming mainly fish and invertebrates of autochthonous origin. However, in terms of composition of food items, small pelagic fish and autochthonous items were more frequently consumed in the preserved area, while in the impacted area fish and benthic invertebrates were predominant in the diet. Conclusions Our gut analysis suggests plasticity in P. squamosissimus diet across varying areas, which point to the ability of P. squamosissimus to modify their diet in the impacted situation, utilizing more benthic material on impacted area in order to maintain a similar trophic position.


2020 ◽  
pp. 169-175
Author(s):  
G. Michelin ◽  
K. Ceron ◽  
D. J. Santana

Prey availability in an environment may change seasonally and these changes should be considered as determinant factors for the diets of anurans. Scinax species are generalist predators that feed on arthropods, but data concernning their diet in relation to prey availability are lacking. In this study, we describe the diet of Scinax fuscomarginatus by evaluating its possibly generalist diet related to prey availability in its environment. We studied the diet of Scinax fuscomarginatus by analysing the stomach contents of 48 individuals captured in the Campo Grande municipality, Mato Grosso do Sul state, Brazil. We found eight prey categories, the most common and most representative being Hemiptera. The selectivity index of the two most important prey varied inversely between dry and wet seasons. Prey availability also varied between seasons. These results suggest a temporal pattern in prey composition and in the diet of Scinax fuscomarginatus.


2016 ◽  
Vol 14 (3) ◽  
Author(s):  
Santiago A. Barbini ◽  
Luis O. Lucifora

ABSTRACT The eyespot skate, Atlantoraja cyclophora, is an endemic species from the southwestern Atlantic, occurring from Rio de Janeiro, Brazil, to northern Patagonia, Argentina. The feeding habits of this species, from off Uruguay and north Argentina, were evaluated using a multiple hypothesis modelling approach. In general, the diet was composed mainly of decapod crustaceans, followed by teleost fishes. Molluscs, mysidaceans, amphipods, isopods, lancelets and elasmobranchs were consumed in lower proportion. The consumption of shrimps drecreased with increasing body size of A. cyclophora. On the other hand, the consumption of teleosts increased with body size. Mature individuals preyed more heavily on crabs than immature individuals. Teleosts were consumed more in the south region (34º - 38ºS) and crabs in the north region (38º - 41ºS). Shrimps were eaten more in the warm season than in the cold season. Prey size increased with increasing body size of A. cyclophora , but large individuals also consumed small teleosts and crabs. Atlantoraja cyclophora has demersal-benthic feeding habits, shifts its diet with increasing body size and in response to seasonal and regional changes in prey availability and distribution.


2015 ◽  
Vol 17 (1) ◽  
pp. 216 ◽  
Author(s):  
B. ZORICA ◽  
V. ČIKES KEČ ◽  
O. VIDJAK ◽  
I. MLADINEO ◽  
D. EZGETA BALIČ

We examined the stomach contents of two of the most economically and ecologically important small pelagic fish species, the sardine, Sardina pilchardus and the anchovy, Engraulis encrasicolus, obtained monthly from commercial purse-seine catches operating on Croatian fishing grounds during a one-year period (January–December, 2011). Both species generally showed a similar diet, with copepod and decapod larvae as dominant prey groups. The composition of anchovy and sardine stomach contents was not size- or sex-related, but throughout the year, a significant difference in diet composition was observed for each species as well as between species. Two gastrointerstinal helminths; the digenean Parahemiurus merus and nematode Hysterothylacium aduncum, were recorded during the stomach content analysis. Differences in population dynamics between the two parasites are congruent with differences in the prey composition of sardine and anchovy, reflecting fine-tuned interactions in the trophic web between parasites and intermediate or paratenic hosts included in the sardine and anchovy diet.


