Download Sacramento Perch Stocking Report

Attachment 9 Sacramento Perch Stocking Report Introduction The Sacramento perch (SP) is a native sunfish that once was abundant, but is now extirpated from virtually all of its former habitats throughout the Sacramento‐San Joaquin watershed (Tharratt and McKechnie 1966, Aceituno and Nicola 1976, Leidy 1984, Gobalet and Jones 1995, Moyle 2002). SP have been listed as a species targeted for recovery in the Delta Native Fishes Recovery Plan (Moyle et al. 1996), are listed by the Department of Fish and Game as a Species of Special concern (Moyle et al. 1995), and are classified by CALFED as an At‐Risk (Priority Group 2) Species in the 2001 ERP (Goal 1, objective 2, pp.140). Our initial project (ERP 02‐P34) to study the basic biology of SP was listed as Milestone 117 by the CBDA (2004). SP would undoubtedly be listed as an endangered species if there were not populations established outside its native range. Previously it was thought that populations in Clear Lake and in the Alameda Creek drainage were persisting, if tenuously. However we failed to catch SP in our sampling of Clear Lake and Calaveras Reservoir on Alameda Creek, indicating that these populations have likely been extirpated. The introduced SP populations in the upper Klamath watershed, in Pyramid Lake, Nevada, in the lower Walker River, and in the Owens River are probably secure in the short term because of their abundance and fairly broad distribution within these waters. However, natural extirpation of most populations established outside the SP’s native range suggests that long‐term persistence in these areas may be a problem (P. Crain, unpublished data). Extirpations of introduced populations are usually the result of changing conditions in managed waters, but precise causes are often not known. According to CBDA (2004): “There is thus a need to establish populations in places within their native range that can be closely monitored to be sure this species persists in the future. The reintroduction of SP into selected habitats in the Central Valley is closely linked to restoration of non‐tidal perennial aquatic habitats, Delta sloughs, and elimination of inter‐specific competitor or predator species.” How farm ponds can contribute to restoration of Sacramento perch Ponds can be used to raise large numbers of SP, which can then be directly or passively introduced into Delta and other waterways. This could be accomplished by draining ponds into a slough or ditch, or by allowing flood waters to carry SP into the Delta. . The constant vectoring of SP into the Delta may create self sustaining populations and/or a fishery for them. We envision this program becoming a key part of recovery efforts for Sacramento perch (thereby helping to prevent listing as a threatened species) by two means: (1) increased popularity of SP as a farm pond fish results in increased numbers of ‘escapees’ in other habitats and (2) in some areas high densities of SP escapees may allow for development of wild, self‐sustaining populations. However, our basic model is a source‐sink model, where SP produced in ponds (1) survive and grow to large size in outside environments, (2) do not reproduce successfully (because of competition and predation from alien species), and (3) contribute to the sport fishery as a native ‘pan fish.’ If ponds in this study demonstrate potential for restoring Sacramento perch populations, it may be possible to develop ponds and other habitats on public lands that are managed solely for the purpose of reintroducing Sacramento perch into the wild. Choice of ponds for stocking Criteria for selecting ponds was developed in conjunction with Yolo and Solano County RCD’s and each pond or pond site was visited and consultation was made with the land owner on site. In the development of the criteria 3 conceptual models were used as guidelines: 1. The role of farm ponds in agro‐ecosystems Tail water ponds provide benefits to farmers by capturing topsoil that is lost during irrigation and winter rains. Ponds also provide a way of increasing groundwater infiltration. The capture of runoff as groundwater and surface water helps in the conservation and reuse of water especially during drought periods. By lessening the amount of soil lost during farming practices tail water ponds decrease the need to replace soil, or to add chemical and mineral additives. Tailwater and seasonal ponds can provide open water and edge vegetation typically dominated by tules, sedges, smartweed, and similar endemic species. Vegetated areas can support a variety of wildlife and fish species. The cover provided on the margin of ponds can support upland mammals, such as mice, raccoons, hares, and cottontails, as well as several amphibians and reptiles species, including giant garter snakes and, potentially, red‐
