Yangtze Carp Study
View a slideshow to see how the sonic telemetry system works.
It may seem odd that a scientist from the Mississippi River, where Asian carp are wreaking havoc on the ecosystem, traveled half a world away to help save these same species in another river. But to Brian Ickes, it is a historic opportunity.
Ickes is a research ecologist with the U.S. Army Corps of Engineers’ Environmental Management Program and Long Term Resource Monitoring Program (LTRMP) at the U.S. Geological Survey’s Upper Midwest Environmental Sciences Center in La Crosse, Wisconsin. In March, he joined The Nature Conservancy as a Great Rivers Partnership (GRP) Fellow.
For the past three years, Ickes and Dr. Yao Yin, a fellow USGS colleague, have been working with the GRP to help scientists in China develop the methods and protocols needed to monitor and assess fish communities in the Yangtze River basin. There is little rigorous, scientific, baseline data on the status of the basin’s more than 340 fish species, and many species’ populations are starting to decline.
“Our colleagues in China have known for a long time that there are serious problems with fish populations in the Yangtze,” said Ickes, “but they haven’t had the tools they need to understand the nature of the problem.”
In May, Ickes spent 10 days on the Yangtze with students and scientists at the Yangtze River Fisheries Research Institute. The Institute provides science and technical support to fishery management, conservation and restoration activities in the Yangtze River basin.
Ickes was there to provide technical assistance to the GRP’s Yangtze partners who are initiating a new method to quantify fish populations. Data gathered will help determine the abundance and distribution of fishes in the Yangtze and can be compared to data collected by the LTRMP on similar species in the Mississippi River.
Tracking Carp to Save Them
Ickes was also in China to participate in a two-year sonic telemetry study, which is being funded by a $1.9-million grant from the Chinese government and supplementary funding from the GRP.
Which brings us to the Asian carp, specifically the silver, bighead, black and grass carp. Once very abundant in the middle and lower reaches of the Yangtze River, today the number of individuals and their distribution in the river basin are substantially reduced.
“These four species, historically, have been very important sources of protein throughout central China,” Ickes said, “and correspondingly, they hold a high position in Chinese culture and society.”
“But recent studies looking at fish eggs, larvae and fry noted a greater than 37,000-fold decline in their abundance in the Yangtze River between 1997 and 2005,” he added.
Ickes worked with Institute staff to initiate a sonic telemetry research project in the Yangtze that will fill critical data gaps in the life history of these four Asian carp species.
“Basically, you can think of sonic telemetry as analogous to a radio broadcast station, which transmits a signal to your home or car radio,” Ickes explained. “Except, in this case, the carp are the transmitters.”
Small transmitters were surgically imbedded into the abdomens of 58 carp, which were then released into the Yangtze. The fish are constantly broadcasting a signal that is picked up by 36 receivers spaced out along a portion of the river. The receivers record data on each carp’s movements (location, date, time, water depth and temperature), which can be retrieved wirelessly by driving the levee roads along the river.
“During the study, Institute scientists hope to learn volumes about what may be limiting successful reproduction and survival of these Asian carp species,” Ickes said, “and be in a better position to work with dam operators and other river managers to turn these declines around.”
Historic Moment for Fish Conservation
The fish monitoring work and telemetry study are helping Institute scientists develop the field resources and capabilities they will need to achieve their larger goal of implementing a basin scale environmental monitoring and assessment program in the Yangtze. The information generated will increase understanding of the biology of Asian carp and other species and help managers in both countries achieve management goals.
Building on the work in China, two Institute scientists will spend time with Ickes and his colleagues in Wisconsin this fall, where they will get intensive training in field operations, sampling design and protocols, GIS and database development, laboratory procedures and data analysis and reporting.
Ickes is excited by what the monitoring program and sonic receiver network mean for future fisheries research on both the Mississippi and Yangtze rivers.
“This receiver network, which the Great Rivers Partnership provided the funding to deploy, is an investment in the future of fisheries conservation and science in China,“ Ickes commented. “Now that it is in place, nearly any species can be studied, and we can compare data on similar species across great river systems. This is truly a historic moment.”