Thanks to my former botany/biology instructor April Fong, the National Science Foundation, and COSEE-PRIME, I am currently working with the Oregon Department of Fish and Wildlife (ODFW) at Hatfield Marine Science Center (HMSC) in Newport, Oregon with shellfish guru Mitch Vance in a study of the phenomenon of fat gaper clam (Tresus capex) reburial. Gaper clams are prized by recreational clam-diggers because they can grow up to 8 inches in shell length. Current ODFW regulations state that a harvester has catch limit of 12 gaper clams per day and they must be retained regardless of size or condition. The purpose of my research was to examine their burrowing behavior above and below the sediment after they are harvested.Above (upper left) is a picture of me at Idaho Flat (a mud flat directly adjacent to HMSC), during high tide with some freshly-hauled experimental units (photo by Mitch Vance). This method of sediment collection was easier and more efficient than the one used the previous morning. I don't recommend dragging two 5 gallon buckets of mud across the flat with a sled- the units are very heavy and traversing the mud in this fashion takes a significant amount of physical strength.
T. capax has several common names, including empire, horse and blue clam. In Yaquina Bay the common name is gaper clam or simply gaper. Note the opening in the shell that accommodates its prodigious neck (center, photo obtained via google search from wallawalla.edu). Its close relative, the Pacific gaper clam (Tresus nutttallii), is virtually absent in Yaquina Bay but more abundant in California estuaries. One of the easiest ways to tell the difference between a gaper and geoduck (Panope generosa) is by the presence of two leathery plates at the end of the gaper's neck.
We collected 6 gapers during low tide at Idaho Flat on June 24th, recorded their weights and shell lengths, tagged them with ID numbers, and relocated them to an outdoor open system seawater tank. We placed three specimens on the surface of the sediment of one bucket and and planted the rest in a second bucket so that the tops of their shells were somewhat level with the sediment surface. Planting the second group made the water turbid, but I have a photo of the surface group taken about 40 minutes after the beginning of the experiment (right).