legged frogs. If such ponds are large enough, they can also support larger aquatic mammals, such as otters, muskrats, and beavers. The open water and edge vegetation can support a diversity of birds including grebes, ibis, egrets and other shorebirds and wading birds. If designed properly, the open water and adjacent freshwater marsh vegetation can provide brood pond habitat for resident waterfowl. Lastly, the presence of relatively undisturbed marsh vegetation adjacent to shallow water could provide important refugia and rearing habitat for Sacramento perch. 2. How farm ponds can contribute to restoration of Sacramento perch Ponds can be used to raise large numbers of SP, which can then be directly or passively introduced into Delta and other waterways. This could be accomplished by draining ponds into a slough or ditch, or by allowing flood waters to carry SP into the Delta. . The constant vectoring of SP into the Delta may create self sustaining populations and/or a fishery for them. We envision this program becoming a key part of recovery efforts for Sacramento perch (thereby helping to prevent listing as a threatened species) by two means: (1) increased popularity of SP as a farm pond fish results in increased numbers of ‘escapees’ in other habitats and (2) in some areas high densities of SP escapees may allow for development of wild, self‐sustaining populations. However, our basic model is a source‐sink model, where SP produced in ponds (1) survive and grow to large size in outside environments, (2) do not reproduce successfully (because of competition and predation from alien species), and (3) contribute to the sport fishery as a native ‘pan fish.’ If ponds in this study demonstrate potential for restoring Sacramento perch populations, it may be possible to develop ponds and other habitats on public lands that are managed solely for the purpose of reintroducing Sacramento perch into the wild. 3. Roles of cooperators in restoration of Sacramento perch This project depends on cooperation among private landowners, NGOs, local and state agencies, and university researchers. The ‘players’ listed below have all enthusiastically agreed to become part of this cooperative effort, coordinated by Audubon California. This will require 2‐3 meetings per year by participants, including visits to pilot project sites. Coordination will be done electronically through e‐mail and postings on a website (YCRCD & Audubon LSP). UCD will provide expertise in designing SP friendly ponds and will oversee the planting of SP into the ponds. UCD will also do all of the fish monitoring activities involved in this project. Landowners will provide space for ponds and be responsible for maintenance, working closely with the RCD and others. Their satisfaction with the results of this work, will ultimately determine its long‐term success, including spread to other farms. Audubon California & Yolo County Resource Conservation District will develop contacts with landowners and provide help with permitting and other processes and will provide expertise and funding for the construction of ponds through the Yolo‐Solano Conservation Partnership. Contra Costa Vector Control Agency, through biologist Chris Miller, will provide larval and juvenile Sacramento perch for stocking. Mr. Miller currently rears Sacramento perch for use in mosquito control operations in Contra Costa County and is willing to expand his operation to provide additional fish for this project. The California Department of Fish and Game, will work closely with UCD and others to advise sampling, pond construction, and stocking of perch. Criteria The following criteria were chosen to evaluate pond sites for restoration and or building and were given a plus or a minus in the evaluation resulting in a overall score that reflected a value of 1 for a plus and a 0 for a minus, ie. a pond with with 5 plus scores would get a rating of 5 as the minus scores do not detract from the overall plus scores; 1. Does the pond or building site and the landowner meet the overall criteria for the project? 2. Does the owner overall show interest have cooperative attitude while being interviewed. 3. Is the existing pond or area where a pond can be built having sufficient size to meet criteria for pond size and depth. 4. If an existing pond does it meet depth criteria or can the depth be lowered to the desired depth for Sacramento perch. 5. Is there aquatic vegetation in the existing pond and what condition is it in if there is existing aquatic vegetation. 6. Are the proper depths and slopes available in an existing pond for spawning and foraging? 7. What is the status and condition of upland vegetation if an existing pond? 8. How much excavation and compaction is required to build a pond project on the site. 9. From soils reports and water table depth what is the likelihood that proper water depths will be maintained in the pond. 10. If water will be needed to maintain proper pond depth is there a reliable source of water that is accessible. 11. Is there access from the spillway or overflow of the pond to an adjacent waterway with eventual connection to the Delta? 12. What is the potential of the pond and pond site for further education of school children and other land owners? 