Endangered Lost River (
Contrary to previous studies, this study did not capture any Lost River suckers in the Clear Lake tributaries. Genetics samples from suckers collected during this study were used to verify that no Lost River suckers were captured. At the time of this study, genetics could not identify the differences between shortnose and the non-endangered Klamath largescale suckers (
We captured suckers, age-0 to age-9, in the Clear Lake tributaries within stream pools and flooded meadows behind water retention structures. However, no suckers were collected in small reservoirs sampled upstream of Clear Lake. Suckers were found in habitats with mud and fine substrate at depths of 0.5–3.0 meters, with most captured at 1.0 meter or less. Suckers co-occurred with nonnative species, which were more abundant in our survey than in previous surveys in the tributaries to Clear Lake.
Gerber Reservoir tributaries yielded more suckers per unit effort than Clear Lake tributaries. All suckers captured in the tributaries of Gerber Reservoir were identified as Klamath Largescale suckers. The suckers in tributaries to Gerber Reservoir were collected in similar habitat as those in Clear Lake tributaries and were age-0 to age-6.
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Multiply | By | To obtain |
Length | ||
---|---|---|
inch (in.) | 2.54 | centimeter (cm) |
Multiply | By | To obtain |
Length | ||
---|---|---|
centimeter (cm) | 0.3937 | inch (in.) |
millimeter (mm) | 0.03937 | inch (in.) |
meter (m) | 3.281 | foot (ft) |
kilometer (km) | 0.6214 | mile (mi) |
Area | ||
square meter (m2) | 10.76 | square foot (ft2) |
square kilometer (km2) | 0.004047 | acre |
Volume | ||
cubic meter (m3) | 1,233 | acre-foot (acre-ft) |
liter (L) | 33.81402 | ounce, fluid (fl. oz) |
Mass | ||
milligram (mg) | 0.00003527 | ounce, avoirdupois (oz) |
Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as:
°F = (1.8 × °C) + 32.
Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).
Vertical coordinate information is referenced to the Bureau of Reclamation Vertical Datum.
Elevation, as used in this report, refers to distance above the vertical datum.
Specific conductance is given in microsiemens per centimeter at 25 degrees Celsius (µS/cm at 25 °C).
Concentrations of chemical constituents in water are given in milligrams per liter (mg/L).
Lost River (
Two recovery units in the Klamath Basin, Oregon. Green shaded areas represent the U.S. Forest Service’s Fremont-Winema National Forest in Oregon and the Modoc National Forest, California.
Figure 1. Overview map showing two recovery units in the Klamath Basin, Oregon
Lost River and shortnose suckers are long-lived catostomids that primarily occupy lakes during the summer months and make spawning migrations into lotic habitats in the spring, beginning at about age-4 to age-7 (
Information on the distribution of suckers within these reaches and timing of habitat use by life stage is limited to several previous survey efforts in the Clear Lake drainage within the Modoc National Forest during the summers of 1972, 1975, and 1989–90 (
The main objective for the 2018 fish survey in Clear Lake and Gerber Reservoir drainages was to update distributional and age structure information of the two endangered suckers. Habitat characteristics associated with the presence of suckers, including basic water-quality conditions were also described. Furthermore, species assemblages in the tributaries of Clear Lake were documented for comparison with information collected in previous surveys.
Clear Lake, located in Modoc County, California, is primarily fed by waters that flow through the U.S. Forest Service’s Modoc National Forest. Willow Creek is the main tributary to Clear Lake and enters near the dam at the lake’s outlet. Prior to the construction of the dam, Mowitz Creek appears to have been the primary tributary because Willow Creek entered the Lost River downstream of the historical lake (
The headwaters of North Fork Willow Creek are located in the U.S. Forest Service’s Fremont-Winema National Forest, Oregon. At the headwaters, the creek passes through privately and publicly owned pasture lands and then enters an area containing large lava rockslides. North Fork Willow Creek descends rapidly in the area containing the lava rockslides, which form steep rapids during the wet season (approximately February–April). During the dry season in which our sampling took place, water flows completely sub-surface through these slides. Downstream of these slides, North Fork Willow Creek flows through several narrow canyons that are separated by large man-made meadows. At the downstream end of the meadows, dams are seasonally closed in order to pool water and create forage for livestock. From the headwaters to the mouth of Clear Lake, the combination of North Fork Willow Creek and Willow Creek flows 34.6 kilometers (km) and loses 284 meters (m) of elevation. Four Mile creek is a major tributary of North Fork Willow Creek. The headwaters of Four Mile Creek are in Four Mile Reservoir, a small impoundment that is primarily fed by snow melt (
Sampling sites where suckers were captured/not captured in the Clear Lake drainage, California, 2018.
Figure 2. Overview map showing sampling sites where suckers were captured/not captured in the Clear Lake drainage, California, 2018
The Boles Creek watershed is in the Modoc National Forest, California. Fletcher Creek is the largest tributary to Boles Creek, surrounded by dense Ponderosa pine at its headwaters, whereas the lower elevations are surrounded by meadows. Fletcher Creek has several smaller tributaries (many of which are unnamed). Two of the larger tributaries are Little Willow Creek and Mosquito Creek (
Mowitz Creek is a low gradient stream consisting of small pools disconnected during summer low flows (
Gerber Reservoir is located in Klamath County, Oregon and is primarily fed by Barnes Valley Creek from the southeast, Ben Hall Creek from the northwest, and Barnes Creek from the northeast (
Sampled sections and where suckers were captured in the Gerber Reservoir drainage, Oregon, August 2018. Insets A–C within this figure show expanded views.
