Swallows and Martins are found in the Hirundinidae family. They are small, slender birds with long wings and large mouths and spend most of their time in the air feeding on insects. Although they are different in appearance and color, most have dark upperparts and light underparts. Some have forked tails and some nest in large colonies. They are very adept and fast flyers, agile and fluid in their motions. You might find them perching in long rows on wires and trees.