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Satellite-measured SO 2 mass loadings and ground-based measurements of SO 2 emission rate are not directly comparable, with ~ 40% differences between mean emissions reported by each technique from Tungurahua volcano, Ecuador, during late 2007. Numerical simulations of post-emission processing and dispersal of Tungurahua's SO 2 emissions enable more effective comparison of ground- and satellite-based SO 2 datasets, reducing the difference between them, and constraining the impact of plume processing on satellite SO 2 observations. Ground-based measurements of SO 2 emission rate are used as the model input, and simulated SO 2 mass loadings are compared to those measured by the Ozone Monitoring Instrument (OMI). The changing extent of SO 2 processing has a significant impact on daily variation in SO 2 mass loading for a fixed volcanic emission rate. However, variations in emission rate at Tungurahua are large, suggesting that overall volcanic source strength and not subsequent processing is more likely to be the dominant control on atmospheric mass loading. SO 2 emission rate estimates are derived directly from the OMI observations using modelled SO 2 lifetime. Good agreement is achieved between both observed and simulated mass loadings (~ 21%), and satellite-derived and ground-measured SO 2 emission rates (~ 18%); a factor of two improvement over the differences found by simple direct comparison. Whilst the balance ofemission source strength and post-emission processing will differ between volcanoes and regions, under good observation conditions and where SO 2 lifetime is ~ 24 hours, satellite-based sensors like OMI may provide daily observations of SO 2 mass loading which are a good proxy for volcanic source strength.
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A breeding moratorium enacted in the early 1980s for African lions Panthera leo in North American zoos was lifted in 1998. However, post-moratorium reproduction was poorer than expected from 1999 to 2005. In 2007, therefore, a multi-institutional survey was conducted to provide a general overview of the Species Survival Plan® (SSP) African lion population ??, and assess relationships between social, management, husbandry and environmental conditions, and reproductive activity. Females (n?=?40) were divided into reproductive categories: contracepted, non-reproductive, nulliparous and reproductive. Several factors were associated with reproductive success, one of which suggests that larger pride sizes and lion temperament may play roles in reproduction. In addition, compared with reproductive ??, non-reproductive ?? were housed with fewer ??, were fed less food per day, spent less time per day on display and tended to be trained fewer times per week. The biological significance of some of these relationships with reproduction is not clear, and cause-and-effect relationships were not established. However, this information will be valuable in directing future studies to determine how lion management affects reproduction. One possible explanation for the reproductive decline could have been a loss of breeding-management knowledge during the moratorium, a situation that has since been resolved.
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Two new species of Goniasteridae, Astroceramus eldredgei n. sp. and Apollonaster kelleyi n. sp. are described from the Hawaiian Islands region. Prior to this occurrence, Apollonaster was known only from the North Atlantic. The Goniasteridae is the most diverse family of asteroids in the Hawaiian region. Additional in situ observations of several goniasterid species, including A. eldredgei n. sp. are reported. These observations extend documentation of deep-sea corallivory among goniasterid asteroids. New species occurrences presented herein suggested further biogeographic affinities between tropical Pacific and Atlantic goniasterid faunas.
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NMNH
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Peer-reviewed
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The kiwi, indigenous to New Zealand, is a small flightless bird that is unique in the avian world. Detailed studies in kiwi behaviour are limited because of the nocturnal nature of the species. In this study, two juvenile Brown kiwi Apteryx mantelli chicks were monitored using a video camera for about 24 hours over a period of 2 months. Primarily, this study focused on the budgeting of 26 distinct behaviours during different time periods. Many of the behaviours, such as feeding , drinking and probing , had similar totals, compared with other behaviours, such as aggression , stretching body and jumping , which were predominantly expressed by one individual. Certain behaviours, such as pacing , running and jumping , were often seen more frequently at certain time periods. Territoriality, including changes pertaining to the individual and their size of territory, was also noted as the observations progressed. This study provides a better understanding of the behaviour of Brown kiwi chicks in terms of budgeting different behaviours and interactions between juvenile ??.
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Peer-reviewed
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Peer-reviewed
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Peer-reviewed
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Peer-reviewed
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