Meek M.H.,University of California at Davis |
Wells C.,University of California at Davis |
Tomalty K.M.,University of California at Davis |
Ashander J.,University of California at Davis |
And 14 more authors.
Biological Conservation | Year: 2015
The potential for extirpation of extremely small populations (ESPs) is high due to their vulnerability to demographic and environmental stochasticity and negative impacts of human activity. We argue that conservation actions that could aid ESPs are sometimes delayed because of a fear of failure. In human psychology, the fear of failure is composed of several distinct cognitive elements, including "uncertainty about the future" and "upsetting important others." Uncertainty about the future is often driven by information obstacles in conservation: information is either not easily shared among practitioners or information is lacking. Whereas, fear of upsetting important others can be due to apprehension about angering constituents, peers, funders, and other stakeholders. We present several ways to address these fears in hopes of improving the conservation process. We describe methods for increased information sharing and improved decision-making in the face of uncertainty, and recommend a shift in focus to cooperative actions and improving methods for evaluating success. Our hope is that by tackling stumbling blocks due to the apprehension of failure, conservation and management organizations can take steps to move from fear to action. © 2015 Elsevier Ltd.
Hasselquist E.M.,Center for Natural Lands Management |
Hasselquist E.M.,Umeå University |
Hasselquist N.J.,University of California at Riverside |
Hasselquist N.J.,Swedish University of Agricultural Sciences |
And 2 more authors.
Restoration Ecology | Year: 2013
Invasive non-native plants pose a ubiquitous threat to native plant communities and have been blamed for the decline of many endangered species. Endangered species legislation provides legal instruments for protection, but identifying a general method for protecting endangered species by managing non-natives is confounded by multiple factors. We compared non-native management methods aimed at increasing populations of an endangered forb, Ambrosia pumila, and associated native plants. We compared the effects of a grass-specific herbicide (Fusilade II), hand-pulling, and mowing in two degraded coastal sage scrub sites in southern California, U.S.A. At both sites, hand-pulling had the greatest effect on non-native cover, and correspondingly resulted in the greatest increase in A. pumila stems. Fusilade II application also led to an increase in A. pumila, but was not as effective in controlling non-native plants as hand-pulling and its effect varied with the dominant non-native species. Mowing was not effective at promoting A. pumila, and its effect on non-native cover seemed to be related to rainfall patterns. Although some methods increased A. pumila, none of our treatments simultaneously increased cover of other native plants. Hand-pulling, the most effective treatment, is labor intensive and thus only feasible at small spatial scales. At larger scales, managers should take an experimental approach to identifying the most appropriate method because this can vary depending on the specific management objective (endangered species or whole native community), the dominant non-natives, yearly variation in weather, and the timing of treatment application. © 2012 Society for Ecological Restoration.
Dunwiddie P.W.,Center for Natural Lands Management |
Dunwiddie P.W.,University of Washington |
Haan N.L.,University of Washington |
Bakker J.D.,University of Washington |
And 2 more authors.
Natural Areas Journal | Year: 2016
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 understanding of the complex ecology of these species has given rise to large-scale management questions and conflicts, and outline the strategies we are using to navigate these challenges. Our approach has included convening periodic workshops with experts on both species; designing and implementing research studies to fill knowledge gaps about the two species' relationship; and identifying "no regrets" actions that can be taken to benefit one or both species with minimal risk in the face of uncertainty. While the details of this case study are highly specific, the lessons can be applied to other systems with interacting listed species.
Dunwiddie P.W.,Center for Natural Lands Management |
Alverson E.R.,501 Irving Rd. |
Martin R.A.,Center for Natural Lands Management |
Gilbert R.,Fish and Wildlife Program
Northwest Science | Year: 2014
Although it is well documented that the vast majority of native prairies in western Washington have disappeared, it is less clear to what extent the remaining fragments have been modified by the loss of native taxa. In this study, we focus on one group of plants-native annuals-that are notably lacking in prairies today. Based on current and historical records, we compiled a list of 190 native herbaceous plant taxa (species, subspecies, and varieties) with high or moderate fidelity to prairie and oak habitats that have been recorded in upland prairies in the South Puget Sound region. Eighty (42%) of these are annuals, a proportion that is considerably higher than what occurs in these prairies today (average 18%). In addition, most native annuals (75) are forbs. These data suggest that in the past, native annual forbs may have comprised a significantly greater proportion of the diversity in the prairies. Although it is impossible to determine how widespread these species were historically, several measures suggest significant declines have occurred. Of the 80 total native annuals observed, 39% have not been recorded in recent inventories of the floras in any prairies in the region, and another 21% are known from only one site. Data from recently burned prairies suggest that both cover and species richness of annuals may double after a single fire. To avoid further loss of native annuals, we urge the inclusion of species from this functional group in future prairie restoration in this region. © 2014 by the Northwest Scientific Association. All rights reserved.
