But, from these three colors, you can mix all colors found in the spectrum. Selecting Three Primaries. Probably the best way to choose primary colors is to browse through various art instruction books until you find an artist that sees, and interprets, color in the same way as you do. Deciding on which three primary watercolors to begin with can seem quite daunting, especially if you are new to watercolor.
144 Field Manual of Wildlife Diseases: Birds Figure 16.4 During the 1973 outbreakof duck plague at Lake Andes NationalWildlife Refuge in South Dakota, morethan 40,000 mallards died. Photo by Milton Friend from adjacent Flanders Bay, apparently as a result of diseasetransmission from white Pekin ducks.ittle is known about the response of wild water-fowl to strain differences.Duck plague outbreaks are thought to be caused whenbirds that carry the virus shed it through fecal or oral dis-charge, thus releasing the virus into food and water withwhich susceptible birds may have contact.
Although birds can spread bacteria to people, illness caused by touching or owning birds is rare. To best protect yourself from getting sick, thoroughly wash your hands with running water and soap after contact with birds or their droppings. Different types of birds can carry different diseases. For example, baby chicks and ducklings often carry the bacterium Salmonella. This bacteria causes salmonellosis (sal-MOhn-el-OH-sis) in humans. Parakeets and parrots can carry the bacterium Chlamydia psittaci (kluh-MID-ee-ah si-TACH-ee). This bacteria causes the disease psittacosis (sit-a-koh-sis).