Approved March 11, 1997
The Cantara Trustee Council (CTC) recognizes the need for continued studies and monitoring of aquatic resources on the upper Sacramento River that were damaged as a result of the 1991 Cantara Spill. These studies are necessary to provide vital information for adaptive management as part of the CTC recovery and restoration programs; document recovery of resources; identify resources needing further restoration; develop easily repeatable techniques in the event of future spills on the river and other systems nationally; and establish baseline populations of aquatic resources for the river.
The Cantara Settlement Memorandum of Agreement (MOA) identifies the Study and Research Category as the lowest priority for expenditure of settlement funds administered by the CTC. The low priority for study and research funding is reflected in the CTC expenditure plan. In developing the grant application package, the CTC purposefully gave high weights for on-site and in-kind study and research projects to focus expenditure of funds in this category to the upper Sacramento River. Since study and research is the lowest priority for funding by the MOA, it is important for the CTC to focus expenditures on projects that will benefit the damaged resources of the river.
This plan identifies aquatic and fishery studies that the CTC believes are priorities for use of funds from the Upper Sacramento River Account. The highest priority projects are those that will provide critical information to manage the recovering fishery resources and will guide further restoration activities on the upper Sacramento River. Projects that largely document recovery of injured aquatic resources should be a lower priority.
|GOALS AND OBJECTIVES|
|1.||Meet the requirements of the MOA by focusing the expenditure of study and research dollars on high priority projects.|
|2.||Provide guidance for future Natural Resource Damage Assessments (NRDA) by establishing baseline data and developing rigorous repeatable techniques for resource evaluation.|
|3.||Support recovery, restoration, management and enhancement activities for natural resources injured by the Cantara Spill through collection of critical information.|
|4.||Document the effectiveness of restoration projects through performance monitoring.|
Following the Cantara Spill, the Department of Fish and Game (Department),
as lead Trustee, initiated a NRDA. Research studies were conducted by the
Department's Cantara Program and consultants to identify and quantify damage
to the natural resources of the upper Sacramento River. Monitoring of aquatic
taxon groups has been ongoing to document and determine the recovery status
of these groups. To identify natural resources that would benefit from
further restoration and monitoring, a taxon by taxon review of previous
and current research and monitoring studies of aquatic groups is provided.
This discussion should assist the CTC with setting priorities for future
funding in the Study and Research Category.
Periphyton surveys were completed on the river in 1991 by consultants
working for the Cantara Program. Periphyton
recovered very rapidly following the spill and further study would be of questionable value.
Benthic macroinvertebrate surveys were conducted between 1991 and 1993
by the Department of Water Resources (DWR) under contract with the Cantara
Program. DWR also collected samples in 1994 and 1995 without funding, but
these samples have not been analyzed. The CTC funded DWR with a grant to
collect and analyze benthic macroinvertebrates on the river in 1996. While
the results of the 1996 surveys were still pending at the time this plan
was written, indications are that macroinvertebrates have substantially
recovered. The value of conducting further benthic macroinvertebrate surveys
would be twofold. First, the data would be used to establish baseline conditions
in the event of future spills. Second, the data would be useful to fully
document recovery times for benthic macroinvertebrates for use in future
Mollusc surveys were completed on the river between 1992 and 1994 by Deixis Consultants under contract with the Cantara Program. No funding was available in 1995, but the CTC funded surveys in 1996 by Deixis with its first grant cycle. These surveys have indicated that recovery for molluscs has been slow and may require decades without intervention. Restoration of molluscs may be warranted under the CTC program.
During the 1996 grant cycle, Deixis proposed the reintroduction of four mollusc species into the upper Sacramento River that were extirpated as a result of the Cantara Spill. The source populations for reintroduction would have come from the Pit River. The CTC did not fund this restoration project because of the unknown potential for introduction of fish diseases from the Pit River into the upper Sacramento River. Pit River Rainbow Trout are known to be resistant to the Ceratomyxa parasite that is present in the Pit River. Upper Sacramento River Rainbow Trout are not resistant to Ceratomyxa, and relocation of molluscs from the Pit River, which could be intermediate hosts for many fish diseases, was considered too risky.
