Does body and fin form affect the maneuverability of fish traversing vertical and horizontal slits?

Abstract

SynopsisThe purpose of this study was to determine if body and fin form affected the maneuverability of teleostean fishes as measured by their ability to negotiate simple obstacles. Obstacles were vertical and horizontal rectangular slits of different widths, for which width was defined as the minimum dimension of a slit irrespective of slit orientation. Performance was measured as the smallest slit width traversed. Three species with different body and fin patterns were induced to swim through slits. Species tested were; goldfish Carassius auratus with a fusiform body, anterio-ventral pectoral fins and posterio-ventral pelvic fins; silver dollars Metynnis hypsauchen with the same fin configurations but a gibbose body; angelfish Pterophyllum scalare with a gibbose body and anterio-lateral pectoral fins. Minimum slit widths negotiated were normalized with the length of various body dimensions: total length, maximum width, span at the pectoral fins, and volume '" (numerically equal to mass 'I3). Goldfish had the poorest performance, requiring the largest slit widths relative to these body dimensions. No consistent patterns in performance were found for silver dollars vs. angelfish. There were no differences among species in the ratio of minimum vertical slit width negotiated to that for horizontal slits, indicating fish were equally able to control posture while swimming on their sides. There were also no consistent patterns in the times taken to transit slits. Although the deep-bodied fish were able to maneuver through smaller slits, the most striking result is the similarity of minimum slit widths traversed in spite of the large variation in body form. Body form and fin plan may be more important for maneuvering and posture control during sub-maximum routine activities.

Ecomorphology and use of food resources: inter- and intraspecific relationships of fish fauna associated with macrophyte stands

“…Nevertheless, they showed larger anal fins, which implies in greater maneuverability and stabilization of movement (Breda, 2005). Maneuverability is defined as the ability of organisms to perform quick small-angled maneuvers (Webb et al, 1996). Thus, species with these characteristics exhibit a superior performance in the exploitation of structurally complex habitats.…”

Diet and ecomorphological relationships of an endemic, species-poor fish assemblage in a stream in the Iguaçu National Park

“…The armored catfish A. mullerae, with a depressed body (benthic ecomorphotype), has a long caudal peduncle and well-developed paired fins, which provide stability in riffles (Bernoulli effect) (Webb et al, 1996;Breda et al, 2005;Oliveira et al, 2010;Pagotto et al, 2011). Together with these adaptations, its mouth with sucking lips favors the uptake of debris and algae from the streambed.…”

Ecomorfologia de locomoção de peixes com enfoque para espécies neotropicais

“…Karr e James (1975) introduziram o termo ecomorfologia. Além desses, outros ecólogos passaram a responder questões relacionadas ao conceito de nicho, estrutura de comunidades, competição, partição de recursos e diversidade de táxons a partir de características fenotípicas (Gatz, 1979;Felley, 1984;Watson e Balon, 1984;Wikramanayake, 1990;Winemiller, 1991;Douglas e Mathews, 1992;Hugueny e Pouilly, 1999;Bellwood et al, 2002;Wainwright et al, 2002;Langerhans et al, 2003;Pouilly et al, 2003). No Brasil, destacam-se Beaumord (1991Beaumord ( , 2000, Barrela et al (1994), Catella e Petrere (1998), Freire e Agostinho (2001) e Breda (2005).…”

“…A importância da locomoção para estudos ecomorfológicos está no fato de que o tipo de natação utilizada tem implicações diretas sobre o uso de hábitat (Wainwright et al, 2002), as interações bióticas (Werner, 1977) e o forrageamento (Webb, 1984). Dessa forma, torna-se imprescindível o conhecimento de aspectos morfo-funcionais relacionados à locomoção.…”