Martes Caurina) Distribution Study on the Olympic Peninsula, Washington

Interagency Pacific Marten (Martes caurina) Distribution Study On the Olympic Peninsula, Washington

Final Interagency Special Status/Sensitive Species (ISSSSP) Report for the Field Seasons of June 30–October 4, 2017, and May 1–October 31, 2018

Betsy Howell USDA Forest Service; Olympic National Forest 295142 Hwy 101 S., Quilcene, WA [email protected]

Katie Moriarty National Council for Air and Stream Improvement (NCASI) 227 NW 3rd St, Corvallis, OR 97330 [email protected]

Robert Long Woodland Park Zoo 5500 Phinney Ave. N, Seattle, WA 98103 [email protected]

Paula MacKay Independent Contractor Woodland Park Zoo 5500 Phinney Ave. N, Seattle, WA 98103 [email protected]

Patti Happe USDI National Park Service, Olympic National Park 600 E. Park Ave., Port Angeles, WA 98362 [email protected]

Kurt Jenkins U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center 600 E. Park Ave., Port Angeles, WA 98362 [email protected]

Keith Aubry USDA Forest Service; Pacific Northwest Research Station 3625 93rd Ave SW, Olympia, WA 98512 [email protected]

Pacific Marten photographed in Olympic National Park, December 7, 2017

Introduction

The Pacific marten (Martes caurina) is a medium-sized, semi-arboreal carnivore in the family Mustelidae (weasels) that once occurred throughout coniferous forests in the Pacific coastal states (Zielinski et al. 2001). Historically, Pacific marten populations in Washington occurred primarily in 2 disjunct areas, the Cascade Range and the coastal mountains, which were separated by apparently unsuitable habitat in the Puget Trough (Dalquest 1948). Cascade populations, which appear to be relatively stable (Zielinski et al. 2001), occur primarily in true fir forests at high elevations where deep snow accumulates during winter. In contrast, coastal marten populations historically occupied a much broader elevational range, including low- elevation coniferous forest habitats near sea level (Bailey 1936; Hagmeier 1956).

In 2001, a summary of historical and recent observations of Pacific martens in coastal areas of the Pacific States indicated that martens were apparently absent from much of their historical range along the California coast and ‘also may have declined on the Olympic Peninsula of Washington’ (Zielinski et al. 2001). These results indicated a need to augment inventories of Pacific martens to better evaluate their current population status. In northern California and Oregon, the coastal subspecies of the Pacific marten (Martes caurina humboldtensis) was petitioned for listing as Federally Threatened in 2010. After the U.S. Fish & Wildlife Service issued a 12-month finding in 2015 that listing the subspecies was not warranted, the Center for Biological Diversity subsequently filed a court challenge. In response, the agency issued a proposed rule in October 2018 to list the coastal distinct population segment of the Pacific marten as threatened (USDI 2018). The enduring lack of reliable information on the current distribution and status of coastal marten populations in Washington State, however, represents a significant impediment to making informed decisions about their conservation. This concern has also elevated the coastal marten to an ISSSSP Top 10% Priority Species for the Olympic National Forest (ONF) on Washington’s Olympic Peninsula.

The primary objective of this ongoing study is to determine if the Pacific marten still occurs as a viable population on the Olympic Peninsula in Washington, and to investigate the underlying causes for its low population numbers and/or restricted distribution. Here, we report the preliminary results of surveys conducted during 2017 and 2018 that built upon previously reported surveys conducted during the winter of 2015-2016 and summer of 2016 (Moriarty et al. 2016). The purpose of the 2017-2018 surveys was to conduct additional surveys for martens at high-elevation areas using 2 new techniques: 1) long-term, over-winter (fall-spring) camera surveys utilizing automated scent dispensers, and 2) scat-detection dogs deployed in the summer. We hoped that both techniques would have greater success detecting martens than our previous efforts using only camera surveys conducted at high-elevations during summer (Moriarty et al. 2016). As in our earlier efforts, we also hoped to obtain detections of other carnivores, including the fisher (Pekania pennanti), a Forest Service TRACS (Terrestrial Restoration and Conservation Strategy) Priority Species for the Pacific Northwest Coast Ecoregion, and western spotted skunk (Spilogale gracilis), a Washington Department of Fish & Wildlife Species of Greatest Conservation Need.

