Final Report, the Xerces Society, Blue Mountains Terrestrial Mollusks Surveys
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1 Final Report to the Interagency Special Status / Sensitive Species Program (ISSSSP) from The Xerces Society for Invertebrate Conservation SPRING 2012 BLUE MOUNTAINS TERRESTRIAL MOLLUSK SURVEYS Assistance agreement L08AC13768, Modification 7 Robust lancetooth (Haplotrema vancouverense) from land adjacent to the North Fork Umatilla River, May 15, 2012. Photo by Alexa Carleton. Field work, background research, and report completed by Sarina Jepsen, Alexa Carleton, and Sarah Foltz Jordan, The Xerces Society for Invertebrate Conservation Species Identifications and Appendices III and IV completed by Tom Burke, Certified Wildlife Biologist September 28, 2012 2 Table of Contents Introduction…………………………………………………………………………………………………………………….. 3 Survey Protocol……………………………………………………………………………………………………………….. 3 Sites Surveyed and Survey Results…………………………………………………………………………………… 7 Potential Future Survey Work………………………………………………………………………………………….. 17 Acknowledgements…………………………………………………………………………………………………………. 17 References Cited……………………………………………………………………………………………………………… 17 Appendix I: Table of sites surveyed and species found…………………………………………………….. 19 Appendix II: Maps of sites surveyed and special status species found……………………………… 24 Appendix III: Discussion of taxa in families: Oreohelicidae and Polygyridae (by T. Burke)… 30 Appendix IV: Descriptions of mollusks collected (by Tom Burke)……………………………………… 47 3 Introduction Sarina Jepsen and Alexa Carleton (Xerces Society) conducted surveys for terrestrial mollusks in May of 2012 in the Blue Mountains on land managed by the Umatilla National Forest (Walla Walla and North Fork John Day Ranger Districts) and the Bureau of Land Management (Vale District). Tom Burke (Certified Wildlife Biologist) identified all specimens. The surveys targeted four special status snail species: Blue mountainsnail (Oreohelix strigosa delicata ‐ STR), Umatilla megomphix (Megomphix lutarius ‐ STR), Humped coin (Polygyrella polygyrella ‐ OR‐STR, WA‐ SEN), and Dryland forestsnail (Allogona ptychophora solida ‐ WA‐STR). Two of the four target species were found: O. s. delicata was collected from the South Fork Walla Walla River and M. lutarius was collected from the North Fork John Day River. Before this survey, Megomphix lutarius was thought to be possibly extinct, as it had not been collected since the 1930s (Baker 1932). In addition to the target species, six other special status species were found on land managed by the BLM or USFS during this survey, including: Cryptomastix hendersoni (SEN), Cryptomastix populi (SEN), Helicodiscus salmonaceus (WA‐SEN), Pristiloma idahoense (WA‐STR), Pristinicola hemphilli (OR‐STR, WA‐SEN), Radiodiscus abietum (SEN). In addition, morphologically distinct specimens of Oreohelix were collected near the Wenaha River, and they are suspected to represent a new species. This survey was a follow‐up effort to snail surveys conducted by Sarina Jepsen and Tom Burke in the Fall of 2010 (Jepsen et al. 2011). The Fall 2010 surveyors suspected that some snail species may not have been encountered because there had not been enough precipitation at the time of the surveys to bring some species out of aestivation. They recommended repeating the surveys at many of the same sites in the spring. The Spring 2012 surveys were more effective at encountering the target and other special status snail species than the Fall 2010 surveys. Future snail survey work is recommended on BLM land along the Wenaha River, BLM land along the North Fork John Day River, and in Hells Canyon. To the best of the authors’ knowledge, these areas have not been well surveyed for snails and they are within or close to the suspected ranges for many special status snail species. In addition, the authors recommend conducting a genetic analysis of Oreohelix in the Blue Mountains to determine whether the morphologically distinct individuals found along the Wenaha River represent a new species. Survey Protocol Site Selection We reviewed sites surveyed in the fall of 2010 (Jepsen et al. 2011) and selected sites to revisit that were snail species rich, including sites along the South Fork Walla Walla River, the South Fork Umatilla River, and Lime Hill. We also examined the historical collection localities and the suspected distributions of each of the four target species. We consulted with Tom Burke, a 4 knowledgeable malacologist, about suggested areas to survey. We reviewed the habitat requirements of each of the target species (summarized in Foltz 2009) and queried Forest Service and BLM biologists about habitat features – such as talus slopes and basalt outcrops – that are thought to be associated with some of our target snail species. In order to obtain a better search image for the habitat that might support Megomphix lutarius, we visited a historic collection site for this species “about 5 miles above Weston, a few feet from the dry bed of Pine Creek” (Baker 1932, Figure 1). We did not survey for the species at this site, because it is currently on private land. After completing