Oceans and coastal ecosystems support an incredible diversity of fish and invertebrates that have sustained human societies for millennia through fisheries and aquaculture. These species are key players driving ecosystem structure and function, but human activities threaten the productivity and diversity of marine life. In the Anthropocene, finding a balance between harvest and conservation of fish and invertebrates, and mitigating other human impacts on marine ecosystems, will be key to sustaining productive, resilient, and biodiverse coastal and marine ecosystems. We address broad problems of population and community ecology using long-term quantitative sampling, animal behavior/movement studies, and innovative experiments at multiple spatial and temporal scales. Our studies analyze human impacts and natural change in freshwater, estuarine and marine systems.
Understanding Sharks One Tag at a Time
Posted by KristenM on June 14th, 2018
by Mollie McNeel
Sharks. They’re everyone’s favorite underwater enemy. Between nerve-wracking dramas like Jaws to stories about prehistoric mega-sharks, we have all but made the shark species a completely fictionalized being. But scientists at the Smithsonian Environmental Research Center (SERC) are hoping to change that.
Charles “Chuck” Bangley, a marine ecologist at SERC, travels up and down the East Coast catching and tagging four species of sharks found in the Chesapeake Bay and along the Atlantic: smooth dogfish sharks (Mustelus canis), bull sharks (Carcharhinus leucas), blacktip sharks (Carcharhinus limbatus) and dusky sharks (Carcharhinus obscurus).
The team of researchers is looking to understand more about these sharks’ movements and what areas of habitat are favorable to each species, explains Bangley. But it has another major focus: public outreach.
Sharks are often seen as fearsome predators who strike without warning, making many people believe that all sharks are dangerous to humans. But these scientists are working to swap the Jaws-inspired fear with fascination.
“People are always interested to know where sharks are and whether or not they’re near their beach house or in the areas where they used to swim as a kid,” says Bangley. “There’s still that fear, but it’s being replaced with curiosity.”
To help foster this curiosity, Bangley heads out on the water in search of the four species he’s tagging. Once the team catches a shark, the scientists flip it onto its back, putting it into a nonresponsive state, numb the area with lidocaine and make a small incision where they insert a small, black, cylindrical tracker. After implanting and activating the tracker, Bangley stitches the shark up and releases it back into the water—all in under five minutes.
“We tag these sharks and we want to see where they go and what types of waters they are drawn to,” says Bangley. “We want to look at potential shark habitat and known shark habitats in relation to highly populated areas, closed-off areas, areas of high fishing activity or areas of offshore development.”
By creating maps out of the data they receive, scientists hope to help inform both policy makers and the public on which areas these sharks are inhabiting and why it’s in our best interest to keep them there.
This kind of info would offer a huge leg up for conservation efforts. Policymakers are often unable to conserve threatened sharks due to the lack of appropriate data on shark movements and behavior—data which tagging and tracking work can provide. These data can help determine whether marine protected areas are large enough or in the right locales to adequately protect sharks. They can also reveal “hot spots” for shark activity that policymakers can prioritize for protection.
“This knowledge helps limit the areas that end up being closed off to other uses of the ocean while still protecting the species,” says Bangley. “It ultimately advances our goal of harmonious living between humans and wildlife.”
Shark tagging can offer real benefits to humans in other areas as well, such as fishing and even tourism. The fishing industry is way ahead of scientists in understanding where the sharks and fish are, according to Bangley.
“With a lot of this data we are really just catching up to what the fishermen know now, because they’re out on the water much more often than us,” explains Bangley. But more concrete knowledge of shark migration patterns can help fishermen avoid getting their nets bitten by sharks’ razor-sharp teeth. Sharks are commonly captured accidentally as “by-catch” and chew through fishing nets, delaying fishing time and leading to a loss of overall catch.
Meanwhile, as almost every aquatic ecosystem is home to some shark species, divers and wildlife enthusiasts will pay good money to view sharks in their natural habitats.
Shark-based tourism provides economic benefits that can support sustainable tourism ventures, using income from the activity costs. Some governments even receive additional revenue through permit, entry or tag fees. By tagging sharks and therefore knowing where they are during various times of the season, it makes sightings more reliable and allows the industry to grow.
