Tracking Cretaceous Birds in South Korea: Goseong Dinosaur Tracks

Hello Dear Readers!

I'm excited to continue with our tale of Cretaceous tracks in South Korea! September 15 was our day to check out the coastal dinosaur track sites in Sangjogam County Park, a heritage site. This was a track site that Dr. Richard McCrea had visited back in 2000 on his first trip to South Korea. He said to me "I did not expect that I would ever get a chance to visit this site again."

A LOT had changed since Rich's visit in 2000. At that time the area was newly discovered and in the process of being documented. Let's just say, the progress made on the site was impressive!

After breakfasting and grabbing some Starbucks (science runs on caffeine all over the world), we drove to the parking area next to the coastline. We were immediately greeted by a great sauropod sculpture surveying the gorgeous shoreline.

"I am Lord/Lady of all I survey!" said every sauropod everywhere.

The entire area around the Goseong Dinosaur Museum was developed to celebrate the dinosaur track sites. The sidewalks also celebrate their fossil heritage.

Getting ready leave the walkway to stroll along the beach to see the sauropod tracks.

Of course, a sandy beach is a glorious place to look for present-day bird tracks. Today was a day for gull tracks.

One of these days, I'll be able to afford a decent lens for photographing birds. September 15 was not that day. Neither is today, actually.

This was the best picture I could get of one of the gulls roaming around the beach that morning. It's carrying a mussel in its beak, so the appearance of a black ring on the bill is artificial. I also didn't pack my binoculars that day, so my identification of this gull is "gull." The gulls did leave some nice trackways.

The sand is damp enough that the webbing impressions are preserved. We can clearly see the claw impressions and occasional toe impressions.

There was also some interesting behavior exhibited by the gull tracks. Check out this landing trace of a gull: you can see the long drag mark left by the hallux (backward-facing toe) running down the middle of the scuffed-looking footprint. I used this image for my weekly Twitter ichnology game #NameThatTrack.

Of course, I couldn't spend all day on the beach taking pictures of modern footprints (although this would be a worthy ichnology project.) We made our way over to the Goseong Track Site.

Goseong Dinosaur Track Site in Sangjogam County Park. Drs. Kim Kyung-soo (left) and Richard McCrea (right) taking initial observation notes.

The most obvious trackways on the site are sauropod trackways.

The circled areas are the sauropod tracks. Scalebar in the picture is 10 cm.

Close-up of the sauropod tracks with a 10 cm scale (and my feet) for scale.

While we were on the site, we found ourselves in the middle of a couple of school groups doing a geology-based field trip assignment and tour on the track site. We ended up being part of the tour, with the students watching us take photos and asking us questions. We also ended up signing autographs on their site brochures! That felt...odd. I mean, I was not involved with finding or developing the site, but I suppose they appreciated the chance to interact with dinosaur track scientists on the site.

Drs. Martin Lockley and Richard McCrea somewhere in the middle of the tour group!

There are several track types on the Goseong Track Site. Here is an ornithopod trackway, with the tracks outlined with dashed lines.

With coastal rock exposures, particularly those that are periodically covered by tides, we don't expect that tracks will "last" that long. Tides are powerful, running sand and shells over track surfaces. They also form tidal ecosystems: it's not uncommon to see dinosaur footprints doubling as tidepools. Given that tidal-influenced areas are generally high-energy, I was not expecting to see bird tracks at this site. I moved a little farther away from the shoreline to check out some fine-grained surfaces. I was not disappointed!

They are shallow, but there are small bird tracks!

It was an overcast day, so the light was fairly dim and there few shadows being cast on the track surface. These were great conditions for getting photogrammetry images of the sauropod and ornithopod trackways, but the dim light made seeing bird difficult. Like I've mentioned before, lighting is everything when it comes to recognizing tracks.

The Goseong Track Site was impressive for another reason: the level of resources and development that went into making the site accessible to the public. When I show these images, remember that only 17 years prior this area didn't have the track sites developed or a dinosaur museum built.

First, there are the extensive walkways built along the coastline so that people can look over the track surface. There are several kilometers of these walkways! At key points along the walkways are informative signs that direct visitors' attention to key geologic and paleontologic views.

Editorial Note: OK, friends, I need to go on a bit of a rant. Look at this sign. It gives out science information without talking down to the reader. Do you see any cheap, lazy Jurassic Park-themed lettering? Any sensationalized attempts to use giant waves in "storytelling"? You do not. I did not see ANY sign of the North American-style insulting "tourism marketing" in South Korea. This is because the organizations that made these signs actually respect the intelligence of the people who are visiting natural history sites. They don't assume that there is "too much science" in the information provided, or that the public needs to be "talked down to."  Each time I see a fossil heritage site that blatantly uses Jurassic Park imagery and/or sensationalized "stories" to interpret a site, I assume the organization that created those signs does not respect their visitors OR the fossil heritage they exploit. Respect for fossil heritage or those interested in natural history isn't even on the radar for those particular organisations: fossils are merely a thing to selfishly use, and the public are just their dupes with wallets. It makes me feel angry and ill. Oh, and the fact that, since Rich's 2000 visit, a museum and outdoor interpretive sites had been fully developed? It is extremely frustrating to see the slow progress of getting similar dinosaur track sites developed in North America. We've been in the Peace Region full-time since 2004 and we still struggle year-to-year to have fossil heritage conservation funded.

