Wednesday, January 21, 2009

Gemini and Maria: "flew the coop?"

Right: Carl searching for Gemini near Tom's Run (Photo: Carl Leinbach)
Below: Lexi barely visible in a pitch pine

Yesterday, I went out tracking with volunteer Carl Leinbach to find Lexi's roost location. Carl and his wife, Pat, live nearby, and have been faithful volunteers for the entire season.

Mainly, they joined us for night-tracking, running around the woods and helping us chase down owls. It was great to have their company and help, and I will greatly miss working with them!

This was the second time Carl joined me on a roost check. A few months back, we tracked Quasi to a pitch pine, and documented it as her second use of the same tree. Lexi was again roosting towards the Buck Ridge, so we trekked up the steep slope that we have hiked more times than we can count in the last four months. We were having a few receiver problems, and ended up switching between 2 receivers to locate the owl (we think that the cold temperatures were interferring with the transmitter on the owl, the receivers, or both).

To get above the owl, we hiked higher than we needed to; it is easier to locate an owl starting out from a higher elevation than the owl to avoid the signal bouncing off the walls of a steep hollow, and being inhibited by the "shelves" that make up the slope. As we approached the area where we figured the owl should be, based on our readings from farther away, the signal faded away, as did the "bars" on the receiver (the signal from the owl's transmitter comes in as a "pulse" through the receiver, and this pulse can be monitored by sound, or visually through bars that continually fluctuate based on signal strength).

We were about to give up, when we both decided to start searching a nearby pitch pine. I was extremely doubtful that we would find her, but sure enough, we saw her little round body shining in the sun almost 60 feet up in a pitch pine. Thanks again to Carl for helping me hunt her down!

Next, we set out to track Gemini, who has taken up residence for over a month near Pine Grove Furnace State Park. There were no "beeps" to be heard anywhere near her usual haunts by Tom's Run. I last noted she was present on the 18th, and it is likely she left the area in anticipation of the few inches of snow that fell on the 19th. Maria also seems to be gone, and has not been located in her typical area since the 13th. The owls may have found a nearby hollow to roost in, or may have moved on further south, continuing their migrations. We will spend the next few days trying to relocate them.

Lexi's unusual roosting habits

Above: Lexi roosting on a dead branch (Photo: George Gress)

Left: A typical chestnut oak/pitch pine dominant roost location (Photo: George Gress)

On January 19th, I was joined by volunteer George Gress to track down Lexi. We found her near her usual roost locations, but this time closer to the bottom of the slope of the Buck Ridge. We found a very fresh pellet (at 10:30 am in the morning) underneath the pitch pine that Lexi was roosting in. Typically, saw-whets will find a clump of pine cones or needles on a dense branch to roost in, but today Lexi was completely exposed on a dead branch about 2 feet from the main trunk of the tree (see above pictures). Usually, it takes a few minutes of searching in a tree that you detect an owl in to get a visual, but as we were passing by her tree, George looked up and said "There she is!" Thanks to George for helping me find her and sharing his great photos!

Monday, January 19, 2009

Snowy night

This past weekend we had the worst cold to hit the mountains of central Pennsylvania since 1994 -- it was -8 at our house in Schuylkill County, and only marginally warmer at our South Mountain study site.

It appears that Maria may have left, at least the immediate King's Gap State Park area; ice and snow on the unmaintained state forest roads have made it hard to check whether she's simply moved to a new hollow. Lexi and Gemini remain, though, and Saturday afternoon - when the temp had clawed back above zero -- Anna Fasoli and King's Gap banding volunteers Jane and Maeve Charlesworth tracked down Lexi, high on Buck Ridge.

Last night Anna, new volunteer Lisa Rubin and I met at King's Gap to track Lexi, with snow squalls leaving a fresh coat. Fortunately, the temperature was nearly 30 degrees warmer than it had been the previous morning; in fact, the combination of dead calm and temps in the upper 20s made it one of the most comfortable tracking nights we've had in months - though I am a little nostalgic for swatting mosquitoes back in early October.

