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Thorne J.H.,University of California at Davis | Santos M.J.,The History Project | Bjorkman J.H.,University of California at Davis
PLoS ONE | Year: 2013

Assessment of landscape change is critical for attainment of regional sustainability goals. Urban growth assessments are needed because over half the global population now lives in cities, which impact biodiversity, ecosystem structure and ecological processes. Open space protection is needed to preserve these attributes, and provide the resources humans need. The San Francisco Bay Area, California, is challenged to accommodate a population increase of 3.07 million while maintaining the region's ecosystems and biodiversity. Our analysis of 9275 km2 in the Bay Area links historic trends for three measures: urban growth, protected open space, and landcover types over the last 70 years to future 2050 projections of urban growth and open space. Protected open space totaled 348 km2 (3.7% of the area) in 1940, and expanded to 2221 km2 (20.2%) currently. An additional 1038 km2 of protected open space is targeted (35.1%). Urban area historically increased from 396.5 km2 to 2239 km2 (24.1% of the area). Urban growth during this time mostly occurred at the expense of agricultural landscapes (62.9%) rather than natural vegetation. Smart Growth development has been advanced as a preferred alternative in many planning circles, but we found that it conserved only marginally more open space than Business-as-usual when using an urban growth model to portray policies for future urban growth. Scenarios to 2050 suggest urban development on non-urban lands of 1091, 956, or 179 km2, under Business-as-usual, Smart Growth and Infill policy growth scenarios, respectively. The Smart Growth policy converts 88% of natural lands and agriculture used by Business-as-usual, while Infill used only 40% of those lands. Given the historic rate of urban growth, 0.25%/year, and limited space available, the Infill scenario is recommended. While the data may differ, the use of an historic and future framework to track these three variables can be easily applied to other metropolitan areas. © 2013 Thorne et al.

Nouvellet P.,University of Oxford | Nouvellet P.,University Paris - Sud | Rasmussen G.S.A.,University of Oxford | Rasmussen G.S.A.,The History Project | And 2 more authors.
Journal of Zoology | Year: 2012

From insects to mammals, many animals engage in behaviours known to follow cyclic patterns over days (e.g. singing, diving or foraging behaviours). Many of them are regulated by external factors, such as light intensity, and are thus associated with sunrise, sunset or zenith. However, these astronomical events do not occur at the same time everyday: they vary with both the time of the year and the latitude. Logically, therefore, behaviour timing should be recorded relative to these events. Yet, in the field, recording the timing of behaviour is much less difficult with a clock, which is often deemed a suitable common proxy. In this paper, we assess the potential methodological problems associated with analyzing behaviours on the basis of clock time rather than with the actual position of the sun. To demonstrate the important difference between these methods of analysis, we first simulated a behaviour set at sunrise and compared the time of occurrence with the two methods. We then used a dataset, based on a long-term monitoring of hunting behaviour of African wild dogs, Lycaon pictus, to reveal how using clock time can result in erroneous assumptions about behaviour. Finally, we investigated the occurrence of sun time records in published field studies. As a majority of them did not take into account the relevance of astronomical events, it is probable that many result in faulty behavioural timings. The model presented can change clock-recorded time into actual deviation from astronomical events to assist current protocols as well as correct the already recorded datasets. © 2011 The Authors. Journal of Zoology © 2011 The Zoological Society of London.

Smith T.D.,The History Project | Reeves R.R.,Okapi Wildlife Associates
Marine Fisheries Review | Year: 2010

Whaling for humpback whales, Megaptera novaeangliae, in the North Atlantic Ocean has occurred in various forms (e.g. for local subsistence, for oil to be sold commercially, using hand harpoons and deck-mounted cannons, using oar-driven open boats and modern powered catcher boats) from the early 1600's to the present. Several previous attempts to estimate the total numbers of humpback whales removed were considered close to comprehensive, but some uncertainties remained. Moreover, the statistical uncertainty was not consistently presented with the previous estimates. Therefore, we have pursued several avenues of additional data collection and conducted further analyses to close outstanding data gaps and address remaining issues. Our new estimates of landings and total removals of humpback whales from the North Atlantic are 21,476 (SE=214) and 30,842 (SE=655), respectively. These results include statistical uncertainty, reflect new data and improved analysis methods, and take account of some fisheries for which estimates had not been made previously. The new estimates are not sufficiently different from previous ones to resolve the major inconsistencies and discrepancies encountered in efforts to determine the conservation status of humpback whale populations in the North Atlantic.

