Recovery Plan for the Northern Spotted Owl - DRAFT

Summaryspores (Maser et al. 1978b). Mushrooms also are consumed which complimentsspore dispersal by wind. The functional role of mycorrhizal fungi inconiferous forests has been described by Trappe and Fogel (1977) and theircharacterization of this role is quoted below:"The great majority of vascular plants have evolved to a dependenceon mycorrhizae as the most metabolically active parts of their rootsystems. Most woody plants require mycorrhizae to survive, andmost herbaceous plants need them to thrive. Despite their relativelysmall biomass, the mycorrhizal fungi (mycobionts) are vital foruptake and accumulation of ions from soil and translocation tohosts because of their high metabolic rate and strategically diffusedistribution in the upper soil layers. The mycobionts produceenzymes, auxins, vitamins, cytokinins, and other compounds thatincrease rootlet size and longevity. They commonly protect rootletsfrom pathogens. They absorb and translocate water to the host.Most mycobionts, in turn, depend on their hosts for carbon products.Except for orchid mycobionts, few are capable of decomposingorganic matter, although their respiration contributes significantlyto evolution of carbon dioxide from soil. The fungal mycelium andsporocarps are sources of accumulated nutrients and energy fordecomposers and consumers. Nutrients and carbon can be transferredfrom one vascular plant to another by a shared mycorrhizalmycelium. The several thousand species of fungi believed to formmycorrhizae encompass great physiological diversity. They differ innumerous ways, including degree of host specificity, resistance toenvironmental extremes, selectivity in ion uptake, and production ofbiologically active products. Net effects of one mycobiont on a hostcan differ from those of another, although overall functions areshared by most. As key links in below ground nutrient and energycycling, mycorrhizae and their mycobionts can be ignored only atsubstantial peril of reaching unreal conclusions about ecosystemprocesses."This explanation gives some sense of the importance of fungi in the function ofconiferous forests. In addition, two of the spotted owl's primary prey species(northern flying squirrel and red-backed vole) consume fungi as their primaryfood (Maser et al. 1978b), so that fungi are an important link in the owl's foodchain.Three hundred and sixty-four species of plants and animals were considered inthe recovery planning process for the northern spotted owl (Table D.9). Ofthose, five are listed federally as threatened or endangered, more than 150 arecandidates for listing; 30 are listed as threatened or endangered in one or moreof the three states, and 131 are "species of special concern" in at least one ofthe states. In addition, the list of 28 fish species includes approximately 766stocks that are considered at risk and may become candidates for listing in thefuture. More than 100 of the species are narrowly or broadly endemic to thePacific Northwest and 194 are associated with older forests. The large numberof candidates for federal listing, species of special concern, and endemicspecies emphasizes the importance of considering other species in the owlrecovery plan. In addition, the large number of riparian associated species(132), plus the number of fish stocks at risk emphasize the importance ofriparian areas.364