Figure 3. Map of sampled sections and where suckers were captured in the Gerber Reservoir drainage, Oregon, August 2018
Clear Lake tributaries were surveyed for one week during each month from June through September 2018. A total of 47 sites were visited during this period (
Table 1. Site names and sampling locations in the Clear Lake drainage, California, 2018
[Coordinates given are the starting location for the sample site. Unless otherwise indicated, a single pool was sampled at each site.
Waterbody | Site | Latitude | Longitude | Elevation (m) |
North Fork Willow Creek and tributaries | ||||
---|---|---|---|---|
Unnamed N.F. Willow Creek Tributary | UN01 | 41°59'29.0" N | 120°46'31.1" W | 1,657 |
Unnamed N.F. Willow Creek Tributary | UN02 | 41°59'30.5" N | 120°46'34.5" W | 1,654 |
N.F. Willow Creek | LVD01 | 41°59'47.0" N | 120°48'00.2" W | 1,608 |
N.F. Willow Creek | LVD03 | 41°59'42.8" N | 120°48'08.8" W | 1,616 |
N.F. Willow Creek | LVD04 | 41°59'45.8" N | 120°48'13.2" W | 1,604 |
N.F. Willow Creek | LVD06 | 41°59'46.4" N | 120°48'22.0" W | 1,611 |
N.F. Willow Creek | 1W03 | 41°59'30.5" N | 120°48'39.9" W | 1,599 |
N.F. Willow Creek | W06 | 41°59'28.4" N | 120°48'40.1" W | 1,595 |
N.F. Willow Creek | W10 | 41°59'20.3" N | 120°48'34.9" W | 1,608 |
N.F. Willow Creek | W13 | 41°58'57.8" N | 120°48'56.9" W | 1,584 |
N.F. Willow Creek | W18 | 41ᵒ58’20.4" N | 120ᵒ48’35.7" W | 1,568 |
N.F. Willow Creek | 1W19 | 41°57'28.2" N | 120°49'57.6" W | 1,554 |
N.F. Willow Creek | 1W22 | 41°57'26.3" N | 120°50'05.9" W | 1,549 |
N.F. Willow Creek | W24 | 41°57'25.2" N | 120°50'17.3" W | 1,553 |
Weed Valley Reservoir | WVR | 41°57'29.5" N | 120°49'56.8" W | 1,548 |
N.F. Willow Creek | 1W31 | 41°55'03.1" N | 120°52'46.3" W | 1,466 |
Wild Horse Creek | WH04 | 41°58'57.0" N | 120°51'21.6" W | 1,598 |
North Four Mile Reservoir | N4MR | 41°58'28.7" N | 120°54'36.2" W | 1,541 |
Four Mile Reservoir | 14MR | 41°57'09.7" N | 120°53'13.9" W | 1,492 |
South Four Mile Reservoir | S4MR | 41°56'50.3" N | 120°53'01.8" W | 1,492 |
Four Mile Creek | 4M1 | 41°57'02.7" N | 120°53'10.4" W | 1,494 |
Four Mile Creek | 4M2 | 41°57'00.7" N | 120°53'08.4" W | 1,493 |
Four Mile Creek | 4M3 | 41°56'58.5" N | 120°53'06.1" W | 1,492 |
Willow Creek | ||||
Willow Creek | 1W59 | 41°54'00.4" N | 121°02'41.9" W | 1,373 |
Fletcher Creek and tributaries | ||||
Fletcher Creek | B39 | 41°52'29.2" N | 120°36'37.9" W | 1,565 |
Fletcher Creek | B03 | 41°51'16.8" N | 120°39'35.3" W | 1,539 |
Fletcher Creek | B08 | 41°51'26.3" N | 120°42'23.0" W | 1,520 |
Fletcher Creek | B12 | 41°49'13.8" N | 120°45'48.3" W | 1,499 |
Avanzino Reservoir | AR | 41°56'45.7" N | 120°47'43.4" W | 1622 |
Grassy Ravine | GR01 | 41°53'02.7" N | 120°39'35.6" W | 1,562 |
Little Willow Creek | LW01 | 41°54'12.7" N | 120°43'22.4" W | 1,625 |
Little Willow Creek | 1LW02 | 41°52'50.3" N | 120°44'46.3" W | 1,541 |
Mosquito Creek | MC02 | 41°52'49.7" N | 120°45'36.1" W | 1,559 |
Janes Reservoir | JR | 41°52'50.4" N | 120°45'50.2" W | 1,556 |
Deer Hill Reservoir | DHR | 41°49'37.8" N | 120°41'56.3" W | 1,521 |
Tributary to Fletcher | B38 | 41°48'29.1" N | 120°44'33.8" W | 1,509 |
Bayley Reservoir | B41 | 41°48'05.6" N | 120°43'58.6" W | 1,516 |
Telephone Flat Reservoir | TF | 41°46'47.9" N | 120°40'49.0" W | 1,526 |
Boles Creek and tributaries | ||||
Boles Meadow | BM | 41°43'55.9" N | 120°54'23.4" W | 1,494 |
Boles Creek | B19 | 41°44’45.8" N | 120°54'41.3" W | 1,488 |
Boles Creek | 1B20/21 | 41°44'42.2" N | 120°54'58.1" W | 1,489 |
Boles Creek | B22 | 41°44'50.0" N | 120°55'54.4" W | 1,486 |
Boles Creek | 1B24 | 41°45'52.0" N | 120°56'53.3" W | 1,470 |
Boles Creek | B25 | 41°45’59.4" N | 120°56’53.8" W | 1,463 |
Boles Creek | 1B29 | 41°50'06.9" N | 120°59'43.9" W | 1,419 |
Boles Creek | B30 | 41°50'15.1" N | 120°59'47.7" W | 1,420 |
Mowitz Creek | ||||
Mowitz Creek | MWC01 | 41°49'08.6" N | 121°04'11.3" W | 1,378 |
These sites were sampled twice.
