Adult Pallid Sturgeon Reproductive Ecology

Science Center Objects

CERC fish biologists study migrations, reproductive cues, and spawning behaviors of reproductive wild and hatchery-origin pallid sturgeon (HOPS) in the Missouri River Basin. 

USGS biological technician Ross Burlbaw prepares to release an upper basin reproductive pallid sturgeon

Student services contractor Ross Burlbaw prepares to release an upper basin reproductive pallid sturgeon following a physical assessment. 

(Public domain.)

The Issue: The pallid sturgeon is often recognized as one of the oldest North American fishes. Construction in the middle of the 20th century transformed the Missouri River into a contained, channelized, segment of dammed river and reservoirs from the flooding, meandering river it had once been. Scientists believe the reduced pallid sturgeon population of the late 20th century is a direct result of these changes to its natural habitat and newly-managed waterflows. Since its inclusion on the endangered species list in the 1990s, scientists have been closely monitoring and tracking the species to better understand migration and spawning behaviors. It is hoped that a better understanding of the natural behaviors will help identify the critical aspects of the modern river which impede natural reproduction and a self-sustaining population.

A larval sampling boat with nets prepared for deployment

A larval sampling boat with nets prepared for deployment

(Public domain.)

 

Addressing the Issue: Since part of the challenge to modern-day conservation is to find a way for all interested parties to enjoy the Missouri River simultaneously, scientists must first understand how the fish fits into the modern landscape. Scientists are using telemetered tracking, hydroacoustic mapping, and larval sampling to better understand pallid sturgeon behavior in modified (Missouri River), fragmented (passage at Intake Dam, migration to and up the Powder River, migration in the Yellowstone River upstream from Intake Dam), and mostly-natural (Yellowstone River) habitats. As hatchery origin pallid sturgeon (HOPS) are introduced into the population, scientists work to understand their ability to contribute to a breeding population through comparative studies of wild and HOPS reproductive behaviors.

 

Next Steps/Future Steps/Results: Scientists will continue and expand landscape-scale tracking of reproductive migrations and behaviors, responses to potential cues, through passive telemetry, boat-based (manual) tracking, and new PIT antennas. Scientists hope to implement and test high resolution 2D/3D telemetry systems to increase resolution on areal extent of pallid sturgeon aggregations and spawning events. The spawning events will be further refined through spawning event tags to identify exact oviposition locations. Passive receiver network use will be expanded, and detection probability models will be developed to ensure proper coverage and redundancy.

 

Return to Sturgeon Ecology

Return to Fish Reproduction and Development

Return to Comprehensive Sturgeon Research Project (CSRP)

Return to River Studies