Background

Historical baselines depicting former distribution patterns and abundance of martens are sparsely documented on the Olympic Peninsula. In his early assessment of mammal populations of Olympic National Park and vicinity, Victor Scheffer concluded that martens were widespread on the Peninsula in the 1940s inhabiting coniferous forests ‘from salt water to timberline’ ….. ‘wherever flying squirrels, red squirrels, chipmunks, mice, and other food species are to be found’ (Scheffer 1949). Trapping records suggest that martens were relatively common at that time—in the 1940s, 83 martens were legally trapped in Clallam, Jefferson, and Mason counties, 3 of the 4 counties that comprise the Olympic Peninsula (cited in Zielinski et al. 2001). However, marten trapping records on the Olympic Peninsula declined precipitously after that time; only 2 martens were harvested in the 1950s and 9 in the 1960s. Surprisingly, 4 martens were reportedly trapped in Pacific County (located south of the Olympic Peninsula along the coast) in the 1970s, but no martens have been legally trapped on the Peninsula or along the southwest coast of Washington since that time. As of 2001, coastal marten populations in all 3 of the Pacific states had declined or been extirpated (Zielinski et al. 2001).

Thus, in low- to mid-elevation forests on the Olympic Peninsula, martens may have been extirpated by overtrapping, which adversely affected marten and fisher populations throughout the western states (e.g., Dixon 1925, Dalquest 1948, Yocom 1974). However, high-elevation forests on the Peninsula may have provided a refuge from trapping, due to their remoteness, relative inaccessibility, and protection in Olympic National Park or wilderness areas of Olympic National Forest. Although extensive modification of lower elevation forests does not appear to provide a barrier to movements by reintroduced fishers (Lewis et al. 2016), martens generally avoid young forests and, typically, do not cross openings > 50 m wide (Cushman et al. 2011, Moriarty et al. 2015). Avoidance of young forests, along with more limited dispersal capabilities compared to fishers, may provide a partial explanation for why martens have not recolonized lower elevation forests from higher elevation refuges.

From 1991 to 2016, 7 separate remote-camera surveys were conducted in coastal habitats and mid- to high-elevation coniferous forests on the Olympic Peninsula to document the presence of carnivores, especially martens and fishers. Two verifiable detections of Pacific martens were obtained from these 7 survey efforts (Figure 1).

Summer 1991: Remote-camera surveys were conducted in the Cascade Range, Puget Trough, and Olympic Peninsula. Thirty-nine photos (out of 260 taken) were judged at the time to be martens with only 1 from the Peninsula (Jones and Raphael 1991). We have subsequently reexamined this photo in detail, however, and do not consider it to be diagnostic of a marten; rather, it appears to be a long-tailed weasel (Mustela frenata).

March–October 1992: Approximately 50 remote cameras were deployed in the Hoh, Dosewallips, Duckabush, Hamma Hamma, and Gold Creek drainages on the Olympic Peninsula; 1 photo of a marten was reportedly taken near the Dosewallips River (Sheets 1993). However, this photograph is not available for examination and cannot be verified.

Winters of 2001–2002 and 2002–2003: Extensive camera surveys targeting forest carnivores were conducted in ONP. Among the 1,270 photos that were obtained during this effort, none were of martens (Happe et al. 2005).

Summers 2006–2008: Remote camera and track-plate surveys were conducted in the riparian zone of the Elwha River in ONP to document mesocarnivore distributions before dam removal. No martens were detected in over 1,500 camera-trap nights and 8,000 trackplate-nights of effort (Jenkins et al. 2015).

