Euphydryas Editha Taylori Research Articles

Upland prairie adaptive management staged‐scale restoration practices for native plant and endangered butterfly reintroduction

Abstract The present practice insight derives from land manager requests to document current on‐site activity and provides a management planning reference for restoration on Violet Prairie. Start‐up restoration initiates from trial‐and‐error adaptive management practices in the Puget Sound region of western Washington, USA. Treatments used focus on the implementation of staged‐scale restoration. Preparation intends to meet reintroduction goals of establishing a native plant community that could potentially support the threatened endemic Castilleja levisecta (golden paintbrush). Reintroduction of the associated native plant community provides habitat for endangered Euphydryas editha taylori (Taylor's checkerspot butterfly). Known conventional agricultural use coupled to fire suppression since the 1800s altered regional prairie lands to an unfavourable state for native plant species. Local native prairie soil types were favoured for growing conventional grasses and exotic forb species common to grazing pastures. Land abandonment and degradation has lengthened the time of disturbance and complicated restoring to a generalized reference point prior to settlement. Persistent exotic species, encroaching housing development, coniferous forest and recent wildfire complicate converting back to native prairie. Threatened and endangered species and their habitat are targeted in a trial‐and‐error process of staged‐scale adaptive management within the goal of whole ecosystem and connectivity restoration. Land managers focus on exotics removal and intensive native reseeding while restoring the use of prescribed burning as a maintenance tool. Embedded monitoring and observation advises where future practices need to be adapted by focusing on treatments and outcomes. Past land use practices replaced native soil seed banks with exotic seed banks that further distort reference proxies. Unknowns interrupt the current implementation additionally to soil conversion issues, while short‐term adaptive management methods initiate conversion back to native prairie. Species reintroduction choices to develop community structure are complicated by the fact that historical reference point species may be missing altogether from existing native communities. An unanswered outcome of the restoration process is determining which set of treatments best prepares soil for the desired native plant community.

Instar‐specific effects of host plants on survival of endangered butterfly larvae

1. Outcomes for butterfly conservation can hinge on interactions with host plants during early larval instars. Ontogenetic changes in larvae may cause predictors of survival to shift quickly over time.2. Survival from instar to instar was measured for an endangered oligophagous butterfly,Euphydryas edithassp.taylori(Taylor's checkerspot), which was experimentally released in the field on three host plants:Castilleja levisecta,Castilleja hispida, andPlantago lanceolata. Survival rates were quantified, from hatching to the second instar, from the second to the third instar, and from the third to the fourth instar.3. This study tested whether host plant characteristics (degree of senescence and anthocyanin pigmentation) affected survival during each instar; the effects of oviposition timing and larval group size on survival were also tested, as these vary by group and could affect outcomes for larvae differently on different hosts.4. Survival rates depended on the host species being consumed, mostly because of a disparity in survival during the transition from the second to the third instar. Survival was lowest onC. levisecta, intermediate onC. hispida, and highest onP. lanceolata.5. Plant senescence, oviposition timing, and group size were predictors of survival, but their relevance depended on both the host plant being used and the instar being considered.6. Host plant suitability can vary strongly both within and among species, changing quickly with caterpillar ontogeny during early instars.

Rare species and aliens: reconsidering non‐native plants in the management of natural areas

AbstractNatural areas are often managed for the protection of native species and ecosystems. The presence of non‐native species is generally perceived to run counter to these objectives; thus, they are often controlled or tolerated but rarely deliberately favored. We suggest greater emphasis be placed on the role species play in ecological settings regardless of their origin, recognizing that only some non‐native plants are invasive, that the risk of causing ecological harm varies considerably, and that distributions will change as species migrate in response to climate change. We sense a disparity between the way this topic—conservation value of non‐native species—is addressed in the literature and how it is applied in management of natural areas. To encourage more discussion and consideration of appropriate roles for non‐natives in natural areas management, we present five case studies illustrating their value in the conservation of rare and endangered species, including Taylor's checkerspot and island marble butterflies, southwestern willow flycatcher, and the giant kangaroo rat. Our last case study describes a proposed conservation action for the rare Brewer spruce—that of assisted colonization, itself the creation of a non‐native for conservation purposes. Although we support continued avoidance of introducing invasives and a cautious treatment of non‐natives, we encourage those with responsibility for natural areas management to not only evaluate the threats posed by non‐natives, but to also consider their potential benefits in relation to management objectives.

