Tuesday, November 12, 2013

Chasing Broad-winged Hawks at the Idaho Bird Observatory’s Lucky Peak Project

The Idaho Bird Observatory (IBO) runs a banding station on the top of Lucky Peak, on the southern tip of the Boise Ridge. This location hosts a fantastic variety of birds during fall migration, and the IBO crew is there to study them as they move through. According the the IBO website:

“The Boise Ridge is one of only a few known locations in the western U.S. where great numbers of diurnal raptors, songbirds, and forest owls concentrate during fall migration due to the site’s unique geography and habitat mosaic. Lucky Peak is the southernmost tip of the Boise Ridge and the last place woodland birds have shelter and food before crossing over the 50+ miles of the Snake River Plain on their southbound migration. Understandably, many species of forest birds are hesitant to embark on this non-stop flight since cover, protection and food is almost non-existent across the barren plain.”

The IBO crew has had some tremendous finds over the years, including Idaho’s third state record Cape May Warbler earlier this season. After hearing over the weekend of September 14-15, the crew at the hawk watch spotted a group of over 15 Broad-winged Hawks passing by, which is a tremendous find for Idaho. Hoping to see our first Idaho Broad-winged Hawk we headed up to the peak on September 19.

IBO sign 1

Entrance to the IBO banding station at Lucky Peak, Ada County. September 19, 2013.

We visited the IBO site on top of Lucky Peak several times this year, but this was the only trip we managed during their actual banding season. We blogged about what the site is like during the off season earlier this year, and were excited to see the site while it was up and running.

The map below shows where a few key features of IBO’s operation are located. Right in the center of the image you can see the radio towers on the summit of Lucky Peak. The parking area is down slope and to the south of the peak. While the map shows Shaw Mountain Road continuing on to the north, the road is actually gated and can’t be traveled. Visitors to the peak park, and walk a couple hundred yards north to visit the banding area. The walk is fairly level until the first bunch of trees, and then it dips down through a thick patch of bitter cherry, before inclining back up to slightly developed area where the IBO crew sets up their gear. The trail ends in a “T”, with one yurt (I think used as an office) to the east, and another yurt used for banding to the west. In between the banding yurt and the summit many of the crew members set up camp for the season.  Following the trail to the west leads upslope to the summit, where the hawk watch crew counts raptors as they pass by. They have an owl decoy set up in the trees just east of the summit that occasionally attracts Red-tailed Hawks and other larger raptors, and downslope to the east they have a hawk trapping station set up, where they lure in raptors with a bait bird, typically a pigeon, starling, or some other invasive bird.

IBO Map 2

Map of the IBO site on top of Lucky Peak, Ada County. September 19, 2013.

On the drive up, we had already started to see quite a few raptors passing by, including several accipiters (mostly Sharp-shinneds, with a few Cooper’s mixed in), which we haven’t seen on any of our earlier drives up to the peak. As our British birding friends across the Altantic would say, there was lots of vismig (visible migration) on this drive that we’d never seen before. Just before the parking area, there was also a large group of American Crows that seemed to be playing in the breeze.

AMCR 1

American Crows near Lucky Peak, Ada County. September 19, 2013.

AMCR 2

American Crows near Lucky Peak, Ada County. September 19, 2013.

There was a pretty good crowd up there on this trip, a few more than we were expecting for a weekday morning. I’m sure they get way more traffic on the weekends though.

IBO Parking 1

Parking area at Lucky Peak, Ada County. September 19, 2013.

On our walk from the parking area to the banding area, we happened to be passing through the bitter cherry patch just as one of the crew members was arriving to check one of the mist nets. We were a little too late in the day to see high numbers of birds, so this net only had one bird in it. We got to watch as the crew member used a hook to lower the net, and then gently untangled a Ruby-crowned Kinglet from the net.

IBO Mist Net 1

IBO crew member lowering a mist net at Lucky Peak, Ada County. September 19, 2013.

IBO Mist Net 2

IBO crew member untangling a Ruby-crowned Kinglet from a mist net at Lucky Peak, Ada County. September 19, 2013.

IBO Mist Net 3

IBO crew member untangling a Ruby-crowned Kinglet from a mist net at Lucky Peak, Ada County. September 19, 2013.

The satellite imagery from Google maps really doesn’t convey how thick or lush the bitter cherries are on the way to the peak. It’s easy to see how great this little patch of habitat would be for the migrant passerines trying to refuel before the cross the Snake River plain.

IBO Walk 1

Bitter cherry patch at Lucky Peak, Ada County. September 19, 2013.

Here’s the view of the area at the “T” junction in the trail where the IBO crew sets up most of their gear. First, looking west, and second, looking east towards where many of the crew members camp for the season (see if you can spot their tents on the hillside).

IBO Trail 1

Looking east from the “T” junction at Lucky Peak, Ada County. September 19, 2013.

IBO Camping 1

Looking west from the “T” junction at Lucky Peak, Ada County. September 19, 2013.

