From Chelsea Thompson, City of Petaluma Public Works & Utilities Department:
The Shollenberger dredge disposal site has maintenance requirements in order to be used for dredge disposal during dredge events on the Petaluma River. The Shollenberger Marsh Management, Maintenance and Monitoring Plan was approved by USFWS in 2014 and requires annual maintenance of pickleweed in the dredge disposal site by removal or mowing. This maintenance is to ensure the safety of the Salt Marsh Harvest Mouse during dredge disposal events. A biologist is walking in front of the mower to help move the mice and other critters out of the way. The goal is to get the animals to move to another location before the ponds get flooded with dredged water and mud.