Wednesday, August 08, 2007

Traveling with friends 2007 - Day 3

June 27, 2007 - We headed west across Oregon via Hwy 26, and then connected to Hwy 97 and 197 up to the Dalles. One of the first bird sightings of the day was of this osprey nest atop an old pine tree snag. The nest was several feet wide and tall, covered with moss and lichens - obviously a well-used nesting site year-after-year. This is the first natural osprey nest I've ever seen and it was quite a treat.

Just a few miles down the road we came upon a wetland with the typical man-made nesting platforms. Somehow, this nest is just not as interesting as the one on top of the old tree snag. I'm glad the ospreys use these, though, because the population has been doing pretty well.

This is a view of the Strawberrry Mountains, and the wilderness area up there in the alpine zone. I wish we had the extra time to hike in there, but at this point in our trip we needed to make some good time in order to get to Portland and the AAW symposium.

You do get a nice view of the grassland biome typical of central Oregon highlands, though.

Gigi was interested in the Tragopogon infructescence. You don't see these in South Africa.

They look like huge dandelions in fruit, except they're ten times or more the size of the dandelions.

Each achene (fruit with seed) has a long plume-like structure that the wind picks up and carries for long distances. It's an excellent dispersal mechanism.

This is a species of Linaria, common name is toadflax. The long floral spur collects nectar, and the bees have to pry open the flower to collect it. In the process, they get covered in pollen and carry it from one plant to the other.

I grew up in Oregon and the pioneer and Oregon Trail history was just part of the background when I was a kid. It was fun to see some of the tourist sites that explain Oregon history, and this conestoga wagon sign board was a good reminder of that history. Hwy 26 travels along the old Oregon Trail. You can still see the wheel ruts in some sections of the preserved trail.

I wanted to show Dennis, Gigi, and John the exhibit where the dinosaur was being excavated from the hillside, which was one of the reasons I chose Hwy 26. Unfortunately, my memory isn't all that great and I was confusing Dinosaur National Monument with the John Day Fossil Beds - I was only off by about 80 million years or so. . . I did so much traveling through the western states 10-15 or so years ago when I was doing a lot of field work. My memories of what was where are kind of all jumbled together.

However, there were no disappointments from my friends since all of this back road territory was still very interesting to see.

At the first major overlook there were a lot of signs telling visitors all about the geology.

One of the most interesting things to know about this area is that the region was flooded with lava via major eruptions, the last of which ended about 4 million years ago. I had mentioned a bit about this in a previous post on the hotsprings of Idaho and Craters of the Moon National Park. A graphic such as in this map really brings it home, though. Some basalt deposits are 15,000 feet thick in the region covered by flows.

In between major eruptions, the area became a fertile grassland and savannah. This was the age of mammals during the Miocene. The fossils from this area of Oregon are dominated by the mammals endemic to the region.

The tops of the hills show the Rattlesnake formation - flows of Ash tuff (superheated and welded together), which occured 4 - 6 million years ago. The whole region is dominated by successive volcanic events going back about 50 million years - mud flows, lava flows, ash flows and the like. It looks so peaceful and calm now, but who knows what events will shake up the region in the future?

The John Day River has carved through much of the region and you can see a narrow gap through the hill in this image (look for where that sharp peak sits above the gorge). The native Americans etched and painted images in the gorge, which caused it to be named, "Picture Gorge" by the pioneers traveling through here.

Two geological formations to notice in this picture: The top layer is welded ash tuff cap called the Rattlesnake formation. Below that are the Mascall deposits - massive ash layers. Each layer of geological deposit is rich in the fossils of animals and plants that lived there before the volanic layers buried them. This kind of rapid burial makes for excellent fossil preservation, which is why this area is so well known for the fossil flora and fauna.

Dennis and Gigi learning all about the geology at the overlook. At first glance, this landscape seems kind of uninteresting. However, once you know the geological history, it becomes much more interesting and you start to play detective games - trying to figure out what layer has what fossils and what the region must have looked like millions of years ago.

Even as a kid driving back and forth to Idaho for college, I played these games while driving across Oregon. I was particularly intrigued by an ancient river track that was high up in the mountains - the uplift of the region changed the path of the river, but the deposits of gravel, silt, and sand were still there for one to see.

One of the other things that made an impression to me as a kid was the petrified wood that is so abundant in Oregon. My dad worked for a sand and gravel company and he brought a lot of this type of fossil home for us to see. This is a chunk of wood from a fossil tree that was buried about 40 or so million years ago by volcanic ash or a mudflow.

We stopped at the visitors center, and the first thing I noticed was that all the buildings were being used by birds for nesting areas. Cliff swallows had nests all along the overhangs of the roof.

Here's a Western Kingbird with a huge bug in its beak. It didn't seem too happy about where I was standing, and so it was giving me a thorough inspection.

I didn't pose much of a threat, so it carried on with its business.

Feeding three hungry chicks.

"What? Don't you have something better to do? Shoo! Go away!"

Ok, so we went inside where it was nice and cool and there were some interesting exhibits to see.

This explains a bit about the terrain and habitat from 40 million years ago.

Fossils from that era.

The visitors center is named after this researcher - one of the first to recognize the significance of the fossil beds here.

The first explorations came during the heyday of Natural Theology ala' Paley. During the 1600's to 1800's naturalists were to study nature to try to understand the nature of God. Reconciling the fossils with a creation ideology was not a particularly interesting or fruitful endeavor, but Condon made a huge effort to accommodate science and religion.

The visitor center has a wall of windows where you can observe the work being done to release the fossils from the rock.

They also have a lot of public outreach going on there - always good to see from a perspective of science education and scientific literacy.

Meanwhile, back outside, the birds continue to feed their young despite curious onlookers. John was trying to help me determine how many chicks were in the western kingbird nest.

We continued our travels westward and stopped in a valley at the edge of some cliffs. The raptors were very abundant there, taking advantage of the thermals. Here's one of the bald eagles we saw on this day.

Red tailed hawks were super abundant, too.

It took a bit of effort to identify these birds because the plumage pattern of the western populations are sufficiently different to what I've keyed in on for the eastern ones that I had to really look hard at the fieldmarks.

This photo is pretty good for that - the dark line on the leading edge of the wings is what I eventually started to look for.

Here are three using the same thermal.

We saw a lot of turkey vultures as well.

Another good look at a western kingbird.

I don't remember the name of this little town, but we stopped for lunch and the local flavor. These guys had a lot to say about nothing.

As we turned north and drove toward The Dalles, we came upon this huge wind farm. I didn't know Oregon was so far along in this energy utilization.

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