Summers 2009–2015: Remote-camera surveys were conducted on ONF and ONP (in addition to State, Tribal and private lands) to monitor the distribution of fishers reintroduced to the Olympic Peninsula from 2008 to 2010. One marten was detected in August 2015 in the Upper Hoh watershed during ~16,380 camera-trap nights (Figure 1).

Winters 2013 and 2014: Camera surveys targeting martens along the east side of the Olympic Mountains were conducted in collaboration with a group of citizen-scientists. Efforts were focused near the locations of recent reliable records of martens obtained through 2014 (Figure 2). No martens were detected during ~1,400 camera-trap nights.

Winter 2015–2016 and Summer 2016: The most recent previous survey efforts targeting Pacific martens on the Olympic Peninsula were focused primarily at mid- to high- elevations in the areas where previous records were obtained (Moriarty et al. 2016). We also surveyed the coastal strip of ONP, based on findings from the Coast Range in Oregon where recent survey work had documented the presence of martens <1 km from the ocean (Moriarty et al. 2016). We surveyed with 108 camera stations (54 sample units) during the winter of 2015–2016 in the coastal strip of ONP, and 85 camera stations (43 sample units) during the summer at high elevations in ONP and ONF in 2016 (Figure 1, pink triangles). In 17,897 camera nights, 1 marten was detected in the Upper Hoh watershed in August 2016.

Other studies have demonstrated that when martens are present, they have a very high probability of detection at baited camera stations during the winter (Zielinski et al. 2015; R. Long, unpubl. data). This was verified during the winters of 2001–2003, when a region-wide forest carnivore inventory was conducted in Mount Rainier, North Cascades, and Olympic National Parks simultaneously. Although no martens were detected in the Olympic Mountains, they were commonly detected in the Cascade Range (Christopherson et al. 2005). Considering these 7 survey efforts collectively, the detections of martens at only 2 stations in 2015 and 2016 (both in the Upper Hoh and possibly of the same animal; Figure 1) raises substantial concerns about the conservation status of martens on the Olympic Peninsula.

Figure 1—Remote-camera surveys conducted from 1991 to 2016, and the 2 marten detections that were obtained in the upper Hoh watershed of ONP during those surveys.

In addition to the 2 recent detections of Pacific martens from the surveys described above, a photo of a marten in the western coastal region was obtained opportunistically in 1968, and several others were obtained opportunistically on the east side of the Olympic Peninsula from the late-1970s to 2008, indicating that the species still occurs on the Peninsula (Figure 2), but is restricted in distribution to a few small areas. Two of these opportunistic detections have only recently been rediscovered and so have not appeared in earlier reports on Olympic martens: 1) the 1968 photograph found in January 2019 by a Washington Department of Transportation employee, and 2) the late-1970s record of a marten that was killed on Highway 101 near Mt. Walker on ONF and subsequently collected and skinned by a local trapper, which was rediscovered in November 2017 (K. Aubry, unpubl. data). In 1988, a marten was photographed at close range in The Brothers Wilderness (K. Aubry, unpubl. data). In 1990, on 2 different occasions, researchers reported live-trapping and releasing a marten near the Dosewallips River during a northern spotted owl (Strix occidentalis caurina) prey-base study (B. Biswell, PNW Research Station, pers. comm.). Although neither of these specimens was collected and this record is not verifiable by photographic evidence, the researchers were experienced mammalogists and had the animals “in hand,” giving strong credence to these records. In 2008, a dead juvenile female marten was found on the trail to Mt. Rose in the southeast corner of the Olympic Peninsula on ONF; the specimen was deposited in the Burke Museum at the University of Washington in Seattle (UWBM 81064). This record is particularly important, because it demonstrates that martens were present and reproducing on the Peninsula as recently as 2008; due to the current isolation of the Peninsula, the juvenile female marten was unlikely to represent a dispersal event from elsewhere (e.g., the Cascade Range). Finally, in June 2015, a photograph of a marten was taken by a rock climber at the summit of Mt. Cruiser on the border of ONP and ONF (Figures 2 and 3). In total, there have been only 8 reliable records of Pacific martens on the Olympic Peninsula between the late 1970s and 2016.

