Community Conservation for an Endangered Butterfly and Beyond

Who is the imperiled Klamath Mardon Skipper?

The Klamath Mardon skipper, temporary held for identification on a population survey day in 2021 nearby to Vesper Meadow Restoration Preserve. Picture by Vesper Meadow

The Mardon skipper, Polites mardon, is a rare butterfly found in scattered locations of Oregon and Washington. Mardon skippers are thought to have been more widespread and abundant prior to the past 150 years of human development, livestock grazing, fire suppression, and invasion of grassland habitat by native and non-native vegetation.

The subspecies, Klamath Mardon skipper is specific (aka endemic) to the Cascade Mountains in southern Oregon and is in perilous decline.

Most meadow protection/restoration projects implemented in the last decade were ineffective at stopping population declines. (Keller, 2023) Continued effects of water diversion and invasive grasses are compounded by the effects of climate change. Destructive activities like cattle grazing continue in Mardon Skipper habitat at the Medford District BLM. Cattle are an agent for stream incision, meadow dewatering, conifer encroachment, altering grass species and structure, eliminating nectaring flowers and eating the later stage larva which feed almost entirely on tender leaf tips and rest at the cut-off ends. (James, 2011)

Over the past two decades the populations at 93% of the fifteen Mardon Skipper sites on Medford District BLM-administered land in the Southern Oregon Cascades are shown to be in decline or have dropped to zero.

- Dianne Keller, Local Lepidopterist and Data Analyst, 2023

Without protection under the Endangered Species Act and the continued threats to their meadow habitats, it is up to grass-roots conservation and restoration efforts to save this species and their meadow habitats that we too rely on. These places are headwaters for our drinking water supply in the Rogue Valley, habitat for countless wildlife species like birds and elk, and serve as arefuge during this time of uncertain climate futures. That’s why we are launching:

Operation Mardon Meadows

Over the last few years, we have been working to grow partnership networks in southwest Oregon to address the needs of Mardon skippers and create a community that can effectively support their conservation:

This project involves a multipronged conservation strategy to monitor Poma populations and habitat, engage volunteers in conservation actions and habitat restoration, increase public awareness through education, art, and digital media. We will address the ongoing habitat degradation in the last two known meadows with viable populations of this southwest Oregon endemic species.

Research and Restoration:

  • Together with colleagues from The Understory Initiative, we are coordinating research efforts to understand the most influential habitat issues related to Mardon skipper decline. We will be working closely with them to generate a Mardon skipper habitat seed mix and restoring habitat that has been invaded by nonnative pasture grasses.

  • We are continuing restoration efforts for the wet meadow habitat necessary for Mardon skippers. With our partner, Project Beaver we are working toward a total of 75 beaver-based restoration structures in Latgawa and Spencer Creeks by the end of 2024. This partnership also extended to the neighboring BLM

Conservation Networking and Planning:

Local Biologist and Vesper Meadow Board Member, John Villella, has surveyed Klamath Mardon skipper populations in the southern Cascades for 8 years. Here he shows volunteers how to identify the Mardon skippers during a 2023 education program at Vesper Meadow.

  • Informed by regional and local reports and by conducting ongoing population surveys with local biologists we continue conversations with land managers like the local Bureau of Land Management and private landowners to create opportunities for conservation action.

Community Engagement and Education

  • We are engaging volunteers in meaning ways to protect intact Mardon skipper habitat, while restoring degraded habitat by working in partnership. Klamath-Siskiyou Wildland Center and Friends of the Cascade-Siskiyou National Monument - are supporting volunteer efforts to monitor sensitive meadows, as well as increase public education for this endangered species.

A call for community support! How you can help:

(1) Become a Mardon Meadow Monitor (July - October)

Be the eyes on the ground and ensure that Mardons have a safe home. Help monitor cattle enclosure fencing, cattle trespass, and assist with fence maintenance as needed. Involves driving on un-improved dirt roads, and walking through beautiful meadows near Howard Prairie Reservoir, OR. Fence repair experience preferred. Volunteers must provide their own transportation.

