Analysis of nectar replacement products and a case of iron toxicosis in hummingbirds

Twenty-five of 26 hummingbirds (Trochilidae) from 7 species previously maintained in an aviary on a commercial nectar substitute for 13 years, died over 3-month period. Gross necropsy was inconclusive; however, staining of liver and intestinal tissue showed high levels of Fe deposition. Analysis of separate bags (n=9) of the nectar product, with identical lot numbers, showed variation in Fe content...