Use of laboratory studies to develop a dispersal model for Missouri River pallid sturgeon early life intervals

Abstract

Summary Understanding the drift dynamics of pallid sturgeon (Scaphirhynchus albus) early life intervals is critical to evaluating damming effects on sturgeons. However, studying dispersal behavior is difficult in rivers. In stream tanks, we studied the effect of velocity on dispersal and holding ability, estimated swimming height, and used the data to estimate drift distance of pallid sturgeon. Dispersal was by days 0–10 embryos until fish developed into larvae on day 11 after 200 CTU (daily cumulative temperature units). Embryos in tanks with a mean channel velocity of 30.1 cm s−1 and a side eddy could not hold position in the eddy, so current controlled dispersal. Late embryos (days 6–10 fish) dispersed more passes per hour than early embryos (days 0–5 fish) and held position in side eddies when channel velocities were 17.3 cm s−1 or 21.1 cm s−1. Day and night swim‐up and drift by embryos is an effective adaptation to disperse fish in channel flow and return fish from side eddies to the channel. Early embryos swam <0.50 cm above the bottom and late embryos swam higher (mean, 90 cm). A passive drift model using a near bottom velocity of 32 cm s−1 predicted that embryos dispersing for 11 days in channel flow would travel 304 km. Embryos spawned at Fort Peck Dam, Missouri River, must stop dispersal in <330 km or enter Lake Sakakawea, where survival is likely poor. The model suggests there may be a mismatch between embryo dispersal distance and location of suitable rearing habitat. This situation may be common for pallid sturgeon in dammed rivers.

Age‐0 Sturgeon Accessibility to Constructed and Modified Chutes in the Lower Missouri River

“…82 position after settling and then swim upstream in order to enter a chute. Laboratory studies indicated that recently settled age-0 sturgeon (Kynard et al 2007), as well as individuals up to 75 mm total length (D. Deslauriers, South Dakota State University, unpublished data), may have difficulty holding position in water velocities that are relatively slow within the LMOR (e.g., 0.3 m/s). Furthermore, even if exogenously feeding sturgeon can hold position, these fish may experience a velocity barrier preventing them from swimming upstream into the chute as currents can be turbulent and swift at downstream chute outlets, particularly during higher water levels that are common during the free-embryo drift period.…”

Patterns and processes in the drift of early developmental stages of fish in rivers: a review

“…Apparently, the larvae of long migratory, potamodromous sturgeon species feature a continuous drift over several days and hundreds of kilometres (see Online Resource). Drift distance and duration are highly variable among species, and may be genetically coded in order to reach distinct nursery habitats and to compensate for the long upstream migrations of the adults (D'Amours et al 2001;Kynard and Horgan 2002;Kynard et al 2007aKynard et al , 2007bBraaten et al 2008Braaten et al , 2012. Instead of a continuous downstream movement, the early dispersal of other potamodromous species potentially includes a sequence of drifting phases (primarily during night), interspersed with periods of inshore settlement in nursery habitats (primarily during day) (Carter et al 1986;Gadomski and Barfoot 1998).…”

“…Flume experiments have a great potential to reveal specific peculiarities of the drift mode, however, they are rarely applied (Persat and Olivier 1995;Kynard et al 2007a;Kaminskas 2011;Pavlov et al 2011;Zens 2015). We suggest that future work should focus on the transport mode of different species (e.g.…”

“…Lateral positioning of drifting larvae, however, is thought to be a result of specific dispersal strategies; e.g., drifting near-shore to enhance the probability of being able to move into suitable habitat when coming close to it (Araujo-Lima and Oliveira 1998), or drifting offshore to accelerate transport and thereby minimize mortality . The distance covered during active drifting will clearly vary depending if larvae choose to drift at low (Lechner et al 2014b), intermediate (Schludermann et al 2012) or high currents (Oesmann 2003) and whether they drift low or high in the water column (Kynard et al 2007a).…”

“…Mathematical models have been used to estimate drift distances of some sturgeon species by integrating flow velocity and empirical data on drift duration, drift mode and swimming height (Kynard et al 2007a;Braaten et al 2008Braaten et al , 2012, but these sorts of studies are rare. There is an urgent need for research regarding the drift distance of other fishes (Fig.…”