We hiked up to another track site that was not yet interpreted: one of the aspects of coastal geology is that it changes a lot, with new rock surfaces constantly being exposed. Rocky cliffs are also a tricky place to do ichnology, mostly because of the ever-present threat of those tracks using gravity to make face-time with you. Here are some bird tracks exposed on the underside of a rock exposure. We couldn't get a close-up view of them, but we could tell they were the ichnogenus Jindongornipes.

The preservation of these large bird tracks (Jindongornipes) is amazing! We can even see webbing impressions!

Rich attempting photogrammetry on the Jindongornipes tracks. It becomes more tricky when you can't get something for scale on to the track surface.

We continued our hike up from the coastline boardwalk to connect with the outdoor trails and displays of the Goseong Dinosaur Museum. Again we were treated to a glorious sight: great outdoor displays that did not shy away from interpreting science.

The boardwalk trail joins up to the Goseong Dinosaur Museum outdoor trails.

Um, friends? There's a Utahraptor watching you!

All of the outdoor dinosaur sculptures were time-appropriate to the age of the tracks exposed at the Goseong Dinosaur Track Site: Early Cretaceous in age, roughly 120-100 million years old. We did not see any Tyrannosaurus rex or Triceratops models, which are 66 million years old. This was another sign (to me) that the Goseong Dinosaur Museum wasn't relying on sensationalism (a.k.a. all cool dinosaurs are T. rex!) to interpret their fossil heritage.

The Goseong Dinosaur Museum also had some fun with their outdoor displays. I love this cartoon bird pointing out the names of the bird tracks.

We stopped for lunch with the Goseong Dinosaur Museum curator at the museum's cafe, and were treated to a wonderful beverage: quince tea that the curator made! We found out the recipe, but darn it! We can't seem to find quince anywhere in grocery stores. The hunt continues!

After lunch we spent some time in the collections facility of the Goseong Dinosaur Museum, collecting data, photogrammetry images, and track slab tracings.

Dr. Martin Lockley making a plastic sheet tracing of a bird track slab.

Sometimes you meet the local fauna when you work on tracks. Here's a wolf spider, who was not impressed when I disturbed its cozy hideout. It was ceremoniously moved outside.

One of the many bird track slabs in the Goseong Dinosaur Museum collections.

Drs. Martin Lockley (left) and Richard McCrea (right). If you like groaner-puns, these are the two to go into the field with.

We worked until evening, and then went out for dinner at a restaurant whose name roughly translates to "The Broken Bone Restaurant." It was a great dish of stewed meat on the bone, served with fried rice.

The Broken Bone Restaurant. 

It's no secret that I like spicy foods. Do you see the green chilis on the dish to the left? Up until this point, I had been munching on these peppers like they were candy. Tonight was the night that I found out there are two types of long green chilis: mild and spicy. I caused a great deal of amusement as I sat there, eyes streaming, face flushed, laughing at my luck of the draw. I found out that the smooth-skinned green chilis are the mild ones, and the green chilis with wrinkled skin near the stem are spicy. Live and learn!

The next day we were scheduled to give public talks on our work in Canada and South Korea at the Goseong Public Library! Tune in next week to find out how our talks went!

Tracking Cretaceous Birds in South Korea: Chinju Innovation City and Sangcheong-gun

Hello, Dear Readers!

When we last left our heroes, they were finishing up a long day (September 13) of laboratory and field work in Chinju (Jinju) University and Bito Island, respectively. September 14 would also prove to be an exciting field- and museum- day, full of bird tracks! Don't worry: I won't forget the non-avian dinosaur and pterosaur tracks!

Once again I'm forced to break our day into the field component and the museum component because there is just so much to talk about. This week's September 14 post will cover our field activities, and the next post will cover the spectacular Gajin Track Site.

We start off our day with a 7:30am wake-up and met Sujin for breakfast at a local Starbucks around 8:30am. After breakfast, we met Dr. Kim Kyung-soo at the hotel and drove to one of the in-progress construction sites of Jinju Innovation City. Remember in my last post, when I said that one of the similarities between studying tracks in British Columbia and South Korea is that many discoveries were (and continue to be) made as a result of industrial activity? Jinju Innovation City is a perfect example of industry significantly contributing to paleontology discoveries.

Excavations are uncovering track surface after track surface, and with a mandate to preserve national heritage, paleontologists in South Korea have to not only archive these large track-bearing blocks, but they also have to collect them! In the spirit of "necessity is the mother of invention," Dr. Kim designed a novel method for removing and transporting track blocks weighing several hundred kilograms...in one piece. Oh yes: and every picture in which you see a "KS" label on a track specimen? That specimen was collected and documented by Dr. Kim Kyung-soo.

People with visible faces: Drs. Kim Kyung-soo (left), Martin Lockley (center) and Richard McCrea (right) examining one of Dr. Kim's amazing track cradles for a large specimen ready to be removed to collections.

When we have the resources, we are going to bring Dr. Kim and his team over to visit track sites in British Columbia: I would love to see his track slab cradle technique in action!

Not all of the track-bearing surfaces are removed. One of the great approaches we witnessed in South Korea (take note, North America) is that people recognize - and act on - the value of preserving track localities as interpretive sites to educate the public. At this one construction site, two interpretive buildings are under construction for small interpretive centers.

