Tracking dinosaurs here and there

Tracking dinosaurs in Istria

At the Jurassic coast

More on Pula ankylosaurs

I have discovered the second site containing ankylosaur tracks (dinoturbation) near Pula about a year after the first one, which is about a kilometre away. It is interesting, but this time I thought I was looking at the single theropod footprint. Yet, it didn't seem right. It didn't look like a typical theropod footprint. Nearby was the second impression, only convex (infilling). The pace angle was too wide for a theropod. I have also noticed there were in fact 5 toe impressions. The print was obviously left by a quadrupedal animal: a large ankylosaur. Later, I have discovered more foot impressions of the same animal, or the animal of the same size.

The red outline of the best preserved impressions in the ankylosaur trackway.

Another foot impression ( right hind foot - pes) of the large Sauropelta-like dinosaur on the same outcrop. This one is not part of the trackway above (red outline is my interpretation).

Click to enlarge.

Some Istrian tracks and fossils

This is a piece of a Cretaceous rudist reef I have found on the dry wall somewhere near Banjole in southern Istria. There were even larger pieces of these extinct mollusks. Some big ones reminded me of the elephant tusks. They were to big for me to take them with me.

 In the photograph below is another strange track from one of Pula's beaches. I am not what is it exactly. Was it a small theropod track or a sea bird footprint? It even seems to have been left by a webbed foot.

Observe the possible resemblance with the recent sea gull tracks in the cement.

A theropod track from Solaris outcrop

"The field work in the late Albian track site of the Solaris Campground near Cervera/Červar (Torre/Tar municipality, Istria, Croatia) was undertaken during the years 1995-96 thanks to a grant of The Dinosaur Society and the collaboration of the local authorities. The field work at the site has been described in DALLA VECCHIA (1996). A description of the site before the cleaning of the main footprint-bearing surface and its detailed mapping and description can be seen in DALLA VECCHIA (1994). The detailed description has been published by DALLA VECCHIA et al. (2000)."
What's interesting about the Solaris track sites is that they are represented with relatively small dinosaur tracks. Dalla Vecchia speculates that the dinosaurs were of a diminutive size due to their habitat. They lived isolated on an island, whose resources couldn't provide for the "full-size" large dinosaurs that inhabited the mainlands. On the other hand, although roughly from the same age and just some 40-50km away, dinosaur tracks from Pula beaches are of many size classes, the biggest of which are among the world record breakers.

In the image below, you can see one of small theropod tracks from the Solaris beach. Red outline is my interpretation. This one wasn't described in any paper, yet.

There is probably more than one footprint in this image, but I have outlined only the best one.

An ankylosaur trackway destroyed in Pula

I have just returned from a trip to Pula. It is sad, but a few of my photographs is the only thing that has remained of the first ankylosaur trackway in Pula, Croatia (the Adriatic-Dinaridic carbonate platform). I had discovered the tracks in 2011 and I didn't even manage to write the paper. The trackway, which was situated at one of the most frequented beaches in Pula has been covered with a thick layer of concrete for sunbathing. There are more tracks on that particular beach, but just one trackway that runs parallel to this one was preserved enough for research to be conducted. I fear that one is going to be destroyed as well in order to make the beach more comfortable for the numerous tourists. A few years ago I tried to warn the government institution State Institute for Nature Protection about the valuable, numerous trace fossils that are in the danger of being damaged or destroyed, but in vain. This isn't the first case of this kind either. Recently, the theropod trackways have been destroyed and damaged out of ignorance and negligence in Lovrecica, Istria, Croatia. News coverage of that event. That Lovrecica tracksite was even described in a scientific paper and should have been protected.
It is ironic, but I am probably the only person aware of this latest loss.
The "fossil of the fossil"- my photograph of irreversibly lost valuable piece of palaeontological natural heritage in Pula:

Latest news (August 2014): good ones (for now)!
Recently, I've visited this site and discovered that the concrete missed these two tracks (in the photo above) for about a meter. They are still there, but were covered with a muddy water. That's why I didn't see them during my previous visit.