Just inside the right hand side of the “T” junction is the yurt where they actually band the birds they catch in the mist nets. For each captured bird, they record a variety of information, including species, age, sex, and several measurements. Then, they attach a tiny band with an identification number printed or engraved on it just above the foot.

IBO Banding Yurt 1

IBO banding yurt at Lucky Peak, Ada County. September 19, 2013.

HETH 1

Taking measurements from a Hermit Thrush at Lucky Peak, Ada County. September 19, 2013.

One of the measurements they record is the fat storage the bird has developed. It’s fun to watch how they gauge the fat storage. They roll the bird on its back, and then blow a puff of air on its belly to expose an unfeathered portion of the belly, where both red (for muscle) and yellow (for fat) show through the translucent skin. By examining how much fat is visible, they can get a good sense for how well the bird has accomplished its goal of building fat stores for a long migration.

HETH 2

IBO crew member assessing the fat storage on a Hermit Thrush at Lucky Peak, Ada County. September 19, 2013.

When the crew removes birds from the mist nets, they immediately place them in a small cotton bag, almost like a miniature pillow case. The dark enclosure helps the birds remain calm while they wait to be processed. In this picture, you can see a couple of bagged birds strung up on a line, waiting for their turn to be processed.

HETH 3

Bagged birds waiting in line behind a Hermit Thrush for processing at Lucky Peak, Ada County. September 19, 2013.

When they are through processing the birds, they release them back into the woods. When visitors are around, they typically try to give them a chance to release a bird. This provides an up-close and personal experience that never get to experience during normal field birding.

TOSO 1

Townsend’s Solitaire almost ready for release at Lucky Peak, Ada County. September 19, 2013.

TOSO 2

Ellen releasing a Townsend’s Solitaire placed on her hand by Heidi Ware at Lucky Peak, Ada County. September 19, 2013.

Since we arrived a little too late in the morning for most of the songbird action, and our real hope was to spot a Broad-winged Hawk, we spent most of our visit hanging out at the summit with the hawk watch guys. The views from the summit are incredible. We went on a clear day, and the nearly 360 degrees of view were incredible as always.

IBO Hawkwatch 1

IBO hawk watch crew keeping an eye out for raptors at Lucky Peak, Ada County. September 19, 2013.

IBO Hawkwatch Pano 2

Panorama of the west, north, and northeast views from Lucky Peak, Ada County. September 19, 2013.

Most of the birds pass over fairly high and are hard to see well, but a few, such as this Sharp-shinned Hawk come close enough to provide a photo opportunity.

SSHA 1

Sharp-shinned Hawk passing over Lucky Peak, Ada County. September 19, 2013.

Any birder worth their salt had better notice this owl decoy perched in the trees just east of the summit. It’s been placed here by the crew in hopes of getting the attention of the passing raptors, some of whom will come in closer to investigate, making it easier for the crew to try to identify and sex them.

GHOW Decoy 1

Owl decoy at Lucky Peak, Ada County. September 19, 2013.

It was quite enjoyable to watch migration in action. We never saw any Broad-winged Hawks, but did enjoy great numbers of several other raptors, including a large kettle of Turkey Vultures.

TUVU 1

Turkey Vultures passing over Lucky Peak, Ada County. September 19, 2013.

It was interesting to watch as they vultures searched around for thermals they could glide on to gain altitude and make their journey a little easier. It was quite obvious when the birds were in search of a new thermal, since the entire kettle would begin moving together in one direction, (a behavior called “streaming” by hawk watchers) until they found a good thermal. As soon as the conditions were just right, the entire kettle would break from their straight line approach and soar in all directions on the new thermal.

TUVU 2

Turkey Vultures streaming in search of a new thermal over Lucky Peak, Ada County. September 19, 2013.

TUVU 3

Turkey Vultures soaring in a thermal over Lucky Peak, Ada County. September 19, 2013.

The IBO crew don’t just capture songbirds. They also trap diurnal raptors and forest owls. Their songbird banding season runs from July 16 to October 15 for the first 5 hours after sunrise. Their hawk watch and banding season runs from August 25 through October 31, from 10am to around 6pm. Their owl banding season runs from August 28 to October 28, from sunset to sunrise.

We have not been while they are banding owls yet (fingers crossed for next season!) but did see their hawk banding station on this visit. It’s in plain view from the summit, and is downslope and due west from the hawk watch station. To lure raptors in, they have a captive pigeon, starling, or some other invasive bird dangling on a string, looking nice and tasty. When a raptor comes in for the kill, they are captured in a mist net, and then crew members rush out from the blind to untangle the bird and take it into their blind to take its measurements, band it, and then release it.

IBO Hawkwatch 2

Hawk banding blind at Lucky Peak, Ada County. September 19, 2013.

IBO Hawkwatch 3

IBO crew recovering a captured Cooper’s Hawk at Lucky Peak, Ada County. September 19, 2013.

We had a fantastic time visiting Lucky Peak, and hope to visit more often next season. Lucky for us we live due south of the peak, so the trip is about 20 minutes faster than if we lived further into town.

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