Hamman S.T.,University of Texas at Austin |
Hamman S.T.,Center for Natural Lands Management |
Hawkes C.V.,University of Texas at Austin
Restoration Ecology | Year: 2013
The restoration of disturbed ecosystems is challenging and often unsuccessful, particularly when non-native plants are abundant. Ecosystem restoration may be hindered by the effects of non-native plants on soil biogeochemical characteristics and microbial communities that persist even after plants are removed. To examine the importance of soil legacy effects, we used experimental restorations of Florida shrubland habitat that had been degraded by the introduction of non-native grasses coupled with either mechanical disturbance or pasture conversion. We removed non-native grasses and inoculated soils with native microbial communities at each degraded site, then examined how habitat structure, soil nitrogen, soil microbial abundances, and native seed germination responded over two years compared to undisturbed native sites. Grass removal treatments effectively restored some aspects of native habitat structure, including decreased exotic grass cover, increased bare ground, and reduced litter cover. Soil fungal abundance was also somewhat restored by grass removals, but soil algal abundance was unaffected. In addition, grass removal and microbial inoculation improved seed germination rates in degraded sites, but these remained quite low compared to native sites. High soil nitrogen persisted throughout the experiment regardless of treatment. Many treatment effects were site-specific, however, with legacies in the more degraded vegetation type tending to be more difficult to overcome. These results support the need for context-dependent restoration approaches and suggest that the degree of soil legacy effects may be a good indicator of restoration potential. © 2012 Society for Ecological Restoration International.
Adam Martin R.,Center for Natural Lands Management |
Hamman S.T.,Center for Natural Lands Management
Fire Ecology | Year: 2016
In the prairies of the Pacific Northwest, USA, fire has been reintroduced as a tool for reducing non-native, invasive plant cover and promoting the growth and establishment of native plant communities. Head fires and backing fires are the two primary ignition patterns used to complete most prescribed burns, but the relative effectiveness of these two methods on invasive plant control and native enhancement is unknown. A clear understanding of the relationship between fire behavior, fire severity, and fire effects on vegetation and how these metrics are affected by fire ignition patterns could help managers fine tune burn prescriptions to better achieve ecological objectives. We used observations from five prescribed burns in the south Puget Sound prairies of western Washington, USA, to evaluate the relationship between intensity, severity, and effects. Additionally, we collected data from two burns on how ignition patterns affected these relationships. We found a significant positive correlation between maximum surface temperature and fire severity, and a decline in perennial taxa with increasing fire severity. We also found that surface temperatures did not differ between ignition patterns, but a greater area burned at mod-erate severity in backing fires than in head fires. Ignition patterns differentiated plant communities by changing the number of species present within different life form categories. However, this response was contingent upon site history and pre-burn conditions. Native perennial forbs were associated with head fires in a site with high pre-existing native plant species richness. Native and exotic forbs were associated with backing fires at a site with low pre-existing native plant species richness. Thus, managers may want to consider ignition patterns when planning burn prescriptions in order to achieve particular ecological objectives. © 2016, Association for Fire Ecology. All rights reserved.
Hoeksema J.D.,University of Mississippi |
Hernandez J.V.,Colegio de Mexico |
Rogers D.L.,Center for Natural Lands Management |
Mendoza L.L.,Grupo Mexico |
And 2 more authors.
Ecology | Year: 2012
A key problem in evolutionary biology is to understand how multispecific networks are reshaped by evolutionary and coevolutionary processes as they spread across contrasting environments. To address this problem, we need studies that explicitly evaluate the multispecific guild structure of coevolutionary processes and some of their key outcomes such as local adaptation. We evaluated geographic variation in interactions between most extant native populations of Monterey pine (Pinus radiata) and the associated resistant-propagule community (RPC) of ectomycorrhizal (EM) fungi, using a reciprocal cross-inoculation experiment with all factorial combinations of plant genotypes and soils with fungal guilds from each population. Our results suggest that the pine populations have diverged in community composition of their RPC fungi, and have also diverged genetically in several traits related to interactions of seedlings with particular EM fungi, growth, and biomass allocation. Patterns of genetic variation among pine populations for compatibility with EM fungi differed for the three dominant species of EM fungi, suggesting that Monterey pines can evolve differently in their compatibility with different symbiont species. © 2012 by the Ecological Society of America.
