Phoenix Metro Ducks
I was surprised to find out how many species of ducks winter in the Phoenix area, and how easy they can be to photograph here. Quite unlike my experience of the same species back in New Jersey, where getting close enough for good image size was always difficult. Here in AZ the ducks winter in artificial ponds at local parks or corporate complexes where there is lots of foot traffic from joggers and pets, so the ducks get used to people. At many of these places, the ducks get used to handouts from family groups.
ASU Research Park
My current favorite location for this is a series of large ponds at the Arizona State University Research Park in Tempe, a few miles east of I-10. The Research Park is located between Elliott on the north and Warner on the south, and between McClintock on the west and the Price Loop 101 on the east. Entry is from either Elliott or Warner. Parking is a problem, so pay attention to signage.
I sit along the water's edge at the southernmost point, or on the south side of the pond on the west of the main drive through the complex. Kneepads are useful and allow some ability to move about while still staying low behind a tripod. Good subjects here are Ring-necked Duck, Lesser Scaup, American Wigeon, and Green Heron.
Papago Park is adjacent to the Phoenix Zoo, on Galvin Parkway between the zoo and the Desert Botanical Gardens. Turn left from the zoo entrance road and visit the series of artifical ponds. Ducks that winter here can be some of the easiest to photogragh in the country. Also watch for tolerant Green Herons. Don't overlook other "junk" birds such as Rock Pigeon and Great-tailed Grackle.
McKellips Park, on the north side of McKellips Road just west of McClintock/Hayden Road, has hosted a drake Euragion Wigeon for at least the past five winters. It hangs out with the flock of American Wigeons and American Coots, and comes for handouts.
Scottsdale Greenbelt Ponds
The Scottsdale Greenbelt (the drainage between Scottsdale Road and Hayden Road north of McKellips) has many other local parks and ponds where ducks, coots, herons, and other waterfowl are used to people and can be approached closely.
A large shallow "lake" south of Baseline east of the I-10 in Tempe. Ducks can be anywhere here but are easiest to photograph at the north end by the paddle boats or at the south end.