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Last blast – Winter on the Fort Pierre National Grasslands

One last trip to the Fort Pierre National Grasslands! It’s been a couple of weeks…just have had zero time to post photos…but I had a wonderful day trip to the Grasslands. After some rather slow years on the Grasslands, this was a good winter, although the birds were curiously concentrated on the eastern side, mostly in and around some very large prairie dog towns towards Highway 1806.

As always…Rough-legged Hawks predominated, but there were higher numbers of Ferruginous Hawks than I ever remember seeing in one day. Plenty of other “goodies” as well! With that, some photos from my trip a couple of weeks ago…

Rough-legged - Buteo lagopus
Rough-legged Hawk, that was uncharacteristically 1) cooperative for the camera (they’re usually relatively shy!) and 2) on the ground, instead of on a telephone pole.
Bald Eagle - Haliaeetus leucocephalus
Look out below! There’s no doubt that Prairie Dogs are a big attractant to some raptors in the winter. Most commonly, it’s Ferruginous Hawks and Bald Eagles that I see hanging out around Prairie Dog towns, but on this day there were also a number of Bald Eagles. Here one makes an unsuccessful attempt to nail a Prairie Dog, who ducked into its burrow a moment before the photo was taken.
Ferruginous Hawk - Buteo regalis
Ferruginous Hawk in flight. I believe this is a younger birds (not nearly as uniform, gorgeous rusty brown on its uppersides, among other things. Probably my favorite raptor on the Grasslands, other than a Gyrfalcon! Such big birds, and as a bonus…they’re generally more cooperative than other raptors!
Golden Eagle - Aquila chrysaetos
A massive Golden Eagle, sitting on a fence post. There’s no doubt in my mind that these guys have become more and more common over the 20+ years I’ve been birding the Grasslands.
Prairie Falcon - Falco mexicanus
A pretty typical view of a Prairie Falcon on the Grasslands! From a “safe distance” as far as the bird is concerned, and in flight as it warily gives you an eye and flies away!
Rough-legged Hawk - Buteo lagopus
Another Rough-legged Hawk, this time on a fence post. I guess when you see ~100 Rough-legged Hawks in a day, even though they’re generally shy, you’ll come across a few birds that allow a quick photo!
Ferruginous Hawk - Buteo regalis
A mature Ferruginous Hawk in the evening sun. Such majestic birds…Buteo “regalis” is a fitting name.
Rough-legged Hawk - Buteo lagopus
One more Rough-legged Hawk, this one in flight. Until next winter, raptors of the Grasslands! Thanks for another great season!

A typical day on the Fort Pierre National Grasslands

Fort Pierre National Grasslands - South Dakota

Two weeks off of work, winding down as I prepare to return to work tomorrow. It’s been a wonderful (and much needed!) break, with time with the family, and plenty of birding. In two weeks I managed to make it out to central South Dakota three times…more than I normally do all winter! It’s such a magical place for me in winter. Quiet…open…often harsh and unforgiving…yet very restorative for me when I need time alone to recharge.

So what’s the attraction? Central South Dakota? In the dead of winter? Here’s a photo synopsis of what it’s like, all photos from my most recent trip out there last Thursday/Friday.