We used a variety of collection equipment to sample the wide range of habitats in the Clear Lake drainage, with limited available effort. Two ground crews went out each sampling event. Sampling methods used to capture suckers included electrofishing, trap nets, and trammel nets. There was no defined area (in square meters) sampled, instead, electrofishing surveys were limited to 15 minutes for each site to maximize number of sites sampled. Stream runs were sampled for close to the 15-minute limit while stream pools were sampled for much less time with duration dependent on the size of the pool. Smith & Root LR-24 electrofisher™ backpacks with an 11-inch stainless-steel ring electrode were used to capture fish. Power settings were initially set to standardize power output. However, because of poor performance at the first sampling site, settings were later altered to meet a desired fish response of lightly stunned. Power output settings on the electrofisher ranged from 38 to 325 watts. These calculations were based on electrofisher volts settings multiplied by the amp output. Duty cycle ranged from 25 to 40 percent. Shocking was done with at least one netter for each site. Total duration of shocking time, in seconds, was recorded after each effort at each site. Trap and trammel nets were set in areas where it was too deep to wade in the stream and therefore too deep to use a backpack electrofisher. Set times for trap nets did not exceed 24 hours and set times for trammel nets did not exceed three hours. Set and pull times were recorded for each net set. The number of nets set was determined in the field based on width, depth, and length of the stream and accessibility to the sites, and did not exceed two nets per sample site. The trap nets used were rectangular with mouth dimensions of 0.61 × 0.91 m, a 10-m-lead, and three internal fykes. Two anchors were tied at each end to prevent the trap from collapsing. Each trap net was set across the current, and if the width of the stream was less than 10 m, the nets were set at an angle. Trammel nets used were 15 m in length, 1.8-m tall with two outer panels (30-centimeter [cm] bar mesh), an inner panel (3.8-cm bar mesh), a foam core float line, and a lead core bottom line. Trammel nets were only used on four occasions during the June sampling event because of their ineffectiveness at capturing juvenile suckers.
We made four single day trips to the Gerber Reservoir drainage from August 20 through 31, 2018. Sampling was conducted at Barnes Valley Creek and two of its tributaries, Lapham Creek and Long Branch Creek. On each date a different section of a creek was sampled for a total of four sampling sections (
Table 2. Site names and sampling locations in the Gerber Reservoir drainage, Oregon, 2018
[Coordinates given are the starting and ending location for the sample sites, denoted by time.
Creek | Site |
Date |
Period | Time |
Latitude | Longitude | Elevation |
Barnes Valley Creek | BVC01 | 08-20-2018 | Start | 09:46 | 42°10'02.9" N | 120°58'13.9" W | 1,567 |
End | 14:13 | 42°10'10.0" N | 120°58'01.4" W | 1,577 | |||
Lapham Creek | LHC01 | 08-31-2018 | Start | 09:25 | 42°11'16.3" N | 120°52'35.6" W | 1,585 |
End | 12:00 | 42°11'16.4" N | 120°52'20.5" W | 1,594 | |||
Long Branch Creek | LBC01 | 08-30-2018 | Start | 09:37 | 42°12'00.1" N | 120°59'56.6" W | 1,573 |
End | 12:01 | 42°12'14.0" N | 120°59'50.0" W | 1,582 | |||
Long Branch Creek | LBC02 | 08-22-2018 | Start | 09:35 | 42°11'21.4" N | 121°00'39.6" W | 1,556 |
End | 12:30 | 42°11'45.8" N | 121°00'23.0" W | 1,569 |
A single ground crew went out each sampling event. Electrofishing was the only sampling method used due to the more continuous nature of the streams in the Gerber Reservoir drainage. A Smith & Root LR-24 electrofisher backpack with an 11-inch stainless-steel ring electrode was used to capture fish. As in Clear Lake Tributaries, wattage settings were altered to meet a desired fish response of lightly stunned. Power output settings on the electrofisher ranged from 84 to 240 watts. These calculations were based on electrofisher volts settings multiplied by the amp output. The duty cycle ranged from 30 to 40 percent. Shocking was done with at least one netter for each site. The duration of effort was recorded in seconds per survey per site. We started surveys at road crossings then worked continuously upstream or downstream, stopping when suckers were encountered. The exact locations of suckers within each reach were documented and habitat characteristics were recorded when suckers were captured. Bycatch was not recorded during these surveys.
The habitat at each site was characterized and described in field notes. In the Clear Lake drainage, where pools were often discontinuous, max pool depth, width, and length were estimated. Bank suitability and height of incised channel were also described in field notes. Signs of grazing and number of livestock were noted. Stream wetted width and max depth were measured at each site. Substrate type, submerged vegetation, and woody debris within sites were characterized based on type and abundance. Submerged vegetation was classified as none, moderate (1–15 percent), and a lot (>20 percent), while number of pieces of woody debris greater than 10 cm in diameter was counted.
