Presentation on theme: "Applications of long term fish monitoring in the Sacramento-San Joaquin River Delta to salmonid restoration efforts Rick Wilder Delta Juvenile Fish Monitoring."— Presentation transcript:
Applications of long term fish monitoring in the Sacramento-San Joaquin River Delta to salmonid restoration efforts Rick Wilder Delta Juvenile Fish Monitoring Program, U.S. Fish & Wildlife Service, Stockton, CA U.S. Fish & Wildlife Service Introduction Evaluating the effectiveness of an ecological restoration action is a critical, yet often overlooked, step in the restoration process (Bash & Ryan 2002). Documentation of success is often difficult or not financially feasible owing to high variation in natural ecosystems and the potentially long time frame needed for the ecosystem to respond (Shields et al. 2003). The use of baseline and reference monitoring data is crucial to a true evaluation of restoration success. Baseline data can: (1) identify and quantify the extent of an ecological problem, (2) suggest appropriate restoration solutions to the problem, and (3) should be used with post-restoration monitoring to evaluate success (Hood & Hinton 2003). Reference sites should be used as controls with which to compare a restored site after the restoration action. The Delta Juvenile Fish Monitoring Program (DJFMP) has monitored juvenile fish populations, with a particular focus on Chinook salmon, throughout the lower Sacramento and San Joaquin rivers, Delta, and San Francisco and San Pablo Bays since 1976. The purpose of this poster is to showcase potential applications of DJFMP data to the multiple salmonid restoration projects in the Delta and its upstream waterways. Literature Cited Bash JS, CM Ryan. 2002. Stream restoration and enhancement projects: is anyone monitoring? Environmental Management. 29:877-885 Hood WG, S Hinton, J Klochak. 2003. Baseline monitoring: planning, design, and prediction for estuarine habitat restoration. In: Proceedings of 2003 Georgia Basin - Puget Sound Research Conference Shields FD, CM Cooper, SS Knight, MT Moore. 2003. Stream corridor restoration research: a long and winding road. Ecological Engineering 20: 441-454 Methods Data are collected using three techniques: midwater trawls, Kodiak trawls, and beach seines (Fig. 1). The three trawl sites represent the upper (Sherwood Harbor in the Sacramento River, rm 55; Mossdale in the San Joaquin River, rm 54) and lower (Chipps Island in upper Suisun Bay) boundaries of the Delta (Fig. 2). Trawls are typically conducted 10 times per day, three days per week, year-round. Beach seines are conducted at 56 sampling locations throghout the region. In general, one seine is conducted at each site once per week, year-round. After each trawl tow and beach seine haul, all fish are removed from the net, identified to species, counted, measured, and released. All data are stored in a Microsoft Access database and are publicly available at. Application 1. Baseline or reference site data Most assessments of salmonid restoration projects in the Delta measure the effect on adult returns and production. We record life stage of all juvenile salmon we measure (yolk sac fry, fry, parr, silvery parr, and smolt). Fish in these critical stages undergo a variety of pressures as they migrate through the Delta, Estuary, and Bays toward the ocean. As a result, our data can be used as baseline or control information of each stage of juvenile salmon throughout the region. For example, a recent settlement agreement regarding the upper San Joaquin River recommends restoration of major portions (153 miles) of the San Joaquin River. The DJFMP conducts year-round beach seines at 14 sites on the lower San Joaquin River from Antioch Dunes (rm 1) to the Tuolumne River (rm 83; Fig. 2). Our work could provide excellent background data with which to compare the effects of these restoration actions on juvenile San Joaquin fall-run salmon and steelhead. Limitations Although there is great potential for using DJFMP data in monitoring the effectiveness of restoration actions, there are limitations: 1. The monitoring data are not action- or site-specific. As a result, they may be less precise in their utility. 2. We measure abundance, size, and condition of juvenile salmonids migrating downstream. If adult returns or production rates are the target measure of restoration action, these data will be less useful. Application 2. Adaptive management Although a relatively new concept, adaptive management can be an excellent tool for incorporating the scientific process into restoration actions. The adaptive management process consists of: (1) implementing a restoration action based on professional judgment and the best scientific data available; (2) monitoring the effectiveness of the action; and (3) modifying the action, if necessary and reasonable, to improve the effectiveness of the action. Restoration managers could use DJFMP data in the monitoring stage of the adaptive management process. Because we sample year-round, we can control for intra-year variation in effects of restoration on salmonids (i.e., fry and juveniles migrating downstream from all four races, which occur at different times of year). For example, we currently collect tagged salmon data for the Vernalis Adaptive Management Program (VAMP). The goal of the program is to determine the effects of the combination of water exports and flow rates on movement and survival of juvenile salmon in the Delta. Our data will be used by VAMP ultimately to decide upon the best management strategies to preserve salmon survival while maintaining acceptable water exports and flow rates. Application 3. Non-salmonid species One benefit of our program is that we record data about, not only Chinook salmon, but all fish species as well (Fig. 3). As a result, we have maximized the potential for future uses of our data. As the number of species of management concern increases, our database is well equipped to provide baseline or reference data towards future restoration projects aimed at conserving these species. For example, there has been much concern recently regarding a Delta-wide decline in multiple fish and invertebrate species. This “pelagic organism decline” has prompted high levels of interest to determine its causes, reverse the trend, and restore the populations. Our data can serve as baseline data both before and after the decline and, because we have multiple sites throughout the Delta, could prove useful in determining the spatial extent of the decline. (A) (B) Figure 1. Sampling types: (A) midwater trawl, (B) Kodiak trawl, (C) beach seine Photo: H. Webb (C) Photo: H. Webb Photo: P. Grant Figure 3. Fish species caught regularly in sampling: (A) Chinook salmon, (B) Sacramento splittail, (C) Delta smelt, and (D) assorted non-native species (A) (B) (C)(D) Photo: P. Voong Photo: K. Vargas Figure 2. Map of sites currently sampled by the DJFMP Suisun Bay San Francisco San Francisco Bay American River Cosumnes River Mokelumne River Calaveras River Stockton Stanislaus River Tuolumne River San Joaquin River Sacramento River Sacramento San Pablo Bay Trawl Seine Conclusion With 30 years of monitoring data on juvenile salmonid populations at 59 sites throughout the lower Sacramento and San Joaquin Rivers, the Delta, and San Pablo and upper San Francisco Bays, the DJFMP is well equipped to provide applicable data to a wide range of salmonid restoration projects.