Trends in Studies of Nonnative Populations: Invasions in the Upper Parana River Floodplain

A systematic review was conducted to identify trends and gaps in studies concerning nonnative populations in a neotropical floodplain and identify which population ecology topics has been predominant among studies in such floodplains. The large majority of the articles were field observational studies based on nonnative fish populations. A focus on ecological interactions, in particular competition and predation, was predominant in these studies. Hypotheses related to environmental filters and biotic resistance were used most frequently to support studies on river the floodplain, but many studies not addressed the invasion theory. Impoundment was the introduction vector associated with the largest number of studies of nonnative populations. We present conceptual aspects that may guide future studies on nonnative population ecology and inform conservation policies in floodplain ecosystems.