collecting
By Jon Hare
fish stomach contents
from file cabinets
Field studies take a lot of effort. Think of studying fishes in an estuary – where a river meets the sea. You need the expertise to know the fishes and how to take the variety of biological samples including earbones, stomachs, and gonads. You need a boat and gear to catch fish of different sizes and habits. You need to be able to deal with weather, seasons, and the other elements of nature. You need a group of people with varying expertise committed to work together. You need funding for the project. And the field effort is just the beginning – samples need to be processed in the laboratory, data compiled and analyzed, the results published, and the data made available. Now think about how many field studies or parts of field studies never make it to those final steps of dissemination. What happens to these studies? What happens to all that effort?
Hanson and Courtenay (2020) describe the fate of one such effort. A multi-year fish-related field program was undertaken from 1991 to 1993 to describe the structure and function of the Miramichi River and Estuary ecosystem in eastern Canada. After several years, the project ended owing to a change in priorities (and funding); the team of scientists and fishers went their separate ways. Some of the results were published – primarily around high profile species like Atlantic cod and Atlantic salmon. However, many of the samples and much of the data never made it to the dissemination stage of science.
The study by Hanson and Courtenay is part of an effort to recover the large amounts of field data stored in old file cabinets, on floppy disks, and in unpublished theses. In their study, Hanson and Courtenay use data collected during the Miramichi Estuary program and present detailed descriptions of the stomach contents of more than 8,000 individual fish across a range of species. Through these analyses, they describe the seasonality in the estuary both in terms of fish occurrence and diet. They also identify a small shrimp species (Crangon septemspinosa – Seven-spined Bay Shrimp) as a keystone species, linking estuarine and coastal foodwebs. Although the findings are not earth-shattering, the results and data are now available for future studies, which could model foodweb dynamics in the ecosystem (e.g. using EcoPath) or document ecosystem changes over the past three decades (a neat example from Long Island Sound, USA). Field studies and the subsequent research based on field studies are essential to developing strategies for ecosystem resilience and climate adaptation and ultimately for living sustainably within the earth system.
Original research: Hanson, J. M., & Courtenay, S. C. (2020). Data Recovery from Old Filing Cabinets: Seasonal Diets of the Most Common Demersal Fishes in the Miramichi River Estuary (Atlantic Canada), 1991–1993. Northeastern Naturalist, 27(3), 401-433. https://doi.org/10.1656/045.027.0302
Dr. Jon Hare is a scientist who works in Woods Hole, Massachusetts. His research background is fisheries oceanography and climate change impacts on marine fisheries. Check out Jon’s other sciku ‘Owls of the Eastern Ice’, ‘Varves’, ‘Signs of Spring’ and ‘Glacier Mice‘.