Oviposition Preference of Endangered Taylor's Checkerspot Butterflies (Euphydryas editha taylori) Using Native and Non-Native Hosts

Abstract The federally endangered Taylor's checkerspot (Euphydryas editha taylori) is an increasingly rare prairie butterfly in the Willamette Valley-Puget Trough-Georgia Basin ecoregional complex. Since the arrival of European settlers, several factors have reduced available native host plants for E. e. taylori larvae. The most common host is now Plantago lanceolata, an exotic species long prevalent in the area. Local biologists have observed that the known native hosts have low available biomass relative to P. lanceolata, and may senesce too early to support the animals throughout their entire larval feeding cycle. Federally threatened Castilleja levisecta, which often grows larger and persists longer than currently-utilized native hosts, may have been important historically but its range does not now overlap with E. e. taylori. Previous work with other E. editha ssp. has shown that oviposition preference is: 1) heritable and may provide clues to which hosts were used historically, and 2) has been corre...

Intertwined Fates: Opportunities and Challenges in the Linked Recovery of Two Rare Species

ABSTRACT: Rare species recovery presents several challenges for conservation managers, particularly when listed species interact with one another. We present a case study involving two such species: golden paintbrush (Castilleja levisecta) and Taylor's checkerspot butterfly (Euphydryas editha taylori), both of which occur in lowland prairies in the Puget Sound region and are federally protected (threatened and endangered, respectively). These two species occupy some of the same sites, and golden paintbrush likely historically served as a larval food plant for Taylor's checkerspot. Managers working to recover these species have encountered a number of challenges and opportunities—recovery efforts for one species may have no effect, positive effects, or negative effects on the other. Furthermore, sometimes rapid recovery actions are necessary on shorter time scales than those at which research typically occurs, and must proceed in spite of significant knowledge gaps. Here we share how our growing understand...

Conservation Projects in Prison: The Case for Engaging Incarcerated Populations in Conservation and Science

The pace of habitat destruction and loss of biological diversity globally exceeds the current capacity of societies to restore functioning ecosystems. Working with prison systems to engage inmates in habitat conservation and ecological science is an innovative approach to increase our ability to reestablish habitat and at-risk species, while simultaneously providing people in custody with opportunities for reciprocal restoration, education, therapeutic activities, safer conditions, and lower costs of imprisonment. We present the benefits of working with prisons to conduct habitat conservation through nursery production of plants and captive rearing of animals, combined with educational experiences, and provide an overview of the Sustainability in Prisons Project Network. Examples of projects with prisons in Washington and Oregon include nursery production of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis) for restoring habitat of the greater sage-grouse (Centrocercus urophasianus), nursery production of early blue violet (Viola adunca) to support conservation of threatened Oregon silverspot butterflies (Speyeria zerene hippolyta), captive rearing programs for Oregon spotted frogs (Rana pretiosa) and endangered Taylor's checkerspot butterflies (Euphydryas editha taylori), and nursery production of over 60 plant species for restoration of native prairies. Including incarcerated people in conservation and science could tap into the positive potential of over 2 million inmates at over 4000 prisons and jails in the United States and create new partnerships to support large-scale habitat restoration and ecological research.

Influence of thermal conditions on habitat use by a rare spring-emerging butterfly Euphydryas editha taylori

We may expect butterflies as ectotherms to have particularly active life-history stages that occur in the warmest and lightest times of the year; however, there are temperate species that are active when climatic conditions seem unfavourable and photoperiod short, such as the Taylor's checkerspot (Euphydryas editha taylori). For such species, studies suggest that even subtle changes to microclimate can potentially impact populations. Thus, understanding how in situ variations in microclimate influence the Taylor's checkerspot butterfly could provide much needed insights into more effective management. We conducted a series of surveys that explored (i) adult habitat use, (ii) final instar larval distribution and (iii) adult movement up to and across site boundaries at two sites in Oregon, USA, in 2010 and 2011. We found that in situ habitat use by the Taylor's checkerspot butterfly was strongly influenced by microclimate. Both adult activities and final instar larvae distribution were clustered within the warmest areas of the sites. Moreover, adults did not use up to 59% and larva up to 90% of their sites, despite vegetation structure and composition being uniform. More specifically, butterfly habitat use increased with increasing ground temperatures, and we found that areas with the highest ground temperatures were more exposed to direct sunlight. Similarly, we found that butterflies tended to only move through sunlit site boundaries. We conclude that the Taylor's checkerspot is sensitive to changes in its thermal environment at fine spatial scales. Our results highlight the importance of microclimate as an indicator of habitat quality, and establishing the thermal criteria in which species of concern exists may provide valuable insights into the implications of climate change.

