Glen Canyon Dam Adaptive Management Program Administrative History

While the ecology and evolution of partial migratory systems (defined broadly to include skip spawning) have been well studied, we are only beginning to under- stand how partial migratory populations are responding to ongoing environmen- tal change. Environmental change can lead to differences in the fitness of residents and migrants, which could eventually lead to changes in the frequency of the strategies in the overall population. Here, we address questions concerning the life history of the endangered Gila cypha (humpback chub) in the regulated Colorado River and the unregulated tributary and primary spawning area, the Little Colorado River. We develop eight multistate models for the population based on three movement hypotheses, in which states are defined in terms of fish size classes and river locations. We fit these models to mark–recapture data col- lected in 2009–2012. We compare survival and growth estimates between the Col- orado River and Little Colorado River and calculate abundances for all size classes. The best model supports the hypotheses that larger adults spawn more frequently than smaller adults, that there are residents in the spawning grounds, and that juveniles move out of the Little Colorado River in large numbers during the monsoon season (July–September). Monthly survival rates for G. cypha in the Colorado River are higher than in the Little Colorado River in all size classes; however, growth is slower. While the hypothetical life histories of life-long resi- dents in the Little Colorado River and partial migrants spending most of its time in the Colorado River are very different, they lead to roughly similar fitness expectations when we used expected number of spawns as a proxy. However, more research is needed because our study period covers a period of years when conditions in the Colorado River for G. cypha are likely to have been better than has been typical over the last few decades.

ABSTRACT: The Colorado River below Glen Canyon Dam, Arizona, is part of an adaptive management programme which optimizes dam operations to improve various resources in the downstream ecosystem within Grand Canyon. Understanding how populations of federally endangered humpback chub Gila cypha respond to these dam operations is a high priority. Here, we test hypotheses concerning temporal variation in juvenile humpback chub apparent survival rates and abundance by comparing estimates between hydropeaking and steady discharge regimes over a 3-year period (July 2009–July 2012). The most supported model ignored flow type (steady vs hydropeaking) and estimated a declining trend in daily apparent survival rate across years (99.90%, 99.79% and 99.67% for 2009, 2010 and 2011, respectively). Corresponding abundance of juvenile humpback chub increased temporally; open population model estimates ranged from 615 to 2802 individuals/km, and closed model estimates ranged from 94 to 1515 individuals/km. These changes in apparent survival and abundance may reflect broader trends, or simply represent inter-annual variation. Important findings include (i) juvenile humpback chub are currently surviving and recruiting in the mainstem Colorado River with increasing abundance; (ii) apparent survival does not benefit from steady fall discharges from Glen Canyon Dam; and (iii) direct assessment of demographic parameters for juvenile endangered fish are possible and can rapidly inform management actions in regulated rivers.

Federal advisory committees — which may also be designated as commissions, councils, or task forces — are created as provisional advisory bodies that can circumvent bureaucratic constraints to collect a variety of viewpoints on specific policy issues. Advisory bodies have been created to address a host of issues, ranging from policies on organ donation to the design and implementation of the Department of Homeland Security. These committees are often created to help the government manage and solve complex or divisive issues. Such committees may be mandated to render independent advice or make recommendations to various bodies within the federal government by congressional statute, created by presidential executive order, or required by fiat of an agency head.

Congress formally acknowledged the merits of using advisory committees to acquire viewpoints from business, academic, governmental, and other interests when it passed the Federal Advisory Committee Act (FACA) in 1972 (5 U.S.C. Appendix — Federal Advisory Committee Act; 86 Stat.770, as amended). Enactment of FACA was prompted by the belief of many citizens and Members of Congress that such committees were duplicative, inefficient, and lacked adequate control or oversight. Additionally, some citizens believed the committees failed to sufficiently represent the public interest — an opinion punctuated by the closed-door meeting policies of many committees. FACA mandated certain structural and operational requirements for many federal committees, including formal reporting and oversight procedures for the advisory bodies. FACA requires that committee membership be “fairly balanced in terms of the points of view represented,” and advice provided by committees be objective and accessible to the public. Additionally, FACA requires nearly all committee meetings be open to the public. Pursuant to statute, the General Services Administration (GSA) maintains and administers management guidelines for federal advisory committees. During FY2008, GSA reported a total of 917 active committees with nearly 64,000 total members that provided advice and recommendations to 50 federal agencies. The total operating costs for these committees in FY2008 was $344.3 million. Agency administrators, the President, and Congress continue to create federal advisory committees in the 111th Congress.

