Importance/Issues

Ephemeral and intermittent drainages serve as critical habitat and travel corridors for resident and migratory species in the Sonoran Desert and Apache Highlands ecoregions, and provide important ecosystem services such as flood dissipation, sediment transport, and habitat connectivity. Ephemeral and intermittent drainages also provide insights into the processes and conditions of the watersheds they drain.

Parks Monitored

Chiricahua NM, Coronado NMem, Fort Bowie NHS, Organ Pipe Cactus NM, Saguaro NP, Tonto NM

Monitoring Objectives

For major intermittent and ephemeral washes, we will determine the status of and detect trends in:

Stream channel morphology (over 5-year intervals or following a 50-year flooding event).

Common (>25% abolute plant cover) native and non-native plant species and all perennial plant lifeforms within floodprone areas of major washes (over 5-year intervals or following a 50-year flooding event).

Potential Measures

Channel morphology: Channel width x depth ratio; cros section area; sinuosity, channel slope and sediment compostion.

Riparian plant communities: plant alliance type and distribution; community similarity measures over time and space.

Riparian plant species and lifeforms: % vegetative cover for common (>25% absolute cover) perennial plants and perennial plant lifeforms; % frequency of uncommon (<25% absolute cover) perennial plants and annual plant lifeforms.

Determine the occurance and long-term trends in the frequency of selected non-native, invasive perinnial and annual species.

Management Applications

Major washes are important focal resources for the parks where they occur. Managers can use monitoring information to guide park management actions and to address proximate issues that are occurring within park boundaries. Wash monitoring information also provides an index of overall watershed condition, providing park managers with information to effectively address broad-scale issues with adjacent land owners and other land management and regulatory agencies. Finally, wash conditions provide insights into broader landscape conditions due to the critical ecological services these systems support over surrounding terrestrial landscapes - services that are greatly disproportionate to the relatively meager area of these riparian corridors.

Protocol Development Status

This protocol will be drafted and tested in 2008 & 2009. Pilot studies at ORPI and TONT will be completed.

Status & Trends

This protocol is currently in development; no status or trend information is currently available.

Project Leads

Evan Gwilliam, Ecologist (Aquatic)
Cheryl McIntyre, Sonoran Institute Ecologist