|
|||||
|
|
Tree-cavity occurrence, cavity occupation and reproductive performance of secondary cavity-nesting birds in oak forests: The role of traditional management practices |
|
| Authors: | Hugo Robles Carlos CiudadErik Matthysen |
| Institution: | a Evolutionary Biology Group (GIBE), Faculty of Sciences, University of A Coruña, Campus Zapateira, E-15008, A Coruña, Spain b Evolutionary Ecology Group (EVO-ECO), Department of Biology, University of Antwerp, Middelheimcampus, Groenenborgerlaan 171, BE-2020, Antwerp, Belgium c Department of Biodiversity and Environmental Management, University of León, Campus de Vegazana s/n, E-24071, León, Spain |
| Abstract: | Secondary cavity-nesting birds (SCN), which cannot create their own breeding cavities, are expected to be influenced by habitat alteration caused by forest management practices, but the mechanisms underlying the distribution pattern of SCN subjected to different management systems are poorly known. To improve our knowledge on these mechanisms, we examine cavity abundance, cavity occupation and reproductive performance of SCN in Pyrenean oak (Quercus pyrenaica) forests subjected to two management systems: (i) dense “young forests”, maintained at such stage by clear-cuttings and burns, and (ii) “old forest”, subjected to extensive traditional grazing and scarce firewood extraction by selective cutting. Young forests had considerably lower density of cavities (1.29 ± 0.71 vs 15.09 ± 2.00 cavities ha−1), SCN species (0.18 ± 0.11 vs 0.61 ± 0.07 species ha−1) and nests (0.40 ± 0.27 vs 2.67 ± 0.25 nests of all SCN ha−1) than old forests, indicating that a low availability of cavities may limit SCN assemblages in young oak forests. However, reproductive parameters of great (Parus major) and blue (Cyanistes caeruleus) tits associated with the availability of food (laying date, clutch size, nestling number and weight, adult weight) did not differ between both forest types, suggesting that food supply was not reduced in young forests, at least for tits during the breeding season. Large diameter (up to 170 cm dbh) decayed trees were the most likely to hold cavities, but birds preferred smaller living cavity-trees for nesting (90% of nests in 21-65 cm dbh trees). The preservation of cavity-trees within traditionally managed old oak forests is crucial in providing nesting opportunities to SCN. Besides, the protection of these traditionally managed forests would also benefit to other forest organisms that depend on old and open oak forests. |
| Keywords: | Cavity-nesting birds Cavity occupation Dehesa Traditional management Quercus pyrenaica Reproductive performance |
| 本文献已被 ScienceDirect 等数据库收录！ | |