A few years ago, Cal Poly undergraduate Emily Knighton conducted a pilot tagging study of Pismo clams as part of her senior project. She developed methods to mark them, tested finding them (with a metal washers and a metal detector!), and then marked 50 clams and put them back on the beach. A month later, we went back to look, but a series of swells had rearranged the beach. We found none, and thought they were gone forever...
...until this month, when someone found one of our marked shells, posted a picture on social media, and the social media science world helped us connect. Clam #18 was 57mm when it was tagged on Dec 8, 2018, and the shell was found on Oct 11, 2020, almost two years later! It was dead (but with hinges still attached, so probably hadn't been dead long) and it had grown to 77mm. So not only do we get a little growth data, but we have evidence that the tags will last at least 2ish years. We will try again, so stay tuned for more info. And, if you happen to find a marked clam, please let us know!
Noel Clark presented a talk at the Pacific Coast Shellfish Grower Association (PCSGA) and National Shellfisheries Pacific Coast Section (NSA-PCS) joint virtual conference! Her talk "Age and growth of the Pismo clam (Tivela stultorum) in California" shared findings from her summer FROST internship and senior project.
Noel was awarded an honorable mention for Best Student Presentation! Congratulations Noel!
COVID-19 has created challenges for us all, but we've found creative ways as a lab community to adapt and continue pursuing research and marine science education in a sage setting.
We're presenting research at virtual conferences, adapting undergraduate summer research positions to focus on building student's skills in fisheries data analysis and scientific communication, and finding creative ways to continue engaging students in hands-on research in a socially distanced setting.
Check out Dr. Ben Ruttenberg teaching 'BIO 322: Ichthyology' undergraduate students about fish dissections in a pop-up outdoor lab! We imagine this is a major improvement to the olfactory system as students learn about the anatomy and identification of these "pickled" fishes.
Our lab is excited to welcome Marissa Bills as a Master's student in September of 2020. Before joining the Cal Poly Marine Conservation Lab, Marissa was a Laboratory Assistant for California Sea Grant. Marissa's past research has focused on marine aquaculture and conservation. She will be continuing the lab's research on Pismo clams populations in California and is exploring the aquaculture potential of this species.
As part of the Cal Poly Frost Summer Undergraduate Research Program, Ellie worked with master's student Erin to study 'The Effects of Marine Heatwaves on Sebastes mystinus Growth Rate' and Abby worked with master's student Hannah to study 'Coprophagy by Herbivorous Fishes in the Caribbean'. The two recently presented their findings at the Frost Summer Research Symposium.
The Effects of Marine Heatwaves on Sebastes mystinus Growth Rate
This summer, Ellie analyzed age-at-length data for Blue rockfish during the 1982-1983 El Niño to determine the relationship between anomalous warm water events and growth rate. She constructed Von Bertalanffy growth curves before, during, and after the El Niño and found that growth appears to slow during and after warm water events for this fish species. Future directions this study could take include examining growth curves of other temperate fishes during warm water events and combining multiple datasets into a powerful predictive tool for estimating growth rates during future climate anomalies.
Coprophagy by Herbivorous Fishes in the Caribbean
Abby analyzed feces consumption (or 'coprophagy') by herbivorous parrotfishes and surgeonfishes in the Caribbean. She found that while there are species-specific differences in rates of coprophagy, the majority of species engaged in coprophagy to some extent. To determine the nutritional drivers of this behavior, Abby helped develop a lab protocol to analyze the nutritional breakdown of targeted fecal pellets. Over the next year, she will work to analyze these fecal samples and report on these findings for her senior research project, supported by a Cal Poly Baker/Koob award.
Congratulations on concluding this exciting summer research!
We extend our deepest thanks to William and Linda Frost for their generous funding of undergraduate research that helped to support this research. We look forward to sharing our findings with the broader community in the future.
Check out our recent publication on the 'Impacts of parrotfish predation on a major reef-building coral: quantifying healing rates and thresholds of coral recovery' in Coral Reefs! A read-only open access version is available here: https://rdcu.be/b5Vgl
Summary: We monitored coral tissue regeneration from parrotfish predation scars on endangered Orbicella annularis coral colonies on St. Croix and Bonaire in the Caribbean. We evaluated differences in coral healing between islands in response to a number of variables including the initial scar surface area, scar abundance per coral colony, colony surface area, and water depth. We found that initial scar surface area was the single most important predictor of scar healing and used a predictive model we developed to estimate coral tissue loss from the standing stock of bite scars. Overall, our results suggest that the majority of scars may fully heal and the immediate negative impacts of parrotfish predation on coral tissue loss appear to be driven primarily by a few exceptionally large bite scars.
We are excited to share this video talk by master's student Hannah Rempel as part of the Global Coral Reef Week conference. Learn about the patterns of coral healing from parrotfish bite scars in one of the most intensively grazed Caribbean coral species:
Well, we're a collection of science-minded marine misfits. But we're always up to something...