Contribution of Bridge Dwelling Birds to Bacterial Water Quality Impairments

Approximately 50,000 bridges exist in Texas and some can be occupied by large nesting colonies of Cliff Swallows. Significant amounts of feces from these colonies can contaminate water resources either directly or as runoff from shore line following precipitation. The project will quantitatively determine bacterial loads (all bacteria, and Escherichia coli as indicator for fecal contamination) up- and downstream of bridges with Cliff Swallows colonies during dry weather and runoff conditions during two years. Sampling will coincide with periods when birds are not present, arriving, nestlings having hatched, and nestlings leaving, respectively, and thus represent times with no, little, medium and high release of feces from colonies in the environment. Additionally, source-tracking analyses that characterize E.coli strains up-and down-stream as well as in feces and quantify signature bacteria only present in bird feces will allow us to discern if bird feces are a contamination source. These methods will also allow feces load and microbe quantification in the water/soil samples. Microbial data will be contrasted with bird feces input estimates derived from nesting phenology and feces accumulation quantification. These variables will be analyzed to develop mathematical functions that describe their relationships.


  • English


  • Status: Completed
  • Contract Numbers:


  • Sponsor Organizations:

    Texas Department of Transportation

    125 E. 11th Street
    Austin, TX  United States  78701-2483
  • Performing Organizations:

    Texas State University, San Marcos

    JCK Building, Suite 489
    San Marcos, TX  United States 
  • Principal Investigators:

    Castro-Arellano, Ivan

  • Start Date: 20120912
  • Expected Completion Date: 0
  • Actual Completion Date: 20141130
  • Source Data: RiP Project 33844

Subject/Index Terms

Filing Info

  • Accession Number: 01568883
  • Record Type: Research project
  • Source Agency: Texas Department of Transportation
  • Contract Numbers: 0-6764
  • Files: RIP, STATEDOT
  • Created Date: Jun 30 2015 1:01AM