Behavioral consequences of exotic host plant adoption and the differing roles of male harassment on female movement in two checkerspot butterflies

Herbivorous insects may evolve convergent behaviors when independent adoption of a shared novel host plant places populations in environmental conditions that diverge from the ancestral state. We investigated the behavioral consequences of adopting Plantago lanceolata, an exotic species to North America, in populations of Euphydryas p. phaeton and Euphydryas editha taylori, on the east and west coasts of North America. Activity budgets and short-term movements suggested that innate species tendencies exert a greater impact on behavior than adoption of the same exotic host plant. However, female E. phaeton from a Plantago-dependent population spent more time inspecting host plants than females from a population dependent on the native host plant, Chelone glabra. Both checkerspot species had similar diffusion coefficients (D) regardless of host plant association. But, E. e. taylori step-lengths appeared bimodal and power law distributed while E. phaeton step-lengths were unimodal and best fit by an exponential distribution. We attribute this bimodal step-length distribution to the persistent harassment of courting males which induces a “long-distance” evasive flight in otherwise sedentary E. e. taylori females. In contrast, the longer distance step-lengths of E. phaeton were associated with the inspection of oviposition plants. These two checkerspot species appear to move greater distances across the reproductive landscape with contrasting motivational states that could lead to either intimate mapping (E. phaeton) or coarse mapping (E. e. taylori) of host resources.

Pyrenopeziza plantaginis new to North America.

Pyrenopeziza plantaginis is reported from leaves of Plantago lanceolata from remnant native prairie sites in Benton Co., Oregon which harbor the endangered Taylor's checkerspot. The butterfly uses P. lanceolata as a pre-diapause larval host. The fungus is associated with a leaf blight of P. lanceolata and may impair restoration of populations of Taylor's checkerspot.

Conservation of Prairie-Oak Butterflies in Oregon, Washington, and British Columbia

Abstract Prairie-oak butterfly species in the Willamette Valley-Puget Trough-Georgia Basin (WPG) ecosystem have declined dramatically due to widespread habitat degradation and loss of prairie-oak ecosystems in the region. Conservation of prairie-oak butterflies offers unique opportunities and special challenges. Here we provide an overview of butterfly conservation in WPG prairies. We begin with a review of the status of at-risk butterfly species in the region, an introduction to five species that are the focus of current conservation efforts: Fender's blue (Icaricia icarioides fenderi), Taylor's checkerspot (Euphydryas editha taylori), mardon skipper (Polites mardon), island marble (Euchloe ausonides insulanus), and Oregon silverspot (Speyeria zerene hippolyta), and a brief review of 10 additional at-risk butterfly species in the ecoregion. We follow with a discussion of three key threats (habitat loss and fragmentation, invasive species, and lack of appropriate disturbance) and four dominant management ...

Selectively eliminating and conserving exotic plants to save an endangered butterfly from local extinction

AbstractRare butterfly conservation requires understanding of butterfly interactions with the resource conditions that influence population growth. Exotic plant invasions can reduce butterfly population size and growth by displacing key resources, degrading habitat conditions and directly impacting fitness, but exotic plants may also be incorporated into native butterfly diets, rendering practicing conservation biologists a choice between exotic plant control and butterfly population persistence. Euphydryas editha taylori (Nymphalidae), a candidate endangered butterfly species in the Pacific Northwest of North America, switched from an unknown native larval host plant to become entirely dependent on an exotic larval host Plantago lanceolata in extant western Oregon populations. Furthermore, the last Oregon butterfly populations are surrounded by two exotic grasses, Brachypodium sylvaticum and Festuca arundinacea, both of which can dominate remnant native prairies and degrade native grassland structural conditions. When given a choice of habitat conditions, E. e. taylori oviposited on larval host plants surrounded by increasing abundance of short‐statured native bunchgrasses and adult nectar resources, indicating that females select egg‐laying sites based on habitat conditions rather than just host plant presence. Both larval and adult resources substantially diminished with increasing cover of exotic grasses and were nearly absent when B. sylvaticum and F. arundinacea dominated. Butterfly resource loss with increasing exotic grass cover, the documentation of contemporary subpopulation extinction, current historic site conditions and grass invasion history in the Willamette Valley suggest that mass E. e. taylori extinction in western Oregon by the late 1970s was due to B. sylvaticum and F. arundinacea invasion. To prevent the extinction of E. e. taylori, land managers must accept that the anthropogenically mediated host switch to P. lanceolata must be conserved and that reintroductions/augmentation with a potential native host plant species is unlikely to be effective because larval development is timed to P. lanceolata growth.