I am just going to add an editorial note: this is the Republic of Korea. The country has a population of in a land area of 51,446,201 (with a density of 507 people per square kilometer) in a 100,210 square kilometers. Land, and space on which to develop, is valuable, and yet the Republic of Korea STILL finds ways to preserve and showcase their fossil heritage with respect. Now look to Canada. We have a population of 35,151,728 people spread over 9,984,670 square kilometers (population density of 3.92 people per square kilometer, albeit concentrated near the border with the United States.) So how come there is so much reticence towards protective buildings such as this one installed over important fossil sites? Take your time.

The track surface is covered to protect it during construction, so we pulled back the layers of tarps and thick felt-like cushioning to visit the surface.

Vertebrate ichnologists LOVE seeing surfaces like this...these are great surfaces for tracks!

We swept off portions of the track site to reveal some tracks with exquisite detail. The track type that has fascinated me (let's be honest: they all fascinate me) are trackways of pterosaurs. Yup: tracks of flying reptiles! When they weren't soaring through the air, pterosaurs walked on surfaces as quadrupeds, leaving wing finger impressions! HOW COOL IS THAT?!?

A pterosaur handprint! Guess what the loooong digit impression is from? (Psst: it's the wing digit!)

Editorial Note: You may want to Google pterosaurs. I don't blame you: they are fascinating archosaurs! However, you may encounter two websites in your search. One is called "ReptileEvolution.com" and the other is called "Pterosaur Heresies," both of which are run by the same person. Both of these sites are full of interesting artwork, but the information they provide on "radical" new ideas about pterosaurs is not supported by information from the fossils. Neither site should be a go-to site for accurate, data-supported information. Read the Tetrapod Zoology blog post on the issue.

One part of Dr. Richard McCrea's work is to refine photogrammetry techniques, particularly with small, low-relief tracks. This little pterosaur handprint is a perfect test subject!

Dr. Richard McCrea takes photogrammetry images for creating a 3D digital model of small tracks.

With a surface that preserved detail like pterosaur tracks, I was very hopeful for bird tracks. I was not disappointed! We didn't have a lot of time at the site, so this is the only definite track I could see, but where there's one, there's likely more!

This isn't the best picture (the room was under construction and unlit) but it is very birdie!

We drove to Sangcheong-gun (Sangcheong County) to check out a track site that was relatively close to the highway. It was a HOT day: the track surface was almost burning hot. It was a great contrast to the raindrop impressions we saw.

Oh yes, that's a bird track in the center of all of those rain drop casts.

This was a lovely track surface for fine details. The bird tracks were exquisite. The bird track in the center of the image above has slight digital pads and a lovely hint of a webbing impression!

You know you have a nice track surface when fine soft tissue details, like skin impressions and webbing impressions, are visible!

There's a lot we can tell about this trackmaker by looking at its footprint. One, this is a small bird (footprint length about 2.5 cm). Two, it doesn't have a well-impressed hallux (or reversed toe), so we know it didn't look or behave like a small crane or egret. Three, this bird only has a little bit of webbing between the middle and outer digit: this isn't a webbed bird like a duck. Four, this bird meandered, stopped, and started again, all over the track surface. This bird, if we were to take a time machine back to the Early Cretaceous, would have looked and behaved a lot like one of our present-day sandpipers. This was another track site exposed by industrial activity (construction of a highway), although our time machine shows us a peaceful scene of a very quiet, silty bank next to a small lake or slow-moving stream.

Also, we would have had to watch out for being stepped on by sauropods! Another thing we know from the tracks is that the sauropod came through first, and then the birds walked on the surface. We know this because the bird trackway actually walks around the sauropod track! How cool is that?

We then drove to a small cafe where we would eat what would be my favorite meal in Korea: naengmyeon, cold noodle soup! (Note: this is only one of many recipes I found online.) Most of the soups we tried in Korea had two versions, a regular version and a spicy version (I went spicy!) This is now a soup I make regularly for dinner, or at least the closest version I can make living in a remote area with limited shopping options.

Stay tuned for our visit to the Gajin-ri track!

Calling All Shorebirds!

Hello Dear Readers!

We have returned from the Canadian Society of Vertebrate Palaeontology 2017 conference in Dinosaur Provincial Park, and it was a blast! It was great to catch up with our friends and colleagues, and also great to see all of the ground-breaking research being done by early career paleontologists.

There's a lot happening in the next month for me. Tomorrow I grade for my next level in karate - this will be the first exam I've had since my candidacy! On June 3 I'll be leading the annual birding hike to Bullmoose Marshes, hosted by the Wolverine Nordic and Mountain Society. June 9 - 11 I am involved with hosting the British Columbia Field Ornithologists meeting, and am giving the afternoon keynote presentation...on Cretaceous birding, of course! I am also working with colleagues to finalize plans for a track site visit - stay tuned!

One aspect of my upcoming summer that is not busy is my field work life. With this year's field budget of a whopping $0.00 (don't spend it all in one place!) we do not have any large field excursions scheduled. That doesn't mean that we don't have plans were funding to materialize. Here's a list of the palaeontology projects we could  be working on this summer:

1. We still have at least four years of work to do on the Six Peaks Dinosaur Track Site near Hudson's Hope, British Columbia. Here's a video showcasing the site,



2. A hadrosaur bonebed (duck-billed dinosaurs), the first dinosaur bonebed for British Columbia. This site was featured in "Dino Hunt Canada," with an airlift of the articulated skeleton of one of the hadrosaurs. We've done as much digging as we can by hand. Watch the video!



