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Content with tag trophic interactions .

The diet of the bottlenose dolphin described by stomach content and stable isotope analyses

The ecological role of species can vary among populations depending on local and regional differences in diet. This is particularly true for top predators such as the bottlenose dolphin, which exhibits a highly varied diet. Local dietary assessments are therefore critical to fully understand the role of this species within marine ecosystems. Here, stomach content analyses and stable isotope analyses were combined to describe bottlenose dolphins diet in the Gulf of Cadiz.

Feeding ecology and trophic relationships of pelagic sharks and billfishes

Large pelagic fishes are top predators inhabiting the water column of the tropical and subtropical Pacific Ocean. They are highly migratory organisms, and for Ecuadorian fisheries, they also represent important economic resources. Four shark species, Prionace glauca, Isurus oxyrinchus, Carcharhinus falciformis and Alopias pelagicus, and 3 billfish species, Xiphias gladius, Istiophorus platypterus and Makaira nigricans were sampled, in order to gain understanding of their feeding ecology and...

The ecological role of uncommon and endangered elasmobranch

Deficiencies in basic ecological information on uncommon and endangered elasmobranch fishes impair the assessment of their ecological role in marine ecosystems. In this study, we examined the feeding ecology (diet composition and trophic level) and trophic relationships of several elasmobranchs species present in the western Mediterranean Sea.

Invasive species globally cause the decline of aquatic communities

The introduction of invasive species, which often differ functionally from the components of the recipient community, generates ecological impacts that propagate along the food web. This review aims to determine how consistent the impacts of aquatic invasions are across taxa and habitats. To that end, we present a global meta-analysis from 151 publications, covering a wide range of invaders (primary producers, filter collectors, omnivores and predators), resident aquatic community components...

Fecal nitrogen in European rabbit ecological studies

Measuring the quality of the nutritional resources available to wild herbivores is critical to understanding trophic regulation processes. However, the direct assessment of dietary nutritional characteristics is usually difficult, which hampers monitoring nutritional constraints in natural populations. The feeding ecology of ruminant herbivores has been often assessed by analyzing fecal nitrogen (FN) concentrations, although this method has been less evaluated in other taxa. This study...