St. Vrain State Park is about 50 feet from highway 25, a major north/south route in the area. You can hear the traffic on the highway 24/7. The only exception might be when they close the road in the winter.

For being as urban as it is, the park has a significant amount of wildlife. Part of this appears to be due to the abundance of small lakes in the park. We have not been able to get pictures of many of the birds, but we have seen Osprey, American Pelicans, Canada Geese, Little Blue Herons, Seagulls, Red-winged Blackbirds, and Robins. The Canada Geese are nesting in and along the ponds.

We have also seen some small mammals running around. The rabbits frequent the reeds on the shore near our campsite. The prairie dogs have a colony of 25 to 50 members near the entrance of the park. As you approach the colony, you can see them scurry to their burrows and hear them barking their warning cry. We tried sitting near the colony to see if some would come back out.

After about 15 minutes, this poor prairie dog was getting hoarse from hollering at us. We packed up and left before we ruined his singing career.