Kronland W.J.,St. Cloud State University |
Kronland W.J.,Center for Natural Lands Management |
Restani M.,St. Cloud State University
Canadian Field-Naturalist | Year: 2011
We investigated how post-fire salvage logging of Ponderosa Pine (Pinus ponderosa) affected populations of cavity-nesting birds and small mammals in southeastern Montana in 2004 and 2005. We examined two salvage and two control plots with three point-count stations and one small mammal trap site randomly distributed across each plot. We used point counts and distance sampling methods to estimate density of cavity-nesting birds on each treatment. We also searched each plot for nests and used program MARK to construct a set of candidate models to investigate variations in nest survival related to treatment, year, and time. We used live traps arranged in webs centered on trapping sites and distance sampling methods to estimate small mammal density. Habitat characteristics were also quantified on each plot. Density of all cavity-nesting birds combined and of Hairy Woodpeckers (Picoides villosus) in particular were higher on the control than the salvage treatment. Density of large trees and abundance of active cavities were higher on the control treatment. Nest cavities on the salvage treatment were most often located in non-logged watersheds. Nest survival estimates were uniformly high, with only marginal variations attributed to treatment and year. Density of Deer Mice (Peromyscus maniculatus) was higher on the salvage than the control treatment, reflecting the amount of downed woody debris created during harvest.
Dunwiddie P.W.,Center for Natural Lands Management |
Martin R.A.,Center for Natural Lands Management
PLoS ONE | Year: 2016
Our study was undertaken to better understand how to increase the success rates of recovery plantings of a rare hemiparasite, golden paintbrush (Castilleja levisecta-Orobanchaceae). This species is endemic to westernWashington and Oregon, USA, and southwestern British Columbia, Canada. Over 5000 golden paintbrush plants were outplanted as plugs in 2007 at six different native prairie sites that were considered to be suitable habitat, based on general evaluations of vegetation and soil conditions. Outplantings were installed at regular intervals along transects up to 1 km long to include a range of conditions occurring at each site. All plantings were re-examined five years later. The patchy distribution of surviving plugs and new recruits within each reintroduction site suggested success is strongly influenced by microsite characteristics. Indicator species analysis of taxa growing in microsites around outplanted golden paintbrush identified species that were positively or negatively associated with paintbrush survival. Species such as Festuca roemeri, Eriophyllum lanatum, and Viola adunca were strong indicators at some sites; non-natives such as Hypochaeris radicata and Teesdalia nudicaulis tended to be frequent negative indicators. Overall, higher richness of native perennial forbs was strongly correlated with both survival and flowering of golden paintbrush, a pattern that may reflect interactions of this hemiparasite with the immediately surrounding plant community. Topographic position also influenced outcomes, with greater survival occurring on mounds and in swales, where soils generally were deeper. Our findings suggest that assessments of site suitability based on vegetation alone, and coarser, site-level assessments that do not characterize heterogeneity at the microsite scale, may not be strong predictors of restoration success over the longer term and in sites with variability in vegetation and soils. By identifying suitable microsites to focus rare species plantings, survival and efficiency may be significantly enhanced. © 2016 Dunwiddie, Martin. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Warrick G.D.,Center for Natural Lands Management
Southwestern Entomologist | Year: 2012
Annual pitfall trapping during a 10-year period indicated that outbreaks of false chinch bugs, Nysius raphanus Howard, occurred in 2005, 2009, and 2010 in the southern San Joaquin Valley of California. During these outbreaks, feeding by false chinch bugs appeared to cause widespread damage to rangeland shrubs. In 2009, a study was initiated to compare survival between shrubs infested by false chinch bugs and shrubs not infested. Fifty-one spiny saltbush, Atriplex spinifera J.F. Macbr. shrubs (<0.5 m in height) were selected, of which 26 had been infested and 25 had not been infested by false chinch bugs. Fifteen months later, survival of the false chinch bug-infested shrubs (22%) was significantly less (P < 0.001) than non-infested shrubs (96%). Results indicated that false chinch bugs (during outbreak years) can significantly depress survival of young saltbush shrubs.