2016-09-06_GENERAL DOCUMENTS - M1977141

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No NLF activity confirmed after nearly weekly visits over five months. Flood-related heavy clay erosional deposits from the hillside may have impacted the site, as even the tiger salamander population appears to have diminished significantly. Flood deposited predaceous fish species are observed in the pond. 2015- Survey Summary: No NLF detected with several site visits. Documented persistence of predatory fish, Emergent vegetation rebounding, beaver presence in pond and general area. 2016- Survey Summary: No NLF observed after several site visits. Amphibians detected in shoreline vegetation but identification not possible, no tiger salamanders observed, predatory fish still present. Surveys on 5/9, 5/25 and every 2-3 weeks until August 1, also surveyed a temporary, seasonal pond at Hall Ranch during late June and early July (no NLF). Bat Discussion: Hall HAggregate Mine Site- Use by Bat Species.- Survey History of Hall II for use by bats- conducted by Dr. Rick Adams, University of Northern Colorado. Dr. Adams has conducted research on bats throughout Boulder County for 18 years. In 2013, BCPOS requested that he conduct surveys at Hall II for documentation of the recently purchased property. 2013 • Discovery of a major little brown bat(M. lucifugus) maternity colony. • Discovery of the probable presence of a colony of eastern pipistrelles (tricolor bats) (Periniyotis subflavus)which would be the first colony of this species known in Colorado. 2014- Follow up information on the major colony of little brown bats first discovered in 2013- Dr. Adams radio-tagged little brown myotis and tracked to its maternity colony, located in a roadside rock face along the South St. Vrain Road just west of Hall Ranch II. The colony consists of few hundred individuals. Continued radio tracking and sonar recordings from detectors indicated the pathway this colony used to arrive at Hall Ranch 2 for drinking at the pools located at the Aggregate Mine Site. Lactating females require immediate access to calcium rich drinking sources upon night time emergence from their maternity colonies. The ponds at the Aggregate Mind Site are serving this purpose for the hundreds of individuals. Drinking bats require smooth surfaced, still water with clear access for watering. o This large maternity colony drank from the `Pool V site in the Aggregate Mine Site. (See map below) o Water testing 2014-`Pool V had the least amounts of potentially harmful chemical compound load. 2014 Continued- Detected high numbers of Mexican free-tailed bats detected indicating that a colony of this species has taken up residence in the area.