In a fragile ecosystem, how do you conserve limited resources for future generations? That's the question that the small Pacific island nation of Palau is grappling with as it tries to combat illegal fishing. The country's rich marine ecosystem is now at risk, as boats from Southeast Asia venture farther into its crystalline waters in search of tuna and other prized fish. Watch part one of our Great Big Film, "Sea Change," by our friends at Vacationland. Watch part two here.