Plant distribution and climate data across western North America

Using an extensive network of occurrence records for 293 plant species collected over the past 40 years across a climatically diverse geographic section of western North America, we find that plant species distributions were just as likely to shift upwards (i.e., towards higher elevations) as downward (i.e., towards lower elevations) - despite consistent warming across the study area. Although there was no clear directional response to climate warming across the entire study area, there was significant region-to region- variation in responses (i.e. from as many as 73% to as few as32% of species shifting upward or downward). To understand the factors that might be controlling region-specific distributional shifts, we explored the relationship between the direction of change in distribution limits and the nature of recent climate change. We found that the direction of distribution limit shifts was explained by an interaction between the rate of change in local summer temperatures and seasonal precipitation. Specifically, species shifted upward at their upper elevational limit when snowfall declined at slower rates and minimum temperatures increased. By contrast, species shifted upwards at their lower elevation limit when maximum temperatures increased or both temperature and precipitation decreased. Our results suggest that future species' elevational distribution shifts will be complex, depending on the interaction between seasonal temperature and precipitation change.

The status of the beavers of western North America with a consideration of the factors in their speciation ...

Pub. also as University of California publications in zoology, v. 12, no. 15, March 20, 1916.

Workshop on climate variability of the Eastern North Pacific and Western North America : 4 to 8 March 1984, Asilomar Conference Center, Pacific Grove (Monterey Peninsula), California : [abstracts]

Mode of access: Internet.

The mountain ants of western North America.

"Proceedings of the American Academy of Arts and Sciences. Vol.52. no.8 January, 1917."

Proceedings of the Symposium on Research and Management of Annosus Rood Disease (Heterobasidion annosum) in Western North America, April 18-21, 1989, Monterey, California /

Includes bibliographical references.

Distribution of the monarch butterfly, Danaus plexippus (L.) (Lepidoptera : Nymphalidae), in western North America

The standard model for the migration of the monarch butterfly in western North America has hitherto been movement in the autumn to overwintering sites in coastal California, followed by a return inland by most individuals in the spring. This model is based largely on observational and limited tagging and recovery data. In this paper we test the model by plotting many years of museum and collection records on a monthly basis on a map of the region. Our plots suggest a movement of Oregon, Washington and other north-western populations of summer butterflies to California in the autumn, but movement of more north-easterly populations (e.g. from Idaho and Montana) along two pathways through Nevada, Utah and Arizona to Mexico. The more westerly of these two pathways may follow the Colorado River south as indicated by museum records and seasonal temperature data. The eastern pathway may enter northern Utah along the western scarp of the Wasatch Mountains and run south through Utah and Arizona. Further analysis of distributions suggests that monarch butterflies in the American West occur primarily along rivers, and there are observations indicating that autumn migrants often follow riparian corridors. More data are needed to test our new model; we suggest the nature of the data required. (c) 2005 The Linnean Society of London.

Genetic evidence supports recolonisation by Mya arenaria of western Europe from North America

The softshell clam Mya arenaria (L.) is currently widespread on the east and west coasts of North America. This bivalve also occurs on western European shores, where the post-Pleistocene origin of the species, whether introduced or relict, has been debated. We collected 320 M. arenaria from 8 locations in Europe and North America. Clams (n = 84) from 7 of the locations were examined for mitochondrial DNA variation by sequencing a section of the cytochrome oxidase 1 (COX1) gene. These were analysed together with 212 sequences, sourced from GenBank, from the same gene from 12 additional locations, chiefly from eastern North America but also 1 site each from western North America and from western Europe. Ten microsatellite loci were also investigated in all 320 clams. Nuclear markers showed reduced levels of variation in certain European samples. The same common COX1 haplotypes and microsatellite alleles were present throughout the range of M. arenaria, although significant differences were identified in haplotypic and allelic composition between many samples, particularly those from the 2 continents (Europe and North America). These findings support the hypothesis of post-Pleistocene colonisation of European shores from eastern North America (and the recorded human transfer of clams from the east to the west coast of North America in the 19th century).

Morphological differentiation of Betula (birch) pollen in northwest North America and its palaeoecological application

Lake sediments from arcto-boreal regions commonly contain abundant Betula pollen. However, palaeoenvironmental interpretations of Betula pollen are often ambiguous because of the lack of reliable morphological features to distinguish among ecologically distinct Betula species in western North America. We measured the grain diameters and pore depths of pollen from three tree-birch species (B. papyrifera, B. kenaica and B. neoalaskana) and two shrub-birch species (B. glandulosa and B. nana), and calculated the ratio of grain diameter to pore depth (D/P ratio). No statistical difference exists in all three parameters between the shrub-birch species or between two of the tree-birch species (B. kenaica and B. papyrifera), and B. neoalaskana is intermediate between the shrub-birch and the other two tree-birch species. However, mean pore depth is significantly larger for the tree species than for the shrub species. In contrast, mean grain diameter cannot distinguish tree and shrub species. Mean D/P ratio separates tree and shrub species less clearly than pore depth, but this ratio can be used for verification. The threshold for distinguishing pollen of tree versus shrub birch lies at 2.55 μm and 8.30 for pore depth and D/P ratio, respectively. We'applied these thresholds to the analysis of Betula pollen in an Alaskan lake-sediment core spanning the past 800 years. Results show that shrub birch increased markedly at the expense of tree birch during the‘Little Ice Age’; this patten is not discernible in the profile of total birch pollen.

