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As habitat loss and fragmentation, urbanization, and global climate change accelerate, conservation of rare ecosystems increasingly relies on human intervention. However, any conservation strategy is vulnerable to unpredictable, catastrophic events. Whether active management increases or decreases a system's resilience to these events remains unknown. Following Hurricane Irma's landfall in our habitat restoration study sites, we found that rare ecosystems with active, human‐imposed management suffered less damage in a hurricane's path than unmanaged systems. At the center of Irma's landfall, we found Croton linearis' (a locally rare plant that is the sole host for two endangered butterfly species) survival and population growth rates in the year of the hurricane were higher in previously managed plots than in un‐managed controls. In the periphery of Irma's circulation, the effect of prior management was stronger than that of the hurricane. Maintaining the historical disturbance regime thus increased the resilience of the population to major hurricane disturbance. As climate change increases the probability and intensity of severe hurricanes, human management of disturbance‐adapted landscapes will become increasingly important for maintaining populations of threatened species in a storm's path. Doing nothing will accelerate extinction. [ABSTRACT FROM AUTHOR]

Abstract Substitute species (common species used to represent endangered species) are used to evaluate a range of conservation strategies globally. However, the effectiveness of this approach has not been empirically evaluated. We leveraged a large-scale habitat restoration experiment to test the validity of the substitute species concept. We selected a common butterfly, Satyrodes appalachia , that is on first inspection as near a substitute as possible - it is closely related to, overlaps in distribution, habitat requirements, host use, and life history with Neonympha mitchellii francisci , an endangered butterfly. We integrated small-scale measures of behavior, habitat preference, and demography of both species in our test, demonstrating that subtle differences between two species cause the substitute relationship to fail. Despite nearly identical habitat requirements, we found the endangered butterfly used different host plants, had higher larval survival in restored sites, and was found in more open habitat than the common butterfly. These differences added up to differences in abundances; the endangered species was more abundant than the common species in restored sites, the opposite was true in un-restored sites. Management decisions based on unvalidated substitute species run the risk of doing more harm than good for endangered species conservation. Instead, using experiments to evaluate a target species' response to management will result in effective recovery strategies. Highlights • Different responses to restoration from two similar butterflies reveal the limits of substitute species in conservation • Management decisions based on unvalidated substitutes likely do more harm than good for conservation • Best practice is to use carefully designed experiments to study endangered species directly [ABSTRACT FROM AUTHOR]

The article focuses on Polites mardon (P. mardon) which is grass skipper endemic to the Pacific Northwest of the U.S. Topics include overwintering of P. mardon as larvae in the wild and presence of larval shelters in the field; laying of eggs by female P. mardon in the grass without affixing to host plants; and behavior of P. mardon that reflects their sedentary nature in larval state.

The article focuses on species of the butterfly Polites mardon found in the Pacific Northwest of the U.S. It mentions decline in the population of P. mardon due to various environmental conditions like loss of grassland, montane meadow habitats because of forest succession and increase in invasive species. It highlights many studies over life history of P. mardon.

Habitat restoration frequently focuses on reaching an idealized steady state, but this is unrealistic for disturbance‐dependent ecosystems where temporal variability is inherent and habitat conditions are expected to fluctuate. Understanding the ways in which the outcomes of restoration change over time in disturbance‐dependent ecosystems can better inform adaptive management plans and increase the likelihood that restoration efforts will be effective. We conducted a decade‐long restoration experiment to test how restoration efforts to increase disturbance levels impact habitat quality and populations of an endangered butterfly over time. We show that changes in plant communities as a response to disturbance vary depending on time since restoration, with target host plants initially increasing and peaking several years postrestoration but then declining. In the absence of further disturbance, butterfly population sizes follow a similar pattern, with population declines concurrent with declines in host plants. Due to this nonlinear response, management actions within disturbance‐dependent ecosystems need to include long‐term monitoring in order to accurately capture changes in habitat response, as well as active, adaptive planning that shifts according to current system stability. Restoration efforts within these dynamic habitats are more likely to succeed when temporal variability is explicitly tracked and multiple cycles of restoration are considered as part of management actions. [ABSTRACT FROM AUTHOR]

Citizen science harnesses the power of nonscientist observations, often resulting in a vast network of data. Such projects have potential to democratize science by involving the public. Yet participants are mostly white, affluent, and well-educated, participants that contribute data from their residence or places they frequent. The geography of the United States is heavily segregated along lines of race and class. Using a Census Tract-level hurdle model, we test the relationship between the locations of the rain gauges from the citizen science project Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS) with continuous variables for percent non-Hispanic white and median household income. We find whiter and more affluent Census Tracts are significantly more likely to have a rain gauge. The highly localized nature of precipitation combined with the uneven geography of storm-water infrastructure make data missing from citizen science projects like CoCoRaHS of vital importance to the project's goals. We warn that scientific knowledge created from citizen science projects may produce scientific knowledge in service of wealthy, whiter communities at the expense of both communities of color and low-income communities. [ABSTRACT FROM AUTHOR]

Changes in phenology are a common response to climate change, but their impact on population dynamics is often ambiguous and at‐risk species are omitted from most analyses.We assessed the relationship between change in abundance and change in phenology for 114 butterfly populations of 31 at‐risk species from five families in 10 US states. We used data from Pollard‐walk and similar monitoring programmes for which count data were collected on multiple occasions per year. We also collected information from managers on site‐level management interventions.To estimate abundance, we first fit separate smoothing splines for each species at each site. Yearly abundance was estimated as the area under the activity curve for that year, and from this, we estimated abundance trends over the period for which we had population data. Phenological shifts were measured as the changes in median activity date, beginning of flight season, duration of flight season and phenological constancy (negative of the magnitude of trends in median activity date). We also evaluated the association of ecological traits (voltinism, diet breadth, position within geographic range, ecoregion, overwintering stage and seasonality) and management (proportion of years with interventions) with trends in abundance and in phenology.Across all populations, the estimated trend in abundance was −0.085, equivalent to an 8.1% decline/year. Positive trends in abundance were associated with smaller shifts in the median flight date (higher constancy). We also found strong associations between trends in abundance and management interventions, with increased management associated with increasing abundance trends. In general, ecological traits were not strongly associated with trends in phenology or trends in abundance.Synthesis and applications: Populations with less phenological constancy are more likely to be rapidly declining and populations with more frequent management interventions are increasing. These results suggest that one key outcome of management interventions may be to mitigate some of the impacts of climate change, which in turn may contribute to higher population growth. These results also imply that managers may need to alter the timing of appropriate management to synchronize with activities of at‐risk species as species shift their phenology. [ABSTRACT FROM AUTHOR]

The number of insect species at risk of population decline and extinction is increasing rapidly. Yet we know almost nothing about the ecology of these species, except for at-risk butterflies. A growing body of literature shows how butterfly vital rates, including demography and movement, are essential for guiding conservation and recovery. History has shown us that without these data, conservation decisions often weaken, rather than enhance, population viability. This is especially true in changing landscapes. We review knowledge of vital rates across all at-risk butterflies. We have information on movement for 17 of 283 butterfly species and information on demography for 19 species. We find that habitat-specific movement behavior is key to understanding how to connect populations, and habitat-specific demography is central to managing habitats. Methods and analyses worked out for butterflies can provide a scaffold around which to build studies for the conservation of other at-risk insects. [ABSTRACT FROM AUTHOR]