In fact, bacterial contamination in ponds and reservoirs is far more often attributable to problems with human sanitation than to problems arising from any wild animals. The HSUS has yet to find any study that demonstrates a public health threat posed by geese. Good science and monitoring have shown that geese do not contribute in any significant way to elevated levels of potentially harmful bacterial contamination of water. On the contrary, studies have shown that geese often are exposed to pre-existing bacterial contamination in ponds already polluted by surface runoff. Any modest contribution from geese is easily mitigated by nonlethal methods of control, such as reducing the attractiveness of municipal water supply sites.
Some people suggest that goose populations are damaging ecosystems.
This claim is utterly without basis. No study of the role of geese in urban or suburban ecosystems has ever been conducted. The principal valid complaint against Canada geese is that they defecate on lawns, golf courses, corporate grounds, and playing fields. This complaint is used to justify rounding up and destroying thousands of them annually. The difference is that the 1996 programs are designed to capture geese for slaughter.