Water quality was measured in both the Clear Lake and Gerber Reservoir drainages to understand habitat conditions correlated with sucker detections. Water temperature was monitored, using HOBO® temperature loggers, hourly from mid-June to mid-September at six sites (W03, W31, W59, B12, B24, and B29) in the Clear Lake drainage. The HOBO® loggers were placed throughout the watershed with two in North Fork Willow Creek, one in Willow Creek, two in Boles Creek, and one in Fletcher Creek. Due to receding waters, the three HOBO® loggers, located in the Boles Creek watershed were no longer immersed by the end of the study. The last reading at all six sites occurred July 31, 2018. Five of the six sites where HOBO® loggers were placed (excluding B12) were sites that were visited on two occasions (
To document size, age, and species composition of suckers throughout the Clear Lake and Gerber Reservoir drainages, we measured standard length (SL) of captured suckers and collected several biological samples. To estimate fish age, the leading left pectoral fin ray was removed at the proximal end of suckers measuring 50 millimeters (mm) SL or greater. Using clean scissors, tissue samples for genetics were taken from the upper lobe of the caudal fin from all suckers and then covered with wax paper and placed within coin envelopes for drying.
Passive integrated transponder (PIT) tags were implanted in some suckers to facilitate future monitoring of within stream movements. Suckers were scanned for previously implanted PIT tags using the Biomark® Portable Transceiver System Model 2001F-ISO. Untagged suckers greater than 70 mm SL were injected with a 135 kilohertz 12 mm PIT tag ventrally through the body cavity. To improve sucker post tagging survival, suckers were only administered a PIT tag when water temperatures were less than 20 °C. Recaptures, as determined by the presence of a PIT tag, were recorded and all suckers were photographed. Fish were released at the site of capture.
We summarized the prevalence and intensity of external afflictions on all captured suckers. Emaciation, deformities, macro parasites, petechial skin hemorrhaging, and gill abnormalities were systematically recorded. Other abnormalities and afflictions were noted when they were observed. We paid close attention to those afflictions that are common or potentially associated with mortality (
To identify patterns in cohabitation among fishes and potential competition with or predation of suckers by other fishes, we recorded data on the location, size, and abundance of non-sucker fishes collected during surveys in Clear Lake tributaries. We counted or estimated the number of non-sucker fishes captured during each survey effort. Nontarget fish were estimated when there were too many fish to count in a reasonable amount of time without potentially harming the fish. In these instances, fish were counted from a full aquarium net and then the number of nets were counted. The number of nontarget fish was estimated through extrapolation on these occasions. Standard length was measured for a random selection of five fish of each fish species captured in each survey.
To age the suckers, fin rays were mounted in epoxy, sectioned, and viewed by two experienced readers under magnification using transmitted light (
In the Clear Lake drainage, suckers were identified to species using genetic identification techniques described by
In the Gerber Reservoir drainage, only morphological identifications were conducted. Historically there have not been any Lost River suckers in the Gerber Reservoir drainage, only shortnose and Klamath largescale suckers. Genetics were not used because genetic techniques that were available at the time of this study could not distinguish shortnose suckers from Klamath largescale suckers.
Suckers were not abundant during our survey with only 76 suckers captured during 8 of the 74 (11 percent) sampling events in Clear Lake tributaries (
Table 3. Number of suckers captured by site, date, sampling equipment, and effort in the Clear Lake drainage, California, 2018
[Coordinates for sites are given in
Site name | Date |
Suckers |
Electrofishing |
Trap net |
Trammel net |
North Fork Willow Creek and tributaries | |||||
---|---|---|---|---|---|
UN01 | 06-20-2018 | 0 | 180 | -- | -- |
UN02 | 06-20-2018 | 0 | 244 | -- | -- |
LVD01 | 06-20-2018 | 0 | 511 | -- | -- |
3LVD01 | 07-26-2018 | 1 | -- | 23:32 | -- |
LVD03 | 06-20-2018 | 0 | -- | -- | 01:15 |
LVD04 | 06-20-2018 | 0 | -- | -- | 01:01 |
3LVD04 | 07-26-2018 | 0 | -- | 23:26 | -- |
LVD06 | 06-20-2018 | 0 | 702 | -- | -- |
1,2LVD01-LVD04 | 07-27-2018 | 0 | 823 | -- | -- |
1LVD04-W01 | 07-26-2018 | 0 | 1,456 | -- | -- |
W03 | 06-18-2018 | 0 | 780 | -- | -- |
W03 | 07-09-2018 | 0/0 | 930 | 20:30 | -- |
W06 | 07-09-2018 | 54/4 | 867 | 19:15 | -- |
W10 | 06-18-2018 | 0 | 909 | -- | -- |