Figure 2—Highly reliable records (9) of Pacific martens on the Olympic Peninsula, Washington, 1968–2016 (Note: the 1990 Dosewallips location includes 2 reliable records.)

Figure 3—Pacific marten on Mt. Cruiser, June 2015. Photo by Shemuel Harding

In summary, extensive survey efforts have been directed at martens and fishers in the Olympic Mountains during the last decade. The scarcity of verifiable records of martens obtained during these surveys demonstrates that there is likely no more than a few small, potentially isolated subpopulations, and that considerable uncertainty exists regarding the future viability of the Pacific marten on the Olympic Peninsula.

Study Area and Methods

Because all detections of martens since 2008 have been in mid- to high-elevation areas, we focused our efforts in 2017 and 2018 near those records. The elevation ranges sampled correspond largely with the mountain hemlock (Tsuga mertensiana), subalpine fir (Abies lasiocarpa), and subalpine parkland zones near or above timberline (Gavin and Brubaker 2015).

Although the surveys we conducted in 2016 were the most extensive and rigorous to date in high-elevation areas, there were limits on how long stations could remain on the landscape at higher elevations and be checked safely by field crews; thus, the crews were limited to accessing areas during snow-free months when work could be done safely. Consequently, in 2017, we decided to use new technology, which involved over-winter sampling, using automated long- term scent dispensers (R. Long and others, unpubl. data) with remote cameras at 6 sites. Each dispenser, attached to a tree approximately 12 feet above the ground, consists of a small pump controlled by an ultra-low power processor that is programmed to release 3 ml of liquid scent lure each day. In this way, remote camera stations can remain functional in areas where snow and winter working conditions prevent regular checking of sites. These sites, checked during the spring and summer of 2018, served as tests of how well the dispensers would work in the Olympic Mountains, where they had not been tested before. In late summer 2018, we installed 12 more stations with over-winter, long-term scent dispensers in ONP, each paired with baited and lured stations, and also used scat-detection dogs to search for marten scats along trails in ONF near historical marten locations.

2017:

We installed 6 over-winter survey stations from June to August, with funding provided by the carnivore program in Region 6 of the Forest Service. Four stations were located on ONF, 2 on Mt. Rose near the 2008 marten detection, and 2 at Mildred Lakes near the 2015 Mt. Cruiser detection (Figure 4). Each of these stations comprised 1 remote camera, a long-term lure dispenser, and a cow femur suspended by a cable beneath the dispenser to hold and help disperse the scent. In August, 2 stations were placed in the upper Hoh drainage in ONP, 1 near the 2015 marten detection (fisher monitoring study) and another near the 2016 marten detection (marten high-density study). These stations each included the bone and dispenser and 2 cameras (1 Reconyx and 1 Bushnell), both aimed on the dispenser and bone, as well as a cubby box containing hair-snaring devices to collect DNA. Prior to the onset of winter, the stations in the Hoh drainage and at Mt. Rose were checked during the fall to verify that they were operational.

Figure 4—Remote camera stations with long-term, over-winter scent dispensers, installed summer 2017.

2018:

Installing new cameras and scent dispensers:

In 2018, we deployed cameras and over-winter scent dispensers in high-elevation areas that had not been sampled during previous surveys. Altogether, 24 cameras and 12 scent dispensers (2 cameras per dispenser) were installed in 3 areas in ONP: High Divide, between the Sol Duc and Hoh watersheds; Dodger Point, above the Elwha River; and Honeymoon Meadows, in the headwaters of the Quinault River (Figure 5). We deployed 12 sample units, resulting in 12 dispenser stations with bones, and 12 stations with a film canister/sponge/lure combination referred to as "random" because they were offset 100-300 m in a random direction from a paired camera/dispenser station. These sites will be checked during summer 2019.

