Is it a health risk if geese cause elevated coliform levels in lakes and ponds?
No. Coliform bacteria are found in the intestinal tracts of all warm-blooded creatures (mammals and birds). Coliforms themselves are not disease-causing; they are just easily measured “indicator organisms” used to determine whether or not fecal matter is present in the water. Coliform tests are not capable of indicating from which species the coliforms originate, nor whether a true health risk exists. While geese can raise coliform levels, this is of no consequence, because it is known that goose fecal matter does not contain bacteria of concern to human health. While Canada geese are often blamed for posing a health risk, detailed studies invariably show that when a health threat really does exist, it has nothing to do with geese. Instead, the culprit is often found to be human waste leaking from faulty sewage or septic systems, and/or runoff from animal farms. For more information, see our section on public health.
