For fishermen like Joey Marabe in the Philippine province of Zambales, the geopolitical contest playing out in the South China Sea can be measured in dwindling catches and shrinking incomes, as the presence of Chinese vessels around a contested shoal increasingly limits where they can work.“It’s a huge drop. Before, a lot of us who could go out to Scarborough Shoal used to bring home around 15,000 pesos (US$238) a week, a comfortable amount for our families,” said Marabe, a resident of Masinloc...