How to photograph shellfish so they can be identified: three views and a ruler
Many shellfish are hard to identify to species from a single photo taken from above. Shell shape changes with the substrate and growing conditions: the same oyster on a rock and on a farm raft can look completely different. Photographing the right parts gives other identifiers something to work with. (Editorial sample article; admins can edit or delete it.)
At least three photos of each individual
- Outside of the left valve: the full outline, radial ribs and growth lines.
- Outside of the right valve: in scallops and other unequal-valved species, the two sides often differ in colour and convexity.
- Inside of the shell: adductor muscle scars, the pallial line, hinge teeth and ligament are key features for many bivalves.
Add a ruler
Shell height and length separate many similar species and record the size at the same time. Lay the ruler next to the shell, in the same plane, and keep the camera as square to it as you can.
Light and background
- Use soft, even light and avoid harsh midday sun and glare.
- Use a plain background: dark behind pale shells, pale behind dark ones.
- Wet shells look closer to their living colour, so spray a little seawater before shooting.
Add a line when you upload
Put shell height (mm), substrate and depth in the notes. For identifiers, these details often matter as much as the photo.
If you are unsure of the species, identify to genus or family first; that helps more than guessing a species name.