What are the things you can do in Costilla County? Fishing, fly fishing and boating provide recreation for anglers local and visiting. The reservoirs teem with the likes of walleye, pike, bass, several species of trout and other types of fish. For those more interested in nature watching, the reservoirs house a variety of wildlife. Deer, elk, antelope, coyotes, bears, bighorn sheep, mountain lions and Sandhill cranes are common sites in these areas. Large herds of 100 elk are not uncommon. Hiking, sledding down giant sand dunes, ATVing, skiing and so much more.