restoration of the island ecosystems has made significant progress. An example of conservation progress has been the bald eagle, which was threatened due to DDT contamination, but whose populations are now recovering. With the help of scientists from the USC Wrigley Institute for Environmental Studies, the Catalina Island Fox has also recovered from a low of 100 individual foxes to over 1,500 foxes in 2018. Occasional discussion on the status of the islands has arisen because they (and the Farallon Islands) were not specifically mentioned in the Treaty of Guadalupe Hidalgo which ceded northern Mexico to the United States. Citing these perceived legal ambiguities, in at least two cases settlers created unrecognized Micronations there. A 1944 review by the Mexican government apparently concluded that it had no claim to them, and a 1978 maritime treaty with the U.S. formally closed the issue. In 1972, in "a bit of political theater", twenty-six Brown Berets sailed to Catalina Island on tourist boats, set up a small encampment near the town of Avalon, put up a Mexican flag and claimed the island on behalf of all Chicanos, citing the Treaty of Guadalupe Hidalgo. Twenty-four days later, sheriff's deputies took everyone back to the mainland. Military use The United States Navy controls San Nicolas Island and San Clemente Island, and has installations elsewhere in the chain. During World War II all of southern California's Channel Islands were put under military control, including the civilian-populated Santa Catalina where tourism was halted and established residents needed permits to travel to and from the mainland. San Miguel Island was used as a bombing range and Santa Barbara Island as an early warning outpost under the presumed threat of a Japanese attack on California. San Clemente Island was used to train the Navy's first amphibious force to prepare for Pacific combat against the Japanese in World War II. San Nicolas Island has been used since 1957 as a launch pad for research rockets. Santa Rosa Island was used in 1952 as a base for the USAF 669th AC&W Squadron and they operated two Distant Early Warning FPS-10 radars from the hilltops there. In 1955 another FPS-3 search radar was added, and in 1956, a GPS-3 search radar was installed. A new MPS-14 long-range height-finder radar was installed in 1958. The base was shut down in March 1963, when the 669th was moved to Vandenberg AFB near Lompoc, California.