Answer: I have not been able to uncover a documented case of an animal being poisoned from eating a bird killed from eating nandina berries.
However, Bob Sargent, Program Manager of the Nongame unit of Georgia’s Nongame Wildlife Conservation Section has advised me that he talked to a veterinarian familiar with nandina poisoning cases. This researcher indicated that secondary poisoning is theoretically possible, especially if an animal consumes a bird that has just died (e.g. its carcass is still warm) or, if the dead bird’s crop is packed with nandina berries and the scavenger eats the crop. The reason for this is that the cyanide rapidly dissipates when it is consumed.
The veterinarian went on to say that, if a cedar waxwing eats just a few nandina berries along with other fruits and berries, it will probably survive the experience.
The popular exotic shrub, nandina (Nandina domestica), has long been touted as is member of an elite group of plants that beautify our home landscapes while also serving as a source of food for birds and other wildlife. However, scientists working with University of Georgia School of Veterinary Medicine, Southeastern Cooperative Wildlife Disease Study (SCWDS) in Athens, Georgia report that nandina berries are poisonous to birds.
In a growing number bird die offs investigated by
SCWDS researchers, the birds they examined had succumbed to hydrogen cyanide poisoning. One such case involved dozens of cedar waxwings found in Thomasville, Georgia. When the researchers examined the victims, they discovered that the birds’ crops were full of nandina berries. It seems that chemicals found in the berries produce hydrogen cyanide. This potent poison can kill its victims in less than a hour.
Several recent nandina-linked bird deaths in Georgia are not unique. Nandina berries have also been found responsible for the demise of birds in other parts of the United States.
It should also be noted that hydrogen cyanide is also known to be toxic of cats, dogs and a number of other animals.
Those of us that have nandinas growing in our yards, should consider digging them up. If we don’t want go to that extreme, we can at least remove, bag and dispose of the berries. We should keep in mind, if we don’t eradicate the plants, there is a good chance that this highly invasive exotic pest will spread beyond our yards and become a more serious problem.