Monday, June 14, 2010

New Players

Our fourth week of the Flammulated Owl Survey season brought a new twist - new partners in the field. This is the 5th field report of my work on surveying for Flammulated Owls in and around the Sawtooth National Forest in Idaho. You can read all the previous posts in The Life of a Field Biologist, Meeting the Locals, Back in the Wilds, and Drizzle, Rain and Mud.

To help get more coverage before the end of the Flammulated Owl breeding season, this week we were supplemented with a BLM raptor crew. Therefore Jack and I split up, each to take on and train a new BLM crew member. My partner, Heidi (different Heidi than I usually work with), is from New York. She was a quick study in the area of owl surveys having worked the past few months looking for raptor nests in the canyons across southern Idaho. We got along great and she was strong in the mountains.

The first night up at the headwaters of the south fork of the Boise River was a total bust - no owls, no nightjars. Null surveys can be just as important as having many detections. They inform in which habitats the owls are not present. These forests were dominated by Lodgepole Pine and Sub-alpine Fir. The Aspen present was reasonably young. Not the best habitat for cavity nesting owls. The highlight of the night was watching a Dusky Grouse display for his date. This was a first for me to observe a male Dusky in action.

The location for day 2 didn't work out due to very high water. Therefore we transferred to Featherville to repeat one of our top 5 sites. The top 5 priority sites we will visit a total of 3 times each. This will help determine how detectability changes through the season. We ended up detecting 5 Flammulated Owls and 1 Barred Owl. On the way we observed a lesson in poor parking form. This is not a good place to leave a truck. Apparently everyone made it out ok, but that looks like a nasty swim.

South Fork Boise River.

For day 3 it was back to the headwaters of the Boise River for a road survey. This would be another null evening. The only thing we detected were Methodists at the Methodist camp out cruising the woods at midnight. Hmm. That was unexpected. We played the owl call for them but they did not respond.

Day 4 was on to BLM sites. We couldn't access our primary site, so it was over to a backup site. As it ended up the Idaho Bird Observatory songbird crew surveyed that site the same morning. They provided us critical information that made our life easier. Some of the survey points we had targeted were near streams. They told us which ones were too loud for detections. This save us hiking a lot of vertical terrain. Before heading out to our points a massive hail storm hit, piling up hail on the ground. The storm would clear just before our time to head out. As we waited in the truck a buck mule deer walked up and licked mud off my drivers door. Apparently there was salt in the mud. Fascinating. It was finally time to go. The storm had passed but the wind remained. We would not detect any owls, likely the result of wind noise interference. I'm not sure we will have the opportunity to repeat this site under more optimal conditions. After a short weekend, its back up into the wilds with my buddy Jack.

Sunday, June 06, 2010

Drizzle, Rain, and Mud

Our third week of the Flammulated Owl Survey season was dominated by rain and its aftermath, mud. This was not to interfere with our adventures in hiking through the wilds at night, but simply to enhance it in new and interesting ways. This is the 4th field report of my work on surveying for Flammulated Owls in and around the Sawtooth National Forest in Idaho. You can read all the previous posts in The Life of a Field Biologist, Meeting the Locals, and Back in the Wilds.

Upon receiving the maps for our third week out, we were somewhat relieved. This looked to be a much easier week. If that is so, why am I so damn tired? The bottom line is that 9 miles of hiking and 2000 ft vertical a night, while easier than 9 miles and 3000 ft vertical, is still a lot of work.

Our destination for the first three days of the week was the Sublett Mountains in South-Central Idaho. This is a remote extension of the Sawtooth National Forest. Upon arriving on Memorial Day we saw a number of campers packing up to go home. These would be the last people we would see for two days. On our last day there a new camper arrived to spoil our silence.

The forests are much different there. There is a great deal more mature aspens trees than further north where we have been working, and many of the slopes have juniper as well. The bird diversity, which we also informally document was quite high - approximately 40 species in each survey area. We specifically take note of the woodpecker species as they may be a predictor species for small owl occupancy. They were also abundant in our survey areas. A friend of mine is studying this relationship between owls and woodpeckers as part of his masters thesis. I spent some time with him in the field last year surveying for owls and woodpeckers. Woodpeckers excavate the nest holes used by Flammulated and other small Owls.