Deixis has proposed an alternative restoration project in 1997 where three species of molluscs would be relocated from the McCloud River system into the upper Sacramento River. The McCloud River drainage is adjacent to the upper Sacramento River, and the potential risk of introducing diseases from one to the other is much reduced. The CTC may wish to consider funding in situ bioassays using trout from the upper Sacramento River and exposing these fish to the McCloud River to rule out any disease potential from the relocation of molluscs.
The value of further mollusc monitoring on the river is threefold. First,
the data would be used to establish baseline conditions in the event of
future spills. Second, the data would be useful to document recovery times
for molluscs for use in future Natural Resource Damage Assessments. Finally,
monitoring provides information needed to design and implement a mollusc
restoration plan for the upper Sacramento River.
Crayfish surveys were conducted by Environmental Research Associates
in 1992 and 1993 under contract with the Cantara Program. The nonnative
species Pacifasticus leniusculus showed little sign of recovery,
but surveys were suspended to concentrate limited funds on native species
and more economically important species. While the CTC does not anticipate
funding restoration efforts for this nonnative crayfish species, further
monitoring would be valuable to establish baseline population levels and
recovery times for this species.
Carcass surveys indicated that riffle sculpin was the most abundant
fish species in the river prior to the spill. Standard snorkel surveys
conducted by Thomas R. Payne and Associates (TRPA) for the Cantara Program
were not adequate to address the recovery of this ecologically significant
species. TRPA developed intensive quadrat sampling techniques to monitor
riffle sculpin in 1994 and 1995. A pilot restoration program was approved
in 1994 where nearly 1,200 sculpins were captured in the river above the
spill site and relocated to two sites downstream. The relocation effort
was successful in establishing sculpin at sites where they were previously
absent. The CTC has funded TRPA to continue monitoring the recovery in
1996 and 1997. Riffle sculpin numbers are continuing to increase throughout
the river and no further restoration efforts will be necessary. Depending
on the 1996 and 1997 results, the CTC may wish to fund an additional year
of sampling toward the end of its program to establish baseline population
levels and recovery times for this species.
Wild Rainbow Trout Fishery
The fishery studies conducted by the Cantara Program on the upper Sacramento River have been imperative to managing the fishery since the spill, particularly with regard to angling regulations. Angling regulations have been the primary tools used to restore the wild trout fishery to date.
Thomas R. Payne and Associates (TRPA) mapped river habitats in 1991 following the spill, and have updated the mapping each year during the snorkel surveys. The habitat mapping has provided a valuable tool for developing a stratified random study design for monitoring the fishery using snorkel surveys. The 1996/1997 flooding on the river has substantially altered the habitat. Habitat mapping of the river is needed in 1997 to maintain the integrity of the study designs for both the snorkel and sculpin surveys.
The prespill fishery of the upper Sacramento River was characterized by using historic Department electrofishing data from 1980 and 1981, angler survey data from 1978-1986, and analysis of fish kill data following the spill. Fish kill estimates were developed by Dr. David Hankin at Humboldt State University using data collected in a systematic manner following the spill. Dr. Hankin also analyzed scale samples from trout carcasses and confirmed the Department's historic observations that most of the trout in the river were wild. Further analysis of scale samples verified that few hatchery trout survive in the river beyond the first season they are stocked. In addition, Dr. Jennifer Nielsen of Hopkins Marine Lab analyzed carcass tissue samples and showed the vast majority of the trout killed in the spill were of a different genetic type than hatchery trout. No further carcass analyses are needed.
