47 resultados para Read, Guy Martin


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1. The rapid expansion of systematic monitoring schemes necessitates robust methods to reliably assess species' status and trends. Insect monitoring poses a challenge where there are strong seasonal patterns, requiring repeated counts to reliably assess abundance. Butterfly monitoring schemes (BMSs) operate in an increasing number of countries with broadly the same methodology, yet they differ in their observation frequency and in the methods used to compute annual abundance indices. 2. Using simulated and observed data, we performed an extensive comparison of two approaches used to derive abundance indices from count data collected via BMS, under a range of sampling frequencies. Linear interpolation is most commonly used to estimate abundance indices from seasonal count series. A second method, hereafter the regional generalized additive model (GAM), fits a GAM to repeated counts within sites across a climatic region. For the two methods, we estimated bias in abundance indices and the statistical power for detecting trends, given different proportions of missing counts. We also compared the accuracy of trend estimates using systematically degraded observed counts of the Gatekeeper Pyronia tithonus (Linnaeus 1767). 3. The regional GAM method generally outperforms the linear interpolation method. When the proportion of missing counts increased beyond 50%, indices derived via the linear interpolation method showed substantially higher estimation error as well as clear biases, in comparison to the regional GAM method. The regional GAM method also showed higher power to detect trends when the proportion of missing counts was substantial. 4. Synthesis and applications. Monitoring offers invaluable data to support conservation policy and management, but requires robust analysis approaches and guidance for new and expanding schemes. Based on our findings, we recommend the regional generalized additive model approach when conducting integrative analyses across schemes, or when analysing scheme data with reduced sampling efforts. This method enables existing schemes to be expanded or new schemes to be developed with reduced within-year sampling frequency, as well as affording options to adapt protocols to more efficiently assess species status and trends across large geographical scales.

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Quite a few texts from England were translated into Irish in the fifteenth and early-sixteenth centuries. The number of these texts was significant enough to suggest that foreign material of this sort enjoyed something of a vogue in late-medieval Ireland. Translated texts include Mandeville’s Travels, Guy of Warwick, Bevis of Hampton, Fierabras and a selection of saints’ lives. Scholars have paid little attention to the origins and initial readerships of these texts, but still less research has been conducted into their afterlife in early modern Ireland. However, a strikingly high number of these works continued to be read and copied well into the seventeenth century and some, such as the Irish translations of Octavian and William of Palerne, only survive in manuscripts from this later period. This paper takes these translations as a test case to explore the ways in which a cross-period approach to such writing is applicable in Ireland, a country where the renaissance is generally considered to have taken little hold. It considers the extent to which Irish reception of this translated material shifts and evolves in the course of this turbulent period and whether the same factors that contributed to the continued demand for a range of similar texts in England into the seventeenth century are also discernible in the Irish context.