1,2W06-W10 | 07-26-2018 | 2 | 744 | -- | -- |
1,2W13-W10 | 07-25-2018 | 7 | 3,176 | -- | -- |
W18 | 06-18-2018 | 0 | 853 | -- | -- |
W19 | 06-18-2018 | 0 | -- | -- | 02:00 |
W19 | 07-11-2018 | 0/0 | -- | 623:21/23:10 | -- |
W22 | 06-19-2018 | 1 | 550 | -- | -- |
W22 | 07-11-2018 | 0 | -- | 23:05 | -- |
W24 | 06-19-2018 | 0 | 331 | -- | -- |
WVR | 08-27-2018 | 0 | -- | 23:30 | -- |
W31 | 06-21-2018 | 0 | 597 | -- | -- |
W31 | 07-12-2018 | 0 | 673 | -- | -- |
WH04 | 06-19-2018 | 0 | -- | -- | 00:40 |
N4MR | 08-20-2018 | 0 | -- | 23:09 | -- |
4MR | 07-11-2018 | 0 | -- | 21:00 | -- |
4MR | 08-20-2018 | 0 | -- | 22:43 | -- |
S4MR | 08-20-2018 | 0 | -- | 22:43 | -- |
4M1 | 06-19-2018 | 0 | 390 | -- | -- |
4M2 | 06-19-2018 | 0 | 423 | -- | -- |
4M3 | 06-19-2018 | 0 | 410 | -- | -- |
Willow Creek | |||||
W59 | 06-21-2018 | 0 | 264 | -- | -- |
W59 | 07-10-2018 | 0 | 723 | -- | -- |
Fletcher Creek and tributaries | |||||
B39 | 06-20-2018 | 0 | 842 | -- | -- |
B03 | 06-19-2018 | 0 | 850 | -- | -- |
B08 | 06-20-2018 | 0 | 692 | -- | -- |
B12 | 06-20-2018 | 0 | 914 | -- | -- |
AR | 08-27-2018 | 0 | -- | 22:43 | -- |
GR01 | 06-20-2018 | 0 | 756 | -- | -- |
LW01 | 06-19-2018 | 0 | 850 | -- | -- |
LW02 | 06-19-2018 | 0 | 850 | -- | -- |
LW02 | 07-10-2018 | 1 | -- | 23:10 | -- |
MC02 | 06-19-2018 | 0 | 850 | -- | -- |
JR | 08-27-2018 | 0 | -- | 27:10 | -- |
DHR | 07-9-2018 | 0 | -- | 16:05 | -- |
B38 | 06-20-2018 | 0 | 862 | -- | -- |
B41 | 07-09-2018 | 0 | -- | 16:50 | -- |
4TF | 07-09-2018 | 0 | -- | -- | -- |
Boles Creek and tributaries | |||||
BM | 07-25-2018 | 0/56 | 592 | 21:30 | -- |
B19 | 07-25-2018 | 0/0 | 652 | 24:07 | -- |
B20/21 | 07-11-2018 | 0 | 591 | -- | -- |
B20/21 | 07-25-2018 | 0/0 | 241 | 22:45 | -- |
B22 | 07-25-2018 | 0/0 | 805 | 20:22 | -- |
B24 | 06-21-2018 | 0 | 995 | -- | -- |
B24 | 07-11-2018 | 0/0 | 460 | 22:50 | -- |
B25 | 06-21-2018 | 0 | 1019 | -- | -- |
B29 | 06-21-2018 | 0 | 929 | -- | -- |
B29 | 07-10-2018 | 0/0 | 531 | 26:55 | -- |
B30 | 07-10-2018 | 0/0 | 850 | 27:00 | -- |
Mowitz Creek | |||||
MWC01 | 08-29-2018 | 0/0 | 2150 | 22:30 | -- |
Sites were longer sections of stream; the beginning and end coordinates are given in
Sample location was only sampled for suckers and no bycatch was recorded.
Sample location was sampled immediately after shocking the longer section of the stream.
Sample location was visited but not sampled because it was dry.
Three of the individual suckers captured by electrofishing were also captured in the trap nets.
Two trap nets were set.
Expanded view of insert A from
Figure 4. Expanded view of insert A from figure 2 showing sampling sites identified and labeled with site designation, Clear Lake, California, 2018
Expanded view of insert B from
Figure 5. Expanded view of insert B from figure 2 showing sampling sites identified and labeled with site designation, Clear Lake, California, 2018
Expanded view of insert C from
Figure 6. Expanded view of insert C from figure 2 showing sampling sites identified and labeled with site designation, Clear Lake, California, 2018
Size of suckers in the Clear Lake drainage varied depending on capture location. The majority of suckers captured (63 fish; 86 percent) were age-0 to age-3 and were less than 200 mm SL (
Length frequencies of the most abundant nontarget species captured in the Clear Lake drainage, California, 2018. [mm, millimeters]
Figure 10. Graphs showing length frequencies of the most abundant nontarget species captured in the Clear Lake drainage, California, 2018
Length frequency of suckers in millimeters (mm) captured in the Clear Lake drainage, California, 2018. Area locations are given in
Figure 7. Graph showing length frequency of suckers in millimeters captured in the Clear Lake drainage, California, 2018
Suckers in the Clear Lake drainage were identified as shortnose or Klamath largescale suckers. Suckers larger than 200 mm SL (
The habitat was similar at all locations, regardless of suckers captured. Suckers were mostly present in runs or pools with fine substrate and moderate submerged vegetation in depths ranging from 0.5 to 3.0 m. The riparian vegetation was generally meadow habitat with sedges and rushes lining the stream banks. At sites where suckers were captured (and most other sites), livestock were not present at the time of sampling, but there were recent signs of livestock. However, at site W13-10 cattle appeared to have limited access to the stream and signs of cattle were not as abundant. There was large woody debris at 50 percent of the sites where suckers were captured compared to 17 percent of the sites where no suckers were captured. There was a moderate amount of submerged vegetation at 71 percent of sites where suckers were captured, compared to 44 percent of the sites where no suckers were captured. All other habitat parameters appeared similar between sites where suckers were captured, and suckers were not captured.
