Sentence:  As well as being worth millions of dollars to the Texan agriculture industry, these mammals are worth millions of dollars to the state's tourism industry. Texas is home to the world's largest known <WSD>bat</WSD> colony (in Comal County), and the world's largest urban <WSD>bat</WSD> colony (in Austin). <WSD>Bat</WSD> watching is a common activity, with the Texas Parks and Wildlife Department offering more <WSD>bat</WSD>-viewing sites than anywhere else in the US. 
Meaning of the word marked with <WSD> tags:  Any of the small, nocturnal, flying mammals of the order Chiroptera, which navigate by means of echolocation.