Committees that fit certain FACA criteria and are created by the executive branch are governed by FACA guidelines. FACA was designed to eliminate duplication of committee expertise and make advisory bodies in the executive branch more transparent. Congress may decide, however, to place FACA requirements on a body that it statutorily created. Existing statutes are sometimes unclear as to whether a congressionally created committee would have to comply with FACA requirements — except in cases when the statute explicitly mandates FACA’s applicability.

Legislation (H.R. 1320) was reintroduced in the 111th Congress that would require members of advisory committees be selected without regard to their partisan affiliation. Also pursuant to the legislation, executive branch agency heads would be authorized to require members serving on agency advisory committees to fully disclose any actual or potential conflicts of interest. Additionally, GSA’s Administrator would be given authority to create regulations and guidelines to further ensure that an advisory committee offered impartial advice and recommendations. The bill would also require each advisory committee to create a website, publish advance notice of meetings, and provide public access to proceedings on its website. The bill was sent to the House Committee on Oversight and Government Reform, and ordered to be reported from the committee on March 10, 2009. Similar legislation was introduced in the 110th Congress (H.R. 5687), but was not enacted.

With a focus on resources of the Colorado River ecosystem below Glen Canyon Dam, the Glen Canyon Dam Adaptive Management Program has included a variety of experimental policy tests, ranging from manipulation of water releases from the dam to removal of non-native fish within Grand Canyon National Park. None of these field-scale experiments has yet produced unambiguous results in terms of management prescriptions. But there has been adaptive learning, mostly from unanticipated or surprising resource responses relative to predictions from ecosystem modeling. Surprise learning opportunities may often be viewed with dismay by some stakeholders who might not be clear about the purpose of science and modeling in adaptive management. However, the experimental results from the Glen Canyon Dam program actually represent scientific successes in terms of revealing new opportunities for developing better river management policies. A new long-term experimental management planning process for Glen Canyon Dam operations, started in 2011 by the U.S. Department of the Interior, provides an opportunity to refocus management objectives, identify and evaluate key uncertainties about the influence of dam releases, and refine monitoring for learning over the next several decades. Adaptive learning since 1995 is critical input to this long-term planning effort. Embracing uncertainty and surprise outcomes revealed by monitoring and ecosystem modeling will likely continue the advancement of resource objectives below the dam, and may also promote efficient learning in other complex programs.

An Adaptive Environmental Assessment and Management workshop process was used to assist Grand Canyon scientists and managers in developing conceptual and simulation models for the Colorado ecosystem affected by Glen Canyon Dam. This model examines ecosystem variables and processes at multiple scales in space and time, ranging from feet and hours for benthic algal response to diurnal flow changes, to reaches and decades for sediment storage and dynamics of long-lived native fish species. Its aim is to help screen policy options ranging from changes in hourly variation in flow allowed from Glen Canyon Dam, to major structural changes for restoration of more natural temperature regimes. It appears that we can make fairly accurate predictions about some components of ecosystem response to policy change (e.g., autochthonous primary production, insect communities, riparian vegetation, rainbow trout population), but we are moderately or grossly uncertain about others (e.g., long-term sediment storage, response of native and non-native fishes to physical habitat restoration). Further, we do not believe that existing monitoring programs are adequate to detect responses of native fishes or vegetation to anything short of gross habitat changes. Some experimental manipulations (such as controlled floods for beach/habitat- building) should proceed, but most should await development of better monitoring programs and sound temporal baseline information from those programs.