Giving birds a starting date: The curious social solution to a water resource issue in the U.S. West

•Wyoming has a prior appropriation water rights system.•Recently, even birds have received a water right with a date - 1904.•What looks at first hand as path dependency can mean incremental institutional change.•Incremental change can be successful if it addresses challenges the institution faces.•Incremental change risks the build-up of pressure that may lead to a system collapse.•Confidence in the system and mental models favors incremental institutional change.

Examining a natural resource management system, we show that what first looks like rigid path dependency is actually stepped incremental change. The theoretical question then arises of whether it is possible to predict when a natural resource governance system will follow such an incremental path of institutional change. Our investigation of the prior appropriation water rights system as administered in the state of Wyoming reveals that mental models, based on factors such as strong personal connections with administrators, plus strong confidence in the system, tend to favor incremental change. We note that choosing incremental change is not without risk. While systems that undertake wholesale and rapid change risk a good deal - exposing themselves to a potential shower of unanticipated consequences - systems that follow the path of incremental change also take risks. Incremental change may mean successful accommodation of new needs that demand attention, or it may be “too little too late,” ultimately allowing the pent-up pressure of unmet needs to push the system over a threshold into collapse.