Native Community Members Research Articles

Trophic consequences of a biological invasion: do plant invasions increase predator abundance?

As invasive species become integrated into existing communities, they engage in a wide variety of trophic interactions with other community members. Many of these interactions are direct (e.g. predator–prey interactions or interference competition), but invasive species also can affect native community members indirectly, by influencing the abundances of intermediary species in trophic webs. Observational studies suggest that invasive plant species affect herbivorous arthropod communities and that these effects may flow up trophic webs to influence the abundance of predators. However, few studies have experimentally manipulated the presence of invasive plants to quantify the effects of plant invasion on higher trophic levels. Here, I use comparisons across sites that have or have not been invaded by the invasive plant Medicago polymorpha, combined with experimental removals of Medicago and insect herbivores, to investigate how a plant invasion affects the abundance of predators. Both manipulative and observational experiments showed that Medicago increased the abundance of the exotic herbivore Hypera and predatory spiders, suggesting positive bottom–up effects of plant invasions on higher trophic levels. Path analyses conducted on data from natural habitats revealed that Medicago primarily increased spider abundance through herbivore‐mediated indirect pathways. Specifically, Medicago density was positively correlated with the abundance of the dominant herbivore Hypera, and increased Hypera densities were correlated with increased spider abundance. Smaller‐scale experimental studies confirmed that Medicago may increase spider abundance through herbivore‐mediated indirect pathways, but also showed that the effects of Medicago varied across sites, including having no effect or having direct effects on spider abundance. If effects of invasive species commonly flow through trophic webs, then invasive species have the potential to affect numerous species throughout the community, especially those species whose dynamics are tightly connected to highly‐impacted community members through trophic linkages.

Environmental stress alters native-nonnative relationships at the community scale

The invasion of natural habitats by nonnative species is affected by both native biodiversity and environmental conditions; however few tests of facilitation between native community members and nonnative species have been conducted along disturbance and stress gradients. There is strong evidence for an increase in facilitation between native plant species with increasing levels of natural environmental stress, however it is unknown whether these same positive interactions occur between nonnative invaders and native communities. I investigated the effects of natural stress on community interactions between native heathland species and nonnative species with two field studies conducted at the landscape and community scale. At the landscape scale of investigation, nonnative species richness was positively related to native species richness. At the community level, nonnative invaders experienced facilitation with natives in the most stressful zones, whereas they experienced competition with native plants in the less stressful zones of the heathlands. Due to the observational nature of the landscape scale data, it is unclear whether nonnative diversity levels are responding positively to extrinsic factors or to native biodiversity. The experimental component of this research suggests that native community members may ameliorate stressful environmental conditions and facilitate invasion into high stress areas. I present a conceptual model which is a modification of the Shea and Chesson diversity-invasibility model and includes both facilitation as well as competition between the native community and nonnative invaders at the community level, summing to an overall positive relationship at the landscape scale.

Views of Biobanking Research Among Alaska Native People: The Role of Community Context

Views of Biobanking Research Among Alaska Native People:The Role of Community Context Vanessa Hiratsuka, MPH, Jennifer Brown, BA, and Denise Dillard, PhD What Is the Purpose of This Study? • The purpose of this study was to explore the views of biobanking research among Alaska Native community members and leaders across the state of Alaska using a community-based participatory research approach with tribal and federal partners. • The team undertook a partnership approach to outreach to individual tribes and regional tribal health organizations to partner and guide the study team in the conduct of focus groups in different Alaska Native communities. • In the process of considering biobanking research, Alaska Native people spoke of contextual factors that informed their opinions on research participation and the storage of biological specimens in research. What Are the Problems? What Are the Findings? • Community members described an awareness of past clinical research and surveillance projects, including community-stigmatizing research, which influenced their views on future research participation. • There is a need to actively address and dialogue with community leaders and members regarding the community memory of research when engaging in research with marginalized communities. Who Should Care the Most? • Organizations that want to assess health issues affecting a given community collecting or using biobanked specimens. • Organizations interested in assessing the health status of people within Alaska Native communities. • Organizations and researchers interested in improving the health of Alaska Native people. • Organizations interested in forming community-based participatory research partnerships. Recommendations for Action • Increase the role of Alaska Native community members in research. • Through community and academic partnerships, educate all members of the research team on past clinical research and surveillance projects conducted within the community. [End Page 113] Vanessa Hiratsuka, Jennifer Brown, and Denise Dillard Southcentral Foundation Copyright © 2012 The Johns Hopkins University Press