(2) Gift your support to this local conservation network

We have been growing the network of local private and Federal land managers, community organizations and volunteers, and some support from partners like the Bureau of Land Management and the Greenfield-Hartline Conservation Fund. With the skills of this network, and a little bit of funding we are going to conduct habitat research, conservation monitoring, and habitat restoration in 2024 and 2025. Help us boost our efforts and create a long-lasting strategy but supporting Operation Mardon Meadows:

A pregnant female Klamath Mardon Skipper takes a moment to fuel up on a Mule’s Ear flower at Vesper Meadow 2021. Picture by Vesper Meadow.

More on the Mardon:

Species Life History

Mardon skippers are part of the grass-feeding butterfly family, Hesperiidae, meaning the larvae feed exclusively on grass (aka graminoids). Mardon skippers are univoltine, completing one life cycle annually... meaning that individuals only live for one year! Individual adults live as butterflies between five and fourteen days. Adults do not all emerge on the same date, so the duration of the flight period at a given site depends, in part, on the population size at that site. Sites with large populations may have a flight period that extends for more than a month, whereas sites with small populations may have adults present for only ten or fewer days. Weather influences emergence and flight period duration. Wet or cold conditions delay emergence and conversely, warm, dry conditions promote earlier emergence (Potter et al. 2002).Adult mardon skippers eclose (emerge as adult butterflies) from late May to early July. Adults actively nectar throughout their flight period, and seek refuge from adverse weather low in the vegetative turf under grasses and forbs. Polites mardon seem to use a variety of flower species for nectar. The most common observations locally are American Bistort (Bistorta bistoides) and Meadow Penstemon (Penstemon sp.). Females lay eggs singly into graminoid bunches while perched (Beyer & Black 2007; Beyer & Schultz 2010). Eggs are thought to hatch within seven days (Black & Vaughan 2005), and larvae feed through the late summer into the fall. Female mardon skippers have been observed ovipositing on multiple graminoid species, indicating that the larvae may be generalists (Beyer & Schultz 2010). In Oregon it seems that Mardons prefer to lay their eggs on California oatgrass (Danthonia californica ) and Roemer’s fescue when available (Beyer & Black 2007). Variables such as grass structure, the surrounding plant structure, and tree shading also influence oviposition behavior (Henry & Schultz 2012).

It was previously believed that pupae hibernate through the winter (Potter et al. 1999; Dornfeld 1980; Newcomer 1966 in Potter et al. 1999), but preliminary studies of flagged mardon skipper larvae in the field by Beyer and Black (2007, see Figure 2) suggest that Cascade populations overwinter in the larval life stage, making them extremely vulnerable in the late summer and fall to trampling, cattle grazing, wildfire and other disturbances.

Local Conservation of the endemic Klamath Mardon Skipper

Mardon skipper conservation status

Mardon skippers are grassland and open meadow obligates endemic to the states of Washington, Oregon, and California. U.S. Federal Species of Concern, Washington State Endangered Species, Global Heritage Status Rank of G2G3, United States National Heritage Status Rank of N2N3, state rank of S1 in Washington and California, and S2 in Oregon, Forest Service Region 6 Sensitive Species, and a BLM Special Status Species. This butterfly was recently removed from the list of federal candidate species (United States Fish and Wildlife Service 2012).

The Klamath Mardon Skipper subspecies is only found in the Cascade-Siskiyou region of southwest Oregon and is facing steep declines. Without conservation action and protection for its meadow habitats, it is likely to go extinct.

Habitat changes

Historically the Southern Oregon Cascades, the Klamath Mardon Skipper (P. m. klamathensis) populations occurred in a small geographic area to the east of the city of Ashland. The story of their decline is a classic one of habitat degradation that coincides with settler land management. Like many places throughout the American west, a combination of water diversion, cattle grazing, invasive species, and now climate change have very quickly changed the landscape.

In the 1960’s there was a boom in Talent Irrigation District (TID) projects for storage reservoirs, diversion dams, canals and laterals to improve the water supply for the agricultural lands around the cities of Ashland and Talent. The TID network of canals drained surrounding wet meadows and their streams into two large reservoirs, Howard Prairie and Hyatt Lakes. In addition, the meadows populated by Mardon Skippers have been heavily grazed by livestock for over 100 years and impacted by logging activities for at least 70 years. (Schelz, 2022)

Surveying Mardon skippers
Starting in 2004 several years of surveying potential Mardon Skipper habitat resulted in the locating of twenty-three sites on public land with extant populations. Fifteen of those sites were on BLM-administered land. In 2016 a volunteer monitoring program was started by Steve Godwin. Annual monitoring occurs at most of the BLM sites, particularly those that continue to show Mardon Skipper activity.