Fort Pierre National Grasslands - Sunrise
Pre-dawn on the Fort Pierre National Grasslands. Normally I make a (long) day of it, leaving 3 hours before dawn so I can arrive just before the sun rises, and make the most out of short winter days (about 9 hours of sunlight at a minimum). This photo gives you a good idea of what it’s like as you await the sunrise…VAST…open…isolated…and other than barbed wire fences and a few powerlines, often not much of a sign of human habitation. An exciting time as the sun arises, as you just KNOW you’re about to have another wonderful day on the grasslands.
Pronghorn - Fort Pierre National Grasslands
It’s not ALL about birds! While winter raptors are my primary reason for coming to the region, there’s often other wildlife to catch your attention. On this trip I was thrilled to see a large herd of Pronghorn grazing on the rolling hills, just as the sun was rising. Mule Deer and White-tailed Deer are also often seen. Coyotes are certainly around, and I probably see them about every other trip to the Grasslands, but mostly at dawn. They’re extremely shy and difficult to approach.
Buteo Regalis - Ferruginous Hawk - Fort PIerre National Grasslands
There are a few private land holdings within the Grasslands boundaries, but there are more abandoned buildings than any other. In a land that’s often treeless or without any kind of high perches, these abandoned homesteads often are birding hotspots. Here a Ferruginous Hawk is perched next to an abandoned…Packard (?).
Gyrfalcon - Falco rusticolus
RAPTORS are the name of the game on the Fort Pierre National Grasslands, but there’s a definite hierarchy in terms of what I’d love to see!! The Holy Grail bird of the Fort Pierre National Grasslands…a Gyrfalcon! And not only a Gyrfalcon, but an adult Gyrfalcon. In the 20 years I’ve been birding the area, I’ve probably seen about 25 Gyrfalcons. I believe I can count on one hand how many of those have been adults, so I was thrilled to run across one on this trip. I watched from a long distance and took some photos from further away than I normally would, as I wanted to make sure I documented this bird’s presence. I’m glad I stopped so far away and grabbed some photos, because after watching it for perhaps 30 seconds, it flushed and flew away, and I never again found it on this trip.
Greater Prairie Chicken in Flight - Tympanuchus cupido
Why are there so many raptors on the Fort Pierre National Grasslands? Clearly raptors go where the food is. There undoubtedly must be a lot of voles and other small rodents, as that’s what I primarily see birds like Rough-legged Hawks catch. But another attractant to birds like the Gyrfalcon above are all the Ring-necked Pheasants, Sharp-tailed Grouse, and Greater Prairie Chickens that are around. It’s a popular hunting location for all of those species, and given that surrounding private lands often release birds (pheasants) for hunting, there’s never a shortage of any of those species. The native Sharp-tailed Grouse and Greater Prairie Chickens are VERY wary as a result of the hunting pressure, and I have few close photos of either species. On this trip I was very happy to get my first ever flight photo of a Greater Prairie Chicken. With the recent heavy snow, many of the game birds were struggling to find foraging grounds, and were concentrated along the roads more than usual.
Ring-necked Pheasant - Phasianus colchicus
Speaking of Pheasants…they are widespread in the area, but are probably less common on the Grasslands themselves than on the surrounding private lands.
Bald Eagle - Haliaeetus leucocephalus
You’ll see both Bald Eagles and Golden Eagles on the Grasslands. Golden Eagles are more often seen (they were downright common on the three recent trips I took), but even far from any open water, you will also often see Bald Eagles. I’m aware of at least 4 different nests just to the south of the Fort Pierre National Grasslands themselves, near the Presho area. This photo is along the Missouri River just to the north of the Grasslands, a stronghold of the species in the winter months.
Prairie Falcon - Falco mexicanus
A Prairie Falcon in flight. They’re definitely a larger bird than the American Kestrels you see a lot in the summer months (and to a much lesser extent, in winter). They’re larger than the Merlins you sometimes see on the Grasslands (including one I saw Friday). But they share the same “falcon” characteristic when they take flight, with much faster wingbeats than all the Buteo hawks in the region, and a more tapered wing. Couple the relatively large size and that classic falcon flight pattern, and Prairie Falcons OFTEN get my heart racing as I’m thinking that bird flying up in front of me may be a Gyrfalcon! On a typical day on the Grasslands though, I’m lucky if I see a Gyrfalcon, yet I almost always see 3 or 4 Prairie Falcons. Usually they’re pretty shy, but there’s been one hanging around County Line Road on the grasslands this winter that’s uncharacteristically curious. He’ll flush when you get anywhere close, as do nearly all Prairie Falcons. But then he has this habit of circling me one or two times before finding a different perch! It’s not often I can grab a Prairie Falcon in flight, so I’m pretty happy to have seen this guy on this past trip.
Rough-legged Hawk - Buteo lagopus
Always by FAR the most common raptor on the Fort Pierre National Grasslands in winter…a Rough-legged Hawk. I didn’t stop and record each one in eBird as I often do. But on a trip to the area the week before I saw nearly 50 of them, and I would suspect I tallied a similar number on this past trip. Gorgeous birds, and quite variable in plumage, although this is the typical plumage that you see.
Buteo jamaicensis - Red-tailed Hawk
The Fort Pierre National Grasslands are mostly treeless, and even during the summer months I’ve found Red-tailed Hawks are typically concentrated in the few wooded ravines, shelterbelts, or abandoned farmsteads in the area. In winter, those site tendencies are even more pronounced. Many Red-tailed Hawks move further south for the winter, and I find MANY more Red-tailed Hawks just south of the Grasslands (such as the Presho area) in winter than I do on the Grasslands themselves. However, over the 20+ years I’ve been birding the area, it’s quite obvious to me that more birds are overwintering in the region than used to. Similarly, 20 years ago it wasn’t common to find Western Meadowlark overwintering in any numbers, but on this past trip, there were a few spots where I stirred up a dozen or so Meadowlarks hanging out together. More Red-tailed Hawks, more Meadowlarks, fewer Gyrfalcons….that’s my impression of what’s happened over the last 20 years.
Golden Eagle - Aquila chrysaetos
The one photo here that’s not from last Thursday/Friday, as this was taken on the Grasslands 2 days before Christmas. My impression is that BOTH eagle species are getting much more common on the Grasslands. I have few if any photos of them 10 to 20 years ago, but now I typically see 6-10 each time I go out.