Community ecology of invasions: direct and indirect effects of multiple invasive species on aquatic communities

With many ecosystems now supporting multiple nonnative species from different trophic levels, it can be challenging to disentangle the net effects of invaders within a community context. Here, we combined wetland surveys with a mesocosm experiment to examine the individual and combined effects of nonnative fish predators and nonnative bullfrogs on aquatic communities. Among 139 wetlands, nonnative fish (bass, sunfish, and mosquitofish) negatively influenced the probability of occupancy of Pacific treefrogs (Pseudacris regilla), but neither invader correlated strongly with occupancy by California newts (Taricha torosa), western toads (Anaxyrus boreas), or California red-legged frogs (Rana draytonii). In mesocosms, mosquitofish dramatically reduced the abundance of zooplankton and palatable amphibian larvae (P. regilla and T. torosa), leading to increases in nutrient concentrations and phytoplankton (through loss of zooplankton), and rapid growth of unpalatable toad larvae (through competitive release). Bullfrog larvae reduced the growth of native anurans but had no effect on survival. Despite strong effects on natives, invaders did not negatively influence one another, and their combined effects were additive. Our results highlight how the net effects of multiple nonnative species depend on the trophic level of each invader, the form and magnitude of invader interactions, and the traits of native community members.

Alien molluscs affect the composition and diversity of native macroinvertebrates in a sandy flat of Lake Neuchâtel, Switzerland

The spread of alien molluscs is a serious threat to native biodiversity in fresh waters. Alien freshwater molluscs may deplete the resources of native species and alter the physical structure of the habitat through their shell mass. These changes might have both positive and negative effects on native community members. We investigated the native macroinvertebrate community in relation to the densities of four alien mollusc species (Corbicula fluminea, Dreissena polymorpha, Potamopyrgus antipodarum and Lithoglyphus naticoides) in a sandy flat of Lake Neuchâtel, Switzerland. The habitat examined was dominated by these alien mollusc species. The abundance of the alien molluscs did not directly impact the native community assembly. However, C. fluminea and D. polymorpha influenced the composition and diversity of native macroinvertebrates by transforming the sandy substratum into a partly hard substratum habitat. Substantial differences in community composition between shallow (<3.5 m) and (≥5 m) deep sites were recorded. At shallow sites, the abundance of D. polymorpha was significantly reduced as a result of depth-selective feeding of ducks. A controlled shell decay study revealed that shells of alien molluscs (C. fluminea, D. polymorpha) persist for a longer period in the sediment than those of native molluscs. Consequently, shells of alien molluscs have a long-lasting impact by modifying the sandy habitat. This form of ecosystem engineering favours the occurrence of several native taxa, but is disadvantageous for other taxa with specific habitat requirements, and thus can be regarded as an indirect impact of competition.

The dynamic consequences of invasion: negative plant-soil feedbacks on natives increase ver the time course of invasion

Abstract Background/Questions/Methods *Exotic species can negatively impact native community members, directly through interference competition, or indirectly by altering interactions between native species and other species such as pathogens and mutualists. Soil microbial communities have been shown to respond to invasive species, yet are relatively stable and may take time to respond to perturbations. For this reason, microbe-mediated effects of invasives on natives may take time to develop and may change throughout the invasion process. Few studies have investigated how species interactions between natives and exotics change during invasions.Acer platanoides was introduced into the US from Europe in 1756 and has since invaded intact forests, lowering understory diversity and inhibiting native tree species regeneration. We hypothesize that A. platanoides invasion will decrease seedling survival in the native A. saccharum by changing the soil microbial community through plant-soil feedbacks (PSF), and this relationship will intensify over the course of an invasion. We collected soil samples from beneath the canopies of both species co-occurring in Michigan forests that had been invaded by A. platanoides for varying time periods. In the greenhouse, we inoculated seedlings of both species with the microbial communities to determine how the soil community affects seedling survival and growth.*b) Results/Conclusion *The microbe-mediated negative effects of A. platanoides on survival of the native congener A. saccharum increased with increasing invasion age (negative correlation between invasion age and A. saccharum survival; r = -0.806, R^2^ = 0.65, p = 0.032). This result was not related to A. platanoides density, suggesting that age of invasion drives this pattern. Contrastingly, invasion age did not significantly influence survival of A. platanoides seedlings, indicating that A. platanoides’ PSF impacts native species but not on conspecific regeneration. Overall, A. platanoides seedlings had increased growth (more and larger leaves) when grown in soil communities collected from the native A. saccharum, but A. saccharum seedlings had reduced growth when grown in conspecific soil (p = 0.044). These results suggest that invasive species may have increased performance in exotic ranges by their ability to modify the soil microbial community in a manner that suppresses the growth of native species.We show the microbial community cultivated by an invader alters the performance of a native plant species, and this effect increases over the course of an invasion. In future work, we plan to identify changes in microbial community composition and the relative abundances of mutualists versus antagonists in response to invasion to identify potential mechanisms.

