The five American navy sailing ships initially stationed in the Pacific had a force of 350-400 U.S. Marines and bluejacket U.S. Navy sailors on board available for deployment and were essentially the only significant United States military force on the Pacific coast in the early months of the Mexican–American War. The Marines were stationed aboard each warship to assist in close in ship to ship combat for either boarding or repelling boarders and could be detached for use on land. In addition there were some sailors on each ship that could be detached from each vessel for shore duty and still leave the ship functional though short handed. Naval gunnery officers typically handled the small cannons deployed as artillery with the sailors and marines.