We sure got our exercise. What we've tended to see is that the owls leave their roost at dusk, move actively (sometimes covering long distances, as Lexi did last week), but after an hour or two they tend to settle in to one spot, sometimes not moving again for hours. We suspect they're flying from spot to spot until they locate an area with rodent activity, and once they make a kill, they'll plunk down to eat and digest. Because saw-whets usually eat one or two mice a night, we suspect they go through another period of active hunting sometime in the predawn hours, and we'll be looking at that next season, when we begin doing all-night monitoring (in the balmier nights of October and early November, not in subzero January weather).

Last night, though, Lexi didn't settle down. She stayed along the top of Buck Ridge, moving frequently enough that her signal kept fading in an out, and for most of the next six hours we chased her (slowly, carefully, quietly) around the mountain. We'd get into a good position, Anna and Lisa in one place and me several hundred meters away so we had converging angles with our receivers - and the owl would move. And again. And again.

At one point, I moved in several hundred meters with no headlamp, trying not to slip too much on the ice- and snow-covered rocks, when the owl apparently flew in and landed almost on top of me. She did the same thing and hour later, after we'd made an enormous loop and wound up halfway down the mountain near where we started.

It wasn't until 10:30 p.m. that Lexi's signal finally localized near the firebreak in King's Gap Hollow. Whether she 'd just felt the need to stretch, or was having trouble finding prey, she must have found something good. When we left her after 11 p.m. she hadn't budged in more than half an hour, and was presumably enjoying some warm mouse meat.

Wednesday, January 14, 2009

Wandering wings

Lexi, with a bag lunch (©Anna Fasoli)

What I love about this project is the way the owls keep surprising us -- even if it is occasionally inconvenient.

On Monday the 12th, Aura Stauffer checked on our three tagged owls and found them all pretty much where we'd expected them to be, with Lexi and Maria roosting in the upper reaches of King's Gap Hollow. So that night Anna Fasoli, Drew Weber, Jamie Flickinger and I met to track them, hiking half a mile up to the icy ridgeline to get into good position.

Only owls had other ideas. Maria quickly moved south through the gap and into Cold Springs Hollow, while Lexi zoomed off to the north and west. We decided to chase her, hoofing it back down the mountain, figuring Lexi had shifted to Irishtown Gap Hollow, the next one to the west.

Only she hadn't; there was no sign of her signal. Drew finally located her in about the last place I'd have expected - a small patch of riparian woodland along Yellow Breeches Creek in the valley below South Mountain, a 2.5-mile flight from her roost.

We spent the next five hours monitoring her minor movements within the woodlot, all of us speculating whether the heavy ice on the ridgetop had forced her down, and wondering if she'd remain in the valley to roost the next day.

She didn't. Anna relocated Lexi yesterday, even farther up the side of Buck Ridge than usual, in a dense laurel patch Anna had to crawl into on all fours. This is the first time we've documented a nearly six-mile commute between roosting and feeding sites, a remarkable distance for a small owl.

What's more, Lexi was perched on the ground, holding half a deer mouse leftover from her nighttime hunting, with lots of whitewash on the snow around her. All saw-whets are easy to approach in daylight, but Lexi is unusually tame around us. To get these amazing pictures once she'd finished collecting habitat data, Anna held the camera just an inch or two from Lexi's face (if you look, you'll see Anna's reflection in the owl's eyes).

Concerned Lexi might become fox food if she stayed where she was, Anna poked her gently to make her fly. At first, Lexi simply landed on Anna's backpack, then finally flew a few yards to land up in the laurel.

(©Anna Fasoli)

Friday, January 9, 2009

Icy wonderland

The icy wonderland that is South Mountain...with snow on the way. (©Aura Stauffer)

Both Anna and Aura were out tracking yesterday, and between them they found all three of our telemetry owls.

