By – Stuart Wells, Director of Conservation and Science at the Phoenix Zoo
Drought, water draws, and introduced species can significantly impact the sustainability of terrestrial and aquatic native species. However, there is hope for the continued survival of many threatened or endangered species in Arizona thanks to the efforts of dedicated biologists with the Arizona Game and Fish Department and their partners who work tirelessly to manage and recover these species.
The Arizona Center for Nature Conservation, which oversees the Phoenix Zoo and its Conservation and Science Department (PZCSD), works in collaboration with the Department to support their efforts to conserve native terrestrial and aquatic species. The aquatic species we work with include Three Forks (Pyrgulopsis trivialis) and Page springsnails (Pyrgulopsis morrisoni), Chiricahua leopard frogs (Lithobates chiricahuensis, CLF), narrow-headed gartersnakes (Thamnophis rufipuntatus, NHGS) and several native fish species: desert pupfish, Gila topminnow, and Gila chub.
Through our CLF head-starting program, begun in 1995, we have reared and released over 25,000 juvenile leopard frogs and tadpoles into the wild, and over 17,000 from 2007 to present. AGFD reports that since 2007, active wild CLF populations have increased from 31 to 151 in 2016, a 400 percent increase. We are proud to have played a role in this positive conservation story.
Narrow-headed gartersnakes have been on the decline in the wild for over a decade. In 2014, 20 NHGS were born at PZCSD, the first-ever reproduction of this species in managed care. Subsequently, 10 of these snakes were released into the wild in 2016. PZCSD has partnered with University of Arizona School of Nature Resources and the Environment to develop a Native Species Conservation Doctoral Fellow program. Our first fellow joined us in fall 2016 and is conducting a life cycle assessment of these released snakes for his Ph.D.
Our native fish propagation program goal is to produce fish for the Department to use to augment wild populations. We provide desert pupfish and Gila topminnow each year to Department biologists that they transport into wild sites that need augmentation. In 2016, we provided 2173 fish to the Department for repopulating wild sites and starting new resource population. Our efforts are having an impact. One site that where Gila topminnow was extirpated are showing signs of reestablishing. A survey conducted of the site before adding new fish, revealed at least 200 fish remained from an initial reintroduction two years previous. Recently, PZCSD began working with the Roundtail Chub (Gila robusta). We received 36 fish that Department biologists collected from a wild site, and placed these fish into a specially designed, fully enclosed outdoor pond at the Phoenix Zoo. We have observed fry already this season, and have hopes of producing much more young to provide the Department with a supply of this species for release as needed throughout the species’ range in the wild.
The Arizona Center for Nature Conservation and Phoenix Zoo are honored to be trusted contributors to the conservation of so many native species in Arizona. We will continue working to provide the Department with healthy species raised specifically to survive reintroduction and translocation into the wild.