3. Uncovering more of the world's first tyrannosaur trackways (described in our paper in PLoS One,) mentioned in this post on field work fails, and in this post on injuries in theropod tracks, and

4. A potential new dinosaur excavation site that needs several test pits dug to determine the extent of the bone-bearing section.

What this summer does is give me an opportunity to spend more time at my neoichnology (modern track) sites. My first step was to see what shorebirds have arrived in the area, so I went out yesterday to spot check my usual sites.

My first trip was to Bullmoose Marshes, about 30 km away from the Research Centre. This site is in important stop-over and summer breeding ground for a fantastic variety of birds. It was a gorgeous day to be outside.

Me, squinting into the sun, which gives me a pensive look. No one can look pensive at this marsh.

While I did hear and see a great variety of birds, including two Trumpeter Swans, I only saw one shorebird: a Solitary Sandpiper.

My submission for Worst Bird Pic. There's a Solitary Sandpiper in here!

Of course, visiting sites always provides reminders of Why We Can't Have Nice Things. These boardwalks were put in by volunteers who had to raise funds for the materials. But I guess that all pales in comparison to twue wuv.

Yes, we're all very impressed that your love for C.C. is so great that vandalism is your answer.

The water levels are very high at the marshes right now, so there was no exposed ground to check for shorebird footprints. In addition to the Solitary Sandpiper, Spotted Sandpiper and Greater Yellowlegs also frequent this marsh, but perhaps they have not yet set up their breeding territories.

My next stop was to the local dump. I often find myself going to to the dump for bird-related activities. The sewage treatment ponds are full of breeding Canada Goose, and several species of ducks and swallows can also be found. I discovered in 2016, while I was dropping off my recycling, that Killdeer also frequent one of the cleared off, rocky areas.

The dump did not disappoint! Here's a trackway of a Killdeer!

Killdeer trackway. 10 cm from outer dot to outer dot.

This made me a very happy ichnologist! These tracks were made that morning. If they were any more fresh, the Killdeer would still be standing in them.

I also saw some tracks that were made a day to a few days before, meaning that the Killdeer were not just making a one-time stop at the site. I'm hoping this means that they are getting ready to establish their breeding territory, and that I haven't missed all of the fun of them doing their nest scrape displays!

A not-so-fresh Killdeer trackway at the same site. Notice the edges are less clear than the above trackway.

Over the next few days I'll be paying this site early morning visits to see how active these Killdeer are, and where they feel is a good spot to build a nest.

Stay tuned!

Theropods or Tender-pods? The Softer Side of the "Terrible Lizard."

Nature, red in tooth and claw...

It's the common image associated with theropod dinosaurs: they are either chasing something down to eat it, or they are eating it. Every lazy bit of sad science storytelling depicts theropods consumed with one objective: devouring poor innocent plant-eating prey. From Lex asking "Where's the goat?" in Jurassic Park to Littlefoot's mom being killed by Sharptooth, theropods (and all carnivores, really) get painted with the "evil" brush and brushed off as mindless killers.

It's still too soon for me to post Littlefoot's mom's death.

Logically we know that theropods were more than just heartless (our words and judgement) killing machines. Theropod dinosaurs were and still are animals with a complex suite of behaviors that we would anthropomorphize as "tender" and "gentle."

We know that theropods built nests and incubated their young: research by Tanaka et al. (2015) demonstrated the different nesting strategies that dinosaurs used based on egg shell porosity. Egg shell is not solid: it is full of tiny pores that allow for moisture and gas exchange to happen between the egg and its environment. Based on modern nesting crocodiles and birds, the more porous eggshell is, the more likely it was that the eggs would be completely buried in a nest mound. Less porous eggs would only be partially buried with the upper surfaces of the eggs exposed. Maniraptoran theropods (dromaeosaurs, oviraptors, troodons, and our modern birds) have low porosity eggs, which would be partially exposed in the nest.

Maniraptoran theropods are well-known for another tender-loving trait: incubating eggs. Several fossil nests have been recovered with a maniraptoran caught in the act of brooding. The spectacular specimen of Citipati, an oviraptorosaur, on top of a nest of eggs is on display at the American Museum of Natural History. This is a good example of parental care in theropods.

We know that theropods (at least the maniraptorans) engage(d) in nest building and egg brooding behavior...but what about the pre-nesting activities, like courtship? Our modern theropods are famous for their courtship behaviors. Check out the mating dance of the Flame Bowerbird...



...and now imagine Oviraptor doing this dance.

"Hold up! There should be evidence of male theropods having some skeletal differences that can be used to support possible mating dances, right? Right!?!"

Using the skeleton alone, the best way to tell if a theropod skeleton was male or female is to look for a structure called medullary bone: it's a special deposit in the hollow portion of theropod bones that acts as a calcium reserve for adding shells to eggs. Medullary bone is only going to occur in egg-laying (female) theropods. However, medullary bone is an internal structure: you can't tell by looking at the exterior of a bone whether it contains medullary bone.