Shore whaling along North America's California and Baja California coasts during 1854-99 was ancillary to the offshore and alongshore American whale fishery, which had begun in the North Pacific in the early 1800's and was flourishing by the 1840's. From its inception at Monterey, Calif, in the mid 1850's, the shore fishery, involving open boats deployed from land to catch and tow whales for processing, eventually spread from Monterey south to San Diego and Baja California and north to Crescent City near the California-Oregon border. It had declined to a relict industry by the 1880's, although sporadic efforts continued into the early 20th century. The main target species were gray whales, Eschrichtius robustus, and humpback whales, Megaptera novaeangliae, with the valuable North Pacific right whale, Eubalaena japonica, also pursued opportunistically. Catch data are grossly incomplete for most stations; no logbooks were kept for these operations as they were for high-seas whaling voyages. Even when good information is available on catch levels, usually as number of whales landed or quantity of oil produced, it is rarely broken down by species. Therefore, we devised methods for extrapolation, interpolation, pro rationing, correction, and informed judgment to produce time series of catches. The resulting estimates of landings from 1854 to 1899 are 3,150 (SE = 112) gray whales and 1,637 (SE = 62) humpback whales. The numbers landed should be multiplied by 1.2 to account for hunting loss (i.e. whales harpooned or shot but not recovered and processed).

Smith A.B.,University of California at Berkeley | Smith A.B.,Missouri Botanical Garden | Santos M.J.,The History Project | Koo M.S.,University of California at Berkeley | And 6 more authors.
Ecography | Year: 2013

Species distribution models (SDMs) are commonly applied to predict species' responses to anticipated global change, but lack of data from future time periods precludes assessment of their reliability. Instead, performance against test data in the same era is assumed to correlate with accuracy in the future. Moreover, high-confidence absence data is required for testing model accuracy but is often unavailable since a species may be present when undetected. Here we evaluate the performance of eight SDMs trained with historic (1900-1939) or modern (1970-2009) climate data and occurrence records for 18 mammalian species. Models were projected to the same or the opposing time period and evaluated with data obtained from surveys conducted by Joseph Grinnell and his colleagues in the Sierra Nevada of California from 1900 to 1939 and modern resurveys from 2003 to 2011. Occupancy modeling was used to confidently assign absences at test sites where species were undetected. SDMs were evaluated using species' presences combined with this high-confidence absence (HCA) set, a low-confidence set in which non-detections were assumed to indicate absence (LCA), and randomly located 'pseudoabsences' (PSA). Model performance increased significantly with the quality of absences (mean AUC ± SE: 0.76 ± 0.01 for PSA, 0.79 ± 0.01 for LCA, and 0.81 ± 0.01 for HCA), and apparent differences between SDMs declined as the quality of test absences increased. Models projecting across time performed as well as when projecting within the same time period when assessed with threshold-independent metrics. However, accuracy of presence and absence predictions sometimes declined in cross-era projections. Although most variation in performance occurred among species, autecological traits were only weakly correlated with model accuracy. Our study indicates that a) the quality of evaluation data affects assessments of model performance; b) within-era performance correlates positively but unreliably with cross-era performance; and c) SDMs can be reliably but cautiously projected across time. © 2013 The Author. Ecography © 2013 Nordic Society Oikos.

Tinjod N.,The History Project
European Space Agency Bulletin | Year: 2015

The 40th anniversary of the signing of the Convention for the creation of a single European Space Agency (ESA) in May 1975 was celebrated in May 2015. The idea of building an independent space capability in Europe dated back to the early 1960s when six European countries, such as Belgium, France, Germany, Italy, the Netherlands and the United Kingdom, formed the European Launcher Development Organization (ELDO) to develop a heavy launcher, called 'Europa'. The ESA Convention, which broadened the scope of the new agency's remit to include operational space applications systems, was opened for signature until December 31, 1975. The ESA Convention entered into force on 30 October 1980, with the deposit of the last instrument of ratification by France, after being signed at the European Space Conference in Paris on 30 May 1975 by the representatives of the European Space Research Organization (ESRO) and ELDO member States.

Wright D.,The History Project
Space Policy | Year: 2012

The UK government appears to be taking space more seriously, even if funding for the sector remains limited. Speeches and attendees at the conference confirm this trend, with a particular emphasis on innovation and a general sense that prospects for the UK space industry are good. The various themes and highlights of the conference are discussed. © 2012 .

The History Project | Date: 2013-09-03

printed educational materials, namely, workbooks and handouts in the fields of history and science.

The History Project | Date: 2011-03-25

Printed educational materials, namely, books, magazines, workbooks and handouts in the fields of history and science.

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