Between October 2011 and September 2012, 463 people died in the desert after slipping across the U.S.-Mexico border – the most since 2005, when about three times as many entered the country illegally. Today, migrants are eight times more likely to die than a decade ago, according to the National Foundation for American Policy. Most used to cross near San Diego, or other border cities. But in the late 1990s, when the feds stepped up enforcement there, migrants began more dangerous treks across Arizona's remote Sonoran Desert, where heat exhaustion killed hundreds. Now, the pattern is shifting again. More migrants are Central American and take freight trains up Mexico's Gulf Coast, entering through south Texas. By the time they arrive, many have traveled for over a month under rugged conditions and are already weakened when they reach the desert. Increased legal avenues into the U.S. for low-skilled immigrants, such as temporary work visas, might ease the situation, but others argue tougher enforcement is the way to reduce border deaths.