Day 22-Hat Rock RV Park to Crow Butte Park-44.81 miles

We have wanted to camp at Crow Butte Park since the beginning of the trip because it is located on an island in the middle of the Columbia River. We called the night before to make a reservation and were told by the Washington Parks Department that Crow Butte didn't exist. Disappointed, we headed out anyway, figuring it might be necessary to go further if, in fact, the campground was closed. We passed through the town of Umatilla and stopped at the Visitor's Center there. The lady told us that the park DID exist, it was just under private management. She did mention that the park had a rattlesnake problem, though. We talked it over and decided to take our chances with the rattlesnakes. We got a phone book, found the number and made a reservation. We biked on to Crow Butte as the landscape became more desert-like, and the heat built steadily. Our campsite was beautiful. Out one door of the tent we could look out over the desert and out the other we could see the Columbia River. Speaking of the Columbia, we spent part of our afternoon skipping rocks on the river.
Later that evening, one of our kindly neighbors came over to our site bearing a bag of ice, since the water from the faucet was warm! What a treat! Ice cold water to drink. He even offered to cook us a steak, but we had already eaten and were ready for bed. We regretfully had to turn him down.

-clarkwheel

Student question: Rattlesnakes have two methods of detecting prey. One is visually seeing their prey. The other is to locate prey with special sensory organs that can detect what?