235 research outputs found
Integrating Traditional and Scientific Knowledge through Collaborative Natural Science Field Research: Identifying Elements for Success
We discuss two recent projects to examine the role of collaborative environmental fieldwork both in research and in the interactions between academically trained researchers and experienced local residents. The Bidarki Project studied black leather chitons (Katharina tunicata) in the lower Kenai Peninsula, Alaska. Its conclusion that chiton declines are part of a serial decline of intertidal invertebrates drew on collaborative fieldwork, archaeological data, historical records, and interviews with local residents. The Siku-Inuit-Hila Project studied sea ice in Barrow, Alaska; Clyde River, Nunavut; and Qaanaaq, Greenland. Quantitative data from locally maintained observation sites were supplemented by knowledge exchanges among hunters from the communities and by discussion in local working groups to develop an understanding of the physical dynamics and human uses of sea ice at each locale. We conclude that careful planning and preparation, along with the effort to build strong personal relationships, can increase the likelihood that collaborative fieldwork will be productive, enjoyable, and rewarding.Nous discutons de deux rĂ©cents projets ayant eu pour but dâexaminer le rĂŽle dâĂ©tudes environnementales collaboratives sur le terrain, tant sur le plan de la recherche que sur le plan des interactions entre les chercheurs universitaires et les rĂ©sidents expĂ©rimentĂ©s des localitĂ©s visĂ©es. Le projet Bidarki se penchait sur les chitons noirs (Katharina tunicata) de la basse pĂ©ninsule Kenai, en Alaska. La conclusion selon laquelle le dĂ©clin des chitons fait partie dâun dĂ©clin en sĂ©rie dâinvertĂ©brĂ©s intertidaux sâappuie sur des Ă©tudes collaboratives sur le terrain, sur des donnĂ©es archĂ©ologiques, sur des dossiers historiques ainsi que sur des entrevues de rĂ©sidents des localitĂ©s. Pour sa part, le projet Siku-Inuit-Hila a eu comme objectif dâĂ©tudier la glace de mer Ă Barrow, en Alaska; Ă Clyde River, au Nunavut; et Ă Qaanaaq, au Groenland. Les donnĂ©es quantitatives provenant de lieux dâobservation entretenus localement ont Ă©tĂ© supplĂ©mentĂ©es par les Ă©changes de connaissances des chasseurs des collectivitĂ©s et par les discussions de groupes de travail locaux visant Ă mieux comprendre la dynamique physique et lâutilisation humaine de la glace de mer Ă chaque endroit. Nous en concluons que des travaux de planification et de prĂ©paration attentionnĂ©s, accompagnĂ©s dâefforts visant Ă nouer des liens personnels Ă©troits, peuvent accroĂźtre la possibilitĂ© que les Ă©tudes collaboratives sur le terrain soient productives, agrĂ©ables et valorisantes
Expanded Consumer Niche Widths May Signal an Early Response to Spatial Protection
Marine management interventions are increasingly being implemented with the explicit goal of rebuilding ocean ecosystems, but early responses may begin with alterations in ecological interactions preceding detectable changes in population-level characteristics. To establish a baseline from which to monitor the effects of spatial protection on reef fish trophic ecology and track future ecosystem-level changes, we quantified temperate reef fish densities, size, biomass, diets and isotopic signatures at nine sites nested within two fished and one five-year old marine protected area (MPA) on the northwest coast of Canada. We calculated rockfish (Sebastes spp.) community and species-specific niche breadth for fished and protected areas based on ÎŽ13C and ÎŽ15N values. We found that rockfish community niche width was greater inside the MPA relative to adjacent fished reefs due to an expanded nitrogen range, possibly reflecting early changes in trophic interactions following five years of spatial protection. Our data also demonstrated that the MPA had a positive effect on the ÎŽ15N signature of rockfish (i.e., trophic position), but the effect of rockfish length on its own was not well-supported. In addition, we found a positive interaction between rockfish length and ÎŽ15N signature, such that ÎŽ15N signatures of rockfish caught within the MPA increased more rapidly with body size than those caught in fished areas. Differences in rockfish size structure and biomass among fished and unfished areas were not clearly evident. Species of rockfish and lingcod varied in trophic and size responses, indicating that life-history traits play an important role in predicting MPA effects. These results may suggest early changes in trophic behavior of slow-growing rockfish due to predation risk by faster growing higher trophic level predators such as lingcod inside MPAs established on temperate reefs. Consequently, spatial protection may restore both the trophic and behavioral roles of previously fished consumers earlier and in measurable ways sooner than observable changes in abundance and size