Dr. Nielsen's genetic analyses also included tissue samples from the recovering fishery in 1993. Those results raised a question that trout recovery in the lower 16 miles of river may be influenced by Shasta Lake. The results also indicated that tributaries such as Soda Creek were sources of recruitment back into the river following the spill. New genetic techniques are being developed rapidly. The CTC awarded a grant in 1996 to Dr. Nielsen to address the Shasta Lake question. Upon recovery, the CTC may wish to fund further genetic work to characterize baseline conditions of the wild trout fishery to define genetic changes between the prespill fishery and the recovering fishery, and to better define wild trout genetics in the upper Sacramento River for management purposes.
The upper Sacramento trout fishery has been evaluated with a three phase monitoring program since the spill. All phases have provided critical and different types of data that compliment each other. These data have been used to evaluate recovery and restoration needs, but most of all, this information has provided the Department and the California Fish and Game Commission the tools to make informed decisions regarding management of the fishery through the recovery.
The first phase has employed snorkel surveys conducted by TRPA since 1992. Snorkel surveys have provided a non-intrusive, statistically valid technique to evaluate recovery trends. While the data is not directly comparable to prespill numbers developed from carcass data, the recovery trends for the population and broad size classes of trout are readily apparent. These surveys have also provided data on the recovery of various non-game fish species. The CTC awarded a 1996 grant to TRPA to continue these surveys through 1998. New angling regulations will be discussed and potentially adopted by the Fish and Game Commission in the Fall of 1997. These new regulations will be in place on the river in 1998 and 1999. Extending funding for snorkel surveys through 1999 would be valuable to evaluate differing angling regulations and different hatchery stocking regimes on the wild trout fishery and its recovery. Depending on the results of the 1998 and 1999 surveys further surveys may be necessary to establish baseline population levels for fish species using this easily repeatable technique.
The second phase of the trout recovery monitoring program has used electrofishing surveys conducted by the Department since 1993. Electrofishing surveys have allowed the Department to look at population structure. Recovery of the fishery is not only dependant on the total numbers of fish, but the size and age class distribution. Electrofishing has been used to evaluate size class distribution, age class distribution, average size, condition, growth, geographic distribution of hatchery trout after the fishing season, and effects of angling regulations on the fishery. These surveys were initiated in 1993 to insure that the wild trout population levels had recovered to a point where limited mortality associated with collection of fish would not affect recovery of the fishery. Historic information exists from 1980 and 1981. Indications from the snorkel and electrofishing surveys are that trout numbers are continuing to increase, 1992 and 1993 year classes are not present in large numbers, 1996 reproduction is substantially lower than 1994 and 1995, and the size class distribution and age structure is still readjusting from the effects of the spill. In addition, growth rate analyses indicated that wild trout had a reduced growth rate in 1994 when compared to 1979 data. Lower growth rates in 1994 may be associated with a limited food base following the spill. Funding the electrofishing surveys for at least 1997 and 1998 and possibly 1999 is important for establishing angling regulations for management of the river, establishing baseline data, and evaluating recovery of the fishery. The CTC may also consider funding 1996 scale analyses to evaluate growth rates as an indication of recovery of the food base. Population modeling might also be valuable to determine the effects of missing year classes, and angling on recovery of the trout population.
The third phase of the trout recovery monitoring program has included
angler surveys by the Department since the river reopened to angling in
1994. These surveys have provided key information regarding angler pressure,
catch rates, harvest rates, and the effects of harvest on the recovering
fishery. These data have also been compared with angler surveys conducted
prior to the spill as an indication of recovery of the fishery. Angler
surveys coupled with electrofishing surveys have shown that: good quality
angling opportunities exist on the river under the current management scheme;
harvest on the river has substantially decreased the average size of wild
trout in the areas where harvest is allowed; hatchery trout do not survive
in substantial numbers to be important to the fishery one year after stocking;
and wild trout harvest declines rapidly after the fishing season begins,
indicating either over harvest or displacement of wild trout. Funding for
angler surveys in 1997 will provide essential information for setting angling
regulations for management of the river both now and in the future. Because
the trout angling regulations that will be adopted for the 1998 and 1999
fishing seasons are likely to be more long-term, funding of angler surveys
in 1998 and possibly 1999 are advisable. 1998 and 1999 surveys will provide
baseline data under the long-term management scheme, and will allow the
evaluation of the effects of the new management scheme on angling quality
and the fishery.