South Dakota Winter – Best…photo…day…ever!!

Since I’m still not allowed to go back to work, I spent yet another day birding in the central part of the state. It was a day with lower overall numbers of raptors. I saw far fewer Rough-legged Hawks than normal. I didn’t see any Gyrfalcons, Snowy Owls, Short-eared Owls…some of the “goodies” you often find.  But birding and photography is funny! I’ve had awesome birding days where I got very few photos. Today was the opposite…not huge numbers of birds, but some really wonderful photo opportunities.  Here’s some pics from the day with a little info for each:

Prairie Falcon - Falco mexicanus

While it wasn’t a banner day for many of the “usuals”, I saw more Prairie Falcons (7) than I remember seeing in one day. “Seeing” and “photographing” are two very different things, however. Prairie Falcons are about THE shyest, most skittery raptor I know of. Today however I got a real treat. While birding in Jones County, I saw a falcon on a telephone pole. As I always do, I first stopped a long distance off, grabbed the binoculars, and tried to identify it. Definite Prairie Falcon. I then started to approach, and as ALWAYS happens with Prairie Falcons…it flew off LONG before I got into camera range.  But then something funny happened…it turned around. Still not expecting much, I got out of the pickup and grabbed my camera. But he came closer…and closer…and closer, and I soon realized he was going to fly RIGHT over my head! I couldn’t have asked for a better setup…bird approaching on a clear day, sun in the perfect position to get nice lighting on him, and he was CLOSE…closer than I think I’ve ever been to a Prairie Falcon. He passed right overhead, and then proceeded to…well…check out the next photo.

Prairie Falcon and Lapland Longspurs

As the Prairie Falcon flew towards me and over the field behind me, there was an eruption of Lapland Longspurs, Horned Larks, and quite a few Snow Buntings. THAT got the Prairie Falcon’s attention. Instead of continuing to fly past and away from me, he again turned, and started to interact with the mixed flock of birds. At points it was almost like he was herding them! He never came as close as he did for the original overpass, but he offered some more really nice photo opportunities, and with several shots I captured some of his potential prey in the background. Despite scaring the flock of little birds, I never did see him actually make a strong move towards one. After a little while he seemed to get bored, and went back to a nearby telephone pole.

Bald Eagle - Haliaeetus leucocephalus

I remember when I first started birding, and came across my first bald eagle. It was the winter of 1999/2000, and I thought it was the most magical experience I’d ever had! In the 20 years since then, Bald Eagles have become, well…downright COMMON! When I bird the central part of the state in winter, I always run across them. There are several nest locations in the area, and I always KNOW there will be Bald Eagles in a few select spots. One such spot is near Presho, and when I drove past it, sure enough…there were 4 Bald Eagles in a small grove of trees, 3 adults and one sub-adult. Given how often I’ve seen eagles there, I’m sure they’re the same ones, or the same family. As such, perhaps today they gave me a pass and stuck around and let me photograph them! Three of the birds were hidden within the branches or were towards the back of the grove, but one bold individual adult just stared at me from his perch, wondering what I was up to. I watched him for quite some time, before he did what many raptors do right before they’re about to take flight…he pooped and positioned himself to fly off. Those can be truly wonderful moments for photography, with some truly angelic poses. This is now probably one of my favorite Bald Eagle photos that I’ve taken (and I will add it to the hundreds of other Bald Eagle photos I already have!).

