Now that we're back at Clemson, the next (indoor) chapter of the project has begun. Last week, we started sorting through the diet samples regurgitated by the pelicans we captured. Some contained recognizable fish, while others were too digested to identify. To process these, we'll have to dissolve the fish tissue, collect the bones, and pick out otoliths (inner ear bones) that can help us identify fish species and even determine the size of the individual fish. For the less-digested samples, however, processing was much easier: we thawed the frozen mass of fish, separated out individual specimens, and weighed, measured, and photographed each one.
| Samples contained anywhere from one to 100 or more individual fish, ranging in size from a few centimeters to over 40 cm (more than a foot). |
In most cases, the fish were well-preserved enough for us to identify them to species based on physical characteristics. We may even be able to use some of the best samples to test nutrient composition and caloric density to see how different species might contribute differently to the energy needs of a pelican. In the meantime, it was interesting to begin comparing the diets of pelicans in our different study areas and seeing some unexpected diversity. | |
We still have a lot of work to do identifying and analyzing our fish, but it's a fun (although smelly) process. More to come!