Figure 5—Locations of cameras and overwinter scent dispensers at High Divide, Dodger Point, and Honeymoon Meadows.

Scat-detection dogs:

Scat-detection dog teams from the University of Washington’s Conservation Canines program surveyed 22 trail systems in ONF in August and October (Figure 6). Each dog was accompanied by a trained handler, who encouraged the dog to course back and forth through the forest as they proceeded along the trail. When the dog picked up on a target scent, it would trace the scent to its source and indicate the find by sitting or lying down. In addition to marten scats, dogs were trained to locate fisher, mountain lion (Puma concolor), and bobcat (Lynx rufus) scats.

Figure 6—Tracks showing scat-detection dog surveys conducted in August and October 2018. All routes were surveyed during August 2018, except 3 routes in the Hamma Hamma watershed (Lena Lakes, Putvin, and Mildred Lakes) which were surveyed in October because proximity to the Maple Fire limited access during August.

Results

Checks of the six 2017 cameras:

Mt. Rose

The scent dispensers and cameras at both Mt. Rose stations were still functioning on May 8, 2018. No martens had been detected during the previous winter and spring. We replaced the dispensers with new bags of lure and changed out the memory cards in the cameras. The cameras were refreshed and left in place for another year.

Mildred Lakes

These stations were checked on July 6 and 7, 2018. Again, no martens had been detected, though 2 different fishers (1 with a radio collar and 1 without) were detected, 1 at each station. The dispenser’s pump system at 1 station had stopped working, while the other pump system continued to function, though bags of lure mixture in both dispensers were empty. Both cameras were still functioning. These stations were removed.

Upper Hoh drainage These 2 stations were checked in late August 2018. Both scent dispensers were still functioning. At 1 site, the Reconyx camera had apparently stopped working for much of the survey, but the Bushnell camera functioned the entire survey period. At the other site, the Reconyx camera had been investigated by a bear, causing it to point in a suboptimal direction. The Bushnell camera remained functional at that site. We obtained marten photos at both of these stations, dated September 27, 2017, and December 7, 2017 (Figure 7). This brings the total number of the most recent detections of martens to 4, all in the upper Hoh watershed.

New bags of lure were installed into the dispensers and reset for another year. Both stations were checked again in early October 2018; no additional martens were detected on that check, but 1 station recorded a western spotted skunk.

From these six stations deployed from summer 2017 to spring or summer 2018, we identified 20 wildlife species (Table 1). Both Hoh cameras documented martens, the Mildred Lakes cameras each recorded an individual fisher (1 with a collar and 1 without), and the Mt. Rose cameras did not record any mustelids.

Figure 7—Marten detections in the upper Hoh watershed of ONP from 2015 to 2017.

Table 1—Deployment and check dates and wildlife species detected at 6 camera stations deployed with long-term scent dispensers over winter in the Olympic Mountains, 2017-2018.

SPECIES DETECTED

)

) )

)

Date )

detected )

) (marten Date Date and fisher

Tamias spp.) Tamias sabrinus)Glaucomys douglasii Tamiasciurus americanus Lepus hemionusOdocoileus Cervuselaphus Lynxrufus latransCanis Ursusamericanus gracilis Spilogale erminea Mustela caurina Martes Pekaniapennanti Dendragapusobscurus Cyanocittastelleri canadensis Perisoreus Ixoreusnaevius Turdusmigratorius