Engaging Participants in Design of a Native Hawaiian Worksite Wellness Program

Native Hawaiians today face a disproportionately high rate of obesity. The Designing Healthy Worksites (DHW) project investigated existing administrative policies and supports for healthy eating and physical activity at eight Native Hawaiian-serving organizations in Hawai'i, along with employee preferences for worksite wellness programming. We describe the process by which Native Hawaiian researchers and community members worked together to gather formative data to design future worksite wellness programs. A Native Hawaiian doctoral student (JHL) and a Native Hawaiian activist (CKH) spearheaded the project, mentored by a Caucasian professor (KLB) who has worked in Hawaii communities for 30 years. Advisors from the worksites supported the use of environmental assessments (n = 36), administrative interviews (n = 33), focus groups (n = 9), and an employee survey (n = 437) to collect data. We used an interactive process of data collection, sharing, and interpretation to assure mutual agreement on conclusions and future directions. Worksites were at different stages of readiness for worksite wellness programming, suggesting that a toolkit be developed from which agencies could create a program that fit. Activities preferred by large proportions of employees included support groups, experiential nutrition education (e.g., cooking demonstrations and field trips for smart food shopping), food buying clubs, and administrative policies supporting healthy lifestyles. High participation in data collection and interpretation suggest that our methods fostered enthusiasm for worksite wellness programming and for Native Hawaiians as researchers. The team continues to work together to develop and test interventions to promote worksite wellness. Native-directed research that engages administrators and employees in designing programs heightens program acceptability and applicability.

Listening to the Community: Guidance From Native Community Members for Emerging Culturally Responsive Educators

Critical race theory (CRT) emphasizes the importance of listening to the counter-narratives of people from marginalized groups. However, the applicability of CRT in practical settings often remains unclear for educators and scholars. This project offers not only a place for Native community members to share their experiences and ideas, it also provides practical guidance for emerging culturally responsive educators and ways to use themes from narratives to guide future scholarship. As a result of interviews with five Native community members, three themes emerged for non-Native educators working in Native communities: (a) learning from the community, (b) transforming thinking through discomfort, and (c) gaining awareness of positive values. These themes can be used to guide future projects, including reservation-based field experiences and research projects exploring educator thinking in reservation communities.

Native Plant and Microbial Contributions to a Negative Plant-Plant Interaction

A number of hypotheses have been suggested to explain why invasive exotic plants dramatically increase their abundance upon transport to a new range. The novel weapons hypothesis argues that phytotoxins secreted by roots of an exotic plant are more effective against naïve resident competitors in the range being invaded. The common reed Phragmites australis has a diverse population structure including invasive populations that are noxious weeds in North America. P. australis exudes the common phenolic gallic acid, which restricts the growth of native plants. However, the pathway for free gallic acid production in soils colonized by P. australis requires further elucidation. Here, we show that exotic, invasive P. australis contain elevated levels of polymeric gallotannin relative to native, noninvasive P. australis. We hypothesized that polymeric gallotannin can be attacked by tannase, an enzymatic activity produced by native plant and microbial community members, to release gallic acid in the rhizosphere and exacerbate the noxiousness of P. australis. Native plants and microbes were found to produce high levels of tannase while invasive P. australis produced very little tannase. These results suggest that both invasive and native species participate in signaling events that initiate the execution of allelopathy potentially linking native plant and microbial biochemistry to the invasive traits of an exotic species.

