Tracking wetland restoration: Do mitigation sites follow desired trajectories?

Hypothetical models in the scientific literature suggest that ecosystem res toration and creation sites follow a smooth path of development (called a t rajectory), rapidly matching natural reference sites (the target). Multi-mi llion-dollar mitigation agreements have been based on the expectation that damages to habitat will be compensated within 5-10 years, and monitoring pe riods have been set accordingly. Our San Diego Bay study site, the Sweetwat er Marsh National Wildlife Refuge, has one of the longest and most detailed records of habitat development at a mitigation site: data on soil organic matter, soil nitrogen, plant growth, and plant canopies for up to 10 years from a 12-year-old site. High interannual variation and lack of directional changes indicate little chance that targets will be reached in the near fu ture. Other papers perpetuate the trajectory model, despite data that corro borate our findings. After reviewing "trajectory models" and presenting our comprehensive data for the first time, we suggest alternative management a nd mitigation policies.