Prepped with dissection tools, gloves, measuring tape, dry ice and cooler, biology graduate students Andrew Barrios and Homam Jamal headed to Catalina Island: Another rare oarfish washed ashore.
In June, before dawn, they took a research boat to the island to collect samples for their studies. The budding researchers dissected the giant, 206-pound, 15-foot female fish to collect its “pterygiophores,” or the bones that support the dorsal fin. They also brought back the fish’s 50-pound head and 7-foot-long, 25-pound reproductive organs.
“This was my first time doing a dissection on the beach and to do it on an oarfish was just an incredible experience that I am extremely thankful for,” said Barrios, who is studying the fish’s jelly-like bone structure, which he began as a CSUF undergraduate. “It was a long day, but having the opportunity to study such a large and rare fish is truly an honor.”
“I had never seen a fish that big,” said Jamal, who also studies the physiology of rockfish. “Oarfish are an amazing species. If I had one word to describe this opportunity it’d be ‘unique.’ “
That day was the first time the aspiring scientists had raced to recover remains of the silvery, red-finned oarfish for research sake, but not the last.
Since, faculty and student researchers have collected remains of two more oarfish in August and September. Two years ago, the entire remains of a 14-foot female, discovered on the shore in Oceanside, came to campus. A CT scan of its skeleton resulted in 75,000 images to reconstruct a 3D model for the bone study.
The oarfish lives in depths of about 600 feet. But in recent times, the sea creatures are making their way to the ocean’s surface, raising questions as to why they are dying.
By studying the fish remains, scientists can get closer to solving some of the mysteries about the giant bony fish of sea-serpent tales, in which scientists know little, said Misty Paig-Tran, assistant professor of biological science.
Paig-Tran and Barrios are researching the oarfish’s bone structure, as well as the mechanics of how the fish moves its mouth and feeds on krill and small crustacean.
“I’m interested in how different the material properties of the bones of the oarfish are compared to its relatives, like the opah and king-of-salmon,” said Barrios, who earned his bachelor’s degree in biological science in 2014.
Jamal, who completed his undergraduate degree in May, works with Kristy L. Forsgren, assistant professor of biological science, focusing on the oarfish’s reproductive biology. Through histological analysis of the ovary and testis tissue, their study is looking into the reproductive differences of the sexes, such as the male’s sexual maturity and the female’s fertility and timing of spawning.
A necropsy inside Forsgren’s lab of the ovaries of the female collected in June revealed an estimated 80 million eggs. What’s fascinating, they explained, is that the testes of the male collected in August were only 10 inches long and weighed less than a pound, when compared to the female’s massive ovaries.
“Because we know very little about this fish and its reproductive biology, we hope to significantly contribute to the understanding of the oarfish’s reproduction,” said Forsgren. “Through our research on the oarfish, students working in our laboratories are getting an incredible opportunity that will help to advance their research skills.”