Invasive hybrid tiger salamander genotypes impact native amphibians

Although the ecological consequences of species invasions are well studied, the ecological impacts of genetic introgression through hybridization are less understood. This is particularly true of the impacts of hybridization on "third party" community members not genetically involved in hybridization. We also know little about how direct interactions between hybrid and parental individuals influence fitness. Here, we examined the ecological effects of hybridization between the native, threatened California Tiger Salamander (Ambystoma californiense) and the introduced Barred Tiger Salamander (Ambystoma tigrinum mavortium). Native x introduced hybrids are widespread in California, where they are top predators in seasonal ponds. We examined the impacts of early generation hybrids (first 2 generations of parental crosses) and contemporary hybrids derived from ponds where hybrids have been under selection in the wild for 20 generations. We found that most classes of hybrid tiger salamander larvae dramatically reduced survival of 2 native community members, the Pacific Chorus Frog (Pseudacris regilla) and the California Newt (Taricha torosa). We also found that native A. californiense larvae were negatively impacted by the presence of hybrid larvae: Native survival and size at metamorphosis were reduced and time to metamorphosis was extended. We also observed a large influence of Mendelian dominance on size, metamorphic timing and predation rate of hybrid tiger salamanders. These results suggest that both genetic and ecological factors are likely to influence the dynamics of admixture, and that tiger salamander hybridization might constitute a threat to additional pond-breeding species of concern in the region.

Invasion Biologists and the Biofuels Boom: Cassandras or Colleagues

Abstract Modern invasion biology is a new science, with the holy grail of being able to predict the trajectory of particular invasions. Although this goal has yet to be achieved, there has been much progress through experimental research and meticulous study of the scope and mechanisms of existing invasions. Several well-established patterns are relevant to potential biofuel feedstocks: (1) ca. half of all damaging plant invaders were deliberately introduced, not accidental hitchhikers or escapees; (2) some native plants have become invasive; coevolution with native community members was not proof against unexpected damage; (3) many introduced plants were innocuous for decades or even centuries in their new locations before suddenly exploding across the landscape; lack of current observed impact does not guarantee safety; and (4) control or even eradication of widespread invaders is sometimes possible, but it is far from certain and it is often very expensive. We cannot count on effectively managing an in...

ACCESS FOR NATIVE PEOPLE AND THE PUBLIC: EXHIBITS AT THE SMITHSONIAN'S NATIONAL MUSEUM OF THE AMERICAN INDIAN

One of the duties of conservators at the National Museum of the American Indian (NMAI) is to serve as conservation liaison to exhibit projects. The role of the conservation liaison is to ensure that preservation and conservation issues are considered throughout the exhibit development and production, and to ensure that the conservation treatment process incorporates the concerns of other museum staff and Native community members who are involved in the project. This paper uses a recent exhibit Listening to our Ancestors to illustrate how the conservation liaison ensures collaboration both with other NMAI staff and contractors and with Native people who work with the museum to produce exhibits and to involve conservation staff at all stages.

Introduction: Beyond Invisibility and Disaster

August 29, 2005 marked the worst natural disaster in US history. While millions across the world watched their televisions in horror and disbelief, a greater tragedy began to unfold. Centuries of neglect and disinvestment in the indigenous and tribal communities of Louisiana would reach an all-time high in the aftermath of the storm forever known as Katrina. This collection of essays draws on the work of scholars and Native community members from the state of Louisiana and beyond. Although Hurricane Katrina has had an enormous impact on Native American communities in the Gulf Coast area, it also highlights a reality that existed long before the storm struck the region. For mixed-blood communities like the Atakapa/Creole people from Grand Bayou, the storm was a reminder of the social, economic, and political underpinnings that have erased the voices of Native American peoples in the state. According to Atakapa/Creole tribal member Paul Sylvie:

