Turbidity alters pre‐mating social interactions between native and invasive stream fishes

Abstract

1. Environmental degradation can result in the loss of aquatic biodiversity if impairment promotes hybridisation between non-native and native species. Although aquatic biological invasions involving hybridisation have been attributed to elevated water turbidity, the extent to which impaired clarity influences reproductive isolation among non-native and native species is poorly understood. 2. We examined whether turbidity influences intraspecific and interspecific pre-mating social interactions between invasive red shiner (Cyprinella lutrensis) and native blacktail shiner (Cyprinella venusta) from the Upper Coosa River Basin (U.S.A.). 3. We found that the number or duration of conspecific and heterospecific interactions increased under turbid conditions. Additionally, we found evidence indicating that native blacktail shiner females are especially likely to interact with invasive red shiner males due to species-and sex-specific responses to turbid conditions. 4. These findings suggest that elevated turbidity can increase pre-mating social interactions between native and invasive species, which could result in greater hybridisation and promote the genetic assimilation of native species following species introductions. Thus, integrating knowledge of species behaviour into conservation and management planning can help deter the establishment and spread of invasive species.

Rapid movement and instability of an invasive hybrid swarm

“…; Ward and Blum ; Glotzbecker et al. ), little information has been available on the stability and evolution of the swarm over time. Empirical analysis of phenotypic and genetic clines across hybrid swarms over time is arguably a more reliable method for assessing stability, including movement and expansion (Blum , ; Dasmahapatra et al.…”

“…The potential for loss of native biota through biological invasions involving hybridization has risen as human-mediated introduction, and invasions of non-native species have increased over time (Epifanio and Philipp 2000;Allendorf et al 2001;Crispo et al 2011). Although prior studies examining the C. lutrensis x C. venusta hybrid swarm in the Upper Coosa River basin (Walters et al 2008;) have characterized the formation of the swarm, as well as the spatial extent and factors contributing to hybridization Glotzbecker et al 2015), little information has been available on the stability and evolution of the swarm over time. Empirical analysis of phenotypic and genetic clines across hybrid swarms over time is arguably a more reliable method for assessing stability, including movement and expansion (Blum 2002(Blum , 2008Dasmahapatra et al 2002;Buggs 2007).…”

“…Evidence of contraction and expansion suggests that the swarm may fluctuate in response to temporal shifts in extrinsic drivers of hybridization such as impairment of water quality characteristics that influence reproductive isolation or that result in conditions that favor hybrids (Guo 2014). Prior work indicates that shifts in either turbidity or chemical contamination could influence the amount and distribution of hybridization between native C. venusta and invasive C. lutrensis over time Glotzbecker et al 2015).…”

Biodiversity loss through speciation collapse: Mechanisms, warning signals, and possible rescue*

“…Glotzbecker et al. () showed that elevated turbidity can weaken sexual selection by impairing species recognition between native and invasive stream fishes, thus resulting in formation of hybridization, but they neglected the impact of water turbidity on fish ecology.…”

“…The formation of hybrids is thought to have resulted from elevated water turbidity and habitat destruction following the introduction of crayfish Taylor et al 2006). Indeed, experimental studies show that impaired water clarity can alter the premating mechanism of sexual selection to reduce reproductive isolation (Sundin et al 2010;Glotzbecker et al 2015).…”