Recovery Plan for the Northern Spotted Owl - DRAFT

Table B.4. Abundance of snags and logs in habitats used by northern spotted owlsin the Klamath and California Coast provinces.Nest Nest Roostl OldFeature Province Inches Site Stand Roost Forage Forage GrwothSnags: California Coast >5 Oa Oa 1 b 3ano./ac. by -ok -okdbh classKlamath >5 22c1 6 d 1 ge 1 6 9 1 9 d 18e 1 7 h 2130' 33 f 34 f 35!>20 5d 2g 3d 2 h 4i2' 2' 2f 310-10 20111-18 2>18 4Logs: no. ac California Coast >10 59a 456 53a 47 bby diameterat large end Klamath >10 55c 29f 31' 32l>20 10 8 35f 12h 23'10 8apious (1989)bKerns (1989)CSelf, (pers. comm.)dSolis (1983)esisco and Guilerrez (1984)fBingham et al. (1991)gChavez-Leon (1989)hJimerson et al (1991a)'Jimerson et al. (1991b)JAsrow (1983)kDiller and Folliard, (pers. comm.)Discussiontotal canopy cover in roosting and foraging sites averaged 47 percent in sixhome ranges (Benson 199 lb).Only a few studies have reported snag densities (Table B.9) but densitiesappeared to be approximately similar in nest sites, nest stands, foraging androosting sites, and old-growth stands, except that fewer medium and largesnags were present in the eastern Washington Cascades province.Log densities were similar in nest sites and old-growth sites in the westernWashington Cascades (Hamer pers. comm., Spies et al. 1988).Hardwoods were rare or absent in utilized sites in the western WashingtonCascades, Olympic Peninsula, and eastern Washington Cascades (Allen et al.1989, Forsman and Benson pers. comm., Hamer pers. comm.).The main results of this analysis were as follows. Average canopy cover washigh (more than 80 percent) in all studies except those in the eastern WashingtonCascades where average cover was lower at nest sites and much lower atroosting and foraging sites. The average number of trees/acre by dbh classwas fairly consistent among studies, except that fewer large trees occurred inthe eastern Cascades (in both Washington and California) and in the western297