Agonistic and Courtship Behaviors in Dionda Diaboli, The Devils River Minnow (Notes) (Report‪)‬

Broadcast spawning is the most ancestral and common mode of reproduction occurring in 60% of North American cyprinids (Johnston and Page, 1992). However, this also is the least studied spawning mode in minnows and it is possible that several subcategories of broadcast spawning exist. For example, while primitive cyprinids like Gila may aggregate in large schools and show no territoriality (Vanicek and Kramer, 1969), Rhinichthys are territorial broadcasters and choosing mates may be possible (Raney, 1940; Mueller, 1984). Little is known about reproductive behavior of Dionda. Dionda serena was observed burrowing eggs into gravel beds (Hubbs, 1951), but most are believed to be broadcasters (Johnston and Page, 1992). Dionda diaboli, the Devils River minnow, is federally listed as threatened (United States Fish and Wildlife Service, 1999). This cyprinid currently occurs in spring-fed waters in the Devils River, and San Felipe and Pinto creeks in western Texas. Although captive breeding has been documented and briefly described, including possible territoriality (Gibson et al., 2004; Gibson and Fries, 2005), a detailed description of reproductive and agonistic behavior is lacking for this species. Information about spawning strategy and group structure could be important in captive-breeding efforts. This study investigated the role of territoriality and potential spawning strategies of D. diaboli in the laboratory.