The first night out surveying resulted in another 4 owl species night, this time with our first Northern Pygmy Owl! These were joined by Flammulated, Northern Saw-whet and Great Horned Owls. Remarkable was the large number of Great Horned Owls in the area. The highlight of the evening was a probable Flammulated Owl flying into the tree next to where we were surveying. Our protocol involves a 2 minute silent listening period followed by 4 segments of 30 second playback (broadcast of a Flammulated call) followed by 90 second listening. There was a nearby Flammulated owl we detected during the silent listening period. Once we played the playback call, the owl went quiet. We observed an owl working its way from that direction, closer and closer, until it perched in the tree next to us. We could not conclusively identify it in the dark, but based on its behavior relative to our calls, it was most likely the first look I have had at a wild Flammulated Owl! The question is whether he/she came as a friend or a foe? Most likely a foe.

On day two we set up our road survey and completed the vegetation analysis. We also hiked our second set of remote survey locations to complete the vegetation analysis for that as well. Since the weather was highly questionable, we were preparing to hike if good weather or trying the road survey if it was poor weather. At the time, the weather was looking bad. Interestingly, for the second time in two weeks there was a moose on our survey point. It wandered off. As we approached again we found a second moose! We decided to skip that point and come back to it. By mid-afternoon, as we were finishing our hiking veg analysis, the sky opened up and it hammered us with rain. We discovered the road we were on to be impassable when wet. Our only chance was to head down valley away from our camp and loop back around on better roads. The road down canyon wasn't much better, but at least it was downhill. Momentum was the key. If we could keep the vehicle going fast enough, we just might slide through the nasty spots. After some very close calls- truck swallowing ditches and a near intimate relationship with a tree - we returned to more rocky and more stable roads. It took us another 2 hours to work our way around the mountains and back to camp. We ended up choosing the road survey, but still hiked half the route to cover the muddy sections. So much for the rest day we have grown accustomed to. We did however still accomplish our work objectives. It was a great owl night with - 12 Flammulated owls distributed across 9 of our 12 locations. 4 Great Horned Owls and 2 Northern Saw-whet Owls rounded out our results. At one survey point we had one of each of the three species.

On day 3 it rained. It rained a lot! All afternoon it rained. We expected the night to be a bust. We had already completed the vegetation analysis the previous day, so we could make a decision at the last minute. At 8pm the clouds cleared and we quickly packed up and hit the road. We started hiking at 9:10pm and reached the first point right on time to begin the survey at 9:30pm. Two Northern Pygmy Owls and a Flammulated Owl right from the start. We would continue our streak with multiple owls at each survey point until the rains hit while at point 6. We tossed the final two points and headed for the truck. We finished the night with an astounding 19 Flammulated Owls, 2 Northern Pygmy Owls, and a Northern Saw-whet Owl. At one point there were 6 owls. It was crazy trying to to sort them out.

It continued to rain off and on as we moved to the South Hills South of Twin Falls Idaho. We arrive to discover the road to our points gated and locked. We are able to get within 2km of the first point so it worked out ok. We headed out at 5pm to complete the vegetation analysis under heavy clouds, dark skies, and very muddy terrain. The forest habitat consisted of largely younger aspen with lodgepole pine. We expected a low count with the exception of a few points. We ended up doing well on those points and not on others. The end result was 4 Flammulated, 1 Northern Saw-whet, and 1 Great Horned Owl. It drizzled on us all evening, but didn't rain hard enough for us to abandon. The wet terrain resulted in many falls and slides, but it worked out in the end. We were somewhat happy to finish this wet and muddy week, with a promise of better weather next week.

The Fish and Game truck continues to solicit comments about wolves, even in front of my house. In our conversations north of the snake river the topic of wolves has arisen in 100% of the discussions. Not so in the South Hills. While there is good habitat, there hasn't been any wolves there since they were exterminated by humans some 80 years ago. As Aldo Leopold so eloquently reminded us in "Thinking Like a Mountain", what is the mountain's view of this. Probably not a positive reaction. Of course the mountain is probably not too happy with our other transformations either - 4 wheeler trails everywhere, beer cans littered about, etc.