SECTION NO. 1
Fluminicola n. sp. 1

Draft Management Recommendations

for

Klamath Pebblesnail (Fluminicola n. sp. 1)

v. 2.0

by

Roger Monthey,

USDI Bureau of Land Management

Salem, Oregon

December 1998

TABLE OF CONTENTS

EXECUTIVE SUMMARY

Species: Fluminicola n. sp. 1 - undescribed (Klamath pebblesnail)

Taxonomic Group: Mollusk (Phylum Mollusca; Class Gastropoda, Subclass Prosobranchia; Family Hydrobiidae)

ROD Components: Survey Strategies 1 and 2 and listed in the Standards and Guides for protection from grazing.

Other Management Status: Oregon Natural Heritage Program List 1; BLM Sensitive Species in Oregon.

Range: In Oregon the Klamath pebblesnail occurs in Upper Klamath Lake and major spring-fed tributaries, Klamath County, Oregon, including sites in the Winema and Rogue River National Forests; and the Upper Klamath Lake National Wildlife Refuge. It is suspected to occur in the Klamath Falls Resource Area of the Lakeview District. It also occurs sporadically in the middle and upper sections of the Klamath River to the confluence with the Shasta River, Siskiyou County, California. It is suspected to occur in the BLM Redding District and the Klamath National Forest.

Specific Habitat: This species is generally found in bodies of water with gravel-boulder substrates and some flow. Like other Fluminicola, it prefers cold oligotrophic water with high dissolved oxygen. It is found rarely in springs and avoids areas with dense macrophyte beds.

Threats:

• Nutrient enrichment resulting in eutrophication of Upper Klamath Lake.
• Disruption of bottom substrates of Upper Klamath Lake (which disturbs snail populations and increases sedimentation).
• Reduced oxygen levels of Upper Klamath Lake at periodic intervals.
• Water pollution.
• Decreases in water flow.
• Excessive sedimentation and eutrophication of springs from a variety of activities such as logging, mining, road and railroad grade construction, and grazing may smother preferred substrates and may impair egg-laying or survivorship of eggs or young.
• Channeling for irrigation systems and for log transport.

Management Recommendations:

1. Manage to protect the required environmental conditions [e.g., high dissolved oxygen at or near saturation levels, low sediment, cool temperatures (i.e., below 18^oC)] at known sites. Activities that may impact these environmental conditions include dredging, grazing, nutrient enrichment, water pollution, decreased water flow as a result of irrigation or other activities, and construction activities (e.g., dams, roads).
2. Maintain and/or restore riparian vegetation that aids in maintaining cool water temperatures by providing shade, reducing sedimentation impacts, and providing litter fall nutrients to energy pathways in aquatic ecosystems.
3. Avoid or mitigate for activities (e.g., logging, grazing, mining, construction activities) that could significantly increase sedimentation or potential for eutrophication of occupied sites.

Information Needs: Additional surveys should be conducted to locate populations in areas with potential suitable habitat. More monitoring or research is needed on habitat requirements of these species. Develop a collection of voucher specimens for appropriate administrative units within the range of these species. Provide additional training opportunities for identifying mollusk species and conducting surveys within the appropriate administrative units. Consultation with a mollusk taxonomist to ensure proper identification may be very significant for this taxon. Determine the minimum instream flow requirements necessary to maintain environmental conditions within physiological limits.

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I. NATURAL HISTORY

A. Taxonomic/Nomenclatural History

Fluminicola n. sp. 1 is a rare aquatic snail belonging to the family Hydrobiidae. The common name for this family is "spring snails," which is an allusion to the type of habitat where they are primarily found. This is a polytypic family with many described and undescribed species.

The following discussion is after Frest and Johannes (1995). This species is within the subfamily Lithoglyphinae. North American snails within this subfamily closely resemble some foreign groups. Similarities in the male reproductive system and shell led Taylor (1966a, 1966b, 1981, 1985) to consider these snails as representatives of the European Lithoglyphus. However, Thompson (1984), after detailed studies, concluded that Fluminicola is likely distinct, but there is still a need for detailed anatomical and conchological examination.

Frest and Johannes (1996) noted that the malacofauna of the Upper Klamath Lake drainage can be divided into several groups: 1. those species common throughout much of North America, 2. those species that likely originated in Upper Klamath Lake and immediately adjacent drainages, and 3. those species that originated in or at least are largely confined to the Great Basin and peripheral internal drainages. Taylor (1985) noted similarities in the malacofauna of the Upper Klamath and the Pit River (and hence Sacramento drainage). However, he also noted several lake forms in Upper Klamath Lake that, for habitat reasons, have no parallel in the Sacramento drainage. Frest and Johannes (1996) also noted that the freshwater malacofauna of the Upper Klamath drainage is evidently quite distinct from that characteristic of most Pacific Northwest coastal streams. The high rates of endemism and the Great Basin element apparently have few close parallels.

