3 - The Bowery_PUBLIC COMMENT_RAMSEY

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5.0 Environmental Analysis 5.2 Biological Resources Avion Project SEIR Page 5.2-5 currently supports an active gopher population that is present throughout the habitat. This level of gopher activity confined to a relatively small area creates conditions that are not suitable for plants that grow from bulbs or corms. • Low Plant Species Composition – The existing non-native grassland areas on the site are comprised of dense stands of non-native grasses almost to the complete exclusion of other plant species. No plant species from bulbs or corms occur in the grassland on the site. This condition is in sharp contrast to the Heritage Brodiaea Preserve where the less dense grassland (i.e., lower thatch development) habitat on heavy clay soil supports bulb and corm species such as thread-leaved brodiaea, blue-eyed grass, blue dicks, death camas, and goldenstar in relatively large numbers. • Lack of Clay Soil – Thread-leaved brodiaea in San Diego County occurs primarily on clay soils that are moist during the spring, typically derived from granitic rock, and that support native grassland, annual grasslands, alkali grasslands, or open sage/chaparral scrub habitats (U.S. Fish and Wildlife Service [USFWS] 1998, 2005). The species may also occur on soils with a clay subsurface, or clay lenses within loamy, silty loam, loamy sand, silty deposits with cobbles, or alkaline soils. The Avion site occurs on shallow San Miguel-Exchequer rocky silt loam soils derived from meta-volcanic rock. The brodiaea population within the Heritage Preserve to the north occurs solely on Auld clay soils. This Auld clay soil lens does not extend onto the Avion site. • Past Surveys – Thread-leaved brodiaea was not observed on the project site during a past biological survey conducted on the site in 2013 (RECON 2013). Numerous other surveys conducted over the last five years of the adjacent land to the north where the Heritage Bluffs II and East Clusters development projects are located did not find thread-leaved brodiaea in close proximity to the southern boundary of the Avion project site. c. Sensitive Wildlife Species Two sensitive wildlife species were observed during the survey. A Cooper’s hawk (Accipiter cooperii) was observed flying over the project site. A nest of the San Diego desert woodrat was observed in the chaparral vegetation. The woodrat nest is located in dense chaparral in the northeastern portion of the project site to the east of the drainage course (see Figure 5.2-1). Four other sensitive species have a moderate potential to occur on the project site due to the habitat conditions. Two sensitive reptile species, Belding’s orange-throated whiptail (Aspidoscelis hyperythra beldingi) and coastal whiptail (Aspidoscelis tigris stejnegeri), may occur in small numbers in the shrub land habitats on the project site. Two sensitive bird species, coastal California gnatcatcher (Polioptila californica californica) and southern California rufous-crowned sparrow (Aimophila ruficeps canescens), have the potential to occur in small numbers in the coastal sage scrub and southern mixed chaparral areas on the project site. A list of sensitive wildlife species with the potential to occur on the site is provided in Appendix B - Attachment 4. A habitat assessment for the potential for the site to support western burrowing owl (Athene cunicularia hypugaea) was conducted during the general survey of the site. It was determined that there is a low potential for this species to occur on-site, as the non-native grassland present is likely