Tag Archives: raven

Flight Path

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Birds learn how to fly, never knowing where the flight will take them.

~Mark Nepo

This is a brief update on the recent posts where I shared a few sightings of tagged birds – one, a Common Raven in Yellowstone, and three American Oystercatchers on Masonboro Island in southeastern North Carolina. First, the shorebirds at Masonboro. When I got home, I searched the web for information on banded American Oystercatchers and immediately came up with the American Oystercatcher Working Group. This is a conservation group of scientists and resource managers created in 2001 to monitor oystercatcher population dynamics and promote the conservation of American Oystercatchers and their habitats. Their web site has information on reporting sightings of banded birds so I submitted my data. Once they verify your observations and the leg band ID, you receive information on the birds you reported.

Here are the three birds and what we know of their stories…

American Oystercatcher with Band CUU (click photos to enlarge)

CUU was captured and banded on 4/26/16 on Masonboro Island. There have been 33 reported sightings since that time. There are 3 confirmed breeding/nesting seasons on Masonboro (the nest was found); In other years, the bird was seen on Masonboro during the nesting season, but a nest was not observed. Winter sightings were at Dewees Island, near Charleston, SC, in December of 2017 and 2018, a distance of approximately 140 miles from Masonboro.

Banded bird CUW

This is the homebody of the three birds, never having been reported more than 18 miles from Masonboro (on Bald Head Island), even in winter. Captured and banded on 4/26/16 on Masonboro. Reported sightings 43 times. Also has 3 confirmed nests on Masonboro Island and has appeared in that location during the other breeding seasons, but no nest was observed.

Banded oystercatcher CUT

The long distance traveler of the group. Captured and banded on 4/26/16 on Masonboro Island. Re-sighted 56 times. Five confirmed nesting seasons on Masonboro (nest found). Observed in Cedar Key, Florida, every winter since it was banded. That is a distance of about 460 miles one way every year.

The map below shows the apparently consistent winter travels of the three American Oystercatchers.

Range map of the migrations of the three oystercatchers I observed

The type of leg band that the oystercatchers had can be viewed and reported from a distance using binoculars, a scope, or a telephoto lens. That type of information gives a data point for any time someone reports seeing the bird. The “tag” on the ravens in the Yellowstone research project includes color coded leg bands for visual observation and a solar-powered GPS backpack with an antenna that submits the birds’ locations every 30 minutes throughout the day. This combination gives a much more detailed view of the birds’ behavior.

The 70 or so tagged ravens are a part of a study looking at interactions of these intelligent birds with their habitat (foraging and roosting sites for example) and with large carnivores (bears, mountain lions, and wolves). In an earlier post, I mentioned I had found out about this research online and had contacted the lead scientist, Dr. John Marzluff. He identified this bird as the female at Tower Junction (the location where she was captured and tagged) with transmitter 7493-2. She was captured on December 10, 2021 and we observed her on 1/20/22 at Tower Junction, patrolling the parking lot at the pit stop and recycle bins.

Common Raven at Tower Junction showing the solar-powered GPS backpack and color-coded leg bands
The colored leg bands… Left – dark blue over gray, Right – light blue over metal

Her data is now visible on the Animal Tracker app (for iPhone and iPad – search for raven and then scroll down to Tower_Junction_female). She tends to move mostly between Tower Junction and Lamar Valley, a distance of about 12 miles. Her longest flight to date has been to an area north of the park entrance along Hwy 89, a distance of about 22 miles. Some of the tagged ravens have dispersed much farther, with one heading up to the Bozeman area, and another, the record-holder, flying up to Alberta, Canada.

The Tower Junction female raven tends to move mostly between that area (the dark cluster of data points is Tower Junction) and Lamar Valley (map from movebank.org web site).

Is she going to carcasses in Lamar or just stopping at places where there are concentrations of visitors? I would love to be out there and recording data on these birds to see what they are actually doing. It is a treat to get a peek into the private lives of wildlife. But, more importantly, this is valuable information that may help researchers and resource managers make better decisions for protecting these birds and their important habitats.

Frosted Feathers

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It’s not that I like ice Or freezin’ winds and snowy ground. It’s just sometimes it’s kind of nice To be the only bird in town.

~Shel Silverstein

This final post on our January Yellowstone trip shares a few highlights of the birds we encountered. There are certainly way fewer birds in this frozen land in winter, though the thermal features do keep some waterways open for the few waterfowl that remain (or gather there in winter, in the case of Trumpeter Swans). And the activities of wolves and the bottleneck of cold and food limitations do provide sustenance for the avian scavengers – the eagles, magpies, and ravens. Here are a few bird highlights from the trip…

Common Ravens are one of the most noticeable of the winter birds. They are large, noisy, and bold (will try to steal food if you are careless) (click photos to enlarge)

Recent surveys have estimated there are 200-300 ravens utilizing the northern part of the park as habitat. They are frequently seen near areas of concentrated human activity (pit stops, favorite pullouts, etc.) where they are very clever at taking advantage of any potential food items left unguarded. They are also abundant at any carcass, be it a roadkill or wolf kill.