13. If an existing pond is there good access for sampling i.e. is there access for a boat or vehicle? Twenty four ponds were surveyed with 13 involving existing pond structures and 11 being proposed new ponds. A spreadsheet with scores is presented in Appendix A. Stocking,Goals and Methods for sampling ponds In the Goals and Methods the following was outlined as a deliverable: Goal#1 Develop strategies for using farm ponds and other agricultural waterways to recover Sacramento perch as a resident of Central Valley waters. Task 1. Establish and monitor perch populations in existing ponds and sloughs to determine potential for using established areas. We plan to plant SP in several ponds as a restoration strategy to reintroduce SP back into the Delta. Successive plantings will be monitored for growth and relative numbers to determine if this is a strategy that is feasible for reintroduction of SP into Delta Habitats. Environmental variables and fish communities will also be monitored to determine the relative impact of different environmental conditions and interspecific competition has on SP long term survival. Stocking Ponds Sacramento perch juveniles were purchased from Namakan West Fisheries of 27352 Fahey Rd, Gustine, California. Using a truck and trailer with a 550 gallon tank with oxygen Sacramento perch juveniles were transported from Gustine to various pond locations throughout Yolo and Solano County. Juvenile Sacramento perch were stocked in general with 500 or more juveniles per pond, one smaller pond was stocked with 300 juveniles in the first stocking, subsequently some ponds were restocked with juveniles and larvae as a supplement to the original stocking. Numbers of fish stocked are listed in table 1. Table 1. Table depicting dates, stocking numbers, average number of perch caught, last sampling date, number of sampling events and estimates of pond perch populations. In the stocking column any number over one thousand denotes stocking of larvae, a number in the hundreds denoted juvenile perch, and a number in the tens denotes adults. Date planted Batcheller 8/12/08 Chapple 7/17/08 # perch planted 500 390 Avg number of perch caught 4 8 End sample date 10/10 10/10 # samp
le trips 6 6 Pond Pop. Extirpated Extirpated Defty 8/12/08 10/1/08 5/25/09 Haag 7/17/08 6/1/09 Hasbrook 8/27/08 Power 4/28/11 Sperandio 10/1/08 Beaver 5/17/08 Fong 6/1/07 12/5/08 297 400 *10,000 570 *15,000 500 26 300 150 10,000 *24 2 11/09 5 33 .7 N/A 2 15 48 ongoing 8 1000+ 10/10 ongoing 10/09 ongoing ongoing Extirpated 150 Extirpated <100 1000+ 6 2 2 8 7 Extirpated Methods Fish Sampling Sacramento perch were sampled using one primary method and two other secondary methods to verify the primary method wasn’t missing and fish species and larger Sacramento perch. The primary method used was a clover leaf trap that was 24”X24”X11.5” (Figure 1), secondarily a 30’X4’X 3/8” stretch beach seine was used intermittently, and finally a 50’X4’X1.5” stretch gill net was tried once and not used again. Figure 1 Clover leaf trap used as primary method of sampling Sacramento perch in farm ponds. Ponds were sampled an average of 2 to 4 times per year while it was determined that sampling was productive, in some ponds Sacramento perch were extirpated and sampling was discontinued (Table 1). Water Quality Monitoring Water quality was monitored in two major ways. Temperature was monitored using Onset ©Hobo Pro v2 water temperature data loggers. Dissolved oxygen, conductivity, and spot temperatures were measured with a YSI 85 multi‐parameter hand held water quality meter. Age and Growth Sacramento perch from three ponds (Defty, Fong, Haag) were sacrificed to extract otoliths which were used for daily age at length analysis. Data Sheet A full data sheet that was used for sampling farm ponds is attached in appendix 2. Results Catch A total of 9 ponds were stocked and followed through the entirety of the study. Populations that became extirpated for various reasons were followed until it was determined that no Sacramento perch remained. Table 1 depicts the number of times each pond was sampled and the average catch per sampling session. Water Quality Monitoring Water temperature was monitored on an average temperature per hour, temperature graphs are depicted below. Average Temperature by Month Sacramento Perch Ponds
Degrees Celsius
30.0
25.0
20.0
15.0
10.0
5.0
0.0
Chapple
Defty
Fong
Haag
Hasbrook
Sperandio
Figure 2. Sacramento perch ponds average monthly temperatures. Not all ponds represented due to failure of temperature Hobos and the loss of some temperature Hobos. Juvenile Growth Juvenile growth was determined from daily otolith growth rings. Three ponds were analyzed: Defty, Fong, and the Hagg pond. The Defty pond Sacramento perch were killed by a low DO event, so were salvaged for growth analysis. Both the Fong and Hagg ponds fish were analyzed because of abundant populations and they were considered the most successful ponds in the project. Growth analysis is presented in three different growth curve graphs below. Average Growth of Juvenile Sacramento Perch (mm/day) in the Defty Pond
100
mm
80
60
40
avg
20
SD+
0
SD‐
0
10 20 30 40 50 60 70 80 90 100 110 120
Days
Aveerage Growth of Juvenile Sacramento Perch (mm/day) in the Fong Pond
150
mm
100
avg
50
SD+
SD‐
0
0
50
100
150
200
Days
70
60
50
40
30
20
10
0
avg
SD+
SD‐
1
10
19
28
37
46
55
64
73
82
91
100
109
118
127
136
145
154
163
172
181
190
199
mm
Average Growth of Juvenile Sacramento perch (mm/day) in the Haag Pond
Days
