1. FISHERIES POSTER SESSION
ASIAN CARP SYMPOSIUM
Simulation of the Fate and Transport of Asian Carp Eggs in the Lower Saint Joseph River: A Great Lakes Tributary
As the eggs advect downstream, the mass of eggs disperses in the streamwise direction due to shear dispersion. Shortly after the spawning event, and within the entire study reach, the eggs are distributed throughout the water column.
II. Application to the Saint Joseph River
The transport of silver carp eggs in the lower 40.1 km of the St. Joseph River was simulated using FluEgg. Two data sources were used. First, observed hydraulic data, and second, simulated hydraulic data from a HEC-RAS model.
FluEgg simulations using observed data
The average discharge, water depth, streamwise velocity, and shear velocity of the simulated reach are m3/s, 2.1m, 0.7 m/s, and 0.06 m/s, respectively.
Figure 4. Temporal and spatial evolution of the simulated egg mass in the Lower Saint Joseph River using longitudinal ADCP measurements (Murphy and Jackson, 2013).
The snapshot of eggs drifting in the vertical-longitudinal space (Fig. 4A) illustrates the evolution of the egg plume. The temporal and spatial evolution of the egg mass (Fig. 4B, 4C and 4D) is useful in egg sampling planning and the development of control strategies in streams with well established populations. For example, it helps to determine the downstream distance from a known spawning location to measure and collect egg samples. The egg travel time to a specific downstream distance is explored in Fig. 5A, Fig. 5B illustrates the vertical position of the eggs at a given downstream distance from the spawning location.
Figure 5. Travel time distribution 36.8 km downstream from Berrien Springs Dam (A). Distribution of eggs over the water column at 36.8 km downstream from Berrien Springs Dam (B).
Figure 6. Longitudinal distribution of the eggs at hatching time. Eggs at risk of hatching (ERH) is calculated as the total percentage of eggs in suspension.
The longitudinal distribution of the eggs and the risk of hatching at a given post-spawning time can be visualized in Fig. 6. The cumulative sum of the percentage of eggs in suspension at hatching time is a proxy for hatching risk.
Tatiana Garcia1, Elizabeth A. Murphy2, P. Ryan Jackson2, and Marcelo H. Garcia1
1 Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, IL, USA.
1 U.S. Geological Survey, Illinois Water Science Center, Urbana, IL, USA.
Abstract
If Asian carp migrate to the Great Lakes, they will require tributaries with fast moving water to spawn and to support egg development. The identification of tributaries suitable for spawning and egg development has previously been accomplished by comparing the hydrodynamic and environmental characteristics of the river with the characteristics of rivers where Asian carp have successfully recruit. We used the FluEgg (Fluvial Egg Drift Simulator) model to predict transport and dispersion of Asian carp eggs in the Lower Saint Joseph River, a tributary of Lake Michigan. The input data for FluEgg was generated in two ways; first using field observations during a high flow event and second using HEC-RAS model data. The HEC-RAS model hydrodynamic input data were used to simulate different scenarios covering a broad range of flows and water temperatures. FluEgg simulations predict the highest percentage of eggs at risk of hatching occurs at the lowest discharge and at peak summer water temperatures. Results illustrate the dynamic component associated with egg transport and dispersion, as well as egg-hatching risk due to the relation between river length, hydrodynamic characteristics, and water temperatures. Results indicated sufficient drifting distances to enable hatching depend strongly on the river hydrodynamics and on the water temperature of the river.
I. FluEgg Overview
The FluEgg model (Garcia et al., 2013 and Garcia et al., 2015) can be used as a tool to study the transport and dispersal patterns of Asian carp eggs in tributaries, or to simulate the transport of Asian carp eggs in other water bodies, including those with established Asian carp populations. A user-friendly graphical user interface (GUI) and a free executable version of the model make the user’s interaction with the model simple, fast, and efficient. The user interface includes a set of post-processing tools that allows the user to visualize and perform analysis on the output of FluEgg simulations. In FluEgg, the river is discretized into a series of cells and the eggs are simulated as discrete particles. The model predicts the advective, deterministic component and the diffusive, stochastic component of individual eggs movements in the streamwise (x), transverse (y) and vertical direction (z) at every time step.
Egg development
FluEgg uses the time-dependent relations of the density of the eggs at a reference temperature equal to 22 °C. These time-dependent relations were found by fitting experimental data by Chapman and George (2011a and 2011b) on cultured silver and bighead carp and then correcting to the reference temperature. A generic function relating the density of the eggs as a function of ambient temperature is used to account for changes in the density of the eggs with respect to ambient water temperature.
Egg Hatching time
The approximate hatching time is calculated based on the temperature averaged over all the cells. FluEgg uses an empirical function derived from the data compilation completed by Murphy and Jackson (2013) on hatching times as a function of temperature. For a given species the hatching time is calculated based on the temperature averaged over all the cells.
Figure 2. FluEgg main graphical user interface
Figure 3. Conceptual schematic of FluEgg.
FluEgg simulations using simulated hydraulic data
Using simulated hydraulic data for a range of flow events at different water temperatures into FluEgg input provides a more holistic analysis of egg dispersion and egg-hatching risk. FluEgg simulations illustrated that the most critical condition occurred at the lowest tested discharge and at peak water temperatures. In summary, simulation results showed Asian carp eggs can hatch successfully (eggs at risk of hatching greater than 27 percent) in the Lower Saint Joseph River under a broad range of hydrodynamic conditions for temperatures greater than 23°C in a river reach that is about 40 km long.
Figure 1. Map of the Lower Saint Joseph River in Michigan.
Figure 2. Travel time distribution 36.8 km downstream from Berrien Springs Dam (A). Distribution of eggs over the water column at 36.8 km downstream from Berrien Springs Dam (B).
References
Chapman, D. C., George, A. E., 2011a. Developmental rate and behavior of early life stages of bighead carp and silver carp. U.S. Geological Survey Scientific Investigations Report
Chapman, D. C., George, A. E., 2011b. Specific gravity of silver and bighead carp eggs. Unpublished raw data, U.S. Geological Survey.
Garcia, T., Jackson, P. R., Murphy, E. A., Valocchi, A. J., Garcia, M. H., Development of a Fluvial Egg Drift Simulator to evaluate the transport and dispersion of Asian carp eggs in rivers. Ecological Modelling 263, 211–222.
Garcia, T., Murphy, E. A., Jackson, P. R., Garcia, M. H., in press. Application of the FluEgg model to predict transport of Asian carp eggs in the Saint Joseph River (Great Lakes tributary). Journal of Great Lakes Research.
Murphy, E. A., Jackson, P. R., Hydraulic and water-quality data collection for the investigation of Great Lakes Tributaries for Asian carp spawning and egg-transport suitability. U.S. Geological Survey Scientific Investigations Report
Figure 7. Box-plot of the longitudinal location of the eggs at hatching time at different discharge, as a function of water temperature (A) based on 52 FluEgg-simulations of the Lower Saint Joseph River. Eggs at risk of hatching (ERH) at different discharges as a function of water temperature (B). Hatching time (TH) as a function of water temperature (C).