The following discussion reviews the common threats to Mardon Skipper habitat identified in the Medford District BLM management plan (Black, 2010), then lists the plan’s recommended actions, followed by an evaluation of the effectiveness of completed restoration projects. It ends with four recommendations for improving Mardon Skipper habitat at the Medford District BLM sites.

Threats to Mardon Skippers and their Habitat Identified in the 2010 Management Plan

Within the BLM’s management plan a number of threats were identified, common to most sites were:

  • Cattle grazing

  • Off-road vehicle (ORV) traffic

  • Conifer encroachment

  • Logging (Black, 2010)

  • Additional threats identified in a Hunter Creek management plan also apply:

  • Small populations

  • Prescribed fire

  • Climate change (Hatfield, 2013)

Recommended Actions in the 2010 management plan included:

  • Build cattle exclosures

  • Use rotational cattle grazing

  • Restrict ORV access with signage and/or large boulders

  • Remove encroaching conifers

  • Maintain microclimate with buffer of large trees at meadow edge

  • Monitor sites for Mardon Skippers, larval host plant and high diversity of nectar plants

  • Actions taken by the Medford District BLM to ameliorate habitat threats

Further discussion of Effectiveness of Mardon Skipper Meadow Restoration Projects from Dianne Keller, 2023.

Some restoration efforts have been taken in the last decade, although have not been successfully implemented for Mardon skipper populations to recover. Active habitat degradation by cattle grazing needs to be stopped before any restoration efforts will be effective. Two BLM sites, PC 125 and PC 128, are good candidates for rescuing habitat by removing cattle grazing. All the other BLM sites are too degraded except for Buck Prairie. In 2010 Buck Prairie was reported as “extremely degraded” (Black, 2010). However, the meadow is showing good signs of recovery as a result of the retirement of the Keene Allotment and placement of boulders to restrict ORV traffic.

Cattle Exclosures

Fencing cattle out from a core area appears sensible, but it can be ineffective in stopping meadow degradation for two reasons:

1) If not maintained or monitored regularly posts or wires can droop or give out. Worse yet, fence wires can be intentionally cut or disconnected from their brackets and lowered to allow easy access for the cattle as in the situation at PC 125 summer of 2022. (Keller, October 2022)

2) Cattle exclosures eliminate cattle from only a small percentage of the meadow. Yet Mardon Skippers use habitat where it best meets their needs including outside fenced areas. Also, a meadow’s ecosystem functions as a whole; damage outside the fencing effects the quality of the habitat within the fencing, especially the meadow hydrology. 40% of the 3.75 ha of habitat used by the Mardon Skippers at PC 125 is outside the exclosure. 91% of the 2.58 ha of habitat used by the Mardon Skippers at PC128 is outside the exclosure.

Rotational Cattle Grazing

The Deadwood Grazing Allotment has been under a rotational cattle grazing regime at least since the renewal of the grazing permit in 2011. This system may have slowed down meadow degradation but has not stopped it. Drain off channels continue to incise, water table continues to drop, tall structure grasses continue to displace host grasses, and nectar sources continue to disappear.

For example, in the afternoon of June 24, 2022 the following habitat condition observations were made at PC 125:

The meadow all around the outside of the exclosure where at least 86 Mardon Skippers were utilizing the habitat showed heavy cattle usage evidenced by deep hoof prints in the mud, grazed vegetation and fresh, slippery and very malodourous excrement everywhere. Grasses and forbs were heavily grazed down to almost bare dirt around the outside of the fence line. The only nectaring flowers found outside the exclosure were a few bushes of the thick-leaved Wyethia. However, flowering plants were seen within the exclosure in wide variety and abundant numbers, providing ample nectaring sources. (Keller, August 2022)

Furthermore, the Howard Prairie Sentinel Site where cattle graze a few months each summer is another example. Norm Barret wrote in his 2019 annual report summary:

The plant community at Howard Prairie tends to be short and sparce. It, also, tends to have relatively few nectar sources during the flight period.” (Barrett, 2019)

It is known that grassland insects face some of the most severe declines in species diversity and total abundance, in part due to agriculture. Live-stock grazing is the largest agricultural land use. The literature is not clear, but a review of 115 studies that evaluated how cattle grazing affected butterflies found most of the studies outcomes depended heavily on the management chosen as well as environmental and evolutionary factors. (Bussan, 2022)

