Searching for Jellyfish
Jellyfish, squishy, sometimes venomous, bags of goo are found throughout the world in both marine and freshwater ecosystems. They are neither fish, nor, technically, jelly, but evolutionarily basal animals with two tissue layers, radial symmetry, and a host of weird and wonderful adaptations to life underwater. Though they are found in lakes and oceans around the world, jellyfish are not the easiest animals to collect. Nets and trawls can tear their soft bodies apart, making many ecologic studies impossible. ROVs, which offer the ability to perform visual observations and collect jellyfish with more gentle sampling devices can help overcome this challenge.
This initiative will provide OpenROV Tridents to researchers, students, citizen scientists, and explorers who want to learn more about jellyfish (and related groups like as ctenophores).
Discover one of our Expeditions
The last thing I expected when I visited Thoreau’s famous Walden Pond was to find jellyfish. But small, nickel-sized jellies were teaming in the cold October water, underneath a canopy of red and gold leaves. As a scientist who studies jellyfish, I desperately wanted to learn more about these odd freshwater jellies, so I returned to the pond with my high-tech equipment: a net, collecting jars, and a bright green pool noodle. I floated around, freezing, on the noodle for nearly an hour before I found the jellies. These small, clear jellies weren’t spread evenly over the pond like I’d thought; instead, they were all clumped in a single bay at the surface, not far from the stone remnants of Thoreau’s cabin. Though I collected a number of jellies, they did not breed successfully in captivity, and within a few weeks all the jellies in Walden Pond were gone. My chance to study the freshwater jellies that year had passed. Though freshwater jellies seem elusive, they are all over the United States, often appearing and disappearing with little notice. Even though they’ve been reported in 44 of the 48 contiguous united states, we know very little about these animals. For example, all the animals I observed were grouped together in a small area of the lake. Do they passively concentrate in certain parts of a lake, or like the famous golden lagoon jellies on Palau, do they actively migrate throughout the day? If we can locate freshwater jellies effectively, and in multiple different lakes, we’ll have a much better chance of answering these questions. However, floating on a pool noodle in cold water simply is not an effective strategy for finding and studying freshwater jellies. I propose to study freshwater jellyfish, in collaboration with citizen scientists, using a Trident ROV. We will use the ROV to locate jellies in multiple lakes, and examine their distribution and daily movement patterns. Once we find jellies, I will collect them for further study in the lab. I will conduct this work in conjunction with an outreach campaign with the local community. I will alert citizens to the general presence of freshwater jellyfish through op-eds in local newspapers, flyers, and public talks. Citizens will report sightings to me via email or through our expedition webpage, and I will invite them to join me in the field as we locate freshwater jellies with the Trident ROV. With the aid of a Trident ROV and citizen science, we will be able to study these strange and beautiful animals, and hopefully catalyze interest in freshwater jellies and local freshwater ecology throughout the region. (photos: Number 1: The old "old way" of collecting jellies in a pond with a pool noodle Number 2: A freshwater jellyfish, from Wikimedia commons)