Water quality was similar among sampling sites and parameters were within ranges known to support suckers (
Table 4. Water quality point sample measurements collected during surveys in the Clear Lake drainage, California, 2018
[Coordinates for sites are given in
Site name | Date |
Time |
pH | Dissolved |
Dissolved oxygen |
Temperature |
Specific |
North Fork Willow Creek and tributaries | |||||||
---|---|---|---|---|---|---|---|
UN01 | 06-20-2018 | 11:01 | 7.32 | 7.66 | 92 | 14.44 | 110 |
UN02 | 06-20-2018 | 11:32 | 7.70 | 9.29 | 128 | 21.17 | 111 |
3LVD01 | 06-20-2018 | 15:25 | 7.65 | 10.29 | 133 | 18.48 | 202 |
LVD03 | 06-20-2018 | 14:35 | 7.34 | 8.79 | 120 | 21.16 | 177 |
LVD04 | 06-20-2018 | 12:53 | 6.88 | 5.02 | 62 | 16.15 | 155 |
LVD06 | 06-20-2018 | 13:36 | 7.15 | 8.05 | 103 | 17.70 | 154 |
1LVD01-LVD04 | 07-27-2018 | 08:15 | 7.23 | 5.79 | 77 | 19.89 | 228 |
1LVD04-W01 | 07-26-2018 | 09:15 | 6.78 | 4.12 | 58 | 22.34 | 237 |
W03 | 06-18-2018 | 12:03 | 7.62 | 8.86 | 98 | 11.44 | 186 |
W03 | 07-09-2018 | 12:20 | 7.98 | 7.90 | 102 | 18.43 | 224 |
3W06 | 07-09-2018 | 13:14 | 7.68 | 8.88 | 115 | 18.60 | 228 |
W10 | 06-18-2018 | 13:49 | 7.81 | 10.27 | 119 | 13.41 | 207 |
1,3W6-W10 | 07-26-2018 | 11:30 | 7.56 | 10.72 | 146 | 21.07 | 231 |
1,3W13-W10 | 07-25-2018 | 10:00 | 7.59 | 8.05 | 115 | 23.51 | 226 |
W18 | 06-18-2018 | 14:30 | 7.47 | 7.85 | 98 | 17.08 | 174 |
W19 | 06-18-2018 | 08:25 | 6.85 | 5.51 | 66 | 15.00 | 152 |
W19 | 07-11-2018 | 09:15 | 7.06 | 6.25 | 81 | 19.02 | 178 |
3W22 | 06-19-2018 | 09:15 | 6.88 | 7.54 | 91 | 15.50 | 152 |
W22 | 07-11-2018 | 09:50 | 7.15 | 8.00 | 104 | 19.27 | 177 |
W24 | 06-19-2018 | 10:15 | 7.05 | 5.94 | 72 | 15.68 | 153 |
WVR | 08-27-2018 | 12:00 | 6.88 | 5.01 | 60 | 15.21 | 280 |
W31 | 06-21-2018 | 07:35 | 7.20 | 5.65 | 69 | 16.57 | 189 |
W31 | 07-12-2018 | 11:30 | 7.25 | 8.47 | 118 | 23.25 | 228 |
WH04 | 06-19-2018 | 16:20 | 7.24 | 8.77 | 108 | 16.35 | 202 |
N4MR | 08-20-2018 | 09:09 | 7.15 | 5.21 | 64 | 16.36 | 156 |
4MR | 07-11-2018 | 12:46 | 8.21 | 11.00 | 153 | 22.97 | 105 |
4MR | 08-20-2018 | 10:18 | 7.54 | 4.15 | 52 | 17.35 | 134 |
S4MR | 08-20-2018 | 09:55 | 6.85 | 2.63 | 33 | 17.88 | 172 |
4M1 | 06-19-2018 | 13:23 | 7.00 | 11.40 | 140 | 16.50 | 99 |
4M2 | 06-19-2018 | 14:37 | 7.02 | 14.25 | 176 | 16.85 | 94 |
4M3 | 06-19-2018 | 14:05 | 6.82 | 11.93 | 148 | 17.16 | 90 |
Willow Creek | |||||||
W59 | 06-21-2018 | 11:30 | 8.16 | 11.00 | 143 | 20.17 | 198 |
W59 | 07-10-2018 | 17:00 | 8.74 | 14.32 | 210 | 26.40 | 220 |
Fletcher Creek and tributaries | |||||||
B39 | 06-20-2018 | 16:10 | 225 | ||||
B03 | 06-19-2018 | 13:31 | 7.81 | 10.56 | 132 | 17.02 | 182 |
B08 | 06-20-2018 | 12:15 | 222 | ||||
B12 | 06-20-2018 | 07:30 | 218 | ||||
AR | 08-27-2018 | 10:30 | 9.80 | 9.72 | 120 | 16.05 | 145 |
GR01 | 06-20-2018 | 17:00 | 223 | ||||
LW01 | 06-19-2018 | 07:49 | 7.66 | 9.34 | 101 | 10.12 | 136 |
LW02 | 06-19-2018 | 09:47 | 7.34 | 9.47 | 106 | 12.13 | 141 |
3LW02 | 07-10-2018 | 08:00 | 7.16 | 7.23 | 82 | 12.50 | 167 |
MC02 | 06-19-2018 | 11:14 | 7.40 | 8.35 | 113 | 20.92 | 79 |
JR | 08-27-2018 | 09:15 | 8.49 | 8.57 | 108 | 17.43 | 104 |
DHR | 07-09-2018 | 18:29 | 8.61 | 10.60 | 152 | 24.11 | 99 |
B38 | 06-20-2018 | 09:50 | 218 | ||||
B41 | 07-9-2018 | 16:40 | 8.31 | 10.10 | 136 | 20.85 | 71 |
TF | 07-9-2018 | 17:23 | dry | dry | dry | dry | |
Boles Creek and tributaries | |||||||
3BM | 07-25-2018 | 13:31 | 7.94 | 14.73 | 219 | 26.36 | 158 |
B19 | 07-25-2018 | 10:00 | 8.00 | 5.25 | 71 | 21.46 | 194 |
B20/21 | 07-11-2018 | 12:16 | 8.21 | 9.85 | 137 | 22.79 | 124 |
B20/21 | 07-25-2018 | 10:58 | 7.70 | 6.96 | 99 | 23.84 | 134 |
B22 | 07-25-2018 | 12:09 | 6.98 | 5.84 | 83 | 23.75 | 175 |
B24 | 06-21-2018 | 10:00 | 6.77 | 5.68 | 77 | 21.66 | 130 |
B24 | 07-11-2018 | 08:52 | 7.15 | 7.24 | 98 | 21.78 | 143 |
B25 | 06-21-2018 | 11:33 | 6.78 | 5.82 | 71 | 16.60 | 134 |
B29 | 06-21-2018 | 07:15 | 6.46 | 1.21 | 14 | 13.73 | 160 |
B29 | 06-21-2018 | 12:45 | 8.55 | 12.24 | 169 | 22.84 | 128 |
B30 | 07-10-2018 | 13:20 | 7.56 | 7.47 | 100 | 21.35 | 129 |
Mowitz Creek | |||||||
MWC01 | 08-29-2018 | 08:15 | 6.92 | 6.53 | 74 | 13.70 | 232 |
These sites were longer sections of stream; the beginning and end coordinates are given in
YSI Sonde was not working and temperature was taken by a thermometer.