Station installed checked only) Chipmunk ( squirrel flying Northern ( squirrel Douglas's ( Mouse hare Snowshoe ( deer Black-tailed ( elk Roosevelt ( roosevelti Bobcat ( Coyote ( bear Black ( skunk spotted Western ( Ermine ( weasel Long-tailed frenataMustela marten Pacific ( Fisher ( grouse Sooty ( Woodpecker jay Steller's ( jay Gray ( thrush Varied ( robin American ( Glacier Meadows (upper Hoh) 8/29/17 9/12/17 X X X 8/23/18 12/7/2017 X X X X X X X 10/4/18 X X X Martin Creek (upper Hoh) 8/29/17 9/12/17 X X 8/23/18 9/27/2017 X X X X X X X X X X X X X 10/4/18 X Mt. Rose 1 6/30/17 10/4/17 X X X 5/8/18 X X X X Mt. Rose 2 6/30/17 5/8/18 X X X X X Mildred Lakes 3 7/6/17 7/12/18 5/15/2018 X X X X X Mildred Lakes 4 7/7/17 7/12/18 5/8/2018 X X X X X

Scat-detection dogs:

We collected 48 scats from 15 of the 22 trails surveyed using scat-detection dogs (Figure 8). Of these 48, DNA obtained from 40 was suitable to confirm species identification. Five non-target species were detected, including coyote (Canis latrans), black bear (Ursus americanus), long- tailed weasel (Mustela frenata), Roosevelt elk (Cervus elaphus roosevelti), and domestic dog. No martens were detected and bobcats were the most commonly detected animal (Table 2).

Table 2—Scats (33) identified to wild carnivore species collected during scat-detection surveys in the Olympic Mountains, summer 2018.

Species Number of samples Bobcat 24 Mountain lion 3 Fisher 2 Coyote 2 Black bear 1 Long-tailed 1 weasel

Two issues arose during the scat-detection dog surveys, including teams surveying in non-target areas and collecting scats contaminated with domestic dog DNA. In the first instance, 1 team accidentally surveyed in ONP along the Dosewallips Road, as well as on a portion of the Mt. Jupiter trail that is on private land. Once it was determined that they had entered the national park, where dogs are not allowed, except for trailheads and designated areas, the team left ONP and returned to the national forest. The error on the Mt. Jupiter trail was not realized until after the field season; however, there are plans to redo this trail next year. Regarding the samples containing domestic dog DNA, the source, whether from the dog surveyor or from external contamination in the surrounding environment, is unknown.

Additionally, 3 scats contained fisher DNA, but 1 sample had only enough fisher DNA to amplify once and, after multiple attempts, did not produce enough DNA to confirm the species. This scat was noted as being “very large almost big enough around to be a bear,” so it’s possible that another carnivore ate a fisher, but this is only speculation.

Figure 8—Final genetic species identifications for scats collected by scat-detection dogs (“ND” refers to an inconclusive determination).

Discussion

Based on historical records and recent survey work, Pacific martens appear to be very limited in distribution throughout most of their former range on the Olympic Peninsula in Washington. We detected martens at 2 stations during our 2017 overwinter surveys that were located approximately 4-km apart in the upper Hoh River drainage in ONP. It is possible these detections represent a single individual, and could even be the same marten that was detected in 2015 and 2016. Nevertheless, there are only 11 highly reliable marten detections on the Olympic Peninsula since 1968 (i.e., during the last 50 years). However, there is direct evidence of the presence of only 2 or 3 martens on the Olympic Peninsula from all sources since 2013—1 or 2 martens in the upper Hoh drainage, and 1 marten near Mt. Cruiser in 2015. Our survey efforts build upon previous broad-scale surveys by the National Park Service, their collaborators, and the Forest Service (Figure 1). The paucity of observations of martens in both low- and high-elevation habitats, where the species is commonly observed elsewhere, raises substantial concerns about the long-term viability of Pacific martens on the Olympic Peninsula.

