Vedboende biller i de kommunale skove Biodiversitet i skov – fokus på arter og processer

1. Vedboende biller i de kommunale skove Biodiversitet i skov – fokus på arter og processer Hans Peter Ravn hpr@ign.ku.dk Sektion for Skov, Natur og Biomasse ”Kommunale biller” versus andre biller Hvorfor? Hvad er vi oppe imod? Populære biller/upopulære biller! Biller som organismegruppe – De mest diverse! De sjældneste – biller knyttet til gl skov Kan det lade sig gøre i kommunale skove  ?! AHA-metoden Dødt ved på mange måder – kun fantasiien sætter grænser!

3. Coleoptera – den formrigeste organismegruppe!

4. Kommunerne forvalter arealer, der repræsenterer meget forskelligartede naturtyper – ud over skovene: enge, kær, søer, åer, overdrev, vejrabatter, strandoverdrev, klitter, heder –og kulturarealer med mere eller mindre grønt islæt: idrætsanlæg, fælleder, bygnigsomgivelser Der indgår mangesidige hensyn i kommunal naturforvaltning: Rekreative interesser, sport og idræt, kulturhistoriske værdier, lokalt særpræg, biodiversitets hensyn og økonomiske hensyn ”Kommunale biller” versus andre biller

5. Vi har forpligtet os [Rio 1992, Johannesburg 2004, Nagyoa 2010 og EU’s biodiversitetsstrategi 2011-20] • Økonomiske fordele ”The befitsthat human population derive, directly or indirectly, from ecosystemfunctions” (Bolund and Hunhammer 1999) • Provisioning services – fx føde og ferskvand • Regulating services – fx lokal klima, luftkvalitet, kulstofbinding, regnvandstilbageholdelse og bestøvning • Habitat or supporting services – fx levesteder for planter og dyr • Cultural services – fx rekreation, mental helse, æstetiske oplevelser (The Economics of Ecosystems and Biodiversity, 2011) Hvorfor biodiversitet?

6. Efficient utilisation of all ressources => diversity • Biomass per areal: • Birds: 1-2 kg/ha Large mammals: 2 kg/ha Small mammals: 5 kg/ha Canopy insects: 100kg/ha Soil fauna: 1-2 t/ha The trees: 3-400 t/ha • Seeds: Lepidoptera, Coleoptera, Hymenoptera Diptera • Buds and shoot tips: Lepidoptera Coleoptera • Leaf eaters: Lepidoptera Coleoptera, Hymenoptera, Diptera, Orthoptera • Sapfeeders. Hemiptera(aphids, feaf-hoppers, plant bugs) • Bark: Coleoptera, Hemiptera • Wood-living: Lepidoptera, Coleoptera Hymenoptera • Roots: Coleoptera, Hemiptera

7. Danish red list species distributed on species and forest habitat type • RE CR VU NT • IN ALL, FOREST • Forest edges • Old forest • Broadleaved • Conifers • Swamp forest • Untouched forest • Wood material

8. Forest & Landscape Red list conclusion 2010 • ”The largest group og endangered species - every five – are forest species. From this group every third species is either disappeared or endangered”

10. Saproxylic insects (dead wood dependant) • Coleoptera – beetles • In Sweden: 4.650 – saproxylics: 1.075 • Hymenoptera – wasps, ants and bees • In Sweden: 8.000 – saproxylics:>1.500 • Diptera – flies, midges and craneflies • In Sweden: 7.000 – saproxylics: ca 1.000 • (from Sörensen 2008)

11. Tree species, native herbivore species • Denmark, beetle species • Oak conif. Salix Betula Fagus PopulusCherry Ash Elm Tilia Acer Carpinus Sorbus Horse-chestnut

12. Forest & Landscape Tree species, native herbivore insect species • Sweden • GB • Salix • Betula • Oak • Prunus spin. • Populus • Cratategus • Pinus • Malus • Alnus • Picea • Ulmus • Fagus • Coryllus • Sorbus • Tilia • Fraxinus • Carpinus

13. Adminitrator choise: Tilia Sorbus Quercus Fraxinus Acer Platanus Fagus Carpinus Bird-Cherry Ulmus Populus Others Horse-Chestnut Betula Conifers Salix (Thomas Randrup) Coleopterists choise: Quercus Fagus Ulmus Sorbus Populus Betulus Fraxinus Salix Pinus Tilia Bird-Cherry Carpinus Acer Picea Horse-chestnut Platanus (Palle Jørum) Tree species selection – the most popular • Macro lepidoptera, specific tree choise: • Salix – 87 • Betula – 60 • Populus – 40 • Fagus – 34 • Quercus – 22 • Alnus – 22 • Picea – 16 • Pinus - 15 • Ulmus – 11 • Tilia – 10 • Fraxinus – 8 • Larix - 4 • Acer – 3 • Bird-cherry – 3 • Horse-Chestnut – 2 • Sorbus – 4 • Acer pseupl. – 1 • (Per Stadel Nielsen)

14. 13 tree species estimated relative importance for four groups of organisms • Tree species mychorrhiza polypore fungi insects nesting birds • Betula Quercus pe Fagus silv Salix sp Alnus sp. Larix sp. Pinus syl. Ulmus gla. • Pseudotsu • Picea abies Fraxinus Abies sp Acer sp • Betula Quercus pe Fagus silv Salix sp Alnus sp. Larix sp. Pinus syl. Ulmus gla. • Pseudotsu • Picea abies Fraxinus Abies sp Acer sp • (Flemming Rune, mycologist)

15. Birds food ressource on 8 common tree species, Strødam • Mobile - sessile • Sessile vers. mobile species • Drymatter insects – microgram/squaremeter leaf • Betula pub. Quercus pend. Alnus r. Sambucus Fraxinus Salix Picea abies Fagus sylv. • (Karsten Laursen, pers. comm.)

18. Keep surface natural

19. Old traditional growing practises may increas diversity • Coppice (Stævningsdrift) • Willow production, bocage

20. Important messages • Save continuity in tree species selection • Save continuity in in age distribution and degree of degradation – both standing and horizontal dead wood • Save stumps (low and high) both broadleaved and conifers • Transitions between closed stands and open land are particular species rich and should have particular attention

21. Brand - betydningen • Fire creates a quite particular flora and fauna

22. Fauna succession in deadwood • The first short fase (1-2 years) is dominated by barkliving insects: barkbeetles, weevils and longhorned beetles. Only few red listed species are among these

23. Fauna succession in deadwood • 2nd fase is longer dominated by species that lives under the bark and in the sapwood. Fungi abundant. Bark loosen and begin to fall off. More species feeds on the central wood. Some redlisted species.

24. Fauna succession in deadwood • 3rd fase. Several decenniums. Bark gone. Many rare and red listed species. Click-beetles, fungivores and predators

25. 4th fase. Shelter more than food. Ground living insects, millipedes, slugs and snails Fauna succession in deadwood

26. Forest & Landscape

27. Forest & Landscape Veteran tree

28. Forest & Landscape

30. Forest & Landscape Mikael Sörensens AHA-method • A method for identification of single tree conservation priority as a function of teir probablity of keeping redlisted saproxylic insect species • Class I: two A - Highest conservation priority (~100%) • Class II: one A or four B -High conservation priority (~50%) • Class III: two B - Of some conservation priority (~10%) • Class IV: one or no B - Low priority (~0%) • Class R: Resource tree - Older, healthy, undamaged trees