While there have been a few - quite a few - papers published that purportedly contain evidence of skeletal sexual dimorphism (anatomical differences in the skeleton) in dinosaurs (the most recent one uses a small sample size of tails of oviraptorosaurs) the numbers simply do not support that the differences seen are the result of sexual differences, as opposed to good ol' natural variation. An excellent study by Dr. Jordan Mallon was recently published that rigorously tests the statistics of all of the proposed cases of sexual dimorphism that involve visual differences in bones...and no evidence of sexual dimorphism was found in any of the cases. Internal eggs, embryos, and medullary bone are still the only way to confidently identify the sex of a dinosaur.

So, are there any fossils that possibly support courtship activities in theropods? We may have fossils in the form of trace fossils...ichnology to the rescue! In 2016 we published on these enigmatic traces from the Early Cretaceous of Colorado. They are paired scrape marks made by the feet of large theropods (likely an allosaur.) No tracks led up to any of the scrape marks, showing us that the theropods dug down through the layer they were walking on.

Figure 1 from Lockley et al. (2016) showing the scrape marks.

Figure 3 from Lockley et al. (2016).

These marks were a puzzle at first. We initially thought that the trackmakers were digging for water, but the geology of the area showed that water was active and abundant. Next we considered that they were digging for food, but the sandy layer the theropods were digging down to was devoid of traces of most burrowing animals. Next we considered nest bowls and/or dust bathing. Both activities, like rooting around for food, tend to wipe out the marks made by digging (based on what we've seen with dust bowls made by Spruce and Ruffed grouse in our area.)

Ruffed Grouse dust bathing, Jose Schell.

Then we considered territory marks. The closest modern example we could find of a convincing territory mark came from mountain lions. Check out this blog for some excellent pictures of the paired scrapes left by mountain lions.

This led us to consider the different reasons a theropod would make a visible territory mark...and then we came across the nest scrape ceremony.

Check out this video of the Piping Plover nest scrape ceremony (and because I love plovers, check out the Great Lakes Piping Plover Recovery Project.)


Also see this video of a Killdeer nest scrape ceremony. I know where Killdeer were nesting locally last year, so I'm hoping to get some of my own footage this spring.


To start the nest scrape ceremony, the male will define and defend their territory. They vocalize to nearby females, and demonstrate to them how good they are at digging out nests. A male may perform and create several nest scrapes during the pre-mating ceremony. If the female is satisfied with his performance, she allows the male to mate. One of the nest scrapes becomes the nest bowl.

There is a good chance that our large theropods were engaging in a courtship ceremony that involved scraping at the ground. It is not uncommon to have multiple males displaying in one location: game birds are a great example with their display arenas or leks, like the Greater Prairie Chicken.




Of course, we had to come up with an Early Cretaceous version of a theropod lek...

Figure 6 of Lockley et al. (2016). Yes, those theropods in the background are doing exactly what you think they are doing.

Recently a paper by Carr et al. (2017) published on the facial scales of the tyrannosaurid Daspletosaurus horneri (a new species) that has skeletal evidence of not just scales on its face, but very sensitive facial scales. How sensitive? These scales were likely more sensitive to touch than human fingertips. Why would a tyrannosaur have such a sensitive snout? I'll let the authors speak to that:

"ISOs [integumentary sensory organs] would have aided adult tyrannosaurids in harmlessly picking up eggs and nestlings and, in courtship, tyrannosaurids might have rubbed their sensitive faces together as a vital part of pre-copulatory play." (Carr et al., 2017)

We now have more than enough evidence to abandon the tired cliche of the one-dimensional killing machine image of theropod dinosaurs. Extinct theropods were just as multifaceted and complex as any of our modern theropods or animals that we see today. A carnivorous animal is not simply a vicious slaughterhouse on legs and wings: they attract mates and care for the young that they produce. The fact that they eat meat to support these tender activities should be free of judgement on our part. We should learn to appreciate all aspects of a carnivore's life and pass that appreciation on to the next generations.

While you are here, I highly recommend peeking into the tender lives of our modern theropods by watching live nest cams! Here are links to the nest cam I frequent. Most are nest cams of birds of prey, so you will see prey either in the nest or being brought to the nest.

Barred Owl: http://cams.allaboutbirds.org/channel/43/Barred_Owls/

Savannah Osprey: http://cams.allaboutbirds.org/channel/54/Savannah_Ospreys/

Laysan Albatross: http://cams.allaboutbirds.org/channel/41/Laysan_Albatross/

Peregrine Falcon: http://explore.org/live-cams/player/peregrine-falcon-cam

Bald Eagle: http://explore.org/live-cams/player/decorah-eagles-north-nest

Great Blue Heron: http://explore.org/live-cams/player/great-blue-herons-chesapeake-conservancy

Hummingbirds (there are babies in the nest right now!) http://explore.org/live-cams/player/rosie-hummingbird-nest

Enjoy!

