Technical Abstract: Since 2002, H5N1 high pathogenicity avian influenza (HPAI) viruses have been associated with natural, lethal infections in wild aquatic birds which have been reproduced experimentally. Some aquatic bird species have been suggested as potential transporters of H5N1 HPAI virus via migration. However, a similar wild bird potential infectivity and spread for the 2002 Chilean H7N3 low pathogenicity avian influenza (LPAI) and HPAI viruses is unknown, but the closest viral relative was an H7N3 LPAI virus isolated from a migratory duck, a cinnamon teal, in Bolivia in 2001. Two different wild duck species common in Chile and neighboring countries, chiloe wigeon (Anas sibilatrix) and cinnamon teal (Anas cyanoptera), were intranasally inoculated with 10*6 mean infective doses (EID50) of LPAI virus (A/chicken/Chile/176822/02) or HPAI virus (A/chicken/Chile/184240-1/02), in order to study the infectivity, transmissibility and pathobiology of these viruses. None of the virus inoculated ducks had clinical signs or died, but most seroconverted by 14 days, indicating a productive virus infection. Both LPAI and HPAI viruses were isolated from oral swabs from two out of eight chiloe wigeons and from oral and/or cloacal swabs from all of the cinnamon teals at day 2 post inoculation. The virus was efficiently transmitted to cinnamon teal contacts but not to chiloe wigeon contacts. This study demonstrates that the cinnamon teal was susceptible to infection with both Chilean H7N3 LPAI and HPAI viruses, and potentially could have been involved as a primordial reservoir and transport host.