Last year, there were 47 epizootic events reported or investigated by the National Wildlife Health Center (NWHC) in the Midwest. This included about 27,000 dead birds.
Of the Midwestern states, most of the mortality occurred in Minnesota and was caused by trematodiasis. Deaths by the disease constituted the largest mortality category, which is two and a half times larger than last year. In the case of the waterfowl, trematodiasis was caused by eating grain that had spoiled due to long periods off the stem and on the ground or in water. Most of the birds affected were American coots and lesser scaup, and were located in the Upper Mississippi River National Wildlife Refuge and Lake Winnibigoshish.
Fungal pneumonia, or aspergillosis, which is an infection or allergic response due to the Aspergillus fungus, was the second largest mortality rate. The disease killed an estimated 7,000 mallards.
In other news relating to bird diseases, avian botulism (type C), which is a paralytic disease caused by ingestion of a toxin produced by the bacteria Clostridium botulinum, continues to be a significant factor in the death of birds. There were 11 events reported where about 2,200 birds were killed.
For more updates on diseases and mortalities involving wildlife, visit the NWHC website: www.nwhc.usgs.gov.