Ferruginous Hawk - Buteo regalis

Not only did I have a banner day for Prairie Falcons, but I also saw more Ferruginous Hawks than I normally do…5. 4 of them were in Jones County, and the reason was obvious…Prairie Dogs. Without exception, all 5 Ferruginous Hawks on the day were in and around prairie dog towns. I do have a few photos of other color morphs, but today all were the same light color morph (the most common one). Some, like this bird, are SO snowy white on their undersides with barely a hint of marking, that I sometimes mistake them for Snowy Owls as I approach from a distance! One of my favorite bird species, hands down, and there’s a bonus with Ferruginous Hawks…they are MUCH more cooperative for bird photographers than nearly any other raptor species on the grasslands!

Ferruginous Hawk - Buteo regalis

My longest birding lens, and the lens with which I’ve shot at least 95% of my photos with over the last 15 years, is a Canon 400mm 5.6L. Yes, it’s now 15 years old. But it has always been one SHARP lens, with some incredible detail when you get a bird filling the frame of a photo. The downside…most birders use a 500mm or 600mm, WITH a tele-extender. In short…they have a LOT more “reach” than I have! Because of that I’ve 1) learned how to overcome using a somewhat shorter lens, and 2) learned to accept I’m going to miss some shots where more length is required. However, that latter point is all bad. While I like photos with the birds filling the frame, I also like photos showing the bird interacting with its environment. Here, I came across another Ferruginous Hawk on a prairie dog town. I was nowhere near close enough to get a frame-filling photo, so instead worked on capturing his behavior as he “worked” the prairie dog town, alternating between sitting on the ground or a fence post, and flying through the prairie dog town looking for prey. I never did see him capture anything but it was fun to watch the behavior and try to catch it in a photo.

Golden Eagle - Aquila chrysaetos

Speaking of “environment” photos…here’s a pair of Golden Eagles at the “usual” hangout. By “usual” I should say nearly ALWAYS. This was taken south of Presho, in one of my favorite birding locations. This fallen down structure nearly always…ALWAYS…has a golden eagle sitting on it! Well, during winter and in the morning, that is. When I make trips to this area, I usually try to make it to the Presho area by dawn, and this is one of the first areas I look for raptors. And I swear, 95% of the time when I drive past this fallen-down structure, there’s a golden eagle sitting on it. Today there were two eagles! This kind of winter-range site fidelity is pretty cool, and it’s not just these Golden Eagles. About 5 miles northwest of here, west of Presho, is a farmstead where I ALWAYS find a Northern Shrike in winter. ALWAYS. Has to be the same one, right? Again, not a frame filler of a photo, but I love showing these birds at their favorite hangout.

Rough-legged Hawk - Buteo lagopus

Ok, this one is cheating a bit. This one isn’t from Wednesday, January 9th, it’s from Friday, January 4th. Rough-legged Hawks aren’t as numerous this winter as they can be many winters, but there still are always at least a few hanging around. Here’s one taking flight in the early morning sunlight.

 

Photo / Haiku of the Day – Dakota Prairie Falcon

Prairie Apparition

Prowling Dakota skies

A flash across desolate plains

bound for the horizon

Prairie Falcon - Falco mexicanus

When I head to the central part of the state in winter to photograph raptors, I usually do come across a handful of Prairie Falcons during the course of the day. Falcons in general seem to be camera shy, but these guys are particularly difficult to photograph. They tend to flush long before I can get within camera range. There’s always that oddball individual bird, however, and this is one of them. As with every other Prairie Falcon I come across, he DID flush early, while I was still perhaps 50 yards away. However, he was curious! I’d given up on him, but to my surprise he started circling back towards me. I stopped the car and got my camera ready, and was rewarded by a flyby at perhaps 30 feet up, right along the road past my car. One of my favorite falcon shots, given the difficult I’ve photographing these guys. I also love the pose, with the eye contact and the warm morning light.