Sites where suckers were captured.
Table 5. General statistics for temperature readings in degrees Celsius from HOBO® loggers at six sites, two drainages, in California from June 21, 2018 through July 31, 2018
[Sites are ordered from upstream to downstream for each drainage.
Drainage | Creek | Site | Mean | SD | Min | Max |
Northern | Willow | W03 | 19.4 | 2.3 | 13.2 | 25.0 |
Northern | Willow | W31 | 22.2 | 2.2 | 15.7 | 26.6 |
Northern | Willow | W59 | 23.2 | 2.7 | 17.4 | 30.3 |
Southern | Fletcher | B12 | 20.0 | 1.6 | 15.2 | 25.0 |
Southern | Boles | B24 | 23.4 | 1.6 | 18.9 | 27.1 |
Southern | Boles | B29 | 23.0 | 2.6 | 17.3 | 30.3 |
Comparisons of water quality between sites where suckers were captured and where suckers were not captured in the Clear Lake drainage, California, 2018. Boxes show the 25th and 75th percentiles, bold lines in the boxes are the median, whiskers indicate the 5th and 95th percentiles, and the dots indicate outliers. [N, number of suckers;°C, degrees Celsius;%, percent; µS/cm, microsiemens per centimeter.]
Figure 8. Box plot comparisons of water quality between sites where suckers were captured and where suckers were not captured in the Clear Lake drainage, California, 2018
Daily mean temperatures (lines) with the daily range (shaded areas) of water temperatures at the six sites where HOBO® loggers were placed in the Clear Lake drainage, California, 2018. Sites were (a) W03, (b) W31, and (c) W59 from the Northern drainage, and (d) B12, (e) B24, and (f) B29 from the Southern drainage. [°C, degrees Celsius.]
Figure 9. Graphs showing daily mean temperatures with the daily range of water temperatures at the six sites where HOBO® loggers were placed in the Clear Lake drainage, California, 2018
Nonnative green sunfish (
Table 6. Numbers of fish species captured in each of the major creeks and their tributaries in the Clear Lake drainage, California, 2018
Common name | Scientific name | Willow |
Fletcher |
Boles |
Mowitz |
All |
Blue chub | 4 | 8 | 3 | 0 | 15 | |
Fathead minnow | 301 | 0 | 13 | 0 | 314 | |
Speckled dace | 141 | 95 | 0 | 0 | 236 | |
Tui chub | 102 | 12 | 830 | 4 | 948 | |
Sacramento perch | 0 | 0 | 0 | 12 | 12 | |
Green sunfish | 862 | 530 | 789 | 332 | 2,513 | |
Bluegill | 0 | 29 | 0 | 50 | 79 | |
Largemouth bass | 2 | 42 | 161 | 0 | 205 | |
Black crappie | 0 | 12 | 0 | 0 | 12 | |
Lamprey sp. | 4 | 0 | 0 | 0 | 4 | |
Rainbow trout | 0 | 34 | 0 | 0 | 34 | |
Sculpin sp. | 6 | 9 | 0 | 0 | 15 | |
Bullhead catfish | 2,741 | 74 | 73 | 0 | 2,888 |
Twelve of the 15 nontarget species captured during this study had at least one individual measured (
Table 7. Number of nontarget fish measured in the Clear Lake tributaries and the mean, minimum, and maximum standard length for each species, California, 2018.
[
Common name | Mean |
Minimum |
Maximum |
|
Blue chub | 12 | 53 | 28 | 90 |
Fathead minnow | 46 | 52 | 38 | 63 |
Speckled dace | 39 | 66 | 48 | 91 |
Tui chub | 47 | 78 | 37 | 127 |
Sacramento perch | 8 | 105 | 71 | 132 |
Green sunfish | 188 | 83 | 22 | 163 |
Bluegill | 15 | 78 | 62 | 92 |
Largemouth bass | 17 | 80 | 34 | 232 |
Rainbow trout | 11 | 150 | 31 | 225 |
Sculpin sp. | 11 | 58 | 27 | 83 |
Bullhead catfish | 72 | 124 | 33 | 229 |
Figure 10. Graphs showing length frequencies of the most abundant nontarget species captured in the Clear Lake drainage, California, 2018
Figure 10. Graphs showing length frequencies of the most abundant nontarget species captured in the Clear Lake drainage, California, 2018.