Mardon Skippers have specific needs and successful oviposition selection relies on an undamaged wet meadow system. (Beyer, 2010)

Removal of Encroaching Conifers

Meadow edge conifers can take seed and grow in an environment where the water table has dropped below the depth of their roots. Incised water courses and ditching drains the meadow of its spring run-off which, if it had soaked in, would have helped recharged the water table. Therefore, conifer encroachment is a symptom of hydrologic disfunction rather than a threat which can be eliminated by removal of trees. (Lubetkin, 2017)

Some at the BLM recognize this connection. “Trees are encroaching the meadows due to meadow dewatering caused by soil downcutting from a persistent history of cattle grazing”. (Schelz, 2022)

Meadow Dewatering

Stream incision is one factor that provides a strong meadow-drying effect. Incised streams that are disconnected from their water table provide a conduit to drain the surrounding area, thus lowering water table levels. (Schilling, 2004)

All sites where conifer encroachment is listed as a threat have a dropping water table, often from incised drainage channels originally created by excessive cattle grazing (PC 128) or ditching to drain the meadow early season to enable cattle grazing (MP 20.2).

The Mardon Skipper site most in need of a hydrologic fix is PC128. Two incised drainage channels start at the top of the meadow and run down on either side of the cattle exclosure. The vegetation in the exclosure is dried out by early June so 75-80% of the Mardon Skippers counted have been found at the foot of the meadow ¼ mile below the exclosure.

The Lidar image flown in August of 2015 (see previous page) show the water table near the surface only at the foot of the meadow. The accompanying photo was taken mid-June and shows how the water has puddled at the surface ¼ mile below the exclosure. The photo, also, illustrates the severity of damage by ORV traffic in Mardon Skipper habitat. No restoration project over the past decade has fixed either of these problems. Cattle grazing and ORV traffic remain the two biggest threats to this site.

A restoration technique to hold water in the meadow for the purpose of recharging the water table is needed. Low-tech process-based restoration (LT-PBR) is being implemented as a tool to slow erosion and build up incised banks. The Cascade-Siskiyou National Monument ecologist has been using these with good results. Three years ago stream flow obstruction was installed at Upper Parsnip Lake and “it helped tremendously with bringing the water level up.” In 2022 about 25 structures were put in Jenny Creek at Friedenburg Spring. Also, a bunch of willow trees were planted in Keene Creek below where the Parsnip Lakes drainage flows into Keene Creek. (Schelz, 2023)

Boulder Placement and/or Signage to control Off Road Vehicle Traffic

Placement of large boulders and signage to block ORV access to meadows has been effective in places which have narrow access points (Buck Prairie), a ditch between a well-traveled road and the meadow (PCT Meadow South) and when the meadow is too small to tear around in with an ORV (Little Hyatt Reservoir South).

An “Area Closed” sign at PC 128 was totally ineffective. The site is remote and no one is watching. Maintenance or rerouting of road 38-4E-8 as a means to control ORV traffic in the meadow below the exclosure at PC 128 has been considered by the BLM but found to be prohibitively expensive. An option could be to close the section of road from adjacent to the exclosure south to the foot of the meadow by the placement of boulders and tank traps. Ideal locations on this road to place obstructions are where there is no ORV work-arounds due to thick forest on both sides.

Reseeding Host Grasses and Nectar Plants

Reseeding of host grasses and nectaring plants is effective only if the meadow retains enough moisture through the summer to support the introduced wet meadow vegetation. Also, invasive grasses, in this case tall structure/thick thatched grasses originally introduced for cattle forage, can’t be allowed to take over.

About a decade ago the Pacific Crest Trail was rerouted around the meadow at the Hobart Peak West site. Included in the restoration was the reseeding of a damp upper corner of the meadow with a thick lawn-like mat of fescue. The rest of the site was and still is covered by tall structure, heavily thatched grasses. Neither the trail relocation or the reseeding succeeded in arresting the decline of Mardon Skippers. None have been seen at this site since 2009. Any reseeding project needs to take into account conditions of the whole habitat.