POTENTIAL MECHANISMS FOR IMPLEMENTATION
|1.||CTC Contract The CTC has the option of developing a request for proposals to be advertised for a contract to an outside party.|
|2.||CTC Grant The CTC can outline the needs of the CTC in future grant packages.|
|3.||Utilize Existing Department Staff Certain studies have been conducted by Cantara Staff and the CTC could choose to continue funding those projects.|
RECOMMENDED ACTIONS FOR IMPLEMENTATION
The following study and research projects are high priorities for CTC consideration because they will provide critical information to manage the recovering fishery resources, will guide further restoration activities on the upper Sacramento River, will document recovery, and will establish baseline conditions in the event of future accidents both on the river and elsewhere.
1. Snorkel Surveys are funded by a CTC Grant through 1998. One additional year of funding, in 1999, would provide two years of data under the 1998-99 angling regulations. If the management scheme is changed, this additional funding would be valuable to evaluate potentially different angling regulations and different hatchery stocking regimes on the wild trout fishery and its recovery. Depending on the results of the 1998 and 1999 surveys, further surveys may be necessary to establish baseline population levels for fish species using this easily repeatable technique. (Grants for 1996 and 1997 surveys approved March 14, 1996.)
2. Electrofishing Surveys should be funded in at least 1997 and 1998, and possibly 1999. These surveys will aid in development and evaluation of angling regulations for management of the river in 1998 and 1999, will establish baseline data in the event of future spills, and help evaluate the recovery of the fishery.
3. Scale Analyses to determine growth rates of wild trout should be funded to aid in developing angling regulations for 1998-99 and to evaluate growth rates as an indication of recovery of the food base. Scales were collected in 1996. The last evaluation (in 1994) indicated that wild trout growth rates following the spill were less than prespill growth rates from 1979.
4. Angler Surveys are funded by a CTC Grant for 1997 and should be considered for funding in 1998 and 1999. These surveys provide essential information for setting angling regulations for management of the river both presently and in the future. The 1998 and 1999 surveys would provide baseline data under the long-term management scheme that could be used in future economic evaluations. In addition, the surveys would allow the evaluation of the effects of the new management scheme on angling quality and the fishery. Angler Surveys would also continue the presence of uniformed staff on the river and facilitate one-on-one contact with the resource users. (Grant for 1997 surveys approved January 24, 1997.)
5. Mollusc Surveys might be valuable, at most, every other year to track recovery.
6. Crayfish Recovery Surveys might be valuable in at least the last year of the CTC program to establish baseline population levels and recovery times for this species.
7. Wild Trout Genetic Evaluations might be valuable in the last year of the CTC program to characterize baseline conditions of the wild trout fishery in the event of future spills, to define changes genetically between the prespill fishery and the recovering fishery, and to better define wild trout genetics in the upper Sacramento River for management purposes.
8. Riffle Sculpin Surveys might be valuable by the CTC in at
least the last year of its program if 1997 surveys indicate the population
is still increasing. This study will establish baseline population levels
and recovery times for this species.
TABLE 1. Yearly cost estimate breakdown to CTC if recommended
study and research projects are funded.
|Growth Rate Evaluation||$10,000||$0||$0||$0|
|Riffle Sculpin Survey||$0||$0||$0||$50,000|
Grand Total of Recommended Study and Research Projects
*If angling regulations are not changed in 1998 and 1999, then angler
surveys would not be necessary and the Grand Total would = $500,000.