B. Species Description

1. Morphology

The following is taken from Frest and Johannes (1993): This middle Klamath-Upper Klamath Lake drainage taxon has a comparatively large, (to 1 cm), rather tall subglobose conch, with 3-1/2 rather rapidly expanding whorls, deeply impressed suture, and greenish or yellow periostracum. Later whorls are unevenly convex, appearing slightly shouldered in side view. The shell is thick and opaque white. The columella is moderately thickened; the parietal wall slightly thickened; and the basal and outer portions of the aperture are also commonly slightly reinforced. A basal crescent is generally lacking; the umbilicus is closed but not callused. Dorsal cephalic tentacles, upper snout, and eye patches are almost black, as are anterior and posterior margins of the foot; the rest of the body is almost pigmentless; and the penis is sickle-shaped, moderately large, and with few wrinkles.

2. Reproductive Biology

Information on life history is very sparse, but Fluminicola n. sp. 1 is probably similar to other Fluminicola species that have been better studied. Typically, members of the genus are dioecious (i.e., have separate sexes) and semelparous (i.e., breed only once in their lifetime and then die). Individuals have a life span of one year, with 90 percent or more of the population turning over annually. Surviving individuals are generally those that do not breed during their first year. Eggs are laid in the spring and hatch in approximately 2-4 weeks. Sexual maturity is reached by late summer after a few months of growth. Individuals overwinter as adults and do not disperse widely, so populations remain very localized in their distribution.

3. Ecology

All of the Fluminicola species are rare aquatic snails belonging to the family Hydrobiidae. Hydrobiid snails have gills that make them dependent upon dissolved oxygen in the water in which they live. Like most hydrobiid snails, this species is highly sensitive to oxygen deficits, elevated water temperatures, and sedimentation. Major predators include waterfowl, amphibians, turtles, sculpins and trout. Typically, many individuals are infected with trematode parasites.

This species sometimes occurs with other endemic Fluminicola spp., Lanx alta or Lanx klamathensis, Lyogyrus spp., Helisoma (Carinifex) newberryi, or Pisidium ultramontanum. It is predominantly a perilithon grazer and lithophile (preferring rocky environments) (Frest and Johannes 1996).

C. Range, Known Sites

The current range in Oregon includes: Upper Klamath Lake and major spring-fed tributaries, Klamath County, Oregon, including sites in the Winema and Rogue River National Forests; Upper Klamath Lake National Wildlife Refuge; and the Klamath Falls Resource Area of the Lakeview District (Frest and Johannes 1996). This species also occurs in California in the Klamath River, Siskiyou County (suspected to occur in the BLM Redding District and Klamath National Forest). According to Frest and Johannes (1996), it was apparently more widespread in the past. Its distribution in the middle and upper Klamath River is now very sporadic because it is absent from impoundments and polluted stretches. Frest and Johannes collected this undescribed species at 14 sites in the Upper Klamath Drainage of Oregon. A detailed description of these sites is found in Appendix A of Frest and Johannes (1996).

D. Habitat Characteristics and Species Abundance

This species generally occurs with gravel-boulder substrate spring influx, and some flow (Frest and Johannes 1996). Like most Fluminicola, it prefers clear, cold, oligotrophic, flowing water with high dissolved oxygen. It is found only rarely in springs and avoids areas with dense macrophytes such as Myriophyllum and Elodea. It also avoids areas subject to eutrophication or periodic hypoxic (low oxygen levels) episodes.

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II. CURRENT SPECIES SITUATION

A. Why Species is Listed under Survey and Manage Standards and Guidelines

This undescribed species is locally endemic within its range (i.e., it occurs in small, isolated areas). Partially because of the high degree of endemism associated with this species, the FEMAT analysis (USDA, Forest Service and USDI, Bureau of Land Management 1994) concluded this species has low likelihood of attaining stable, well distributed populations. It is rarely collected in localized areas of Upper Klamath Lake with spring influx or influence, even though dredged shells indicate it was once common in the lake. Other springs in its range have been adversely affected by heavy grazing and development of irrigation systems, resulting in sedimentation and eutrophication which have eliminated or greatly reduced this species. Its historic distribution was apparently more widespread than what is currently observed (Frest and Johannes 1996).

B. Major Habitat and Viability Considerations

The major viability considerations for this species include loss of populations due to factors such as nutrient enrichment, resulting in eutrophication, sedimentation, reduced water flow and volume, and water pollution. Examples of impacts likely include grazing, development of irrigation systems, chemical spills, dredging of lake bottom substrates, construction of roads, railroads, and dams, and substrate disruption by mining operations or other activities.