The changing landscape of conservation science funding in the United States
To understand the changing role of funding sources in shaping conservation science in the United States, we analyzed acknowledgments from published studies, trends in research funding, and survey responses from conservation scientists. Although the U.S. federal government was the most frequently acknowledged source of support overall, U.S. foundations and NGOs were the predominant sources for tropical and socioeconomic research. Acknowledgments of foundation support for conservation research increased over the last two decades, while recognition of federal funds declined. Concordant trends in funding and acknowledgments indicated a changing landscape for conservation science, in which federal support has not kept pace with the growth in conservation research efforts or needs. Survey responses from conservation scientists about their funding sources were consistent with acknowledgment data, and most (64%) indicated that shifts in funding sources and amounts affected the type of research they conduct. Ongoing changes in the funding landscape shape the direction of conservation research and may make conservation science more vulnerable to economic recessions
Pacific Herring Spawns Provide Temporal Subsidies to Nearshore Ecosystems
Pacific herring (Clupea pallasi), low trophic level fish at the base of many pelagic food webs, are integral to coastal social-ecological systems in North America. This migratory species provides a temporal subsidy to coastal systems by moving from offshore to nearshore waters for annual spawning events. Spawning migrations support subsistence and commercial fisheries, and provide an ecological pulse in prey availability. In coastal British Columbia, we quantified changes in rockfish (Sebastes maliger and caurinus) diet composition surrounding spawn events to understand the temporal importance of this subsidy. We found that the percentage of fish in rockfish diets switched from 30% fish tissue pre spawn to 34% herring roe post spawn, and that this shift peaked at 2-3 weeks post spawn events. This dietary change is most pronounced in females, where herring roe accounted for an average of 29% of stomach contents through the month following a spawn event. This may be due to differences in energy requirements for gravid females. Stable isotope concentrations of fish tissues (muscle, heart, liver, gonads) also showed evidence of herring nutrient assimilation. Determining these ecosystem-level associations is key to understanding both the social and ecological consequences of herring spawn declines
Hydrodynamic regime determines the magnitude of surface sediment \u27blue carbon\u27 stocks in British Columbia eelgrass meadows
Carbon storage in marine vegetated habitats (blue carbon) is increasingly being considered in carbon financing and coastal ecosystem management. Amongst other ecosystem functions, seagrass meadows are reported to be highly efficient at sequestering and storing significant amounts of carbon. However, seagrass blue carbon data remain sparse and regionally biased to tropical regions. In the Pacific Northwest, we lack information on the magnitude and variability of carbon stocks, as well as local drivers of variability. We collected sediment cores from six eelgrass meadows on the central coast of British Columbia, Canada, to quantify sedimentary organic carbon (Corg) stocks and accumulation rates. Carbon stocks exhibited 10-fold variability (335.35 â 3664. 48 g Corg m-2) in the top 20cm of sediment; these values align with other temperate eelgrass meadows, but are lower than reported global seagrass values. On average, Corg stocks within seagrass beds and adjacent unvegetated habitat overlapped, although stocks in the meadow interior (1392.05 g Corg m-2) were greater than those along meadow edges (1129.82 g Corg m-2) and in adjacent unvegetated sediments (977.10 g Corg m-2). Corg accumulation rates ranged from 12.57 to 50.45 g Corg m-2 year-1, lower than the global average reported for seagrasses (138 g Corg m-2 year-1), but again similar to other eelgrass meadows. Further, Corg in sediments beneath eelgrass meadows appears to be largely from non-eelgrass sources (terrestrial, benthic microalgae and macroalgae). Generalized linear mixed effects models suggest that hydrodynamic regime is the strongest driver of carbon stocks in the top 5cm of sediment, more important than the structural complexity of seagrass beds, or the proportion of fine sediments. Lower water velocities may allow greater deposition of particles within meadows, together with reduced erosion and resuspension. These results support physical characteristics over seagrass features as primary determinants of blue carbon storage in nearshore soft sediment habitats