We suspect that the number of martens on the Olympic Peninsula is extremely low, and that they may exist as 1 or a few small and isolated subpopulations; if true, such isolation would increase their risk of extirpation. It is possible that 1 such subpopulation exists in the upper Hoh drainage, as we have now documented martens there for 3 years in a row. Potential threats to remnant populations include demographic risks associated with small population size, which may be exacerbated by environmental influences. Martens are typically associated with montane environments where deep winter snow accumulates, which may provide seasonal refugia from predators (Moriarty et al. 2015). However, climatic changes may increasingly threaten the viability of this species (Dawson et al. 2011; Pauli et al. 2013). In addition, there may be other factors contributing to the decline of martens on the Olympic Peninsula, including competition with other carnivores, predation, historical overtrapping, and/or disease (e.g., Holm et al. 2016). Further, the use of anticoagulant poisons to control rodents has recently emerged as a significant concern for non-target wildlife, including forest carnivores (Gabriel et al. 2012). However, none of these hypothetical causes for the decline and scarcity of Pacific martens on the Olympic Peninsula is testable without a much better understanding of the distribution and status of remnant populations.

Since our last ISSSSP report in December 2016, we obtained results from a phylogeographic analysis of marten populations in the Pacific states using complete mitochondrial genomes (mitomes; Schwartz and Pilgrim 2016). These analyses included a large sample of martens from all other portions of their range in the Pacific states, as well as 7 historical marten samples from the Olympic Peninsula, dating from 1886 to 1902 that were obtained from the Smithsonian National Museum, and 1 contemporary genetic sample (the Mt. Rose specimen found dead in 2008). Several findings from this study provided new insights about the evolutionary history of Pacific martens on the Olympic Peninsula: (1) contemporary and historical specimens from the Peninsula belong to the same genetic subclade, indicating that the Mt. Rose animal is a remnant of the historical population and not a recent immigrant; (2) contrary to our prediction, martens on the Olympic Peninsula do not belong to the same genetic subclade as the coastal Pacific martens in Oregon and California, which are currently of significant conservation concern (e.g., California Fish and Wildlife Commission 2018, Linnell et al. 2018, USFWS 2018). This suggests that the Columbia River provides a strong barrier to gene flow among coastal Pacific marten populations. Pacific marten samples from the Olympic Peninsula were more closely aligned with samples from the western portion of the Cascade Range in Washington, indicating that Pacific martens colonized the Olympic Peninsula from the Cascade Range relatively recently. Thus, there may once have been greater connectivity between coastal and montane (Cascade) marten populations in Washington than there was between coastal and montane populations in Oregon and California. Accordingly, marten populations in the Cascade Range of Washington, which appear to be relatively abundant and well distributed, could provide a source population for the augmentation of Pacific marten populations on the Olympic Peninsula, should such actions be deemed appropriate by wildlife managers and conservationists.

Martens on the Olympic Peninsula appear to occur at critically low population densities, with all reports of the species in the past 20 years occurring in Olympic National Park or wilderness areas on Olympic National Forest. In 2019, we will retrieve all cameras and dispensers, analyze the data, and determine the next steps in the project. Depending on results in 2019, we may aim to conduct additional intensive, focused surveys at specific locations, such as installing multiple

cameras in a grid pattern in the upper Hoh drainage with hair snares to obtain genetic material and determine if a small population persists in that region. Our hope would be to better quantify the geographic extent and genetic diversity of the current population, and to determine what conservation actions should be taken to maintain a viable population. Such a focused effort could be implemented for a few weeks during the summer months (in order to obtain quality genetic material), or with camera stations and long-term, over-winter scent dispensers installed in select areas. Such efforts would help managers make informed decisions for marten conservation in the region, while also promoting the broader goals of maintaining biological diversity and contributing to species recovery on public lands.

Acknowledgments

Survey efforts were funded by the Interagency Special Status/Sensitive Species Program (ISSSSP) and Pacific Northwest Research Station and in collaboration with the College of Forestry at Oregon State University. Considerable aid with field logistics, vehicles, housing, and equipment was provided by the USDA Forest Service, Olympic National Forest, Woodland Park Zoo, and USDI National Park Service, Olympic National Park. Extreme thanks go to field crew members, Matt Delheimer, Brent Barry, Alyssa Roddy, Liz Graham, Annie Doss, Tom Kay, Kelly Atkins, and Scott Gremel for their dedication to this project and their outstanding work in the field. Use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

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