Rehabilitating Habitat on the Upper Gila River
Bethany Drahota1*, Steve Plath2, Melanie Tluczek3,
1 Gila Watershed Partnership of Arizona, Safford, AZ, USA; bethany@gwpaz.org
2 Gila Watershed Partnership of Arizona, Safford, AZ, USA; steve.plath@gwpaz.org
3 Gila Watershed Partnership of Arizona, Safford, AZ, USA; melanie@gwpaz.org
How practitioners deal with riparian rehabilitation in the southwest has changed markedly over the last decade. Both climatic and anthropogenic influences have drastically altered landscape appearances and conditions, making sustainable restoration a moving target. Restoration in the Upper Gila Watershed is largely dictated by the presence of the exotic salt cedar tree (tamarisk; Tamarix spp.), which has infiltrated the floodplain and altered the vegetation structure and biodiversity, as well as influenced hydrologic functions. Within this area, the Gila Watershed Partnership (GWP) aims to control tamarisk cover in pockets along the river in an effort to reduce wildfire risk and re-establish native habitat conditions for sensitive wildlife species, including the endangered southwestern willow flycatcher (Empidonax traillii extimus) and the threatened yellow-billed cuckoo (Coccyzus americanus). Restoration in this area is critical, as the tamarisk leaf beetle (Diorhabda spp.) is rapidly expanding its territory and threatens to remove important nesting habitat before native tree species have a chance to regenerate into viable nesting areas. However, rehabilitating habitat in the arid southwest is replete with challenges, and as a result, the GWP has a strong emphasis on adaptive management. Key challenges in this project include limited access to water, deep and fluctuating groundwater depths, extreme summer temperatures, endangered species act regulated work seasons, intense herbivory pressures on newly planted seedlings, delays and changes in bi-annual rainfalls, and the expense and effort involved in controlling both tamarisk and extreme densities of secondary weeds. This presentation will address the adaptive actions used by the GWP to mitigate challenges, attempt to assess GWP’s success, and evaluate necessary future adaptations in areas where success was limited.