Helping Clients Feel Welcome: Principles of Adapting Treatment Cross-Culturally

ABSTRACT Empirically supported interventions (ESIs) for treating substance problems have seldom been made available to or tested with minority populations. Dissemination of ESIs may help reduce the disproportionate health disparities that exist. However, ESIs may require some adaptation to be effective with minority populations. One ESI, motivational interviewing (MI), appears to be particularly culturally congruent for Native American communities. We worked with Native American community members and treatment providers to adapt MI for Native communities. Reflecting their feedback and suggested amendments, we created and disseminated an intervention manual to improve the accessibility of MI within Native communities. To help guide practitioners working with Native American clients, we used focus-group methodology to explore communication patterns for negotiating change. Native American treatment providers expressed comfort with and enthusiasm for integrating MI into their current practices. Recommendations for adaptations ranged from simple to complex changes. The unique value and challenges of collaboration between academic and community members are presented from each author's perspective. This culturally adapted MI manual will likely improve the accessibility and adoption of MI practices as well as encourage controlled, clinical trials with Native communities.

The Native Telehealth Outreach and Technical Assistance Program: A Community Based Approach to the Development of Multimedia-focused Health Care Information

The development and dissemination of culturally relevant health care information has traditionally taken a "top-down" approach. Governmental funding agencies and research institutions have too often dictated the importance and focus of health-related research and information dissemination. In addition, the digital divide has affected rural communities in such a way that their members often do not possess the knowledge or experience necessary to use technological resources. And, even when they do, their skills may be limited, adequate only for implementing applications and programs designed by others who live and work outside of these communities. This need became the driving force in the creation of the Native Telehealth Outreach and Technical Assistance Program. The goal of the program is to equip Native community members, at both the lay and professional levels, with the means to use technology to address tribal health care needs. The transfer of relevant technical knowledge and skills enables participants to develop projects which enhance the community-wide dissemination of health care information. Nine community health advocates and professionals participated in the initial cohort. Eight of the participants successfully developed multimedia-based projects including Web sites, interactive CD-ROMs, and video focusing on a variety of health concerns. At the conclusion of the 18-month program period, projects were disseminated throughout rural communities. The NTOTAP staff continues to evaluate the use of these projects and their benefits within the rural communities.

EVOLUTIONARY RESPONSES OF NATIVE PLANTS TO NOVEL COMMUNITY MEMBERS

Both ecological and evolutionary processes can influence community assembly and stability, and native community members may respond both ecologically and evolutionarily as additional species enter established communities. Biological invasions provide a unique opportunity to examine these responses of native community members to novel species additions. Here, I use reciprocal transplant experiments among naturally invaded and uninvaded environments, along with experimental removals of exotic species, to determine whether exotic plant competitors and exotic insect herbivores evoke evolutionary changes in native plants. Specifically, I address whether the common native plant species Lotus wrangelianus has responded evolutionarily to a series of biological invasions by adapting to the presence of the exotic plant Medicago polymorpha and the exotic insect herbivore Hypera brunneipennis. Despite differences in selection regimes between invaded and uninvaded environments and the presence of genetic variation for traits relevant to the novel competitive and plant-herbivore interactions, these experiments failed to reveal evidence that Lotus has responded evolutionarily to the double invasion of Medicago followed by H. brunneipennis. However, when herbivory from H. brunneipennis was experimentally reduced, Lotus plants from source populations invaded by Medicago outperformed plants from uninvaded source populations when transplanted into heavily invaded destination environments. Therefore, Lotus showed evidence of adaptation to Medicago invasion but not to the newer invasion of an exotic shared herbivore. The presence of this exotic insect herbivore alters the outcome of evolutionary responses in this system and counteracts adaptation by the native Lotus to invasion by the exotic plant Medicago. This result has broad implications for the conservation of native communities. While native species may be able to adapt to the presence of one or a few exotics, a multitude of invasions may limit the ability of natives to respond evolutionarily to the novel and frequently changing selection pressures that arise with subsequent invasions.

