Demographic Rate Variability of Bighead and Silver Carps Along an Invasion Gradient

Abstract

Invasive Bighead Carp Hypophthalmichthys nobilis and Silver Carp H. molitrix have infested and caused largescale ecological and economic damage to the Illinois, Mississippi, and Ohio rivers. We compiled demographic data from 42,995 fish from 23 pools in the Illinois, Mississippi, and Ohio rivers, which universities and management agencies previously collected as part of management, monitoring, and research activities. We used this data set to test whether demographic rates (length–weight relations including body condition, mortality, growth curves, and female maturity curves) varied among subpopulations across a gradient of invasion status. We found that length–weight relations and growth curves varied among subpopulations, whereas maturity curves did not. Our findings demonstrated spatial variability in demographic rates for Bighead and Silver carp across a broad geographic area in relation to invasion status and river conditions. Herein, we provide general subpopulation management options and present different hypotheses to explain the observed spatial variability in demographic rates.

Analysis of per capita contributions from a spatial model provides strategies for controlling spread of invasive carp

“…Thus, this analysis provides a baseline to which more complex models can be compared. For example, invasive carp exhibit demographic variability across their invasive range (Erickson et al, 2021; Lenaerts et al, 2021). Ongoing efforts are underway to combine population models (e.g., Tsehaye et al, 2013) with movement data (e.g., Coulter, Brey, et al, 2018) in a size‐dependent spatially explicit invasive carp (SEICarP) model (Asian Carp Regional Coordinating Committee, 2018; Cupp et al, 2021).…”

MetaIPM: Placing integral projection models into a metapopulation framework

“…These parameters may be estimated using tools such as the fishStan v2.0 package (Erickson et al, 2020). An example application of this package on a large dataset can be found in Erickson, Kallis, et al (2021a). When running the stochastic model, different draws from the posterior distribution are used for each simulation run.…”

“…This demonstrates how IPMs, and more specifically MetaIPM allows the direct modelling of populations where length‐based distributions are important. We used a posterior distribution of demographic data (previously estimated using fishStan v2.0 package [Erickson et al, 2020] on a large dataset [Erickson, Kallis, et al, 2021a]). Likewise, we used hydroacoustic data to scale the relative starting carp populations (Coulter et al, 2019).…”

fishStan: Hierarchical Bayesian models for fisheries

“…We created the original package for Erickson et al (2021b) that estimated bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix) demographic rates in the Illinois, Mississippi, and Ohio Rivers. This paper also includes a public, peer-reviewed dataset (Erickson et al, 2021a) and a public, peer-reviewed workflow (Erickson & Kallis, 2021).…”