Measuring Social-Ecological Resilience Reveals Opportunities for Transforming Environmental Governance
Understanding the resilience of social-ecological systems can advance our ability to transform environmental governance and achieve ecologically sustainable and socially just outcomes. However, measuring this multidimensional emergent system property has been elusive. We translated theoretical principles of resilience into ecological and social metrics and used expert knowledge to assess how they have changed through three sequential governance regimes of the Pacific herring fishery in northwestern Canada. We showed a significant reduction in system-wide resilience between previous Indigenous and historical colonial governance regimes, and limited change with the onset of the latest environmental justice era. We also detected recent signs of recovery among several metrics of resilience, thereby signaling that this system exhibits the preconditions for governance transformation. Pinpointing the erosion and recovery of attributes that confer social-ecological resilience can reveal leverage points and highlight strategic pathways to enable deliberate transformation toward a more ecologically sustainable and socially just future
Indigenous Knowledge of Key Ecological Processes Confers Resilience to a Small-scale Kelp Fishery
1. Feedbacks between social and ecological processes can lead to sustainable stewardship practices that support ecological resilience among harvested populations. This is evident along the world\u27s coast lines, where Indigenous knowledge systems have facilitated millennia of humanânature coexistence. However, socialâecological conditions globally are quickly shifting, posing challenges for coastal Indigenous communities where customary harvest of ocean resources, such as kelps, needs to adapt to growing markets, novel climates and changing governance regimes. Consequently, a pressing need exists to determine how specific ecological and social variables drive key dynamics within coupled humanâocean systems.
2. Motivated by the information needs of an Indigenous community on Canada\u27s Pacific Coast, we co-designed a traditional harvest experiment, field surveys and semi-directed interviews with Indigenous resource users and managers to measure the ecological resilience of the feather boa kelp Egregia menziesii to harvest and determine what environmental variables most affected its recovery. We wove these results with information on current stewardship practices to inform future management of this slow-growing perennial kelp based on Indigenous knowledge and western science.
3. We found that Egregia recovered from traditional harvest levels faster than expected with minimal impact on its productivity because plants sprouted new fronds. In fact, traditional harvest levels of Egregia mimicked natural frond loss. Indigenous knowledge and empirical ecological evidence revealed the importance of individual plant size, site-specific seawater temperature and wave exposure in driving Egregia recovery. Indigenous stewardship practices reflected these ecological relationships in the practice of selecting large plants from sites with healthy patches of Egregia. While we documented key social controls of harvest, current self-reported harvest levels of kelp fronds were two times greater than the stated social norm, but only 1.2 times greater in terms of kelp biomass.
4. Consequently, traditional harvest protocols facilitate Egregia recovery and promote its sustained use. However, its ecological resilience is susceptible to the erosion of customary practices and warming ocean temperatures.
5. Co-produced research that mobilizes multiple bodies of knowledge can enhance our understanding of socialâecological resilience, empower local decision makers and democratize the science and practice of natural resource management
Enabling Coexistence: Navigating Predatorâinduced Regime Shifts in Humanâocean Systems
1. Rapid systemâwide changes triggered by predators can pose considerable challenges to people. In the Northeast Pacific, the recovery of sea otters Enhydra lutris following their extirpation due to the 18th and 19th century fur trade is driving a socialâecological regime shift with profound implications. While the ecological consequences of this shift are well documented, very little research has examined the conditions that enable or constrain people\u27s ability to adapt to the social, economic and cultural changes that transpire.