Much of Upper Klamath Lake is strongly eutrophied, so that live populations of this species are restricted to areas with spring influx or influence, even though dredged shells indicate high abundance and wide distribution in the lake (Frest and Johannes 1996). The species does not occur in areas subject to periodic hypoxic episodes. Springs in the lake bottom proper are badly affected by past dredging to facilitate log transport and by current severe nutrient enhancement and sedimentation. Many springs and their outflows are heavily grazed, channelized, or connected to irrigation canal systems. Sedimentation and eutrophication either eliminates or greatly reduces the abundance of this species.

C. Threats to the Species

• Nutrient enrichment resulting in eutrophication, especially of Upper Klamath Lake.
• Disruption of bottom substrates of Upper Klamath Lake (which disturbs snail populations and increases sedimentation).
• Reduced oxygen levels of Upper Klamath Lake at periodic intervals.
• Water pollution.
• Decreases in water flow or above average fluctuations in lake levels.
• Excessive sedimentation and eutrophication of springs from a variety of activities such as logging, mining, road and railroad grade construction, and grazing may smother substrates preferred by these species and may impair egg-laying or survivorship of eggs or young.
• Channeling for irrigation systems and for log transport.

D. Distribution Relative to Land Allocations

Some known occurrences of this species are within or near the Late-Successional Reserves (RO227, R0228, and R0229) on the west side of Upper Klamath Lake. It also possibly occurs in administratively withdrawn sites along the Klamath River. One known site occurs within the Matrix allocation of the Winema National Forest. Sites on the Klamath Falls Resource Area of the Lakeview BLM District are included in Late-Successional Reserves. For more precise locations of known sites relative to land allocations, field units should refer to the Survey and Manage Database and local GIS systems.

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III. MANAGEMENT GOALS AND OBJECTIVES

A. Management Goals for the Taxon

The overall management goal for Fluminicola n. sp. 1 is to assist in maintaining species viability.

B. Specific Objectives

• Maintain appropriate water quantity (e.g., flow) and quality (e.g., high dissolved oxygen, low water temperatures, low sedimentation) conditions necessary to support viable populations of this species. Avoid or mitigate for dredging, channeling, water diversions, dam construction, and other management activities that could increase sedimentation or eutrophication.
• Maintain riparian vegetation to maintain suitable ecological values.
• Maintain integrity of spring, lakebed or streambed by preventing adverse sedimentation impacts.

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IV. HABITAT MANAGEMENT

A. Lessons from History

Historically, the Oregon geographic area occupied by this species has been generally impacted by agriculture, logging, and grazing activities. These activities likely contributed to the specific degradation of water quality (e.g., elevated water temperatures, eutrophication, lowered dissolved oxygen, increased sedimentation) and suitable habitat important to this species. Reservoir and hydroelectric development (thereby increasing water temperatures and sedimentation) on the Klamath River has extirpated the species from some of its historic geographic range, especially in California.

B. Identification of Habitat Areas for Management

All known or newly discovered occupied sites on federal lands should be managed. Identify the habitat areas around known site locations, including all habitat featues that contribute to the environmental conditions important to the species at the known site.

In most cases, the Riparian Reserve standards and guides for buffer widths and meeting Aquatic Conservation Strategy objectives will be sufficient for management within these areas. In situations where RRS and ACS do not apply or are not considered sufficient (e.g., wtlands less than 1 acre, springs and seeps) apply the standards and guides for perennial stream widths to determine the size of the area. Where wind firmness is a problem, habitat area widths may need to be increased to protect species habitat conditions.

C. Management Within Habitat Areas

1. Generally, maintain and restore productivity and resiliency of riparian and aquatic ecosystems in order to achieve the Aquatic Conservation Strategy objectives.
2. Maintain water temperatures below 65F (or 18C) to avoid thermal stress and ensure adequate availability of oxygen. (65 represents the critical threshold for trout and in the absence of specific data for this species is used here.)
3. Maintain and/or restore native riparian plant communities that aid in maintaining cool water temperatures by providing shade, reducing sedimentation impacts, and providing litter fall nutrients to energy pathways in aquatic ecosystems.
4. Avoid activities which contribute to eutrophication.
5. Avoid harmful grazing activities (e.g., trampling of stream bottoms, water diversions).
6. Avoid dredging of lake and stream bottom substrates.
7. Avoid or mitigate for management activities that significantly increase sedimentation (e.g., road construction) in areas known to be inhabited by this species and in potential habitat.
8. Avoid water diversions (irrigation systems) or other activities that may reduce discharge, water temperature, or water quality at occupied sites.
9. Construction of additional dams should be avoided or at least located so as to minimize further impacts (such as elevated water temperatures, sedimentation) to existing populations.