the background work described above, we added sites along the North Fork Umatilla River, the North Fork John Day River, the Wenaha River, and Joseph Creek to our list of sites to survey. Table 1. Historic collection localities for Oreohelix strigosa delicata in Oregon and Washington. State County Location Date Reference Walla Walla River Canyon above Milton, four OR Umatilla 9 July 1946 Pilsbry 1939 miles up the south fork (type locality) Walla Walla River Canyon above Milton, two to OR Umatilla 9 July 1946 Pilsbry 1939 three miles up the south fork (type locality) Table 2. Historic collection localities for Megomphix lutarius in Oregon and Washington. State County Location Date Reference Valley of Pine Creek, 0.5‐10 Academy of Natural Sciences OR Umatilla mi above Weston, 640‐915 1931 Philadelphia online database m alt. Academy of Natural Sciences OR Umatilla Weston 1931 Philadelphia online database pre‐1914 (no date, but California Academy of OR Umatilla Weston collected by H. Hemphill, Science online database who died in 1914) Figure 1. Photos of the Pine Creek about 5 miles above the town of Weston, OR, the likely location where Megomphix lutarius was collected in 1931. 5 Table 3. Historic collection localities for Polygyrella polygyrella in Oregon and Washington. State County Location Date Reference east of Milton, 2 to 3 miles up the north fork of the OR Umatilla 1931 ANSP online database Walla Walla River Talus on S. side of Rogersburg Road. Grande Ronde 19 Aug Deixis Collection WA Asotin R.‐Snake R.‐Columbia R., SW of Rogersburg (town 1989 and 2 2009 site) (Asotin County), at RM 2.1 Sept 1990 Talus on W. side of Snake River Road and Snake 1 Sept Deixis Collection WA Asotin River at RM 168.3 (Asotin County), N. of Heller Bar 1990 2009 Leonard 2009 pers. Tributary of NF Touchet River, FS Rd 64 20.5 mi S of 20 June WA Columbia comm. with S. F. US 12, Umatilla National Forest 2009 Jordan 26 Sept WA Columbia Touchet River, site 2‐1 Jepsen et al. 2011 2010 Walla WA 15 miles east of Walla Walla Duncan 2008 Walla Table 4. Historic collection locality for Allogona ptychophora solida in Oregon and Washington. State County Location Date Reference 1.2 miles south of Asotin, 5 Oct Burke, T. 2009. Personal communication with WA Asotin above Snake River Rd. 1986 Sarah Foltz. Survey Period The recommended survey period for these snail species is from April to May, after spring melt‐ out, or from September to November, as fall‐winter rains occur, but before first heavy freeze (Frest & Johannes 1995). We chose to survey during the spring time period, as a follow up to previous surveys for three of the four target species that occurred in the Fall. We 6 communicated with local Forest Service and BLM biologists to make sure snow had melted at each of our target survey areas. Sampling Methodology We used the species specific survey protocol for each of the four target species from Foltz (2009), which includes identification features, distribution, Federal Units where the species is suspected or documented, areas where surveys are recommended, habitat where surveys should take place, commonly associated mollusk species, and general survey methods and instructions for each species. We also consulted Duncan et al. 2003 (survey methodology for information on collecting and storing voucher specimens, and followed the protocol described in section II.B.2.b. Survey Methods for Talus, Rock and Cave Habitat). While driving or hiking in each selected region, we looked for key habitat features utilized by the four target species. When we spotted a key habitat feature, such as a talus slope, basalt outcrop, or area with persistently high humidity (such as a seep on a rock wall), we began to survey for mollusks by turning over and examining the undersides of rocks and/or dead wood. We frequently stopped to survey at sites that had springs or other water sources, especially if rock outcrops or talus piles were also present at the site. Hand rakes were used to move talus and aid in searching. The total time spent at each site varied based on our findings. If we spent 15‐20 minutes searching for mollusks and failed to find additional species during that time period, we left the site and moved on to another site. A Garmin Rino GPS unit was used to obtain geographic coordinates for each site surveyed. Methodology for collecting voucher specimens When mollusks were observed, shells and live specimens were collected in small vials or, in the case of slugs, in recycled yogurt containers and kept in a cooler with ice. In the evening, small snails were placed directly in 70% ethanol, whereas large snails were drowned overnight in water, which caused them to emerge from their shells, then stored in 70% ethanol. After the field surveys, all collected mollusks were sent to Tom Burke for identification. Tom Burke reported that some of the large snails apparently retracted into their shells after being placed in alcohol, suggesting that placement in water overnight was not effective at killing the specimens. Thus, it was difficult, and in some cases impossible, to examine soft tissues of these specimens for identification purposes.