Retention trees, preservation of deadwood in forest work, controlled burning and other nature management measures promote the survival of many endangered species. Nature management in commercial forests is a cost-effective method of enhancing biodiversity in forests.
The conservation status of various species is evaluated every ten years in Finland, with the most recent report, Punainen kirja (Red Book), published in December 2010. Unlike other species groups, the conservation status of birds and mammals was re-evaluated during 2015. Research on birds and mammals generates new data at a faster pace than for most other species groups, thus enabling a more frequent evaluation of their conservation status. There is a good deal of general interest on birds and mammals, which makes it even more essential to keep the information on their conservation status up to date.
Some 50,000 species exist in Finland, of which 21,398 are known well enough to evaluate their conservation status. The 2010 report defines 2,247 Finnish species as endangered. In other words, approximately one in ten species is endangered. Thirty-six percent of these species live in forests and 23 percent in different cultural or heritage environments. The high number of forest species is partly explained by the fact that roughly half of all Finnish species inhabit forests.
Many forest species are under particular threat because of the relatively low quantity of deadwood in Finnish forests currently. Other threats are the decline of herb-rich forest areas and of deciduous trees. Elsewhere, species living in open forest habitats, such as esker areas, are hampered by overgrowth.
Retention trees and controlled burning
The 2010 report shows that forest species are becoming endangered at a slightly slower rate than previously, and for many species, the trend has been even positive. Around half of these are beetles, which benefit from retention trees left on harvesting areas, particularly aspen.
Heteroptera bugs are now less endangered and bug species inhabiting forest fire areas seem to benefit from increased controlled burning. The subspecies aradus signaticornis has been downgraded from endangered into the category of least concern because the population has grown healthier over the last ten years.
Thirteen forest bird species were shifted from the near threatened category into the category of least concern in the 2010 report. The 2015 report states that the number of both endangered and red list category species is considerably lower in species living in forest habitats, compared to the averages of all species generally.
Conservation status evaluations show that retention trees, preservation of deadwood, controlled burning and other nature management measures seem to promote the survival of many endangered species. All this clearly indicates that nature management of our commercial forests has a real impact on promoting the biodiversity of our woods. And it is cost-effective! Burning of retention tree groups is a good example of a nature management method able to produce biodiversity benefits rapidly while requiring fewer financial resources.