D. Other Management Issues and Considerations

Should reestablishment be considered for this species, relatively pure colonies should be reintroduced and in fairly large numbers [i.e., in the range of several hundred to several thousand individuals per reintroduction site as recommended by Frest and Johannes (1995) for a similar species]. Fluminicola n. sp. 1 should be located in areas with suitable rock substrate; spring-influenced sites would be optimal.

No other management issues and considerations are identified at this time.

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V. RESEARCH, INVENTORY, AND MONITORING NEEDS

The objective of this section is to identify opportunities for additional information which could contribute to more effective species management. The content of this section has not been prioritized or reviewed as to how important the particular items are for species management. While the research, inventory, and monitoring information is not required, these recommendations should be addressed by a coordinating body at the Northwest Forest Plan level.

A. Data Gaps and Information Needs

• Conduct surveys to locate new populations of Fluminicola n. sp. 1 in areas identified as potential suitable habitat. Prioritize surveys in areas where management treatments or projects are scheduled or proposed.
• Conduct monitoring or research on habitat requirements of this species.
• Develop a collection of voucher specimens for appropriate administrative units within the range of this species.
• Monitor water temperatures at or in the vicinity of occupied sites using continuous reading thermometers, or at least maximum-minimum thermometers, to assure compliance.
• Monitor other environmental parameters (e.g., sedimentation, dissolved oxygen) that potentially affect this species.
• Determine the minimum instream flow requirements necessary to maintain environmental conditions within physiological limits.
• Develop keys and descriptions that allow field offices to accurately identify these species.

B. Research Questions

What is the formal description and type locality (as defined in the scientific literature) for this currently undescribed species?

Are the Survey and Manage provisions effective? If not, why, and what needs to be done differently?

What is the condition of existing populations with regard to absolute size and density?

What are the dispersal mechanisms of this species?

What are the specific habitat requirements of this species?

How does this species respond to changes in water quality conditions?

What implications, if any, does management for this species have on other species?

C. Monitoring Needs and Recommendations

Protocols for monitoring presently known populations. At a minimum, variables that should be monitored to track habitat quality include: 1. water temperature, 2. dissolved oxygen, 3. embeddedness of coarse substrates in finer sediments, and 4. discharge at springs and creeks, or current velocity at river sites.

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VI. REFERENCES

Frest, Terrence J. and Edward J. Johannes. 1993. Mollusc Species of Special Concern within the Range of the Northern Spotted Owl. Deixis Consultants, Final Report. Unpublished report prepared for the Forest Ecosystem Management Working Group, U.S.D.A. Forest Service; Pacific Northwest Region; Portland, OR. 98 pp. and 1 addendum.

_________. 1995. Freshwater Molluscs of the Upper Sacramento River System, California, with Particular Reference to the Cantara Spill. 1995 final report to California Department of Fish and Game. Deixis Consultants, Seattle, Washington.

_________. 1996. Freshwater Molluscs of the Upper Klamath Drainage, Oregon. 1996 yearly report to Oregon Natural Heritage Program. Deixis Consultants, Seattle, Washington. 72 pp., 1 figure, 6 tables, and 2 appendices.

Taylor, D. 1966a. Summary of North American Blancan Nonmarine Mollusks. Malacologia 4:1-172.

_________. 1966b. A Remarkable Snail Fauna from Coahuila, Mexico. Veliger 9: 152-228.

_________. 1981. Freshwater Mollusks of California: a Distributional Checklist. California Fish & Game 67:140-163.

_________. 1985. Evolution of Freshwater Drainages and Molluscs in western North America. In Smiley, C.J. (ed.). Late Cenozoic History of the Pacific Northwest. San Francisco, AAAS, Pacific Division, pp. 265-321.

Thompson, F. G. 1984. North American Freshwater Snail Genera of the Hydrobiid Subfamily Lithoglyphinae. Malacologia 25: 109-141.

USDA, Forest Service and Department of the Interior, Bureau of Land Management. 1994. Final Supplemental Environmental Impact Statement on Management of Habitat for Late-Successional and Old-Growth Forest Related Species within the Range of the Northern Spotted Owl. Appendix J2, Results of Additional Species Analysis. Portland, Oregon.

_________. 1994. Final Supplemental Environmental Impact Statement on Management of Habitat for Late-Successional and Old-Growth Forest Related species within the Range of the Northern Spotted Owl, Appendix A, Forest Ecosystem Management: An Ecological, Economic, and Social Assessment. Portland, OR.