Open Space Advisory Board Agenda and Packet 2017 08 09

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Marsden (1999) stated that a reasonable number of detections are required for adequate analysis. Buckland et al. (1993) recommended at least 60-80 detections be required for fitting the detection function in program DISTANCE. Numbers lower than 60 may be vulnerable to stochastic factors such as a total of 20 detections of one species all occurring very close to the point; this `spike' in sighting distance would be problematic in analysis. If the data are of high quality, then reliable estimates may be possible for smaller detection samples (Rosenstock et al., 2002). The lone point count station was located on the southeast corner of the pond/wetland located near the center of Coyote Run Open Space (Figure 2). Although line transects can provide advantages over fixed radius point counts, point counts are more applicable in situations where auditory detections will be incorporated into the analysis, such as in denser habitats where a bird may be heard but not visible. Counts were conducted at this location for 10 minutes. The linear distance from the observer to each bird detected was measured. All surveys were conducted from 30 minutes before sunrise until no later than 7:00 AM to maximize survey time during periods of high avian activity (Buskirk and McDonald, 1995; Sogge et al., 1997). Surveys were conducted on June 20, 2017 at Daughenbaugh and Warembourg Open Spaces; surveys were conducted June 22, 2017 at Coyote Run. 3. Environmental Setting The three Open Space properties have all been converted from native shortgrass prairie into agricultural lands (likely both as rangeland or dryland/irrigated farming) and there is no native habitat present. All surrounding lands are modified as well with commercial and residential development, roads. Irrigation ditches and stormwater drainage structures provide aquatic and riparian habitat where none originally occurred. A description of each property is provided below: 3.1. Coyote Run Open Space Most of Coyote Run is dominated by the non-native invasive grass smooth brome (Bromus inermis) (Photo 1). There are small drainages in which willows (Salix sps.) occur along with plains cottonwood (Populus deltoides) and chokecherry trees (Prunus virginiana) (Photo 2). A pond/wetland occurs near the center of the property that is dominated with cattails (Typha sps.) and rushes. The habitat is much more diverse on the east side of the property with small ditches present and more vertical structure with greater plant diversity than the remainder of the property. 3.2.Daughenbaugh Open Space Daughenbaugh Open Space is dominated by the presence of black -tailed prairie dogs (Cynomys ludovicianus). There are varying reports of the effects of prairie dogs on faunal diversity. Recently, Cully et al. (2010) reported small mammal species richness and evenness are less variable within colonies, and Pruett et al. (2010) reported species diversity and evenness greater in areas outside of colonies. This decrease in species richness and evenness within colonies could be in part a result of the change in plant species composition (often towards a non-native invasive community) and a suppression of plant cover by prairie dogs (Baker et al. 2013). The response to lower plant diversity is seen in the avian community as well. The dominant plant species is the non-native field bindweed (Convolvulus arvensis). At the eastern edge of the southern transect (Figure 3 — DAU01 Photo 3) there are a number of boxelder (Acer negundo) trees which provide species and structural diversity to the landscape. In addition to the trees there are large common mullein (Verbascum thapsus) interspersed with cheatgrass (Bromus tectorum) and crested wheatgrass (Agropyron cristatum), all of which are non-native and the first two are invasive. The diversity of the Open Space in general is increased because of the presence of the Goodhue Ditch which provides foraging habitat for species such as swallows. 6 13