Figures 3,4,and 5. Average growth of juvenile Sacramento perch in mm/day. Other ponds not represented because not enough perch survived for this type of analysis. Discussion Factors that impact Sacramento perch restoration in farm ponds and adjacent wetlands Sacramento perch were once one of the most abundant native fishes within the Central Valley aquatic ecosystem. Today for intents and purposes they are extirpated from all habitats within the Central Valley. The idea of using farm ponds for passive restoration through the use of farm ponds came from the many non‐native farm pond fishes that are found in streams that are adjacent or on streams throughout California. For example: Two ponds on the UC Davis campus have contained Sacramento perch at various times and have drains that flow into Putah Creek. Periodically Sacramento perch are captured within Putah Creek below these drains in an annual monitoring program. Although, the perch are not abundant it was hypothesized that with enough source ponds vectoring perch into waterways there would a least be a remnant population in specified areas that can support perch. Factors that have an impact on Sacramento perch in ponds and wetlands are bulleted in order of descending importance. 1. Sacramento perch do not coexist with other non‐native fishes, especially sunfishes. An exception to this seems to be largemouth bass after perch have become established within a system. There are several examples of this, but the most prominent is their coexistence with largemouth bass in the three basins of Abbott’s Lagoon in Point Reyes National Seashore. In this project perch were extirpated within two years after the introduction of bluegill and within one year when comingled with green sunfish. 2. Sacramento perch unlike other centrarchid fishes do not tolerate warm temperatures except at the larval and small juvenile stages. Adult Sacramento perch will disappear from waters that 3.
4.
5.
6.
stay above 22 degrees Celsius for extended periods of time. Sacramento perch will show lowered growth rates in waters that are too warm for their physiology. Sacramento perch need shallow flooded vegetation, either annual or aquatic for spawning substrate, but from previous studies will spawn just about anywhere if abundant. Sacramento perch males do guard the nest until eggs hatch, but unlike many other centrachid fishes do not guard the larvae and can be moved off the nest more easily than other sunfish species. Sacramento perch are not true colonial spawners, but do spawn in loose aggregations when abundant. At Contra Cost Vector Control Sacramento perch post‐larvae and young juveniles have been shown to effectively control mosquitoes. Description of Ponds and Problems Out of 9 ponds in this project only three that really performed to expectations. There were many problems that led to the demise of Sacramento perch in the other ponds, but the causation of their demise was self‐evident in most cases. Batcheller’s pond was and existing pond that was very shallow and had continuous vegetation around its edges (reeds, cattails, and sedges. The pond was deepened in one area , completely drained and all fish eliminated before the project . The source of water was an irrigation sump that was supplied with water from the local irrigation district. It was thought that if the water could be screened as it was pumped in larval fish and other invasive organisms (corbicula clams etc.) would be eliminated from the source water. Problems arose early the filter continually clogged and had to be eventually abandoned in the intial filling of the pond. Because of its wide spatial design and surrounding marsh lands very few Sacramento perch were ever caught during sampling. Green sunfish started showing in the catches soon after the pond was filled, but were removed and placed into the pumping basin adjacent to the pond. During the one year break in the project due to State Budget issues the pond became infested with thousands of green sunfish and black bullheads. After not finding any Sacramento perch within several sampling trips the pond was dropped and the perch were assumed extirpated because of the high catches of green sunfish and black bullhead. The Chapple pond started out as a good pond and capture of perch was about average within the pond group over the fall and first Winter of the project (2008). The pond was supplied with irrigation water from a canal that was adjacent to the pond. The first sign that there were problems was green sunfish starting to show in the catches, but as they were caught they were removed (back into the canal) and catches of perch didn’t diminish through the summer and fall. When I came back late the next spring for the bi‐annual sampling the pond was almost completely drained (<3’ deep), the perch were gone and they had been replaced by green sunfish that had much greater tolerance to warm temperatures. The Defty pond was a real great pond with proper depth and good temperatures for perch growth. The ponds water level was essentially controlled by groundwater, but the levels seemed to stay high enough through the first year of the project. In the beginning of the irrigation season in 2009 (summer) the farm next door irrigated its alfalfa field and the run‐off that filled the pond plunged the pond into hypoxia killing most of the fish in the pond. I walked the pond and estimated that over 700 Sacramento perch had been asphyxiated. Subsequently later that year in the fall the water table fell below the pond and it dried up ending its participation in the project. Fongs pond was started before the initiation of the project but was included because of a longer sampling record and the knowledge that Sacramento perch were well established within it. The water supply for the pond was mostly ground water but was supplemented with well water when needed.Catches ranged from 3 to over 100 in 10 traps. All the perch