EVOLUTIONARY RESPONSES OF NATIVE PLANTS TO NOVEL COMMUNITY MEMBERS

Both ecological and evolutionary processes can influence community assembly and stability, and native community members may respond both ecologically and evolutionarily as additional species enter established communities. Biological invasions provide a unique opportunity to examine these responses of native community members to novel species additions. Here, I use reciprocal transplant experiments among naturally invaded and uninvaded environments, along with experimental removals of exotic species, to determine whether exotic plant competitors and exotic insect herbivores evoke evolutionary changes in native plants. Specifically, I address whether the common native plant species Lotus wrangelianus has responded evolutionarily to a series of biological invasions by adapting to the presence of the exotic plant Medicago polymorpha and the exotic insect herbivore Hypera brunneipennis. Despite differences in selection regimes between invaded and uninvaded environments and the presence of genetic variation for traits relevant to the novel competitive and plant-herbivore interactions, these experiments failed to reveal evidence that Lotus has responded evolutionarily to the double invasion of Medicago followed by H. brunneipennis. However, when herbivory from H. brunneipennis was experimentally reduced, Lotus plants from source populations invaded by Medicago outperformed plants from uninvaded source populations when transplanted into heavily invaded destination environments. Therefore, Lotus showed evidence of adaptation to Medicago invasion but not to the newer invasion of an exotic shared herbivore. The presence of this exotic insect herbivore alters the outcome of evolutionary responses in this system and counteracts adaptation by the native Lotus to invasion by the exotic plant Medicago. This result has broad implications for the conservation of native communities. While native species may be able to adapt to the presence of one or a few exotics, a multitude of invasions may limit the ability of natives to respond evolutionarily to the novel and frequently changing selection pressures that arise with subsequent invasions.

A Polluting Concept of Culture: Native Artefacts Contaminated with Toxic Preservatives

This research examines the practical and theoretical fallout of the toxic methods used by museum conservators to preserve native artefacts and regalia. These conservation practices, dating to the late 19th and early 20th centuries, were undertaken before the age of museum professionalisation and within a larger context of cultural assimilation. Many of these chemical preservatives produce the same harmful effects in humans as they do in the organisms they were designed to eradicate. As these contaminated artefacts are repatriated, members of native communities who attempt to reintegrate them into ceremonial and daily practice are put at significant health risk. Not only do these pollutants undermine the stated goals of repatriation but they also stand as a literal instance of the way in which a hegemonic and interpreting culture has metaphorically contaminated the culture it has purported to preserve and display.

Cancer Control Research Training for Native Researchers: A Model for Development of Additional Native Researcher Training Programs

Although Native populations suffer a disproportionate cancer burden, studies of risk reduction for cancer incidence among Native peoples have not been strongly supported by federal or private funding sources, and few published data are available to assess the success of cancer control efforts among Native community members. Furthermore, cancer etiologic investigations and cancer control studies in Native populations have not commonly included Native researchers in principal roles. This lack of involvement is related primarily to the low numbers of Native researchers who have adequate training and experience to address Native cancer problems. Although numerous social and biological scientists who have Native status are engaged in productive research careers, the encouragement that has been offered Native students to formulate career goals devoted to cancer etiology or cancer control in Native peoples has had limited success. To address cancer-related challenges adequately and to implement successful cancer control programs in Native communities, more well-trained, culturally competent researchers are required. The Native Researchers’ Cancer Control Training Program (NRCCTP) was designed to address this

Unlikely Alliances: Treaty Conflicts and Environmental Cooperation between Native American and Rural White Communities

Native Americans and their white rural neighbors have long been archetypal enemies in conflicts over natural resources. In particular regions of the country in the late twentieth century, tribes fighting for their treaty rights dealt with local white farmers, ranchers, commercial fishers, or sportfishers as the main obstacle to securing treaty-guaranteed access to fish, game, or water. As the tribes secured these rights, many rural whites joined an anti-Indian movement to oppose tribal sovereignty. Yet in some of these same resource conflict zones, beginning in the 1970s, members of Native and rural white communities unexpectedly came together to protect the same natural resources from a perceived outside threat. Environmental alliances began to bring together Native Americans and rural white resource users in areas of the country where no one would have predicted or even imagined them. In an evolution that has continued into the 2000s, some Native and rural white communities formed grassroots alliances that have become a key element in the protection of natural resources. By comparing case studies of these “unlikely alliances” in the states of Washington, Oregon, Nevada, Montana, South Dakota, and Wisconsin, I hoped to find reasons why these communities turned from conflict to cooperation.1 The evolution went through four general and often overlapping stages. First, Native Americans asserted their cultural autonomy and tribal sovereignty. Second, a backlash from some rural whites created a conflict around