2. Through a collaborative partnership and workshops with Indigenous knowledge holders spanning Alaska to British Columbia, along with quantitative and qualitative interviews in two Indigenous communities among the first to experience sea otter recovery, we examined people\u27s perceptions of the socialâecological conditions that affect their ability to adapt to these changes.
3. We found that communities differed in their relative rankings of adaptationâenabling conditions; however, the following four broad strategies were perceived as critical to improving coexistence with sea otters: (a) strengthening Indigenous governance and decisionâmaking authority; (b) promoting adaptive coâmanagement; (c) weaving Indigenous knowledge and Western science into management plans and (d) establishing learning platforms. Both communities also identified that increased livelihood options and financial assistance would not compensate for lost food security.
4. Differences in enabling conditions and attitudes towards sea otters within and between communities can be attributed to the socialâecological and political context in which sea otter recovery occurs.
5. Our study suggests that enhancing Indigenous peoples\u27 ability to adapt to predatorâinduced regime shifts will require a transformation in current resource governance systems if we are to navigate towards an ecologically sustainable and socially just operating space. Overall, this work highlights the need for more Indigenous authority, knowledge and leadership in addressing predatorâinduced regime shifts in coupled humanâocean systems.
 
Pentraxin-3 is a PI3K signaling target that promotes stem cellâlike traits in basal-like breast cancers
Basal-like breast cancers (BLBCs) exhibit hyperactivation of the phosphoinositide 3-kinase (PI3K) signaling pathway because of the frequent mutational activation of the PIK3CA catalytic subunit and the genetic loss of its negative regulators PTEN (phosphatase and tensin homolog) and INPP4B (inositol polyphosphate-4-phosphatase type II). However, PI3K inhibitors have had limited clinical efficacy in BLBC management because of compensatory amplification of PI3K downstream signaling loops. Therefore, identification of critical PI3K mediators is paramount to the development of effective BLBC therapeutics. Using transcriptomic analysis of activated PIK3CA-expressing BLBC cells, we identified the gene encoding the humoral pattern recognition molecule pentraxin-3 (PTX3) as a critical target of oncogenic PI3K signaling. We found that PTX3 abundance is stimulated, in part, through AKT- and nuclear factor ÎșB (NF-ÎșB)-dependent pathways and that presence of PTX3 is necessary for PI3K-induced stem cell-like traits. We further showed that PTX3 expression is greater in tumor samples from patients with BLBC and that it is prognostic of poor patient survival. Our results thus reveal PTX3 as a newly identified PI3K-regulated biomarker and a potential therapeutic target in BLBC
MSC-Regulated MicroRNAs Converge on the Transcription Factor FOXP2 and Promote Breast Cancer Metastasis
SummaryMesenchymal stem/stromal cells (MSCs) are progenitor cells shown to participate in breast tumor stroma formation and to promote metastasis. Despite expanding knowledge of their contributions to breast malignancy, the underlying molecular responses of breast cancer cells (BCCs) to MSC influences remain incompletely understood. Here, we show that MSCs cause aberrant expression of microRNAs, which, led by microRNA-199a, provide BCCs with enhanced cancer stem cell (CSC) properties. We demonstrate that such MSC-deregulated microRNAs constitute a network that converges on and represses the expression of FOXP2, a forkhead transcription factor tightly associated with speech and language development. FOXP2 knockdown in BCCs was sufficient in promoting CSC propagation, tumor initiation, and metastasis. Importantly, elevated microRNA-199a and depressed FOXP2 expression levels are prominent features of malignant clinical breast cancer and are associated significantly with poor survival. Our results identify molecular determinants of cancer progression of potential utility in the prognosis and therapy of breast cancer
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