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Irvine, CA, United States

Ellstrand N.C.,University of California at Riverside | Heredia S.M.,University of California at Riverside | Leak-Garcia J.A.,University of California at Riverside | Heraty J.M.,University of California at Riverside | And 4 more authors.
Evolutionary Applications | Year: 2010

The evolution of problematic plants, both weeds and invasives, is a topic of increasing interest. Plants that have evolved from domesticated ancestors have certain advantages for study. Because of their economic importance, domesticated plants are generally well-characterized and readily available for ecogenetic comparison with their wild descendants. Thus, the evolutionary history of crop descendants has the potential to be reconstructed in some detail. Furthermore, growing crop progenitors with their problematic descendants in a common environment allows for the identification of significant evolutionary differences that correlate with weediness or invasiveness. We sought well-established examples of invasives and weeds for which genetic and/or ethnobotanical evidence has confirmed their evolution from domesticates. We found surprisingly few cases, only 13. We examine our list for generalizations and then some selected cases to reveal how plant pests have evolved from domesticates. Despite their potential utility, crop descendants remain underexploited for evolutionary study. Promising evolutionary research opportunities for these systems are abundant and worthy of pursuit. © 2010 Blackwell Publishing Ltd.

McBride M.F.,University of Melbourne | Wilson K.A.,University of Queensland | Burger J.,Irvine Ranch Conservancy | Fang Y.-C.,Irvine Ranch Conservancy | And 5 more authors.
Ecological Modelling | Year: 2010

Ecological restoration is an increasingly important tool for managing and improving highly degraded or altered environments. Faced with a large number of sites or ecosystems to restore, and a diverse array of restoration approaches, investments in ecological restoration must be prioritized. Nevertheless, there are relatively few examples of the systematic prioritization of restoration actions. The development of a general theory for ecological restoration that is sufficiently sophisticated and robust to account for the inherent complexity of restoration planning, and yet is flexible and adaptable to ensure applicability to a diverse array of restoration problems is needed. In this paper we draw on principles from systematic conservation planning to explicitly formulate the 'restoration prioritization problem'. We develop a generalized theory for static and dynamic restoration planning problems, and illustrate how the basic problem formulation can be expanded to allow for many factors characteristic of restoration problems, including spatial dependencies, the possibility of restoration failure, and the choice of multiple restoration techniques. We illustrate the applicability of our generic problem definition by applying it to a case study - restoration prioritization on The Irvine Ranch Natural Landmark in Southern California. Through this case study we illustrate how the definition of the general restoration problem can be extended to account for the specific constraints and considerations of an on-the-ground restoration problem. © 2010 Elsevier B.V.

Wilson K.A.,University of Queensland | Lulow M.,Irvine Ranch Conservancy | Burger J.,Irvine Ranch Conservancy | Fang Y.-C.,Irvine Ranch Conservancy | And 5 more authors.
Journal of Applied Ecology | Year: 2011

1. In general, conservation seeks to prevent further habitat loss but in many cases there is a need to reverse habitat degradation. Restoration of habitat is necessary to achieve biodiversity conservation goals but often it is a costly and time-intensive process. Prioritization of where and when habitat is restored can help to ensure the cost-effective delivery of desired outcomes. 2. We develop a restoration prioritization decision support tool to identify the combination of restoration sites and the schedule for their implementation most likely to deliver the greatest utility for a fixed budget and operational constraints. We use a case study to apply our prioritization approach in order to illustrate the data that can be employed to parameterise the analysis and the outputs that are able to inform restoration planning. We compare restoration schedules under alternative utility functions to demonstrate trade-offs associated with different objectives, assumptions and preferences for particular outcomes. 3. Our prioritization approach is spatially and temporally explicit and accounts for the costs and benefits of restoration, the likelihood of restoration success, the probability of stochastic events, feedbacks, time lags and spatial connectivity. 4. Through collaboration with restoration practitioners we derive quantitative and spatially explicit data on each site requiring restoration. We determine the relative priority for restoring each site and develop a restoration schedule over 20years. 5. Our results showed that after 20years a little over a half of the sites requiring restoration are likely be successfully restored, while the total expenditure at our site will be c. US$13·7million - almost the entire budget of $14million. 6. Synthesis and applications. Our restoration prioritization approach provides a schedule for where and when restoration should occur, and also provides operational guidance and support for cost-effective restoration planning such as informing the likely total cost of restoration. © 2011 The Authors. Journal of Applied Ecology © 2011 British Ecological Society.

Hamilton R.A.,Hamilton Biological Inc. | Burger J.C.,Irvine Ranch Conservancy | Anon S.H.,Irvine Ranch Conservancy
Western Birds | Year: 2012

Responding to studies identifying an apparent lack of suitable natural nesting sites for the Cactus Wren (Campylorhynchus brunneicapillus) in coastal southern California, we designed "cactus-like" nesting structures and nest boxes (1) to determine whether this wren would use such structures or boxes and (2) to assess the efficacy of different construction designs. Out of 32 nest boxes deployed, two supported Cactus Wren nests that successfully fledged young-one in 2010 and another in a different location in 2011. In fall 2010, another box in yet a third location was used for a brood nest. In contrast, we observed no nesting in the 13 cactus-like structures over three years of study. Our results provide "proof of concept" that Cactus Wrens will select and successfully use nest boxes even in areas of mature cactus scrub. Furthermore, all three boxes used by Cactus Wrens were mounted in a tilted position, in which the nest box was angled up to 45°, rather than level. In the summer of 2011, we retrieved the artificial structures and weathering nest boxes and mounted 21 new boxes in the tilted position and with a level floor inserted to prevent eggs from falling into the bottom. We expect that this and future experiments will evaluate the potential conservation value of nest boxes for Cactus Wrens in areas recovering from wildfire and at sites of cactus restoration.

Kimball S.,University of California at Irvine | Lulow M.,University of California at Irvine | Sorenson Q.,Irvine Ranch Conservancy | Balazs K.,University of California at Irvine | And 4 more authors.
Restoration Ecology | Year: 2015

Ecological restoration is a multibillion dollar industry critical for improving degraded habitat. However, most restoration is conducted without clearly defined success measures or analysis of costs. Outcomes are influenced by environmental conditions that vary across space and time, yet such variation is rarely considered in restoration planning. Here, we present a cost-effectiveness analysis of terrestrial restoration methods to determine how practitioners may restore the highest native plant cover per dollar spent. We recorded costs of 120 distinct methods and described success in terms of native versus non-native plant germination, growth, cover, and density. We assessed effectiveness using a basic, commonly used metric (% native plant cover) and developed an index of cost-effectiveness (% native cover per dollar spent on restoration). We then evaluated success of multiple methods, given environmental variation across topography and multiple years, and found that the most successful method for restoring high native plant cover is often different from the method that results in the largest area restored per dollar expended, given fixed mitigation budgets. Based on our results, we developed decision-making trees to guide practitioners through established phases of restoration-site preparation, seeding and planting, and maintenance. We also highlight where additional research could inform restoration practice, such as improved seasonal weather forecasts optimizing allocation of funds in time or valuation practices that include costs of specific outcomes in the collection of in lieu fees. © 2015 Society for Ecological Restoration.

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