References

Carr TD, Varricchio DJ, Sedlmayer JC, Roberts EM, Moore JR (2017) A new tyrannosaur with evidence for anagenesis and crocodile-like facial sensory system. Scientific Reports 7, Article number: 44942 (2017) doi:10.1038/srep44942

Lockley MG*, McCrea RT, Buckley LG, Lim JD, Matthews NA, Breithaupt BH, Houck KJ, Gierlinski GD, Surmik D, Kim KS, Xing L, Kong D-Y, Cart K, Martin J, Hadden G. 2016. Theropod courtship: large scale physical evidence of display arenas and avian-like scrape ceremony behavior by Cretaceous dinosaurs. Scientific Reports 6:1–10

Mallon JC. 2017. Recognizing sexual dimorphism in the fossil record: lessons from nonavian dinosaurs. Paleobiology, doi: 10.1017/pab.2016.51

Persons SW IV, Funston GF, Currie PJ, Norell MA (2015) A possible instance of sexual dimorphism in the tails of two oviraptorid dinosaurs. Scientific Reports 5, Article number: 9472 (2015) doi:10.1038/srep09472

Tanaka K, Zelenitsky DK, Therrien F (2015) Eggshell Porosity Provides Insight on Evolution of Nesting in Dinosaurs. PLoS ONE 10(11): e0142829. doi:10.1371/journal.pone.0142829

Field Work Fail: For Want of a Flashlight

Hello Dear Readers!

The Strange Woman has been very busy as of late: collecting additional data for a paper that is the second to last paper to come out of my doctoral thesis. These last two papers are the result of the data at the end of my analyses showing me something cool that I had no time to expand on for the thesis. Sometimes research does that to you: sometimes discoveries have their own schedule. I'm also doing other things that I'll hopefully be able to write about in the future. Right now I'm in finger-cross mode with those things.

This is to say that I am still not ready to post the results of our summer's work at the Six Peaks Dinosaur Track Site. What I can do is show you a video we had done on the site. Here is a teaser for you!



I will share a dinosaur track field work story with you. This one dates back to 2011, and tells the tale of how we spent the night in a pile of leaves at the end of October in northeastern British Columbia.

***

The best laid plans of rodents and researchers...

Fieldwork in the Peace Region of British Columbia is not simple under the best of conditions, with the best conditions being fair weather in mid-summer. There are practical reasons for this. Materials don’t set well in cold or wet conditions. The ground is either too wet (for the spring) or too frozen (for the fall and winter) to safely remove fossils. Many times the weather renders the conditions too dangerous for field crews. This is why the paleontology research field season is short in the North. The PRPRC’s typical field season runs from June-September. If the snow and sub-freezing temperatures permit it, we’ll do short excursions well into the first half of October. It’s an exceptional discovery that will bring us into the field in end October or early November.

This is the story of one such exceptional discovery.

The site was discovered by a regional guide-outfitter, Aaron Fredlund, in 2011. He had come across a small exposure of grey sandstone sticking out from under a hill of Ice Age silt, mud, and boulders. Being an experienced tracker of modern animals, it didn’t take Mr. Fredlund long to notice the large, three-toed footprint and identify it as the track of a large meat-eating dinosaur. It also didn’t take him long to reason that, if he cleared some of the debris off of the rock in front of the footprint, a second footprint could be uncovered. He was correct. The two images were immediately reported to me, Dr. Richard McCrea, and Dr. Charles Helm. A combination of the track type (large theropod) and the age of the rocks (Late Cretaceous, approximately 72 million years old) led us to identify these footprints as those of tyrannosaurs!

Tyrannosaur footprints were not unknown to science: “singleton” footprints have been reported from the Late Cretaceous (Campanian - Maastrichtian) deposits from the US, Canada, and Mongolia. However, what palaeontologists were missing was a trackway: a series of footprints made by one animal. Isolated footprints are like finding an isolated dinosaur bone, while trackways are like finding a complete skeleton. A trackway of a tyrannosaur would provide a tonne (pun completely intended) of information on how this tyrannosaur moved when it was alive. Tyrannosaurs are the best-known dinosaur predator, but their footprints were the least well-known. This site had the potential to change all that.

At the time of reporting, both Rich and I were out of town. Charles made a visit to the site with Mr. Fredlund in our absence so he could report site conditions and access. There was no GPS data taken during the visit (one of those frustrating “I can take you right to the site” situations), Charles reported from the site visit that the locality was both treacherous and tricky to access, and would require an ATV to haul in the research equipment safely. In short, we would need a guide.

Fast forward to October 23, 2011. Charles had a break in his busy schedule to visit the site with us. This was our only opportunity to get the site documented and replicated before the end of 2011. We were starting to head into winter: there was no snow yet, but the daytime temperatures were not above 10°C, and the nighttime temperatures were hovering around and just below 0°C. We could not physically remove the trackway, so we had to make a silicone mould (or peel) that would be used to make an exact replica that could be housed (and studied) inside during the winter. As difficult as fieldwork is, cold exacerbates all difficulties. Since silicone doesn’t set up in cold settings, we had to both mould the trackway and heat the silicone so that it would cure properly. This was a large trackway: the two exposed footprints covered a distance of over 2 meters long, and almost a meter wide. We would need A LOT of silicone. Silicone is an expensive molding material, but this site was worth it.

We spent that week gathering silicone, mixing buckets, brooms, brushes, documenting equipment, and all of the gear we would need to keep the silicone peel warm enough to set: tarps, propane tanks and heaters. Me, Rich, and our field technician Tammy Pigeon had all of the field gear ready to go and loaded into the ATV on Friday. We were scheduled to leave Sunday, so we thought we had a full day (Saturday, October 23) to gather our personal field gear, which had been all packed away for the winter.

