Controlling Parasites

There are two suggested treatments to control blowflies and mites. They are nest replacement and fresh water diatomaceous earth (D.E.). Diatomaceous earth is the only substance The Nature Society currently recommends for parasite control. Several others have been proven effective, but none have had extensive tests on the negative affects on birds. Diatomaceous earth, unlike other pesticides, kills by cutting the exoskeleton of the bugs, but the cutting surfaces are so microscopic it can be eaten with no ill effects. Be sure that you are using the fresh water type. Do NOT use the salt water type (sold at swimming pool supply shops) which is ineffective.

There should be two treatments, one before the birds arrive and a second as a part of nest replacement about ten days after the eggs hatch. (The martins won't mind the disturbance.) The second treatment is most important. Fresh water diatomaceous earth should be sprinkled generously underneath the sub-floors after cleaning out your martin house in the Spring and before the martins build a nest. If your house doesn't have sub-floors, then you must wait until the nests have been completed. Do not apply the D.E. directly on the young martins. Do not spray the D.E. into the nest area which might cause the nestlings to breath it.

Sevin, sulfur, and other pesticide products kill parasites by poison - which could be harmful to martins - particularly babies that are constantly exposed. Using pesticides on wild birds or their nests is illegal. D.E. is not a pesticide and is an effective replacement for the illegal sevin.