The scientists involved in this project believe that having multiple ways people can access information on sharks and the tagging process is the best way to reach them. Therefore, they often go out into the community giving presentations on shark and have information readily available online.
On SERC’s website and the Movement of Life Initiative page, viewers can find information on each species of shark being tagged, more information on the project as a whole and an interactive map following one very lively juvenile blacktip shark. There is a big emphasis on maps, explains Bangley, because everyone wants to see where the animals are and follow them as they’re moving around.
In the future, the scientists hope to make the online aspects more interactive and enable tracking in real time, with maps that allow visitors to scroll in, see exactly where a shark is, what species it is and how deep it was swimming.
“I think the more information the public has about these creatures, the more they will begin to realize there’s a lot more going on here than just their ability to bite,” says Bangley.
Learn more about shark research at the Smithsonian Environmental Research Center:
Understanding the ecology of fisheries is critical to maintaining resilient, productive and biodiverse coastal and marine ecosystems. Fishing is an important sector of coastal economies, provides an important supply of food for human societies, and is an activity of great cultural and historical importance. But fisheries have also contributed to the decline of coastal and marine ecosystems through changes in biomass and community structure, disruption of food webs, and alteration of habitats. Using the Chesapeake Bay as a model system, we are addressing fisheries issues including the impacts of harvest, restoration, and conservation on populations, communities and ecosystems, habitat use, migrations and connectivity with other coastal ecosystems. To learn more about our fisheries ecology and conservation research, please visit the following webpages:
Our long-term studies of fish and invertebrate communities in the Rhode River, Maryland study site offer a window in the community structure and population dynamics of fish and invertebrate communities in one of the most productive ecosystems on earth, the Chesapeake Bay. Spanning more than three decades, this research tracks seasonal, annual, and decadal variation in species composition and abundance of fishes and macro-invertebrates. Sampling methods include trawling, seining, a fish weir, benthic infauna cores, and tethering experiments. The long-term descriptive data, in combination with our experimental studies, provide an unusual database for exploring populations, communities, predator-prey relationships, impacts of fisheries, and impacts of environmental variability and climate change, and other ecological processes. To learn more about our long-term research, please follow the links below:
Many species on the planet migrate during their lifetime, using different habitats during specific life stages. What habitats are most important and why? How will climate change affect migrations? What are the benefits and costs of migration to individuals? How can we best manage fisheries for migratory species? How do migratory species affect community structure and ecological processes? To learn more about our Movement of Life Initiative research, please visit our Movement of Life Initiative webpage:
Welcome to the Educator Resources page-- below are a collection of lessons, web resources, and videos arranged by subject to help you quickly find resources in your interest area to create lesson plans or activities. Maryland follows the Next Generation Science Standards for K-12 science content standards. Access the Next Generation Science Standards broken down by topic at the National Science Teachers Association website.
Are you a teacher visiting SERC? Click here to learn more about how to prepare for your field trip to our campus and other general resources!
Discover, create, and share more resources and educational experiences on the Smithsonian Learning Lab!
Lesson: Movement of Life Initiative: Discover What Makes Sharks Move
Lesson: Sharks and Shorelines
Activity: Ecosystem Explorer | EARTH A New Wild
Reading/ Video: SERC’s Shorelines Blog "Following the Movement of Life: Tagging Sharks and Rays"
Reading/ Video: SERC’s Shorelines Blog "Tracking the Bay’s Cownose Rays"
For more information about shark migration, check out Smithsonian's Movement of Life Initiative!
Lesson: The Blue Crab's Chesapeake Journey
Video: SERC Scientists Video from the Smithsonian Science Education Center, “How do Scientists Track and Monitor blue Crab Populations in the Chesapeake Bay?
Video: SERC Ecosystems on the Edge video by one of our scientists, called “Blue Crabs: Top Predator in Peril”
Lesson: Juvenile Oyster Disease: A Growing Problem
Video: Determining the Resiliency of Juvenile Oysters in the Chesapeake Bay