Ecological requirements for pallid sturgeon reproduction and recruitment in the Missouri River—Annual report 2013

Abstract

Diagram showing the Sturgeon Information Management System that accommodates and integrates multiple disparate data types by using a suite of software to accommodate various data formats and the demand for near real-time updates .

Reproductive strategy, spawning induction, spawning temperatures and early life history of captive sicklefin chub Macrhybopsis meeki

“…hyostoma: Minckley, 1959;Cross, 1967;Reeves, 2006). The second temperature treatment was based on the daily temperature fluctuations observed during the ascending annual temperature cycle in the Missouri River; eight sites below rkm 565 with 7-11 years of annual temperature data (Delonay et al, , 2012(Delonay et al, , 2016a. The highest temperature in this treatment was 23 ∘ C from 1600 to 2200 hours and the lowest temperature was 20 ∘ C from 0400 to 1000 hours; in between these two periods the temperatures changed 1 ∘ C every 3 h. In all treatments, temperature was recorded every 30 min and differed from target temperatures by 0·20 ± 0·06 ∘ C (n = 73).…”

Reproductive ecology and movement of pallid sturgeon in the upper Missouri River, Montana

“…Pallid sturgeon spawning has not been documented in RPMA1 (i.e., the reach for this study), and the timing of spawning relative to peak discharge is unknown. The observation of downstream spawning migrations differ from what has been suggested to occur in the lower Missouri River (DeLonay et al, ) and in the upper Missouri River downstream of Fort Peck Reservoir including the lower Yellowstone River (DeLonay et al, ; Fuller et al, ). Anadromous sturgeon spp.…”

“…Additional weeks of tracking during the ascending limb would have allowed more certainty in the conclusion that pallid sturgeon move downstream to spawn, but anecdotal evidence and the upstream locations of reproductive fish during the recapture effort corroborates this conclusion. Pallid sturgeon spawning movements are hypothesized to be cued and occur on the ascending limb of the hydrograph with spawning taking place on the descending limb of the hydrograph (Fuller et al, ), which has been documented in the Yellowstone River (DeLonay et al, ; Fuller et al, ). Pallid sturgeon spawning has not been documented in RPMA1 (i.e., the reach for this study), and the timing of spawning relative to peak discharge is unknown.…”

“…In the lower Missouri River, hatchery‐origin female pallid sturgeon were reported to have spawned, providing evidence that the hatchery‐origin fish are capable of spawning in the wild (DeLonay et al, ). Spawning events have been well documented for wild fish in RPMA2 (the Yellowstone and Missouri rivers below Fort Peck; DeLonay et al, ; Fuller, Jaeger, & Webb, ) but have not been confirmed in RPMA1. Thus, there is a need to resample reproductively‐active female pallid sturgeon (i.e., hatchery‐origin and wild) following the putative spawning season to determine ovulatory success in RPMA1.…”

“…Thus, there is a need to resample reproductively‐active female pallid sturgeon (i.e., hatchery‐origin and wild) following the putative spawning season to determine ovulatory success in RPMA1. Furthermore, the presence of male aggregations have been used by researchers to identify spawning sites weeks prior to spawning activity in the Yellowstone River (DeLonay et al, ) but have not previously been described for pallid sturgeon in RPMA1.…”