b"HUMPBACK CHUB: THE TALE OF A GRAND CANYON NATIVE FISH SPECIESBy Emily Higueraon yT Pe Emily Higuera is an Environmental Programs hSpecialist for the Colorado River Management Section. She participates on behalf of the 2nd Hand Store department in a number of programs, including the Glen Canyon Dam Adaptive Management Program, which focuses on We Collect & Deliverenvironmental compliance upstream of Lake MeadHumpback Chub (Gila cypha)to Lake Powell, as well as the Lower Colorado River Your Merchandise Multi-Species Conservation Program, which providesIllustration by Joe TomelleriFREE LOCAL DELIVERY AVAILABLE compliance at Lake Mead to the Southern International Boundary. Emily has always had a birds eye view of thefish have survived for millions of years. The extraordinary 662 W. Wickenburg WayGrand Canyon, until her trip with the Glen Canyon Damhumpback chub has survived periods of low flows to WickenburgOpen MondaySaturday Adaptive Management Group in June of 2022. That riverextreme floods and navigated highly turbid waters. As one experience, she said, truly encapsulated the depth andmight guess by the name, the humpback chub (Gila cypha) thepony2ndhandstore.com wonder that is the Grand Canyon. evolved to form a distinctive, fleshy hump behind their 928-231-2730928-232-2019 T he Grand Canyon is renowned for its geologicalheads. This adaptation allows the species to stabilize andWe Carry Quality 2nd Handmaintain positions in difficult water conditions, as well structures and historic human explorations, but lessas increase survival from co-evolved predators, such as & New Merchandise is known of the endemic fishthe humpback chub -the Colorado pikeminnow. The humpback chub evolved Your Home Furniture Supplies Store that adapted to survive the grueling pre-dam conditionsaround 3.5 million years ago and remained undiscovered Specializing in Appliances of the Colorado River.until 1933. Humpback chub can live more than 30 years and reach 20 inches in length. Jane and Peter Kibble To truly understand the challenges and whats at stake pony2ndhandstore@outlook.comfor the humpback chub, ADWR staff explored theThe humpback chub has experienced many hardships since Grand Canyon through the Glen Canyon Dam Adaptivethe damming of the Colorado River and its tributaries. Management Program for 10 days in mid-June of lastPost-dam conditions brought stabilized flows and clear year. The rafting trip began at Lees Ferry and took out atwater conditions, creating a foreign environment for the Diamond Creek. ADWR participates in the program as alarge minnow species. The development of reservoirs Colorado River Basin State representative. also provided fishing opportunities that would otherwise be unavailable in the desert, bringing many nonnative, The Canyon has sustained species for millions of years.highly predatory fish into the Colorado River Basin. Their However, much has changed since the installation ofintroduction has impacted the upper basins populations Glen Canyon Dam: stocked rainbow trout wait patientlyof the threatened species. The cooler release temperatures for lunch leftovers and New Zealand mudsnails litter thefrom Glen Canyon Dam created a Blue Ribbon Trout banks where nonnative vegetation had often overtakenFishery that has also increased concerns of predation on the shoreline. Some natives still remain: flannel mouththe humpback chub where the species overlap. suckers investigate the shallow waters while bighorn sheep graze on the beaches. Fossils in the canyon wallsThe Grand Canyons population of humpback chub has and 50,000 year-old packrat mittens provide evidence ofbeen predominant in the Little Colorado River, with prehistoric life in the Grand Canyon. Past and present, themovement into the mainstem and downstream tributaries. canyon teems with life. Lake Powells low elevations have increased water release temperatures, providing more opportunities for humpback Our trip focused not only on the ecosystem, but alsochub habitat in the mainstem. This is a double-edged its anthropological history. Eleven tribes historicallysword, as the lower reservoir elevations have increased the utilized the Canyon and consider the Colorado Riverpassage of nonnative fish from Lake Powell into the river and its tributaries a place of origin, growth, and healing.below. Many of these warmwater fish have the capability to While our programs mission is focused on resourcedetrimentally effect, and potentially wipe out, this native management, the tribes provide traditional knowledgespecies from the Grand Canyon. and have been stewards of the Canyon for many years.ADWR has been working with federal, state and external We first encountered the humpback chub at thepartners to develop strategies and provide support to confluence of the Little Colorado River, a point in theprotect the Grand Canyon native and ensure the survival river known as River Mile (RM) 61. The fish were visibleof the humpback chub, while maintaining the continued from the bank, anticipating scraps from dinner. Well-fed,delivery and protection of Arizonas water resources.these fish were all too willing to receive food from the hands of campers. They werent alone. Among the chub were nonnative fish, including a large common carp, a species that has been shown to feed on larva chub. After a night under the star-flooded sky at RM 61, it was only a short hike into the canyon of the Little Colorado River. Following heavy rains, the water looked like chocolate milk compared to the beautiful turquoise often seen in picturesque portraits of the area. We could easily see young humpback chub in the shallow waters, indicating a successful spring spawn. This environment was much harsher than the mainstem, with steep walls and narrow beaches, highlighting the conditions these Lee's Ferry, Colorado River. Image Courtesy of Alan Schmierer CC0, via Wikimedia Commons18 July 2023"