In this paper, we will present an online operational monitoring and Trophic State Index (TSI) estimation system of lakes in general. Our work is related to the ecological state of all lakes (including instilling rivers) that would have use of the system by receiving real time statistics. The study aims to present the system potential for instance remote and fast information management, detailed...

Trophic levels are critical for synthesizing species' diets, depicting energy pathways, understanding food web dynamics and ecosystem functioning, and monitoring ecosystem health. Specifically, trophic levels describe the position of species in a food web, from primary producers to apex predators (range, 1-5). Small differences in trophic level can reflect large differences in diet. Although tr...

Trophic cascades triggered by fishing have profound implications for marine ecosystems and the socioeconomic systems that depend on them. With the number of reported cases quickly growing, key features and commonalities have emerged. Fishery-induced trophic cascades often display differential response times and nonlinear trajectories among trophic levels and can be accompanied by shifts in alte...

The widespread African clawed frog (Xenopus laevis) occurs in sympatry with the IUCN Endangered Cape platanna (Xenopus gilli) throughout its entire range in the south-western Cape, South Africa. In order to investigate aspects of the interspecific competition between populations of X. laevis and X. gilli, an assessment of their niche differentiation was conducted through a comprehensive study o...

We investigated relationships between oceanographic processes, prey availability, diet and the reproductive success of the marbled murrelet Brachyramphus marmoratus (Alcidae), a federally threatened seabird. We predicted that cooler ocean conditions (which increase primary productivity in this eastern boundary upwelling system) should result in heightened prey availability and hence higher repr...

Carpenter et al. (1998) investigated how nutrients (i.e., phosphorus [P] input), dissolved organic carbon (DOC), and grazing are related to phytoplankton biomass and production in four manipulated lakes intensely sampled during five summers. Multivariate probability distributions of algal biomass and production were constructed for varying data on P input rates, DOC, and grazer length, where DO...

Fish diets were analyzed to evaluate the dynamic trophs of the fish community in the Churince wetland system of the Cuatro Ciénegas, where the fauna consists of nine species: endemic, native and introduced. In nine sampling events (between February 2011 and May 2014) 556 specimens of all nine species were collected. Stomach contents were analyzed and the Relative Importance Index (IRI) was calc...

The Panama grunt is an abundant and commercially important species in the southeastern Gulf of California, but the research undertaken on this species is scarce despite its ecological and economic importance. We studied the feeding habits of Panama grunt through stomach content analyses as a first step towards understanding the biology of this species in the study area. Our results indicate tha...

There is a significant relationship between the intestine length (Y) and total body length (X) for 11 species of freshwater fish (Y = 0.08X1.42). Sufficient variation exists about this relationship to indicate important differences among the species' diets. The diets for each species, ranked on a Trophic Index scale determined from literature data, are negatively rank order correlated with the ...