caught were smallish (up to 160mm) and it was thought the the shallow nature of the pond high temperatures during summer months, plus the high abundance of perch were working together to create this problem. Sacramento blackfish were added to provide forage fish, but because the perch were so small the blackfish soon outgrew the perch’s gape size and were not able to be foraged. Largemouth bass were added towards the end of the project so the status of perch size has not been investigated with an added predator to the pond. Hagg pond was one of the first ponds constructed and was designed for Sacramento perch with a large deep section bordering on a less steep end that was designed for spawning and foraging. The initial stocking of the pond was done with little time elapsing from the end of its first fill up. There was also some loss of juvenile perch due to lack of acclimation when the stocking was first done. In the fall and winter after the first stocking no Sacramento perch were caught and it was thought that the stocking had been a failure. When Sacramento perch larvae became available in the late spring the pond was again restocked to compensated for what was believed to be the failure of the first stocking. In subsequent samplings after the larvae stocking larger perch (1+) in size were caught along with young‐
of‐the‐year (YOY) and the initial stocking was discovered to have been a success. The Haag pond has been one of the most consistent producers of Sacramento perch which s attributable to its proper design, the owners cooperation in keeping the water levels full, and the lack of non‐native competitors. Hasbrook’s pond was initially thought to be one of the most promising ponds in that the water quality was good and that during wet seasons the pond was overtopped by flows from Putah Creek thus creating a vector into a local water system that has a good connection to the Delta. Problems started with the reconstruction of this pond as the pond was not completely drained before it was refilled. Before construction sampling had revealed that the pond contained bluegill and green sunfish, plus black crappie. The contractor was supposed to completely drain the pond and the sunfish were to be rescued and returned to Putah Creek, but this was not completed before the refilling of the pond. In initial samplings of this pond many non‐native sunfish were captured, but few Sacramento perch. The non‐native sunfish were removed when caught, but it was a battle that was eventually lost and the perch were extirpated. The Power pond was stocked after the end of the sampling for this project and has not been checked yet to see how the population of Sacramento perch are doing. But given the design of the pond and the clean source of water with no non‐native fish in the source it is thought that this pond will do well like the other ponds that have similar circumstances. Sperandio was a last minute decision to stock because of and excess of juvenile perch left from other initial stockings. The pond dried up to a small area ((10x20) that was deepened in a very short time and never held water even during the winter and spring. Initially a few perch were caught, but were in poor condition looking thin and emaciated. The pond was abandoned when it was determined that it would never hold water and the Sacramento perch became extirpated. Ponds on the UC Davis campus were restocked with about 1500 excess perch that were left over from the stocking of the other ponds. Initial sampling results show them in good health, but they are small. The campus ponds contain only one other fish the three spined stickleback which are compatible with Sacramento perch. The ponds will be continued to be monitored by students from the Wildlife, Fish and Conservation Biology Department in the future. The only problem with the campus ponds seems to be that they are somewhat shallow and tend to heat up during July and August like the other ponds only a bit hotter, but not to the point of being lethal. Recommendations for perch ponds 1. Sacramento perch ponds should be large enough to encompass a range of depths that allow cool water in deep areas during summer and shallow areas for spawning and foraging. 2. A suggested maximum depth for deep areas is > 12 feet and preferably 15‐20 feet. 3. Perch ponds should have their own source of water that is distinct from local waters and irrigation district waters. 4. Shade is a important component providing cooler areas and cover from overhead predators. 5. Perch should be raised alone until they have become established and then a predator like largemouth bass can be added. In Abbott’s Lagoon Sacramento perch use deeper offshore habitats while bass use inshore habitats. 6. Other native fishes such as Sacramento blackfish, hitch , and tule perch are compatible fish to raise with Sacramento perch. 7. Avoid having too much shallow area in the pond as it will quickly fill in with cattail, perch need shallow areas mainly in the spring for spawning, but will mainly reside in deeper areas of the pond most of the year. 8. Perch ponds should be drainable in case non‐native sunfishes invade the pond. This allows the pond to be cleaned of these fishes and the perch can start over. 9. Perch ponds should have access by a spillway or stand pipe to local waterways so as to be a vector of perch into the greater landscape.