Nuclear-follower foraging associations among Characiformes fishes and Potamotrygonidae rays in clean waters environments of Teles Pires and Xingu rivers basins, Midwest Brazil

Abstract

During under and overwater observations were recorded nuclear-follower foraging associations among three species of characiform fishes - Chalceus epakros, Hemiodus semitaeniatus and Hemiodus unimaculatus - and a freshwater stingray species - Potamotrygon orbignyi - in the Teles Pires and Xingu rivers basins, Midwest Brazil. The teleost fishes were observed closely following the stingrays during the behavior of stirring the substrate to uncover invertebrates, which cause discrete sediment clouds. Apparently this sediment perturbation attracts the fishes that approached the foraging stingrays to feed on small preys and other food types exposed this way. This is a typical example of a commensal relationship in which one participant is benefited while the other is unaffected, and represents the second published record of nuclear-follower feeding association between potamotrygonid rays and teleost fishes, demonstrating the potential of naturalistic studies in discovering new interactions involving species of freshwater fish.

Multi‐species fish foraging associations during tool use by the graphic tuskfish Choerodon graphicus (De Vis 1885) (Labridae)

“…The number of individuals and species may change over time (Itzkowitz, 1977), and nuclear and attendant species may also change the way they interact during ontogeny (Itzkowitz, 1974; Strand, 1988). Locations include a variety of marine (de Araújo et al., 2009; Aronson & Sanderson, 1987; Baird, 1993; Craig & Erisman, 2010; Gerhardinger et al., 2006) and freshwater (Garrone Neto & Carvalho, 2011; Sabino et al., 2016; Teresa et al., 2014) environments. These diverse multi‐species fish foraging associations may be important to the ecology of coral reefs.…”

Juvenile silver grunter Mesopristes argenteus shift benthic objects to access food

“…There are also a number of fishes (and other fauna) in both marine and freshwater systems that are known to disrupt the benthos during feeding and are followed by fish that stand to gain from prey being flushed from hiding (Baker & Foster, ; Sazima et al, ; Teresa et al, ). In the past decade, there has been a steady increase in scientific interest in this form of behavioural interaction within freshwater ecosystems and notably in a tropical South American context (Azevedo et al, ; Costa‐Pereira, ; Garrone Neto & Carvalho, ; Sabino et al, ; Teresa et al, , ). This literature primarily addresses how disrupting soft benthos has the capacity to alter stream fish assemblages by exposing benthic prey for both nuclear and follower fishes, with ramifications for fish assemblage composition specifically as a function of conditions favouring particular nuclear and follower species (Baker & Foster, ; Sabino et al, ; Teresa et al, , ).…”