One more trip – Rocks and Birds

It was a beautiful weekend in much of South Dakota, so much so that the lure of one last rockhounding trip was too much for me to pass up.  With projected highs near 60, and just as importantly on the windswept plains of South Dakota, a lack of a wind, it seemed like the perfect day to roam around the Buffalo Gap National Grasslands. An added treat of birding the western part of the state at this time of year…all of the winter raptors that are arriving!

I started out rockhounding, and could tell it was going to be a great day.  I tried a little bit different spot, and immediately found it wasn’t as “picked over” as my typical spot near Kadoka.  Right away I was finding many bubblegum agates, some beautiful rose quartz, some amber-colored honey agates, prairie agates, and some big chunks of petrified wood. I also found several coral and shell fossils, including one cute little bubblegum agate with a crisp imprint of a shell on the back side.  The highlight…after only 10 minutes, I found a gorgeous Fairburn agate with an unusual, rosy-colored quartz center.  That piece alone would have made the trip worth it.

While I spent most of the day rockhounding, I also kept my eyes open for the arriving winter raptors. Rough-legged Hawks, as always, were in abundance in parts of the Grasslands. Ferruginous Hawks, Golden Eagles, a prairie falcon, and plenty of Red-tailed Hawks rounded out a day that finished with the spotting of a gorgeous, pure white, unbarred Snowy Owl on the drive back home. A great “last blast” out on the Grasslands, before the really cold South Dakota winter hits.

Fairburn Agate - South Dakota

A gorgeous Fairburn agate as I found it on the Buffalo Gap National Grasslands. On average this year, I’d say I find one Fairburn for about every 15 hours of looking, so it’s always a wonderful treat. This one was so unusual, in terms of that grogeous rosy center surrounding by the fortification banding.

South Dakota Agates, Jaspers, Petrified Wood, Quartz

The material I brought back. You can collect on the Buffalo Gap National Grasslands, but 1) only for private collections (no selling of material), and 2) can collect up to 25 pounds of material in a day. Given I usually only keep the smaller pieces (most are 2″ or less), that’s not a problem! But on this day, there were some BIG pieces of petrified wood I was tempted to bring home! If I had done so though, a couple of them would have used up my 25-lb allotment! Hence sticking with my “usual” agates and other material.

Where did the Fort Pierre National Grasslands raptors go?

Central South Dakota - Raptor Sightings

Winter raptor sightings in central South Dakota over the last 5 years. The Fort Pierre National Grasslands themselves used to be “the” hotspot for winter raptors, including great chances for rarities like Gyrfalcons and Snowy Owls. In recent years, raptor numbers are incredibly low compared to areas just south of the Grasslands, in and around Presho and Kennebec. Click on the map above (or any other image) for a larger view.

I still vividly remember the first time I had ever visited the Fort Pierre National Grasslands.  It was 2000, and I had been bitten by the birding bug.  Hard. Much of my free time was spent birding and taking photos, and as a new birder, there certainly were plenty of “new” birds to discover, just around my home town of Brandon.  One of my friends at work was an avid, lifetime birder, and he not only helped with identification of the birds in my (quite poor!) early photos, but he also helped to stoke the birding fires.  That was very evident when reports came in of a Gyrfalcon on the Fort Pierre National Grasslands.  In the years since, the Grasslands have become known as a wonderful location for finding these very rare winter visitors, but at the time, it was something rather novel.  Given that my lifetime birder friend had never seen a Gyrfalcon, I knew this was something special for a birder and I was excited to try to find it. Thus began 16 winters of making periodic birding treks to the Grasslands.

It couldn’t have been easier on that first visit.  The famed “Pheasant Farm Gyrfalcon” was hanging around a farmstead that raised pheasants for hunting operations in the region.  I talked with Doug B. in Pierre, a great birding contact who also helped a lot in my early birding years, and he provided directions (we’re WELL before cell phones and google maps here!).  He had said that he was likely to be around that location early on a Saturday morning, so I made plans to get up ridiculously early and drive to the Fort Pierre National Grasslands and arrive at that spot just after dawn.

Rough-legged Hawk - Buteo lagopus

The ubiquitous Rough-Legged Hawk, once seemingly found on every other fence post and telephone pole on the Fort Pierre National Grasslands. However, for the last 5 years, they’ve been curiously absent.

