A PCR marker for detection in surface waters of faecal pollution derived from ducks

Detection of the faecal pollution contribution from wildfowl is an important adjunct in determining the sources of faecal pollution in waterways. This is particularly true, where human waste and other animal faecal sources have been eliminated as the pollution source. A polymerase chain reaction (PCR) marker was developed as a duck-specific marker of faecal pollution. The semi-nested primer system targeted an unknown bacterium (E2) isolated from mallard ducks. E2 had the closest 16S rRNA sequence similarity to members of the Desulfovibrio genus, which was further confirmed by phenotypic characterisation of the bacterium. Testing of the prevalence of E2 identified the marker in 76% of duck faecal samples (n=42), 20% of swan faecal samples (n=10) and 15% of Canada geese faecal samples (n=20). It was also identified in the faeces of two out of 15 domestic goats (13%). The marker was not detected in any samples derived from human faeces or effluent, dairy cows or sheep. It is proposed that this PCR marker would be useful in conjunction with faecal taxation indicators in the determination of pollution derived from duck faecal inputs in waterways.