meant to be as much of a research organization, but a "development and administrative service." The DWS dealt with policy and methods in the conservation and management of wildlife resources. "Few people in the 1940s saw wildlife from a holistic point of view. Like trees, birds, mammals, and fish were generally viewed a resources to be responsibly managed for the purpose of generating long-terms economic returns." Wildlife was a national asset. By 1950 the DWS was known as the Canadian Wildlife Service (CWS). Harrison Lewis was the first head of the new service, remaining in that post until his retirement in 1952. When the CWS was founded, important research on wildlife had been undertaken through the National Museum of Canada. After 1947, CWS scientists and technicians earned recognition for research including work on migratory birds, particularly waterfowl and sea birds, in addition to barren-ground caribou and polar bears in the northern territories. Although Last Mountain Lake Bird Sanctuary in Saskatchewan was first created in 1887, many Migratory Bird Sanctuaries were established in the 1950s and 60s, and National Wildlife Areas in the 1960s and 70s. In 1973 the Canada Wildlife Act was passed, giving the federal government clear authority to undertake wildlife research, acquire lands for wildlife conservation, and deliver interpretation activities. Significant growth of the organization occurred during this period, and CWS began providing broader wildlife research and management services to National Parks. In the 1960s, 1970s and into the early 1980s, Canadian Wildlife Service produced Hinterland Who's Who, a successful series of 60-second educational public-service television clips about Canada's native wildlife. The first four black-and-white vignettes - on the beaver, the moose, the gannet, and the loon - were produced through a collaboration with the National Film Board and the CWS. The vignettes resulted in millions of pamphlets about wildlife being mailed in response to viewers' requests to CWS. Individual Canadian Wildlife Service scientists and biologists became renowned for their work in conservation. Ernie Kuyt became well known for his pioneering work on the recovery of Whooping Cranes in Wood Buffalo National Park. Ian Stirling had a long career monitoring polar bear populations and discovering the effect of climate change on arctic ice and polar bear survival. Environmental contaminants and toxicological effects on wildlife became a significant focus of research programs in the 1960s and 70s. Tony Keith, director of the National Wildlife Research Centre from 1976 to