Author(s):  
Alexander Didenko ◽  
Igor Buzevych ◽  
Yuriy Volikov ◽  
Svitlana Kruzhylina ◽  
Alexander Gurbyk

Population dynamics and feeding patterns of invasive Knipowitschia caucasica were studied in the littoral zone of the lower Stugna River. The abundances of this goby showed significant inter-annual and seasonal fluctuations. The studied population of K. caucasica was represented by two age groups (0 and I). Fish die after their first breeding season. In total, 58 prey items were identified in the diet of K. caucasica at the sampling site. The most abundant prey were copepods and cladocerans, while the most frequently encountered prey were copepods and chironomid larvae. Copepods were represented mainly by Cyclopoidae. Cladocerans included 21 taxa, among which the most abundant were Diaphanosoma sp., Acroperus harpae, and Disparalona rostrata; chironomids included 22 taxa, among which the most abundant was Cricotopus sylvestris. The diet composition showed seasonal dynamics, where copepods predominated in January to April and in August-September, chironomid larvae were especially important in May to July, while cladocerans were most important in November-December. The relatively high diversity of both phytophilous and open-bottom-dwelling prey organisms in the stomach contents of K. caucasica indicates that this species fed on a large variety of benthic habitats including among macrophytes and open areas.


1990 ◽  
Vol 2 (1) ◽  
pp. 23-28 ◽  
Author(s):  
N.J. Gales ◽  
N.T.W. Klages ◽  
R. Williams ◽  
E.J. Woehler

The diet of the emperor penguin Aptenodytes forsteri (Gray) in Amanda Bay, Princess Elizabeth Land, Antarctica, was studied by analysis of adult stomach contents during part of the chick-rearing period from August to October 1986. The penguins consumed almost entirely fish, mainly Pleuragramma antarcticum (Boulenger) (78% by number and 78% by mass). Other fish species, cephalopods and crustaceans were minor components. These results and those of the only other two, geographically distinct, quantitative studies of the diet of emperor penguins suggest that the diet of this species varies through the effects of local topography and hydrology on prey availability.


Author(s):  
Manuela Bassoi ◽  
Eduardo R. Secchi ◽  
Daniel Danilewicz ◽  
Ignacio B. Moreno ◽  
Roberta A. Santos ◽  
...  

Abstract The franciscana dolphin (Pontoporia blainvillei) is a coastal dolphin endemic to the western South Atlantic Ocean. The dolphin is listed as vulnerable in the IUCN Red List, with incidental catches in gillnet fisheries the greatest conservation concern for this species. Insights into the feeding habits of this dolphin are essential to understand its distribution, movements and use of habitat, which are fundamental for effective management of the species. The feeding habits of franciscana dolphins were investigated from analyses of stomach contents of animals incidentally caught by two fishing operations from southern and northern regions of the southern Brazilian coast. In this study we investigate the existence of intrapopulation (sexual maturity and sex-related) variation in the diet of the franciscana dolphin, evaluating the spatial (northern and southern geographic areas) and seasonal influences. The analyses were based on Linear and Generalized Linear Models (LM and GLM). The majority of identified prey species were bottom-dwelling teleosts and the squid Doryteuthis sanpaulensis. The most important prey differed spatially and seasonally between northern and southern regions of the study area, and our results revealed significant differences between sexes and sexual maturity stages, mainly related to prey species sizes. This variation might indicate differences in prey selection, availability or habitat use patterns among these groups. In any case, these dietary differences are likely to minimize intraspecific competition for food resources, and/or indicate spatio-temporal variation in prey availability.


2017 ◽  
Vol 64 (5) ◽  
pp. 603-613 ◽  
Author(s):  
Gregorio Moreno-Rueda ◽  
Elena Melero ◽  
Senda Reguera ◽  
Francisco J Zamora-Camacho ◽  
Inés Álvarez-Benito

2017 ◽  
Vol 17 (3) ◽  
Author(s):  
Mariana S. Lopes ◽  
Ricardo S. Bovendorp ◽  
Gilberto José de Moraes ◽  
Alexandre Reis Percequillo ◽  
Jaime Bertoluci

Abstract We describe here the diet of the microhylid frog Chiasmocleis leucosticta based on the stomach contents of 72 individuals (47 males and 25 females) collected in pitfall traps at the Reserva Florestal de Morro Grande, state of São Paulo, southeastern Brazil. We identified 1,981 food items distributed in 13 prey categories of arthropods, mainly ants, mites and collembolans. Formicidae was the most abundant and frequent prey category, including 16 genera from seven subfamilies, and data on ant availability in the habitat suggest that C. leucosticta selects ants actively. The second main prey category was Acari, predominantly represented by mites of the suborder Oribatida. This is the first work identifying mites to the family level in the diet of a Microhylidae. There was no statistical difference between males and females regarding diet composition.


Sign in / Sign up

Export Citation Format

Share Document