What question did this study set out to answer?

This research aims to model the drift and survival of silver carp eggs and larvae in the Upper Mississippi River under various hypothetical spawning scenarios.

May 8, 2026Open Access

Drift and dispersion of silver carp (Hypophthalmichthys molitrix) eggs and larvae for hypothetical spawning scenarios in the Upper Mississippi River

Key Points

This research aims to model the drift and survival of silver carp eggs and larvae in the Upper Mississippi River under various hypothetical spawning scenarios.
Utilized Fluvial Egg Drift Simulator for modeling 450 spawning scenarios.
Examined conditions across 5 water temperatures and 9 flow variations.
Focused on two developmental stages: hatching and gas bladder inflation.
Eggs spawned upstream in Lake Pepin likely settle before hatching, increasing mortality rates.
Surviving eggs reach gas bladder inflation except at lower temperatures and higher flows.
Larvae spawned downstream drift out of the study area before reaching gas bladder inflation under most conditions.

Abstract

Invasive carp pose ecological and economic risks to North American freshwater systems. This study uses the Fluvial Egg Drift Simulator to model the drift of invasive silver carp (Hypophthalmichthys molitrix) eggs and larvae after hypothetical spawning in Pools 1–10 of the Upper Mississippi River. Although adult invasive carps have been detected in this region, no reproduction has been confirmed as of this publication. A total of 450 spawning scenarios were simulated, representing 5 water temperatures, 9 flows, and 10 spawning locations in the tailwaters of lock and dam structures. The study examined egg and larval positions at two key developmental stages: hatching and gas bladder inflation, when larvae seek nursery habitat. Under a wide variety of flow conditions and water temperatures, eggs spawned upstream from Lake Pepin (Pool 4) are likely to settle in the lake before hatching, possibly increasing mortality rates. Eggs that survive passage through Lake Pepin reach gas bladder inflation within the study area, except in scenarios with lower temperatures and higher flows. Conversely, larvae spawned downstream from Lake Pepin generally drift out of the study area before reaching gas bladder inflation, except in cases of higher temperatures and lower flows. These findings inform ichthyoplankton sampling strategies and management actions aimed at reducing invasive carp populations in areas likely to support recruitment.

Bookmark

View Full Paper