That cold December day came, I set the alarm, packed up my equipment at 4:30, and started the 3+ hour drive.  My timing was good, and I arrived on County Line Road right around 8:00 AM. As I reached an old abandoned schoolhouse that marked the location close to the pheasant farm, I saw a pair of cars.  I got out, saw Doug B., and asked if they’d seen the Gyrfalcon.  He smiled, and pointed to the top of a nearby telephone pole, and there it was!  My first Gyrfalcon, about as easy a “capture” as a birder can ever hope for with such a rarity!

From that day forward, I was hooked on the Grasslands.  Given that it’s about 3 1/2 hours from home, it’s not a love of convenience!  But I quickly learned to appreciate the isolation and beauty of the area. Most days on the Grasslands, you run into very few people, and there are times after a nice wet period where the beauty of the grasslands and flowers can be really spectacular.  But of course, it’s the birding that was the main attractant for me, and my GOODNESS what incredible birding there was.  Winter in the middle of South Dakota may not sound like a time for vibrant bird life, but the Fort Pierre National Grasslands was building a reputation as a magnet for raptors. This not only included one of the best chances in all of the lower 48 states to see a Gyrfalcon, but also a diverse list of other raptors that spent their winter months on the Grasslands.  Rough-legged Hawks were found in extremely high numbers, such that many times it was quite rare to drive more than half a mile on County Line Road and NOT see a Rough-legged Hawk hanging out on a telephone pole or fence post.  It’s the first place I saw a massive, incredibly powerful Golden Eagle.  It’s the place where I first saw a Ferruginous Hawk, a bird with such a brilliantly white underside that from a distance I thought I was about to see my first Snowy Owl.  It wasn’t that year, but later the Fort Pierre National Grasslands WERE the place I saw my first Snowy Owl, including one incredible year where Snowy Owls were practically as abundant as the ever-present Rough-legged Hawks. It’s the first place I saw a Prairie Falcon, a bird that for a long time was a photographic nemesis for me given their predilection for flushing and flying away whenever I got within 1/4 of a mile of one.  It’s the first place I saw a Short-eared Owl, a summer-time encounter where two adults were tending 4 younger birds.  That encounter concluded with an adult circling me for several minutes as I stood outside my car, resulting in one of my most memorable photo opportunities (and a new Canon DSLR camera body, thanks to the photo winning a nationwide Canon photo contest!).

Winter Sightings - Rough-legged Hawk

Winter sightings of just Rough-legged Hawks. Note the incredibly dense populations near I-90, and the sharp drop off towards the Grasslands in the north.

There have been days on the Grasslands where a full, complete day of birding could simply consist of driving back-and-forth on County Line Road and occasionally taking one of the small gravel roads that connect to it.  One could potentially stay within a relatively small driving area of 10 to 20 square miles, and find dozens, upon dozens, upon dozens of raptors.  Since that first day in 2000, I’ve had some of my most memorable photo experiences on the Fort Pierre National Grasslands in winter, including finally getting a close shot of a Prairie Falcon, having a curious first-year Gyrfalcon circle me in curiosity in much the same way that Short-eared Owl did years before, capturing a photo of the massive wingspan of a Golden Eagle as it takes flight, and finally capturing my first decent photos of a Snowy Owl.  During all my winter trips to the Fort Pierre National Grasslands, I learned to appreciate not only the Grasslands themselves, but the area south of the Grasslands.  I’d necessarily drive the I-90 corridor past Reliance, Kennebec, and Presho to get to the Grasslands themselves, and couldn’t help notice all the raptors in the area.  Soon, my “Grasslands” birding trips became “central South Dakota” birding trips, with days where I’d usually spend mornings in the Presho area and afternoons on the Fort Pierre National Grasslands.  Birding life was good, and many a cold, dismal, South Dakota winter was saved by the vibrant display of life that was always available on the Grasslands.

