Difference between revisions of "Green Sunfish Page"

NPS reported today the results of a survey they did last Friday (8/12/16) to follow up on a report earlier this month from AZGF that there may be green sunfish again in the Upper Slough in Glen Canyon. If you recall, an infestation of green sunfish in this slough was why an HFE was not held in the fall last year. NPS reported today: "Two Grand Canyon National Park technicians made a quick sample in the Upper Slough with a backpack electrofisher on Friday (August 12). Due to a river emergency downstream, they had limited time on site, but completed one sample (574 seconds) along the muddy shore on the river side of the slough. They captured 26 green sunfish and saw many more. Some captured green sunfish were in the 20 mm size range. A block net is still installed between the sloughs, but is compromised at current flows." NPS, Reclamation, USFWS, AZGF, and GCMRC are organizing to come up with both a short-term plan that addresses this latest infestation and to come up with a long-term fix for this problem. The hope is to have this addressed in some fashion before the end of the current HFE window as to not interfere with the possibility of conducting an HFE this fall. (8/16/16)

In July, 2015 AGFD biologists discovered an unusually large, reproducing population of invasive green sunfish in the slough. Green sunfish are prolific, with a single female producing up to 10,000 eggs. They are also voracious predators of native fish and their eggs. Biologists with the AGFD, NPS, USGS, FWS, and BOR determined that green sunfish pose a threat to native fish including the humpback chub (Gila cypha). A rapid response action is necessary to eradicate the population of sunfish before it spreads downstream into critical habitat for the endangered humpback chub. (2015 NPS Press Release)