Anna found Gemini in a tall white pine in her accustomed area along Tom's Run in Michaux State Forest, back near a roost she used Jan. 3. It's a stand of pines and hemlocks northeast of a small cabin that sits near the middle of her winter territory. Everything was still covered in ice, with the wind knocking some of it down; Anna said that Gemini (I keep calling it "she" out of habit, even though it's a sex-unknown bird) was fluffed up in the cold.

A little keepsake from Lexi - a fresh (and frozen) pellet, one of many we've collected and will analyze to see what the owls have been eating. (©Aura Stauffer)

Aura tracked down both Maria and Lexi, who are staying on King's Gap State Park property in upper King's Gap Hollow, as usual. Lexi was perched in a small pitch pine in the firebreak, and Aura was able to collect a pellet from below her roost, while Maria was .3 mile away, not far from the firebreak and back in the same tree she used Jan. 4, and which Quasi had used almost exactly two months earlier.

As you can see from Aura's photos, South Mountain is a real icy wonderland right now, and it may become even more of a challenge to get around after Saturday, with the prediction for 4-6 inches of snow starting tonight.
(©Aura Stauffer)

Thursday, January 8, 2009

Gemini, Lexi, and Maria still in area!

Can you spot Lexi?

Ice blankets Michaux State Forest

Another ice storm blanketed Michaux State Forest and King's Gap State Park two nights ago. Usually following an ice storm in the area, the temperatures rise and all of the ice melts within a day or so, creating a soggy mess. With temperatures staying low, however, the ice has stuck around, creating an icy masterpiece in the woods. I set out early this morning to find Gemini, as small chunks of ice were falling from the trees as the sun warmed everything up. I soon found her 35 meters away from a tree I had found her in on their third of January, in a large white pine stand. Today, she was about 52 feet up in a white pine, and easy to spot, as she was quite puffed up to stay warm.
On the 4th of January, I was able to track all three owls. I found Gemini about 40m away from a tree she had used late last month, in a white pine stand that she had been favoring. I then found Maria in a pitch pine that Quasi had used on November 9th. This is the second time Maria has used the same tree as another of our owls. To the human eye, the tree looks quite similar to the hundreds of other pitch pines in the forest, but there is something quite attractive to it from a saw-whet's perspective. I then found Lexi in a very thick mountain laurel patch, only a few feet off the ground. She was intent on watching me collect data, but never seemed overly jumpy or frightened, as owls sometimes do when found at this height. I was able to snap a few photos. The first photo above demonstrates just how well a saw-whet can be camouflaged in such a thick patch of mountain laurel.

Thursday, January 1, 2009

Hello, neighbor

After a holiday hiatus while the crew was away, daytime roost tracking in King's Gap State Park and Michaux State Forest resumed Tuesday, with the welcome news that all three of our beeping owls are still around.

"Today was a veritable saw-whet owl trifecta!" Aura Stauffer reported. She started tracking Maria, heading for the tree both Maria and Morticia had used this fall. "She wasn't in the tree, but since the snow melted, there were at least 15 pellets under the tree. Some were pretty old, but others were fresh." Those pellets will be added to the others we've collected, to shed some light on fall/winter food habits.

Aura found Maria about 30 yards away, perched about six feet off the ground in mountain laurel. When Aura tracked down Lexi, in the fire break, she too was sitting head-high in laurel. Gemini was again in the white pine forest along Tom's Run, not far from the base of ridge, sitting up in a pine tree.

New Year's Eve Aura headed back out - and got the kind of surprise that's almost becoming commonplace this fall. She found Maria in a pitch pine, "holding on for dear life as the cold front moved in around mid-morning" with powerful winds. And as for Lexi -- when Aura switched to her frequency, she appeared to be in the same tree as Maria, or another just 10 feet away. Aura never got a visual on Lexi, but the presence of whitewash (and a slightly stronger signal) led her to think Lexi was in the neighboring pine.

Some species of owls, notably long-eared and short-eared owls, roost communally in the winter, but such behavior isn't well documented in saw-whets. But we learned a long time ago, nothing's out of the question with these birds.