Spawning Behavior and Ecology of Shovelnose Sturgeon in an Artificial River

We observed the spawning and mating behaviors of shovelnose sturgeon in an artificial river. We described the behavioral characteristics of sturgeon during spawning and determined the influence of flow and substrate on spawning behavior. Spawning trials were performed under varying flow, substrate, and temperature conditions. Sturgeon spawned at temperatures from 16-22°C, water velocity from 9-69 cm/s, and over gravel and cobble. When spawning, males and females released gametes in immediate proximity to each other, close to (~5 cm) or on the substrate, and in a quivering fashion. A mating was brief, lasting an average of 1.8 s. The spawning duration for male and female shovelnose sturgeon varied from 3 to 18 h. The number of spawning events per individual varied, but successful and unsuccessful attempts to mate was as high as 75 total attempts for an individual. We present an analysis comparing spawning habitat used to habitat available. The results from this project could provide useful information to managers of regulated rivers aiming to manipulate the hydrograph to promote spawning, aid in constructing artificial spawning habitat, and help develop conservation propagation methods that allow more natural mating and rearing conditions.