Seguimiento biológico de Paíño Europeo (Hydrobatespelagicus) y Pardela Cenicienta (Calonectris diomedea) en la Región de Murcia. 2008.

Abstract

A biological monitoring of Procellariiformes birds has been carried out in some islands within the Region of Murcia during 2008. The two target species are the European storm petrel (Hydrobates pelagicus) and Cory’s shearwater (Calonectris diomedea), and the islands are Hormigas and Las Palomas. Among our objectives are to estimate the population size of both species and to determine breeding parameters. We have carried out two nighttime field visits to Hormigas and three to Las Palomas, from April to July, in order to sample adult birds (capture and ringing), and two daytime field visits to Hormigas and four to Las Palomas, from August to November, to monitor chicks. We have estimated these birds’ populations by applying different methods, and we have compared such estimates with previous results. In addition, capture rates have been calculated. For monitoring of breeding pairs, we looked for adult birds during the incubation period, marking and numbering nests for subsequent checks. A total of 741 captures of European storm petrel have been collected. In Hormigas, by applying two methods, a population of 426-1,753 bird individuals have been estimated. In Las Palomas, by applying three methods, estimated values range from 992 to 3,008 individuals. Concerning Cory’s shearwaters, the highest estimated value is 88 pairs, although the Southern cliff has not been monitored for being dangerous, which would increase their population. Obtained values differ between different methods or between different samples within the same method, as it happened in previous years. Altogether, 27 storm petrel nest sites (22 in Hormigas and 5 in Las Palomas) and 33 Cory`s shearwater nest sites have been monitored. The obtained breeding parameters are either similar to those of other studied colonies or better.