Please rewrite the following text to have better cohesiveness
The refuge, comprising 316 acres (1.28 km) of salt marsh and coastal uplands surrounded by urban development, is a critically important area for wildlife. Over 90 percent of the historic wetlands of San Diego Bay have been filled in.
The refuge, comprising 316 acres (1.28 km) of salt marsh and coastal uplands surrounded by urban development, is a critically important area for wildlife because over 90 percent of the historic wetlands of San Diego Bay have been filled in.