|Conservation Assessment for the
California Slender Salamander in Oregon
October 20, 2008
Deanna H. Olson
U.S.D.A. Forest Service Region 6 and U.S.D.I. Bureau of Land Management
Interagency Special Status and Sensitive Species Program
DEANNA H. OLSON is a research ecologist, USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR 97331
This Conservation Assessment was prepared to compile the published and unpublished information on the California slender salamander (Batrachoseps attenuatus). Although the best scientific information available was used and subject experts were consulted in preparation of this document, it is expected that new information will arise and be included. If you have information that will assist in conserving this species or questions concerning this Conservation Assessment, please contact the interagency Conservation Planning Coordinator for Region 6 Forest Service, BLM OR/WA in Portland, Oregon, via the Interagency Special Status and Sensitive Species Program website at http://www.fs.fed.us/r6/sfpnw/issssp/contactus/
Species: California slender salamander (Batrachoseps attenuatus)
Taxonomic Group: Amphibian
Other Management Status: U.S.D.A. Forest Service, Region 6 – Oregon Sensitive; U.S.D.I. Bureau of Land Management, Oregon – Oregon Sensitive; Oregon Department of Fish and Wildlife State Sensitive – Peripheral; NatureServe ranks this species as Globally widespread, abundant and secure (G5), Oregon State imperiled (S2); Oregon Natural Heritage Information Center - List 2 – taxa that are threatened with extirpation or presumed to be extirpated from the state of Oregon. Management of the species follows Forest Service 2670 Manual policy and BLM 6840 Manual direction.
Range: The species occurs in the Coast Ranges from the southwestern corner of Oregon to northwestern California. In Oregon, it is currently known from near the Rogue River to Highway 199 in Curry County. The Oregon range is about 52,000 ha (~128,400 ac). There are 28 site records total, with 8 on federal lands (Rogue River-Siskiyou National Forest).
Specific Habitat: This is a terrestrial salamander that does not need standing or flowing water for any part of its life cycle. This species can be found in a wide variety of habitats across its range including coniferous forests, oak woodlands, grasslands, chaparral, urban areas, and coastal scrublands. In Oregon, it is typically found in humid coastal evergreen forests, under surface cover including down wood, rocks and litter. In northwestern California, this species was reported to be more abundant in older forests compared to young forests, and abundance decreased with elevation and distance from the coast.
Threats: This species is little studied, so the threats listed here are based on expert opinion and information known about other terrestrial salamanders in the same general area. Land-use activities that affect surface microhabitats and microclimates may impact individuals or populations at occupied sites. In Oregon, forest management effects are the greatest concern. These salamanders are also likely adversely affected by chemicals, such as herbicides, pesticides and fertilizers. Stand replacement fire, disease, global climate change and population fragmentation may be additional concerns.
Management Considerations: Considerations for maintaining local populations include maintaining surface refugia and microclimates at occupied sites. Reducing the impact of forest management is a key consideration; canopy retention, down wood management and reduced substrate disturbance would benefit this species. The timing of activities to outside of the wet season when animals are surface-active is also a consideration for this species’ management.
Inventory, Monitoring, and Research Opportunities: Information gaps include delineation of the north-eastern distribution of the species, habitat associations, understanding threats to the species, and distribution of risk factors throughout the species range. Many of these gaps can be answered by using various techniques of inventory, monitoring and research.
TABLE OF CONTENTS
I. INTRODUCTION 4
Management Status 4
II. CLASSIFICATION AND DESCRIPTION 5
Species Description 5
III. BIOLOGY AND ECOLOGY 6
Life History 6
Breeding Biology 7
Range, Distribution, and Abundance 7
Population Trends 9
Ecological Considerations 10
Biological Considerations 11
IV. CONSERVATION 11
Land Use Allocations 11
Conservation Status 14
Known Management Approaches 14
Management Considerations 15
V. INVENTORY, MONITORING, AND RESEARCH OPPORTUNITIES 16
Data and Information Gaps 16
The primary goal of this conservation assessment is to provide the most up to date information known about this species including life history, habitat, and potential threats, and to describe habitat and site conditions that may be desirable to maintain if management of a particular site or locality for the species is proposed. This species is an endemic vertebrate to Oregon and California, with a known range in Oregon restricted to the southwest portion of the state. In Oregon, it is recognized as a potentially vulnerable species by various Federal agencies and by the State of Oregon because of its restricted range and its potential susceptibility to land management activities that occur within this portion of its range. The goals and management considerations of this assessment are specific to BLM and Forest Service lands in Oregon. The information presented here is compiled to help manage the species in accordance with Forest Service Region 6 Sensitive Species (SS) policy and Oregon/Washington Bureau of Land Management Special Status Species (SSS) policy. Additional information for Region 6 SS and Oregon BLM SSS is available on the Interagency Special Status Species website (www.fs.fed.us/r6/sfspnw/ISSSSP).
For lands administered by the Oregon/Washington Bureau of Land Management (OR/WA BLM), SSS policy (6840 manual and IM OR-91-57) details the need to manage for species conservation.
For Region 6 of the Forest Service, SS policy requires the agency to maintain viable populations of all native and desired non-native wildlife, fish, and plant species in habitats distributed throughout their geographic range on National Forest System lands. Management “must not result in a loss of species viability or create significant trends toward federal listing” (FSM 2670.32) for any identified SS.
While the synthesis of biological and ecological information for the species focuses on information from Oregon, range-wide references also are highly relevant and included. This Conservation Assessment relies on published accounts, reports, locality data from individuals and databases, and expert opinion, each noted as appropriate. Although information compiled here is not restricted to that coming from federal sources, the scope of the management considerations of this assessment are specific to BLM and Forest Service lands in Oregon. The range of the California slender salamander on federal lands in Oregon includes the westernmost part of the Rogue River-Siskiyou National Forest. It also may occur on lands administered by the Coos Bay District of the Bureau of Land Management.
It is listed by the: U.S.D.A. Forest Service, Region 6, as Oregon Sensitive; U.S.D.I. Bureau of Land Management, Oregon, as Oregon Sensitive; Oregon Department of Fish and Wildlife State as Sensitive-Peripheral; NatureServe as Globally widespread, abundant and secure (G5), Oregon State imperiled (S2); and Oregon Natural Heritage Information Center - List 2 – taxa that are threatened with extirpation or presumed to be extirpated from the state of Oregon. In California, it is not a State or Federal species of concern. Management of the species in Oregon follows Forest Service 2670 Manual policy and BLM 6840 Manual direction.
II. CLASSIFICATION AND DESCRIPTION