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SPECIAL REPORT:CLIMATE OF OPPORTUNITY
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Awareness about climate change is at an all-time high. Will this surge of attention translate into more jobs for climate scientists?
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Climate Science Documents
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Species invasions and extinction: The future of native biodiversity on islands
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Predation by exotic species has caused the extinction of many native animal species on islands, whereas competition from exotic plants has caused few native plant extinctions. Exotic plant addition to islands is highly nonrandom, with an almost perfect 1 to 1 match between the number of naturalized and native plant species on oceanic islands. Here, we evaluate several alternative implica- tions of these findings. Does the consistency of increase in plant richness across islands imply that a saturation point in species richness has been reached? If not, should we expect total plant richness to continue to increase as new species are added? Finally, is the rarity of native plant extinctions to date a misleading measure of the impact of past invasions, one that hides an extinction debt that will be paid in the future? By analyzing historical records, we show that the number of naturalized plant species has increased linearly over time on many individual islands. Further, the mean ratio of naturalized to native plant species across islands has changed steadily for nearly two centuries. These patterns suggest that many more species will become naturalized on islands in the future. We also discuss how dynamics of invasion bear upon alternative saturation scenarios and the implications these scenarios have for the future retention or extinction of native plant species. Finally, we identify invasion-motivated research gaps (propagule pressure, time-lags to extinction, abundance shifts, and loss of area) that can aid in forecasting extinction and in developing a more comprehensive theory of species extinctions.
birds plants species saturation
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Climate Science Documents
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Spencer, Sandy
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Expertise Search
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Spooner Vaughn 2006.pdf
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Resources
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TRB Library
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SPA-STE
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Spot fin Chub Spawning in Tellico River
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For a little more than 10 years, Conservation Fisheries has been working to re-establish spotfin chub into the Tellico River in eastern Tennessee. These spectacular, turquoise minnows (only the males develop this color and only during summertime spawning), are highly specialized and closely associated with clean, current swept, bedrock habitats. During spawning season, the males become very territorial and stake out crevices in the rocks where the females will ultimately deposit the eggs. While males vigorously defend these territories, they do not provide any direct care to the eggs and larvae. The spotfin chub is federally threatened.
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Training
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Videos and Webinars
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SpotlightonNationalParks
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Spotlight on National Parks
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National Park Service Spotlights
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SprawlStreams.pdf
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Climate Science Documents
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St John 1974.pdf
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Resources
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TRB Library
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SPA-STE
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Stability and Diversity of Ecosystems
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Understanding the relationship between diversity and stability requires a knowledge of how species interact with each other and how each is affected by the environment. The relationship is also complex, because the concept of stability is multifaceted; different types of stability describing different properties of ecosystems lead to multiple diversity-stability relationships. A growing number of empirical studies demonstrate positive diversity-stability relationships. These studies, however, have emphasized only a few types of stability, and they rarely uncover the mechanisms responsible for stability. Because anthropogenic changes often affect stability and diversity simultaneously, diversity-stability relationships cannot be understood outside the context of the environmental drivers affecting both. This shifts attention away from diversity-stability relationships toward the multiple factors, including diversity, that dictate the stability of ecosystems.
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Climate Science Documents
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Stakeholder Webinar: Understanding the Human Dimensions of Private Lands Conservation and Management
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Series of speakers on human dimensions of working with private landowners to effect conservation.
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