And then…something happened.  It started about 5 years ago, when I planned one of my “usual” winter trips to the area.  The first half of the trip was the same as always…plenty of raptors of all kinds in the Presho area, and plenty of photo opportunities.  However, as I headed north towards the Grasslands themselves, the birds disappeared. Given my past history of finding winter raptors on the Grasslands, I kept expecting the birds to show up around the next corner, but…they never did.  There was an occasional raptor here or there, primarily Golden Eagles or Ferruginous Hawks, but the incredible density of Rough-legged Hawks, the species that once made up a good 80% of all the raptors found on the Grasslands, was simply absent.  Almost TOTALLY absent.

Greater Prairie Chicken - Tympanuchus cupido

A Greater Prairie Chicken on the Fort Pierre National Grasslands. Whatever the cause of the raptor decline on the Grasslands, it doesn’t appear to be because there’s been a noticeable decline of gamebirds.

That first winter after the raptors disappeared, I just speculated that something happened to the prey base that attracted the raptors. When driving the Grasslands, you always saw plenty of Ring-necked Pheasants, Greater Prairie Chickens, and Sharp-tailed Grouse.  There were several times where I’d sat in awe as a Gyrfalcon dive-bombed pheasants in search of a meal, and clearly the gamebirds in the area were one thing that attracted raptors.  There didn’t seem to be any obvious crash in the populations of these three gamebird species. The famed Pheasant Farm near County Line Road had stopped raising pheasants, but that’s such a local phenomenon that it couldn’t explain the drop in raptors across all the grasslands.  Indeed, this winter I visited the Grasslands a couple of days after Christmas, when a massive storm had coated the region in snow and crusty ice.  I ran across truly massive groups of Sharp-tailed Grouse and Greater Prairie Chickens, milling about in the open and looking for foraging spots in the ice-locked vegetation. Yet despite all the gamebirds that were out, raptors were again curiously absent.  I didn’t spot a single Rough-legged Hawk on the Grasslands themselves, despite easily finding over 30 earlier in the day down by Presho.

If not a decline in gamebirds, what else?  One factor that may play some role is the loss of some truly massive prairie dog towns in the region.  On County Line Road itself, there have always been a few locations for prairie dogs.  Not all raptors target prairie dogs, but Ferruginous Hawks certainly key in on prairie dogs, and prairie dog towns.  Over the last several years, many of the prairie dog towns in the area have disappeared.  Those outside of the administrative boundaries of the Fort Pierre National Grasslands themselves are fair game for poisoning, to clear the land of these “pests” (don’t get me started).  The largest prairie dog town I knew of in the area was on the east end of County Line Road, just outside of the Fort Pierre National Grasslands itself.  It stretched for almost a mile on the north side of the road, with more scattered spots on the south side of the road.  A few years ago, that entire area was clearly poisoned, and the massive colony is gone.

However, the decline in prairie dogs also fails to fully explain the decline in raptors.  There are NO prairie dog towns down by Presho and Kennebec, yet raptors of every kind are still found there in incredible numbers. Perhaps it’s a decline in the small rodent population in the area? For a raptor such as a Rough-legged Hawk, mice and voles make up a huge part of the diet.  Could there have been some cyclic decline in small rodent numbers on the grasslands?  That was my initial thought, but it’s been 5 years since the noticeable and sharp decline in raptor numbers.  You wouldn’t think some repetitive cycle of boom-and-bust rodent populations would be in “bust” mode for so long. Perhaps it’s related to the Prairie Dog poisoning? Could that have also had an impact on small rodents in the area?

A Black-tailed Prairie Dog. There’s little doubt number of these guys HAVE declined around the fringes of the Grasslands, given active poisoning programs.

One other major prey source in the area, particularly for Merlins and Prairie Falcons, are the sometimes huge flocks of Lapland Longspurs, Horned Larks, and Snow Buntings that are found in the area in the winter. The vast majority of Merlin sightings I’ve had in South Dakota have been on the Grasslands themselves or in the Presho area.  During my last trip over Christmas, the first raptor I saw at dawn was a Merlin munching on a freshly caught Horned Lark by Kennebec, and I’ve had numerous other occasions over the years where I’ve seen Merlins feeding on Horned Larks or Lapland Longspurs.   You do see roving flocks of Longspurs, Larks, and Snow Buntings on the Grasslands,certainly enough to capture the attention of a raptor that’s passing through, but the numbers of those potential prey species have seemed higher in the Presho/Kennebec area in recent years.

