A fecal analysis survey was undertaken to quantify animal inputs of pathogenic and indicator microorganisms in the temperate watersheds of Sydney, Australia. The feces from a range of domestic animals and wildlife were analyzed for the indicator bacteria fecal coliforms and Clostridium perfringens spores, the pathogenic protozoa Cryptosporidium and Giardia, and the enteric viruses adenovirus, enterovirus, and reovirus. Pathogen and fecal indicator concentrations were generally higher in domestic animal feces than in wildlife feces. Future studies to quantify potential pathogen risks in drinking-water watersheds should thus focus on quantifying pathogen loads from domestic animals and livestock rather than wildlife.The current trend in minimizing pathogen health risks to water supplies is to use a risk management-based approach to ensure delivery of high-quality water. This approach utilizes multiple barriers within the water system, including effective control of contaminant inputs through watershed management. One potential source of these pathogens in drinkingwater watersheds is the feces of domestic and wildlife animal populations. Pathogens from animal feces may enter waterways by direct deposition or as a result of overland runoff containing fecal material deposited in the watershed. To construct a source material budget of pathogen inputs, it is necessary to estimate the potential impact of animal populations on surface water quality (15). Subsequent analysis can then be performed to estimate the proportion of the source material that will be inactivated through natural decay and environmental stressors, how much may be transported to the stream network, and the proportion that represents a risk of human infection.The initial requirement for the development of a source material budget is to estimate the concentration of potential pathogens in animal feces (shedding intensity). There is limited published information on the concentration and input load of potential waterborne pathogens and fecal indicator bacteria in wildlife (native and feral animal) populations (2,3,8,19). Yet it is these animals that often have the greatest access to the riparian zones and reservoir surrounds in watersheds, since, by definition, their movements are largely uncontrolled, making surface water protection difficult. By comparison, data for potential pathogen concentrations in the feces of domestic animals are more abundant, particularly for the enumeration and prevalence of the protozoan parasites Cryptosporidium and Giardia spp. (4-7, 18, 24, 25).This study was undertaken to provide a cross-sectional estimate of the intensity of shedding of pathogenic and indicator microorganisms in animal feces present in a large, semiprotected drinking-water watershed. The study quantified potentially pathogenic protozoa (Cryptosporidium and Giardia), enteric viruses (adenovirus, enterovirus, and reovirus), and indicator organisms (fecal coliforms and Clostridium perfringens spores) in fecal samples from watershed animals. The latter are t...

The effects of surfaces on the physiology of bacteria adhering to surfaces or immobilized within biofilms are receiving more interest. A study of the effects of hydrophobic and hydrophilic substrata on the colonization behavior of a marine bacterium, SW5, revealed major differences in the morphology of SW5 on these surfaces. Using epifluorescence, scanning confocal laser, and on-line visualization (time-lapse video) microscopy, the organisms at hydrophobic surfaces were characterized by the formation of tightly packed biofilms, consisting of single and paired cells, whereas those at hydrophilic surfaces exhibited sparse colonization and the formation of chains more than 100 microns long, anchored at the surface by the terminal (colonizing) cell. The results are discussed in terms of the possible factors inducing the observed morphological differences and the significance of these differences in terms of biofilm structure and plasmid transfer when SW5 is the recipient organism.

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