Quote Originally Posted by Moveon View Post
How does a current in the lake make fish eggs float? The density of the eggs is what makes them sink or float. It's all about buoyancy.

Not only that but most lakes have small wind-driven currents in them. And if what you say is true then lakes without rivers running through them to give them a current would be devoid of Asian Carp. If you remember right they imported these Asian carp and raised them in ponds down south. They escaped the farm ponds when there was a big flood and have been making their way up the Mississippi River System ever since. And Eggs that float up to the surface are exposed to more sunlight and UV Light at the surface than they would if they were to sink to the bottom, even in shallow waters.

Where do you come up with this stuff? Do you have any sources?

https://www.asiancarp.us/News/fluegg.html

"To combat the threat of invasive Asian carp in the Great Lakes, the University of Illinois, in collaboration with the U.S. Geological Survey, has developed a tributary assessment tool to help predict which Great Lakes tributaries might be vulnerable to Asian carp spawning and could support egg transport and development. The tool, Fluvial Drift Simulator (FluEgg), is a three-dimensional numerical model developed to evaluate how rivers carry and spread Asian carp eggs. The model incorporates information about Asian carp egg development and river flows to provide insights regarding the likelihood of a river to be suitable for spawning, the potential of a river to transport Asian carp eggs in suspension until hatching, and the identification of the location of Asian carp eggs at different developmental stages. This information is important because it is believed Asian carp eggs must stay off the river bottom in order to hatch."



https://www.usgs.gov/news/asian-carp...iously-thought


"Laboratory experiments in flowing water using synthetic surrogate Silver Carp eggs demonstrate egg suspension at lower velocities than previously thought, according to a new U.S. Geological Survey study. The drift of synthetic eggs at a range of flows was evaluated to provide insight into both suspension of water-hardened Silver Carp eggs and the potential interaction of eggs with the bottom of a river.

Since Asian carp eggs must stay suspended in rivers to survive to hatching, it is important to understand what flows cause them to settle to the bottom. These critical flow conditions help scientists to determine which rivers may be suitable for Asian carp reproduction. Results are published in the journal PLOSONE."

"Scientists with University of Illinois and the USGS recently studied the suspension, transport and settling of Silver Carp eggs using synthetic surrogates at the Ven Te Chow Hydrosystems Laboratory, University of Illinois at Urbana-Champaign. The researchers found that 65 percent of the eggs were in suspension at mean velocities as low as 0.07 meters per second, considerably lower than previously thought (0.15 to 0.9 meters per second). If eggs are staying in suspension at these small velocities, then survival rates would be higher than previously expected in low flow systems. In addition, dimensionless ratios between turbulence and egg sinking rate were calculated for different flow conditions. These ratios can be used for first order assessment of egg suspension together with observed egg suspension mode from laboratory experiments. Results provide more information on egg suspension (i.e., 50 percent of eggs in suspension) than a mean velocity threshold.
Tatiana Garcia, USGS research hydrologist and lead author of the paper, performed experiments in moving water in a temperature-controlled re-circulatory flume with a sediment bed. Styrene beads were used as synthetic surrogate eggs to mimic the physical properties of water-hardened Silver Carp eggs. Egg suspension and drifting behavior of synthetic eggs was evaluated under different flow conditions and bed configurations."