Early Life History of Bighead, Silver, Black, and Grass Carps
Grass, bighead, black, and silver carps spawn in turbulent rivers, their eggs develop and hatch while drifting downriver. The larvae have a short period of development in the drift, and then they must swim from the mainstem of the river and find appropriate low- or no-flow nursery areas. Rivers which are not long enough, turbulent enough, or without nursery areas in the correct locations are not likely to support survival of these fishes. If we can cause these problematic fishes to spawn in locations that will not support survival, or if we can locate spawning and nursery areas to harvest fish or prevent their survival, these would be useful control methods.
CERC scientists are studying the temperature-based development of eggs and larvae of these four invasive carp species as well as the behavior of larvae and eggs of these fishes in a flume. This will generate data to enhance drift models for early life history stages. These models aid in assessing the suitability of a river for spawning, the survival of young, the locations where captured eggs and larvae were spawned. As well as determining the portion of the river where the larvae are most likely to attempt to laterally disperse from the spawning river into nursery habitats and therefore where larvae might be susceptible to control methods.
The Issue: The early life stages (eggs, larvae, and juveniles) represent a critical period in the lives of fish, one characterized by high mortality rates. Survival of these stages commonly determines year-class strength and overall population size. These life stages are not captured using standard fishing gear meant for adults, thus there is a lack of knowledge about survival rates, habitat requirements, recruitment and dispersal potentials. Understanding the factors during early development is needed for risk analysis of establishment, prediction of transport distances and available nursery habitats, as well as, determination of spawning location, and development of controls which reduce early life stage survival and year-class strength.
Addressing the Issue: By combining early life biological data with physical and hydraulic data, models such as FluEgg have been developed to predict transport within a specific river system. CERC scientists have learned:
- Temperature-dependent developmental rates of grass carp, bighead carp, and silver carp eggs and larvae.
- Survival rates of grass carp eggs that settle to the bottom.
- Physical characteristics of grass carp, bighead carp, and silver carp eggs useful for identification and transport potential.
- Swimming behaviors and capabilities of grass carp, bighead carp, and silver carp larvae.
- Neurosensory development in grass carp larvae to determine potential environmental cues for dispersal.
- Physiological tolerances of larval invasive carp, such as salinity and hypoxia.
- Effects of turbulence on the survival of grass carp eggs and larvae.
In addition, CERC scientists are currently working on projects to:
- Determine early life history characteristics of black carp, including developmental rates, stages, physical characteristics of eggs, and swimming behavior.
- Assist with the development of control mechanisms aimed at early life stages, such as the Oblique Bubble Screen.
- Train and assist other agencies in the identification of captured larvae.
Return to Invasive Species Ecology
Return to Fisheries and Invasive Species
Grass, bighead, black, and silver carps spawn in turbulent rivers, their eggs develop and hatch while drifting downriver. The larvae have a short period of development in the drift, and then they must swim from the mainstem of the river and find appropriate low- or no-flow nursery areas. Rivers which are not long enough, turbulent enough, or without nursery areas in the correct locations are not likely to support survival of these fishes. If we can cause these problematic fishes to spawn in locations that will not support survival, or if we can locate spawning and nursery areas to harvest fish or prevent their survival, these would be useful control methods.
CERC scientists are studying the temperature-based development of eggs and larvae of these four invasive carp species as well as the behavior of larvae and eggs of these fishes in a flume. This will generate data to enhance drift models for early life history stages. These models aid in assessing the suitability of a river for spawning, the survival of young, the locations where captured eggs and larvae were spawned. As well as determining the portion of the river where the larvae are most likely to attempt to laterally disperse from the spawning river into nursery habitats and therefore where larvae might be susceptible to control methods.
The Issue: The early life stages (eggs, larvae, and juveniles) represent a critical period in the lives of fish, one characterized by high mortality rates. Survival of these stages commonly determines year-class strength and overall population size. These life stages are not captured using standard fishing gear meant for adults, thus there is a lack of knowledge about survival rates, habitat requirements, recruitment and dispersal potentials. Understanding the factors during early development is needed for risk analysis of establishment, prediction of transport distances and available nursery habitats, as well as, determination of spawning location, and development of controls which reduce early life stage survival and year-class strength.
Addressing the Issue: By combining early life biological data with physical and hydraulic data, models such as FluEgg have been developed to predict transport within a specific river system. CERC scientists have learned:
- Temperature-dependent developmental rates of grass carp, bighead carp, and silver carp eggs and larvae.
- Survival rates of grass carp eggs that settle to the bottom.
- Physical characteristics of grass carp, bighead carp, and silver carp eggs useful for identification and transport potential.
- Swimming behaviors and capabilities of grass carp, bighead carp, and silver carp larvae.
- Neurosensory development in grass carp larvae to determine potential environmental cues for dispersal.
- Physiological tolerances of larval invasive carp, such as salinity and hypoxia.
- Effects of turbulence on the survival of grass carp eggs and larvae.
In addition, CERC scientists are currently working on projects to:
- Determine early life history characteristics of black carp, including developmental rates, stages, physical characteristics of eggs, and swimming behavior.
- Assist with the development of control mechanisms aimed at early life stages, such as the Oblique Bubble Screen.
- Train and assist other agencies in the identification of captured larvae.
Return to Invasive Species Ecology
Return to Fisheries and Invasive Species