Newswise — Getting lowered in by helicopter to the bottom of the Grand Canyon, New Mexico State University graduate student Meredith Campbell was surrounded by reddish canyon walls and contrasting blue water below.
That blue water is home to an endangered fish, the humpback chub, which was the purpose of her 11-day stay in the depths of the Grand Canyon in September.
This was definitely not like any of the fieldwork Campbell previously performed.
“Living in the Grand Canyon for 11 days was wonderful,” Campbell said. “I would go back in a heartbeat. It was probably one of the best experiences I’ve ever had.”
Accompanied by Colleen Caldwell, Fisheries Biologist for the U.S. Geological Survey and Affiliate Professor at NMSU’s Department of Fish, Wildlife and Conservation Ecology, Campbell’s mission was to collect swab samples to determine whether the Asian tapeworm is present in the humpback chub in the Colorado River watershed.
“The Asian tapeworm is a parasite that’s invasive, and it has started infecting many fishes in North America,” Campbell said. “The main goal of the research is to develop and look at the sensitivity and specificity of a non-lethal tool for detecting the Asian tapeworm.”
A non-lethal tool to detect infections is ideal because, at this time, necropsy is used. Necropsy is a method that involves terminating the fish and cutting it open in an attempt to visualize the tapeworm in the fish gut. Campbell, who is pursuing a master’s degree in wildlife science with an emphasis in fisheries sciences, said that necropsy is not an ideal method for an endangered species.
“There’s a genetic primer that’s been developed to detect the infection, and we’re looking at whether that will be an effective tool when paired with an anogenital swab,” she said. “We’re swabbing for fecal material, hoping to pick up whether there’s an infection. If the fish does have tapeworms, it’s going to be shed through the feces, as that’s how tapeworm infections are transmitted.”
Caldwell, who has a doctorate in ecology, explained the importance of such research.
“Meredith’s research is very important in context of helping us understand how we can prevent the extinction of an endangered fish,” Caldwell said. “It’s uncertain as to the level of parasitism this fish is experiencing in the wild, because the parasite we’re concerned about is not native to North America, and these fish didn’t evolve with this parasite.”
The Asian tapeworm has become a significant problem in United States hatcheries.
“Hatchery managers do treat fish when they bring them into captivity from the wild,” Campbell said. “They have reserve captive stocks of these fish that they keep, and when they bring wild fish in, they are treating them with a drug that is basically the same type used to de-worm dogs.”
Along with other U.S. Fish & Wildlife Service employees, Campbell and Caldwell spent Sept. 20 through Oct. 2 in the Grand Canyon swabbing many fish for fecal samples.
Following her sample collecting, Campbell hit the research lab at the Southwestern Native Aquatic Resources & Recovery Center in Dexter, New Mexico. SNARRC is part of the United States Fish & Wildlife Service, and it contains the Southwestern Fish Health Unit, which monitors aquatic species’ health issues for the southwest region.
The majority of the funding for Campbell’s research is provided by SNARRC.
“I’m a volunteer on the U.S. Fish & Wildlife Service crew, and in return, I get to take my swab samples from the humpback chub back to the lab in Dexter to do DNA extractions and PCRs to see if I can pick up any of those infections in the wild fish,” Campbell explained.
Through her research, she hopes to determine the percentage of the population that is infected.
“The U.S. Fish & Wildlife Service is interested in being able to use this non-lethal method reliably on the captive populations of the humpback chub that they currently have,” Campbell said. “Using this method with the wild fish is an opportunity to look at ecological consequences of infection, to get acquainted with the species in the wild and to get a better sample size in terms of prevalence.”
Thus far, many of the Asian tapeworm studies among wild fish have been limited to small sample sizes. However, Campbell was able to swab hundreds of fish, because the process is not shown to be harmful.
“It’s very important that Meredith is able to identify – using a molecular technique – whether or not this parasite is prevalent throughout the wild fish population of the humpback chub,” Caldwell said.
After months of analysis, Campbell will be able to provide information to the U.S. Fish & Wildlife Service regarding the prevalence and percentage of the parasite among the fish.
“The type of research Meredith is doing is bringing some important notoriety to the university,” Caldwell said. “The U.S. Fish & Wildlife Service doesn’t often provide the opportunity to ask these kinds of questions to everybody. For the U.S. Fish & Wildlife Service to trust New Mexico State University in developing a technique for such an important and fragile – on the landscape – species says a great deal.
“We’ve earned the trust and respect of an agency. And I’m hoping, because of the work we’re doing, they will come back again to ask for more help. In return, we are given the opportunity to train future scientists such as Meredith.”
“Eye on Research” is provided by New Mexico State University. This week’s feature was written by Kristie Garcia of University Communications.
RSS