The maps that are shown in this post are indicative of the raptor numbers on the Fort Pierre National Grasslands vs. the I-90 corridor in recent years. These are all actual sightings made by myself over the last 5 years, and recorded in eBird.  During each and every trip I’ve made in the last 5 years, I take the same general routes. I start in the Kennebec/Presho area around dawn, by mid-morning start to work my way up through the Grasslands themselves, and then start to head back down south again by mid-afternoon. It’s clearly not a precise, spatially distributed sample of the space shown on the map, but over the last 5 years, I have driven most of the roads in a rectangle bounded by Highways 1806 and 273 on the east, an area typically no more than 5-8 miles south of I-90 south of Presho, and Kennebec, westward to Highway 83 and a few miles to the west (particularly around the Sheriff Dam and Richland Wildlife Area, and northward to County-Line Road itself and a few miles north of it.  Good roads are few and far between in parts of the area, particularly north-south roads that take you from Presho northward into the Grasslands.  As a result, the maps here tend to show the 2 major north-south gravel road that connect the two areas, as well as other more easily traveled roads in the area.

Gyrfalcon - Falco rusticolus

A Gyrfalcon taken during the “Golden Years” on the Fort Pierre National Grasslands. This is a very dark-phase juvenile, and I’ve never seen one quite like this. The Grasslands may still be a good spot to try to find this mega-rarity, but it’s not an ideal spot for other winter raptors any more.

I wish I had eBird recordings for the “golden years” on the Grasslands, prior to this last 5 year period, something against which these maps could be compared.  I DO have a vast number of raptor photos taken on the Grasslands themselves from 2000 to present, with most of those from 2011 and earlier.  What’s clear from these maps, however, is just how sharp a delineation there is between the I-90 corridor, and raptor numbers to the north on the Fort Pierre National Grasslands themselves.  On the map at the top that shows all raptor sightings I’ve recorded, note the one north-south road that extends up from the I-90 corridor, about halfway between Presho and Vivian. That’s my main path for getting north, and while there are plenty of raptor sightings south of the Grasslands, those sightings drop off sharply almost exactly at the Grassland boundary itself.  On EVERY trip over the last 5 years, I will drive County line Road, an east-west road along the county boundary (visible towards the north side of these maps).  Once THE hotspot for raptors, in the last 5 years, I have very few raptor sightings of any kind along this road.  Rough-legged Hawk sightings on the Grasslands are incredibly small when compared to the area just to the south of the Grasslands. Red-tailed Hawks and Northern Harriers have always seemed to be much more abundant in the southern part of this area, but in recent years they are almost completely absent once you get 4 or 5 miles north of I-90.  Bald Eagles are often incredibly abundant in and around the Presho area.  I have had days where a dozen or more Bald Eagles are sitting in one concentrated area, and there are also at least 3 active Bald Eagle nests that I’ve found in and around the Presho and Kennebec area.  I have a few Bald Eagle sightings around the Grasslands, but that’s certainly dwarfed by how many have been found in and around Presho.

There are some species that are more evenly distributed in the area.  Golden Eagles are a species I’m almost certain to find on any trip to the area, and it doesn’t seem to matter whether I’m on the Grasslands, or in the Presho/Kennebec area.  Prairie Falcons also seem rather randomly distributed, as they seem rather unpredictable and likely to pop up just about anywhere on this map.  Ferruginous Hawks also seem rather even distributed.  Is there something in common about these species that may make them more likely to be found on the grasslands? Golden Eagles and Ferruginous Hawks are much more likely to key in on mammals, including rabbits and other larger mammals.  Perhaps if it is a population crash of small rodents, they’re still on the Grasslands as they don’t depend on those smaller prey as much as Rough-legged Hawks or other raptors. Prairie Falcons can feed on a variety of prey items, including small birds like Horned Larks, and even large birds like Greater Prairie Chickens.  Perhaps they too would be less sensitive to a decline in small rodent numbers.

I’ll continue to make my winter treks to the central part of the state, including visits to the Grasslands.  Given that the Grasslands themselves are still the location where I’ve seen most of my Gyrfalcons over the years (including the years prior to the data represented in these maps), that alone is clearly worth the time!  Hopefully over the next few years the Grasslands recover from whatever “ails” it in terms of supporting winter raptor numbers.

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