Can protected areas buffer short-term population changes of resident bird species in a period of intensified forest harvesting?

Abstract

Protected areas (PAs) should maintain populations of focal species, but their ability to achieve this target is affected both by land use outside PAs and by climate warming. To study effects of land use on species and ability of PAs to maintain populations of species, we compared trends in abundance of 15 resident bird species between two periods of relatively stable and increasing logging volume in boreal forests in Finland, in 2006–2011 and 2012–2018, respectively. We studied trends in abundance of forest birds in unprotected areas and in PAs, where logging is not allowed. In general, patterns of population changes did not differ between PAs and unprotected areas. Abundances of ten of the 15 species were, however, concentrated in southern Finland, where PAs have low coverage, and where trends in abundance merely reflect changes in unprotected areas. Five species declined, and they all probably suffered from the effects of increased logging. Four of them had a southern distribution in Finland, so they should even benefit from the rapid climate warming occurring in these regions. In northern Finland, PAs cover a much higher proportion of land than in southern Finland, and thus PA network may better maintain populations, which was also reflected in more stable populations of species therein. For populations to persist in PAs and for PAs to buffer against environmental changes, a PA network should have a high level of coverage as in northernmost Finland thus supporting Aichi Target 11.