A Review of Grass Carp and Related Species Literature on Diet, Behavior, Toxicology, and Physiology Focused on Informing Development of Controls for Invasive Grass Carp Populations in North America

Abstract

Grass carp (Ctenopharyngodon idella) are globally important in aquaculture and aquatic vegetation control. However, escaped grass carp have established invasive populations. A targeted keyword search was performed on a carp (order: Cypriniformes) literature database maintained by the U.S. Geological Survey to identify literature relevant to grass carp. Additional sources cited in reviewed documents and provided by numerous reviewers were also included. There were three focus areas designed to provide support for invasive grass carp management: (1) diet and behavior; (2) physiological constraints, toxicity, and biology; and (3) gut physiology. Each focus area provides information to guide development of potential pathways for invasive grass carp control. Information from other carp species was used to fill in gaps where grass carp information was lacking and provide additional, potential research directions. Diet-related information included food selection and aquacultural diet formulations. Behavioral information included stimuli and non-physical barriers to attract, repel, or stop movement. Physiological constraints, toxicology, reproductive control, and biological control provide a research review for control options. Gut physiology and related control pathways provide knowledge to improve toxin or pathogen delivery. This review provides a basis for developing approaches and research for controlling invasive grass carp populations, aquaculture, and native population management.

Sicklefin Chub (Macrhybopsis meeki) and Sturgeon Chub (M. gelida) Temporal and Spatial Patterns from Extant Population Monitoring and Habitat Data Spanning 23 Years

“…It is possible that this negative relationship is due to either the reduction in already reduced shallow spawning habitats or the loss of sicklefin chubs from the system by being swept into the Mississippi River by higher discharge in the more channelized LMR [1,33]. Relationships to river discharge have been shown for spawning in other cypriniform fishes such as grass carp (Ctenopharyngodon idella; [67] and references therein) and blue suckers (Cycleptus elongatus, [68]) and recruitment for other small, benthic fish species such as the Neosho madtom (Noturus placidus, [50]). Our results provide some additional factors that may result in niche partitioning between these two chub species, but determining this requires further investigation.…”

“…There is also the potential that adult pallid sturgeon, as chub predators, may have at least part of their demonstrated population declines [3,15] attributable to the loss of prey resources, e.g., chubs. The stocking of predatory fish, a common fisheries management tool, can cause declines in prey fish populations ( [67] and references therein). Again, these combined results support the hypothesis that improving conditions for sicklefin and sturgeon chub conservation and recovery would be expected to improve conditions for shovelnose sturgeon, pallid sturgeon, and channel catfish in the MR indirectly through increased habitat availability and associated food resources and directly for adult pallid sturgeon via increased prey resources.…”