This was my first time seeing a Raven with leg bands and a GPS backpack on in the park (Melissa has seen them on some of her previous trips the past couple of years). We learned that this is part of a study of Raven movements and interactions with wolves being conducted by researchers at the University of Washington.

The sight of Ravens wearing mini-backpacks (satellite transmitters) really peaked my curiosity. The one above was photographed at Tower Junction near the pit toilets and trash/recycling bins. We saw another one (maybe more) flying back and forth with chunks of meat at the bison carcass where we watched the wolves. When I got home I started searching for more information about this study, the Yellowstone Raven Project. The goal is to have about 70 ravens tagged in the park, all wearing solar-powered GPS backpacks with an antenna that submits the birds’ locations every 30 minutes throughout the day. Using this data, researchers are able to piece together the movement of Ravens from sunrise to sunset. There are many things they are investigating about these highly intelligent birds (how do Ravens consistently find wolf kills?; how far do they travel daily/monthly/yearly,?; where are they roosting?, etc.). I contacted Dr. Marzluff, the lead scientist, this week and asked about the Raven above, as I could not find the color code combination of leg bands on the Animal Tracker app, (this free app allows you to peek in on the movements of various tagged animals around the world, including the Yellowstone Raven Project). He promptly responded to let me know that this bird, a female, was captured and tagged on December 10, 2021, at Tower Junction, and has not yet been added to the app. In fact, he was watching that bird the day I emailed him! I’ll try to follow up with him in a few weeks to see what this bird has been up to. It is really amazing to be able to follow research going on in the park (and there is a lot of it!).

A gorgeous Stellar’s Jay at a friends tree stump feeder outside the park

One of the more unusual bird interactions was with a roadkill Ruffed Grouse. We passed it and Melissa radioed me asking if that thing in the road was an animal or just a mud blob or other inanimate object. I wasn’t sure, so when we came back through, I noticed it was, indeed, an animal. I radioed her and she stopped, exclaiming it was a bird, a grouse! We parked and everyone got out to do a spontaneous roadside necropsy. We saw the track trail of the bird approaching the road in the snow and then the tragic result. Melissa poked around and we could see the stomach contents, which included some rose hips (something I had ironically mentioned as a bird food source to the group on one of our snowshoe hikes when we passed one of the shrubs with its bright red fruit). This close up view also allowed us to admire the beautiful plumage and the amazing adaption of the bristles along the birds’ toes which act like grouse-sized snowshoes. Another unique Yellowstone teachable moment!

A roadkill Ruffed Grouse in the coniferous forest near the Northeast entrance (photo by Melissa Dowland)
A more fortunate Ruffed Grouse after it crossed the road in front of Melissa (photo by Melissa Dowland)
Bald Eagle perched along the Lamar River during a light snow fall
A distant leucistic Bald Eagle (leucism is a genetic mutation which reduces pigment in a bird’s feathers) – taken with an iPhone through a spotting scope by Melissa Dowland
A Golden Eagle at its favorite perch overlooking the confluence of Soda Butte Creek and the Lamar River
The most common duck we see in winter – a male Common Goldeneye

One of my favorite birds in the park, anytime of year, is the American Dipper. I sat along the river one day watching one feed from the edge of the ice.

An American Dipper on the edge of the ice along the Lamar River
I think this prey item ls a stonefly

— American Dipper feeding at the confluence of Soda Butte Creek and the Lamar River

I reviewed 7 video clips I made of athe dipper feeding and the average time spent underwater was 6 seconds (five 6’s, a 5, and a 7). The dipper was successful in bringing up a prey item in all seven instances. All were small invertebrates with the exception of one decent-sized macroinvertebrate that I think was a stonefly larva.

So, why do dippers dip? There are a few theories out there: 1) the repetitive bobbing against the backdrop of turbulent water may help conceal the bird’s profile from predators; 2) dipping in this and some other birds may helps it sight prey; 3) the one that an Audubon article I ran across thinks is the most likely is that dipping and the rhythmic batting of those bright white eyelids is a mode of visual communication with other dippers in their typically noisy environment where the usual calls might not be easily heard.

We also saw several other species that evaded a decent photo including Common Redpoll, Gray-crowned Rosy Finch, Black-billed Magpie, Pine Grosbeak, Hairy Woodpecker, Clark’s Nutcracker, Gray Jay, and Red-breasted Nuthatch, Mallard, and Trumpeter Swan.

Thanks for following our winter adventure. Can’t wait to go back!