Simulations of forest loss in North America, the Amazon, and combined using the Community Earth System Model

The netcdf files in this archive comprise climate model output from Community Earth System Model for experiments looking at forest loss over Western North America and the Amazon. For further description of the model and configuration for these experiments please see the accompanying manuscript: Synergistic ecoclimate teleconnections from forest loss in different regions structure global ecological responses Elizabeth S. Garcia, Abigail L. S. Swann, Juan C. Villegas, David D. Breshears, Darin J. Law, Scott R. Saleska, and Scott C. Stark published in PLOS ONE, 2016. Contact information in README.txt

Contrasting spatio-temporal climatic niche dynamics during the eastern and western invasions of spotted knapweed in North America

Aim The spotted knapweed (Centaurea stoebe), a plant native to south-east and central Europe, is highly invasive in North America. We investigated the spatio-temporal climatic niche dynamics of the spotted knapweed in North America along two putative eastern and western invasion routes. We then considered the patterns observed in the light of historical, ecological and evolutionary factors. Location Europe and North America. Methods The niche characteristics of the east and west invasive populations of spotted knapweed in North America were determined from documented occurrences over 120 consecutive years (1890-2010). The 2.5 and 97.5 percentiles of values along temperature and precipitation gradients, as given by the two first axes of a principal component axis (PCA), were then calculated. We additionally measured the climatic dissimilarity between invaded and native niches using a multivariate environmental similarity surface (MESS) analysis. Results Along both invasion routes, the species established in regions with climatic conditions that were similar to those in the native range in Europe. An initial spread in ruderal habitats always preceded spread in (semi-)natural habitats. In the east, the niche gradually increased over time until it reached limits similar to the native niche. Conversely, in the west the niche abruptly expanded after an extended time lag into climates not occupied in the native range; only the native cold niche limit was conserved. Main conclusions Our study reveals that different niche dynamics have taken place during the eastern and western invasions. This pattern indicates different combinations of historical, ecological and evolutionary factors in the two ranges. We hypothesize that the lack of a well-developed transportation network in the west at the time of the introduction of spotted knapweed confined the species to a geographically and climatically isolated region. The invasion of dry rangelands may have been favoured during the agricultural transition in the 1930s by release from natural enemies, local adaptation and less competitive vegetation, but further experimental and molecular studies are needed to explain these contrasting niche patterns fully. Our study illustrates the need and benefit of applying large-scale, temporally explicit approaches to understanding biological invasions.

Molluscan carbonate geochemistry and paleoceanography of the Late Cretaceous western interior seaway of North America

North Amerlc8 W8S inundated by fJ major eplcontlnental sea during ihe C:retaceo.us Period. The sOljihw6rd transgression of th.e northern Boreal See along the ~\festern Interior Seaway resulted in a meetlng with the northward edv6nclng waters from the GUlf of Mexico (Obradovich and Cobban, 1975). Th1s link was 1n eXlstence by late Albien time and 6llowed for the comm1ngl1ng of the prol1ferous Arctic and Gulf rnar1ne faunas (F1g. 1). By early Campanlan time, there was a widening of B6ffln Bay wlth a slrnult8neous subsidence 1n the Arct1c Archlpelago and Sverdrup 6as1n (W11liam and Stelck, 1975). Williams and Burk (1964) found 6 break 1n the marines sedlmentatlon in the f1anltoba area, suggesting Bland corlnectlon from the Dlstrlct of Keewatln through eastern M6fl1toba to the lake Sl~perlor reglon, lmplying that the only dlrect connection between the Interlor Sea with Baffln Bay, was yia the Arct1c. This hiatus was also documented by Meek and Hayden (1861) ln the United states between the Niobrara and Pierre Format1ons. Jeletzky (1971) suggested that the retreat of the sea towards the east was by a serles of strong pulses resultlng in the regression of the Campanlan and M66str1chtlan seas. During ttle Cretaceous1 the r1s1ng Corl1111era caused the western shoreline of the Interlor Sea to migrate eastwards and the Cordillera'l detritus produced deltaic cornplexes from the Mackenzie Valley to Ne\N Mexlcoo The foreland basin was continually subslding and thls down\",arplng aided in the eastward m1gration of the western shorel1ne. Thls also lndicates that trle water 'tIes becom1ng deeper in the central Plains sect10n of the Seaway (Fig. 2).

Policy Change in Comparative Contexts: Applying the Advocacy Coalition Framework Outside of Western Europe and North America

The advocacy coalition framework (ACF) is one of the most frequently applied theories of the policy process. Most applications have been in Western Europe and North America. This article provides an overview of the ACF, summarizes existing applications outside of Western Europe and North America, and introduces the special issue that features applications of the ACF in the Philippines, China, India, and Kenya. This article concludes with an argument for the continued application of the ACF outside of Western Europe and North America and a research agenda for overcoming challenges in using the ACF in comparative public policy research.