We got a call early Saturday morning. Charles’ schedule had changed: could we possibly head to the site that morning? We scrambled to throw together our personal field gear. An hour later we were ready to go...or, at least, we thought we were ready.

Cue ominous music.

We followed Charles out to the “trail head”: a labyrinthine series of decommissioned logging roads long overgrown with dense brush. We scouted the best path for the gear-laden ATV among the bogs, pits, and tumbles of burnt log piles. After a long while we reached the top of the hill: at the bottom of the steep slope was the humble little rock exposure containing the tracks of one of the most famous and charismatic predators ever known.

NOTE: there will be very few pictures of the trail down to the site and of the overall site. This site is still vulnerable to vandalism and general people nastiness that all of our publicly accessible sites have experienced. The selfish actions of a few do ruin things for the many.

Once we uncovered the camouflaging coating of rubble from the track surface, Tammy and I set to readying the track surface for the silicone mould. We were expecting to have to do a bit of digging, brushing, and wiping. What we were not expecting was to have to clean a 30 cm layer of kaolinite (clay) out from the all of the nooks and crannies of the footprints. This clay was stubborn: it required several washes and (soft) scrubbings before all of the clay was removed from the footprints. Removing the clay coating from the surface revealed small skin impressions that we would have never seen (or moulded) had the footprints remained “dirty”.

As frustrating as the clay was to clean out of the skin impressions, it was very exciting to see: this type of clay forms from volcanic ash falling onto the footprints soon after they were made. This told us that the weather patterns were right for a volcanic ash layer to fall on northeastern British Columbia 72 - 74 million years ago. Perhaps our tyrannosaur actually saw the glow of the eruption? We’ll never know, but it is fun to imagine.

The track surface cleaning took a long time. In the meantime, Charles and Rich moved the research and moulding equipment to the site by easing the AVT down the hill. What goes down was not going back up: the hill was too steep for the ATV to make a return trip using that route, but we had planned for this: an alternate route was mapped out using Google Earth for our regress. Rich calculated where the third footprint in the series would be if it were preserved. If you know approximately how long of a step the trackmaker was taking, which we had from Footprint #1 and Footprint #2, you can figure out where Footprint #3 would be, even if it is still covered in rubble. Charles and Rich began excavating at the base of the hill to search for the third footprint, and successfully uncovered it!

The first tyrannosaur trackway. a) The second footprint in the trackway. b) The exposed trackway. You can see, way at the end of the trackway, the pale clay layer that we had to clean out of the footprints. Modified from Figure 2 of McCrea et al. (2014).

While Tammy and I began the detail cleaning of Footprint #3, Rich got to work documenting the exposed trackway. This is when he noticed something odd about this trackway. The Footprint #1 made by the left foot, was a little damaged by weathering. The inner toe (digit II) was not completely preserved: it seemed too short. Footprint #2, from the tyrannosaur’s right foot, was uncovered by Mr. Fredlund, and all of the toes were beautifully preserved. When we finished cleaning out Footprint #3, made again by the left foot of the tyrannosaur, we saw that digit II was too short on this footprint. This was not damage due to weathering: this animal was missing the end of its inner toe! This is called a pathological footprint: check out McCrea et al. (2015) for a detailed description of injuries seen in dinosaur footprints.

Figure 7 of McCrea et al. (2014), photogrammetric rendering of the first tyrannosaur trackway. You can see the consistently missing digit II impression. I might call this specimen "Stumpy".

Charles had to leave the site around 3pm. That was when we were finally ready to start the silicone mould. Silicone is easy to mix by hand in small quantities at room temperature. However, I had to mix large batches at around 5C. Silicone is very, very stiff when it’s cold: it’s like trying to stir molasses or all-natural peanut butter that has been sitting in the fridge. Silicone also doesn’t set properly if the catalyst and reagent aren’t thoroughly mixed: it just stays a gloopy, slimy mess.

There is another drawback to late year fieldwork: the lack of daylight. The light and temperature started to drop as I stirred, and stirred, and stirred. Each batch took about half an hour to properly mix, and then another half an hour to pour. By the time we had mixed and poured four batches of silicone, and had set up the heating tent over the silicone peel, it was 6:30pm and dark. Ice had started to form on standing pools of water. Our breath frosted in the air. It was going to be a cold, clear evening.

This is when we discovered just how rushed we were when packing our personal field gear. We had food, guide tarps, GPS, satellite phone, and warm(ish) clothing, but we had forgotten one crucial piece: The Flashlight. We weren’t initially concerned: Rich had mapped out a seismic cut line that we could use with the ATV (which has headlights) to get back to the field vehicle. It was a slow, bone-jarring trip through the dark wilderness, but we reached the opening to the cutline. We were home free...

...or not. Between Google Maps taking the images of this route and our escape (about two years), a beaver had made a dam, turning what would have been a steep but manageable slope into a large pond abutting a steep grade. There was no way to drive around the pond. After expressing a few non-printable words towards beavers and all of their kin, and finding out that similar access points were also cut off, we made our slow creeping way back to the track site.

Bwaahaahaa! Image link.

