¿Tuvieron efecto los tratamientos químicos contra los topillos?: inferencia a partir del estudio de la dieta de la lechuza común y censos de rapaces diurnas

The Junta de Castilla y León carried out several campaigns of control of common vole (Microtus arvalis) from 2007 to 2009, which coincided with a demographic explosion of the species. Anticoagulants products like chlorophacinone and bromadiolone were used during these campaigns. Information on the t...

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Bibliographic Details
Main Author: Jubete Tazo, Fernando
Format: Article in Journal/Newspaper
Language:Spanish
Published: Universidad de Málaga (UMA): Sociedad Española para la Conservación y Estudio de los Mamíferos 2011
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Online Access:https://dialnet.unirioja.es/servlet/oaiart?codigo=3862463
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Summary:The Junta de Castilla y León carried out several campaigns of control of common vole (Microtus arvalis) from 2007 to 2009, which coincided with a demographic explosion of the species. Anticoagulants products like chlorophacinone and bromadiolone were used during these campaigns. Information on the treatment campaigns which used rodenticides was compared with two studies which had been carried out to estimate me abundance of common vole, so as to evaluate the effectiveness of such treatments on the control of Microtus arvalis populations. The first study is based on the percentage of Microtus arvalis in barn-owl (Tyto alba) diet and the second by making road transects to find the abundance of diurnal birds of prey. Sixteen batches of barn-owl pellets were analysed -one each trimester, between January 2006 and december 2009- and 3,964 items of prey were idencified. 96.3% of them were micromammals of seven species, and 63.7% were common vole. The percentages of Microtus arvalis / trimester varied from 18.0% -after the collapse of a áemographíc explosion- to 96.4% at the demographic explosion's peak. These results made it possible to detect two demographic explosions, one starting at me beginning of the second trimester of 2006 and finishing in the second trimester of 2008. The second started at the second semester of 2009 and it seemed to enter a collapse stage at me end of the same year. On the road, 5,387 birds of prey of fifteen different species were counted from January 2005 to December 2009. This is a monthly Kilometric Abundance Index average of 69.0 individuals/lOO km. The data showed that peaks of abundance ofbirds of prey coincided in time with both common vole demographic explosions. Nevermeless, the period considered for each demographic explosion was significantly shortened. According to me bird data, the first eycle started in July 2006 and continued until February 2007. The second cycle started in May 2009 and continued until December 2009. Bom studies reveal me ineffectiveness of the chemical ...