DULUTH, MN (KDAL) - According to the American Great Lakes Ports Association, ports throughout the Great Lakes saw increased tonnage in several categories during the month of June over May numbers. Director of Trade and Development, Rebecca Spruill, says ports are making up ground for the slow start to the season caused by heavy ice in April. The Duluth Seaway Port Authority Director, Vanta Coda says industry spirits were lifted by strong gains in cargo movements last month. June coal and iron ore tonnages were up by 16 and 7 percent respectively over May in the Twin Ports and both are running ahead of a year ago. He says total tonnage for the port is still off by 17 percent from last year at this time.