Small Populations

Small and fragmented populations are generally at greater risk of extinction from normal population fluctuations due to predation, disease, and changing food supply as well as from natural disasters such as droughts. Also, small populations are threatened with extinction from a loss of genetic variability and reduced fitness due to unavoidable inbreeding. (Shaffter, 1981)

Of the thirteen Medford District BLM sites whose numbers were low (1-29) in 2010, only two sites persist with around 6 to 12 skippers counted on Peak Day flight. No Mardon Skippers have been seen for several years in the remaining eleven.

Prescribed Fire

Perhaps the most destructive restoration project Mardon Skipper habitat is prescribed fire. “Burning of meadows with populations of butterflies, such as the Mardon Skipper, could extirpate the population if not done with careful consideration of butterfly behavior and life stage at time of burn, and knowledge of where the skipper population is distributed across the meadow.” (Hatfield, 2013) For more detailed information see the Coon Mountain Burn Site Occupancy Study 2009, 2010 and 2011. (Black, 2011)

To my knowledge prescribed fire has not been used by the Medford District BLM in meadows inhabited by Mardon Skippers. However, it was proposed as an alternative to herbicide application in the 2020 SSS Mardon Skipper Meadow Restoration Plan for the purpose of removing invasive grasses.

Climate Change

“The effects of global climate change are projected to include warming in the western mountains, causing snowpack and ice to melt earlier in the season, which will have an impact on mardon skipper sites as all are associated with permanent, ephemeral, or subsurface water. Although management at the population scale cannot directly address global climate change, providing quality habitat at multiple sites across the landscape may make this species more resilient to climate change impacts.” (Hatfiled, 2013)

At this writing PC 125 is the only site on BLM-administered land with a habitat of sufficient quality for maintaining resilience in the face of climate change. The current cattle grazing threat must be removed.

Recommendations

1) Remove the continued destruction of cattle grazing inside and outside the cattle exclosures by retiring the Deadwood Grazing Lease.

2) Re-establish the wet meadow habitat by restoring meadow hydrology.

3) Remove any invasive species, conifers, and woody shrubs not controlled by the return of a higher water table.

4) Re-establish host grasses and nectaring plants where conditions have been suitably restored for planting success.


References:

Barret, Norm, Unpublished 2019 Mardon skipper annual report summary to the Xerces Society, Independent Contractor, Shady Cove, OR.

Beyer, Loni J., Cheryl B. Schultz, Oviposition selection by rare grass skipper Polites mardon in montane habitats: Advancing ecological understanding to develop conservation strategies, Biological Conservation Journal 143 (2010) 862-872.

Black, S. H., L. Beyer, S Jepsen, et al., Management Plans for all Southern Oregon Cascade Mardon Skipper, October 2010.

Black, Scott H., Coon Mountain Burn Site Occupancy Study 2009, 2010 and 2011, Nov. 2011, ISSSSP website.

Bussan, S. K., Can cattle grazing benefit grassland butterflies?, Journal of Insect Conservation 26, 359-374, 2022.

Hatfield, Rich, Scott H. Black, Sarina Jepsen, Management Plans for all Southern Oregon Cascade Mardon Skipper sites on the Bureau of Land Management’s Hunter Creek Area of Critical Environmental Concern, March 2013.

James, David G., Nunnalle, David, Life Histories of Cascadia Butterflies, Oregon State university Press, 2011, p.188.

Keller, Dianne, PC 125 Habitat Condition Report: Deadwood Grazing Lease Guard Station Pasture, October 2022.

Keller, Dianne, Mardon Skipper Site Monitoring Report – 2022, August 2022.

Keller, Dianne, Mardon Skipper Population Trends, Feb. 2023.

Lubetkin, K. C., A. L. Westerling, L. M. Kueppers; Climate and Landscape Drive the Pace and Pattern of Conifer Encroachment into Subalpine Meadows, Ecological Applications Journal, May 8, 2017.

Schelz, Charles, Cascade-Siskiyou National Monument Pumpchance 125 Meadow Restoration Project, April 2022. Personal communication January 18, 2023.

Schilling, K. E., Zhang, Y. K., Drobney, P., Water Table Fluctuations near an Incised Creek, Walnut Creek, Iowa Journal of Hydrology, Volume 286, Issues 1-4, January 30, 2004, pp. 236-248.

Shaffter, M. L. 1981. Minimum Population Sizes for Species Conservation, BioScience 31:131-134.

Jeanine Moy