An interesting tidbit from the Cornell website:
- The floating nest of the Franklin's Gull gradually sinks as the material below the water surface decays, and it requires continual maintenance. Both parents add new nest material daily until one or two weeks before departing the colony. Older chicks also add nest material from the immediate vicinity of the nest.
Franklin's Gulls molt twice a year so the feathers are always comparatively fresh compared with Laughing Gulls.