Suckers were mostly found in pools and runs within the Gerber Reservoir drainage with fine substrate, little submerged vegetation, and in depths ranging from 0.5 to 1.0 m. Riparian vegetation was generally meadow habitat in Barnes Valley and Long Branch Creeks, and alders in Lapham Creek. Water quality was similar among sampling sites and fell within ranges known to be acceptable for suckers (
Table 8. Water quality point sample measurements collected where suckers were captured and at the end of the survey in Gerber Reservoir drainage, Oregon, 2018
[Coordinates for sites where suckers were captured are given in
Stream | Site | Date |
Time |
pH | Dissolved |
Dissolved oxygen |
Temperature |
Specific conductance |
Barnes Valley Creek | BVC01 | 08-20-2018 | 12:53 | 7.62 | 5.90 | 77 | 18.97 | 299 |
Barnes Valley Creek | BVC01 | 08-20-2018 | 14:13 | 7.46 | 6.99 | 93 | 20.01 | 275 |
Lapham Creek | LHC01 | 08-31-2018 | 11:02 | 6.91 | 5.56 | 65 | 13.50 | 105 |
Lapham Creek | LHC01 | 08-31-2018 | 12:00 | 7.14 | 8.57 | 102 | 14.59 | 105 |
Long Branch Creek | LBC01 | 08-30-2018 | 10:52 | 5.60 | 5.45 | 64 | 14.10 | 260 |
Long Branch Creek | LBC01 | 08-30-2018 | 11:22 | 6.81 | 3.72 | 45 | 15.75 | 352 |
Long Branch Creek | LBC01 | 08-30-2018 | 12:01 | 6.54 | 5.78 | 66 | 13.01 | 267 |
Long Branch Creek | LBC02 | 08-22-2018 | 10:37 | 8.19 | 8.21 | 100 | 15.84 | 276 |
Long Branch Creek | LBC02 | 08-22-2018 | 12:54 | 7.92 | 8.03 | 97 | 15.30 | 272 |
Long Branch Creek | LBC02 | 08-22-2018 | 12:30 | 6.75 | 3.54 | 44 | 16.63 | 257 |
Table 9. Electrofishing effort and suckers captured in tributaries in the Gerber Reservoir drainage, Oregon, 2018.
[
Stream | Site | Effort |
Suckers |
CPUE |
Barnes Valley Creek | BVC01 | 04:04 | 26 | 0.11 |
Lapham Creek | LHC01 | 02:25 | 2 | 0.01 |
Long Branch Creek | LBC01 | 02:24 | 8 | 0.06 |
Long Branch Creek | LBC02 | 02:50 | 8 | 0.05 |
Table 10. Locations where suckers were captured in the Gerber Reservoir drainage, Oregon, 2018
Stream | Site | Latitude | Longitude |
Barnes Valley Creek | BVC01 | 42°10'09.8" | 120°58'02.8" |
Lapham Creek | LHC01 | 42°11'15.0" | 120°52'28.0" |
Long Branch Creek | LBC01 | 42°12'09.7" | 120°59'47.0" |
Long Branch Creek | LBC01 | 42°12'11.5" | 120°59'49.0" |
Long Branch Creek | LBC02 | 42°11'27.0" | 121°00'29.2" |
Long Branch Creek | LBC02 | 42°11'28.4" | 121°00'24.9" |
Suckers captured in the tributaries to Gerber Reservoir ranged from 52 to 259 mm SL and were age-0 to age-6. The majority of suckers captured (89 percent) in the Gerber Reservoir tributaries were less than 200 mm SL and were not identified to species using morphology (
Length frequency of suckers captured at four sample sites in the Gerber Reservoir drainage, Oregon, August 2018. Site locations are listed in
Figure 11. Graph showing length frequency of suckers captured at four sample sites in the Gerber Reservoir drainage, Oregon, August 2018
We did not capture Lost River suckers during our study; however, previous studies (
Shortnose suckers in Clear Lake do not resemble the shortnose suckers in Upper Klamath Lake, and since these suckers were initially described in Clear Lake, there has been a debate as to the proper classification of the species as shortnose, Klamath largescale, or hybrids (
During our study and the previous studies, the majority of suckers were captured in lentic waters with mud and fine substrate.
The majority of juvenile suckers we captured in the Clear Lake drainage were found in ponded water within Boles Meadow, behind a water retention structure. The standing water was evaporating and drying rapidly leading to increased water temperatures. Water temperatures were warm and we suspect that this site dried out after our visit, making the survival of the fish found in Boles Meadow unlikely.
During this study suckers were primarily captured in depths of 0.5 to 3.0 m, with most captured in waters of 1.0 m or less.
Although this study,
Consistent with
The fish assemblage changed from primarily natives in the previous studies to primarily nonnatives in the present study. In 1973 and 1975 the fish community was primarily composed of tui chub and speckled dace with a few sculpin (
The effort at the Gerber Reservoir tributaries was limited; however, the CPUE of suckers captured was greater than in Clear Lake tributaries. Suckers were captured at all sampled sites, with the majority of suckers captured in pools within the creeks. Past studies have also found that suckers were primarily found in pools within the creeks (
Although the current study occurred in a very dry year with potentially restricted distribution of suckers, due to poor connectivity, the results from this study were similar to the past studies, except that suckers were not collected in the small reservoirs during this study. The previous studies collected Lost River suckers, but this study did not, this difference may have been due to the current study occurring during a dry year. Morphological identifications from the previous studies and this study, indicated that shortnose suckers were captured in the tributaries. However, recent genetic research indicated that suckers morphologically identified as shortnose suckers in the Clear Lake drainage, were determined to be more genetically similar to Klamath largescale suckers in the Upper Klamath Lake drainage (
Data collection and project implementation were made possible with the help of the U.S. Geological Survey (USGS) Klamath Falls Field Station staff including, Joshua Hargrove, Justin Howard, Rachael Paul-Wilson, and David Smith. Alta Harris (USGS) provided database support.
Publishing support provided by the U.S. Geological Survey
Science Publishing Network, Tacoma Publishing Service Center
For more information concerning the research in this report,
contact the
Director, Western Fisheries Research Center
U.S. Geological Survey
6505 NE 65th Street
Seattle, Washington 98115-5016