We returned to the site around 11:30pm. After checking that the heating system for the silicone peel was still working, we surveyed our possible lighting resources. GPS screens emit light, but not enough light to hike through the woods. Makeshift torches of burlap do not work unless you can soak the ends in pitch. We had gasoline, but that burned too quickly for a consistent light source. None of the screens on our 2011 flip phones gave enough light to safely hike by (this was before phones with flashlight apps). The Moon was not full enough to hike by, and our trail was treacherous even in full daylight. We had no choice: we were stuck for the night at the track site.

I called Charles on the satellite phone to let him know our situation. The phone made an unstable connection, and all I could get out was “Hi Charles, we’re OK, but stuck at the site for the night...” when the connection broke. Satellite phones are great for remote field work, but at that particular time our satellite coverage was poor, and we were in a canyon. What I had wanted to tell Charles was that we were stuck for the night, but could wait until dawn to make our way back to the truck.

We assessed our emergency camping options. We set up our first camp on an open patch of ground, with our backs to the ATV and facing a nice fire. We used our backpacks in place of a ground pad, and huddled under the guide tarp. We were fine here until the winds shifted direction. The ground cooled and sucked the warmth right out of us. We then moved our makeshift camp into the shelter of the woods. While Rich cleared a safe area for a fire, Tammy and I built a huge pile of dried leaves. Once the fire was going we burrowed into the leaf pile and pulled the guide tarp over us.

I actually fell asleep. I can sleep in just about any situation, and after the long day and finally being warm and comfortable, I slept like one of the rotten logs on the ground next to us. All of a sudden my lovely sleep was interrupted by loud crashing down the hill and shouting. It was an unexpected rescue party! When I had called Charles, he interpreted the call as a “please come rescue us” call. After letting people in town know we were safe, he, Thomas Clarke, and Pearl the Helm Dog hiked along that horrendous trail in the dead of night to bring us home. They reached our campsite around 3:30am.

My first emotion? I will admit that it was annoyance at having been woken up (this will be the first time Charles will hear this confession). I was prepared to sleep for another couple of hours. Part of my brain wanted me to grumble “Go away!” I was the only one thinking that: Tammy admitted to feeling quite chilled and uncomfortable. We extinguished our fire, packed up our gear, and followed the lights of our rescuers back to the truck.

There, sitting on the front seat to add insult to injury, was a flashlight that had fallen out of one of our backpacks.

Every field bag and field jacket that I own now sports this teeny little flashlight. Lesson learned.

This trackway was well worth the unexpected overnight camping trip. Later visits to the site in 2012 and 2013 gave us time to clear off more of the track surface, revealing two more tyrannosaur trackways. All three trackways were walking at a leisurely pace (between 6.4 and 8.5 km/h) in the same direction and were spaced evenly apart (about 3 m). We were also able to figure out approximately how old the track-makers’ were when they made their journey from present-day British Columbia to Alberta: the track-makers were between 25 and 29 years old. This may sound young to us, but this is close to the upper age range known for Albertosaurus sarcophagus (Erikson et al. 2010). 

Figure 3 of McCrea et al. (2014). I'm working on cleaning out one of three trackways, and cursing at clay.

This site told us several things: 1) that tyrannosaurs spent time in northeastern British Columbia, 2) how tyrannosaurs walked and moved their feet when they walked, and 3) that adult tyrannosaurs, despite evidence of antagonistic behavior (e.g. fighting and face-biting, Tanke and Currie 1998) did spend time in each other’s company. This track site is also good evidence of group behavior in tyrannosaurs. There were hints before of tyrannosaur group behavior. Currie and Eberth (2010) suggested this from the tyrannosaur bonebed in Alberta, but bodies and bones can be moved after the animals die and deposited in a pile: in situ footprints cannot.

This site has great potential for further excavation: all three tyrannosaur trackways head into the hill. Unfortunately that hill is very high and steep, so any future work will require a lot of resources to move the mountainous amount of silt, sandstone, and mud from over the track surface. We cannot safely tunnel into the hill to expose more tracks: that seems like a plan riddled with Wile E. Coyote kinds of danger. 

Hopefully this tale of working on the terror of tyrannosaurs - and a fairly epic field work fail - will amuse and entertain until I can get to the Early Cretaceous track site work we did this summer. Stay tuned!

References:

Currie PJ, Eberth DA (2010) On gregarious behavior in Albertosaurus. Can J Earth Sci 47: 1277–1289. doi: 10.1139/e10-072  

Erickson GM, Currie PJ, Inouye BD, Winn AA (2010) A revised life table and survivorship curve for Albertosaurus sarcophagus based on the Dry Island mass death assemblage. Can J Earth Sci 47: 1269–1275. doi: 10.1139/e10-051 

THIS POST: McCrea RT, Buckley LG, Farlow JO, Lockley MG, Currie PJ, Matthews NA, et al. (2014) A ‘Terror of Tyrannosaurs’: The First Trackways of Tyrannosaurids and Evidence of Gregariousness and Pathology in Tyrannosauridae. PLoS ONE 9(7): e103613. doi:10.1371/journal.pone.0103613

McCrea RT, Tanke DH, Buckley LG, Lockley MG, Farlow JO, Xing L, Matthews NA, Helm CW, Pemberton SG (2015) Vertebrate ichnopathology: pathologies inferred from dinosaur tracks and trackways from the Mesozoic. Ichnos 22(3-4):235-260.

Tanke DH, Currie PH (1998) Head-biting behavior in theropod dinosaurs: paleopathological evidence. Gaia 15: 167–184.