A quiz question: Who left this track?(2)

Guess the tetrapod from the track!
 ... and the answer is: a large iguanodontoid
 

 In the image above:
1) Iguanodontian track from the Main Brijun island. Probably left pes footprint. Note my feet size #46 at the bottom of the photograph.
2) A close up of the hoof (ungual) #3. Note the similarities of the print (cast) with the Romanian true ungual fossils (Fig.4). Note that the base, or the distal part of the ungual also left an impression. In fact, I have discovered that a rather well defined toe impression of an iguanodontoid track maker often preserves and thus could be considered a diagnostic feature.
3) My interpretation of the footprint - red outline.
4) Iguanodontian ungual #3 from Romania, Early Cretaceous (left-bottom; right-top of the hoof), from this paper:

 IGUANODONTIAN DINOSAURS FROM THE
LOWER CRETACEOUS BAUXITE SITE FROM ROMANIA
ERIKA POSMOŞANU
ACTA PALAEONTOLOGICA ROMANIAE V. 4 (2003), P. 431-439


As for the results of the Quiz. There's no winner. Nobody even tried guessing. So, am I just imagining things?

The iguanodontoid tracks from the Main Brijun island

You can download a free PDF of the official brochure for the dinosaur tracks of the Brijuni islands
(... in the production of which I wasn't involved): Promenade of dinosaurs .

In the photograph below is presumably one of the iguanodontoid (left pes) footprints on the peer of the Main Brijun harbour. The yellow outline is my interpretation. Track is about 32 cm long. Note the pointed toe #4 impression.

The probable, very shallow iguanodontoid tracks in my photographs are from the Pogledalo promontory of the Main Brijun island. My interpretative drawings are on the right. I have placed my interpretation in red outline from the bottom picture, over the yellow outline in the upper image for comparison. It seems there's a manus impression between the toes #3 and #4 of the right pes. Note the pointed toe #4 impression, just like in the footprint on the peer.The footprint is about 55 cm long.

The iguanodontoids and sauropods would present a perfect prey for the large theropods that left their footprints on the same promontory.

Kamenjak ornithopod

There is an upper layer on the Grakalovac (Kamenjak #1) site, that has preserved tracks, too. I wonder why nobody has checked it out, yet. Just at a superficial glance I have spotted a nice, very small ornithopod footprint - in fact a natural cast, just about 12 cm long. I took a better look and there were a couple of poorly preserved tracks that formed a small trackway of apparently slowly walking dinosaur. See my photograph and interpretation outlines.

Whether this trackway was left by a juvenile or adult animal, nobody can tell. There are also some poorly preserved theropod tracks on that rock layer near by.

A quiz question: Who left this track?

Guess the tetrapod from the track!

The Cape Pogledalo, Main Brijun island (V. Brijun) site.

  

To tell you the truth, at first, while looking at it in situ, I miss interpreted the impression in the photograph below. Only back at home when analysing the photograph on my PC, I have concluded I had been totally wrong in my attribution. It is not a typical footprint example for the particular ichno family. So, this task is really a tough one! A specific diagnostic feature made me change my initial speculation. After that I spotted the other characteristic features, that were not that obvious at the site but which confirmed my thoughts. Although, this diagnostic feature is not always present in the footprints of these dinosaurs, it helped me resolve my dilemma quite a few times.

  

I'll give you a couple of hints: The site is the Cape Pogledalo on the Main Brijun island (Istria, Croatia), of the Barremian age (early Cretaceous), described in the paper by Dalla Vecchia ; this print was not described in his paper. Note the tip of my shoe (#46) on the right for size. When watched from the side, the track looks like a large shallow bowl. By the icnology standards the footprint is poorly preserved (except one crucial detail).

I challenge the ichnologists to give the answer and the clues in the comments. What kind of animal left this print? 

 Of course, after some time I'll reveal my interpretation and the  diagnostic hot spots.

The usual suspects are: A) theropod, B) sauropod, C) stegosaur, D) ankylosaur, E) iguanodontoid, F) croc, G) pterosaur, H) turtle, I) lizard, J) bird, K) mammal, L) fish

Please, select one of the answers and post it via Comments below:

Grakalovac theropod tracks mystery (2)

Here is Fabio's (Dalla Vecchia et all, 2001) map of the Grakalovac (K1) site. In my opinion it is incomplete because the important (new?) tracks are omitted. The photograph below is turned upside down for coordinating the map's view point and the map's contents. "B" and "C" stand for the footprints and their track makers (see my diagram in the previous post). "S" stands for the undefined sauropod or/and ornithopod tracks.

In the mosaic photograph below are the tracks and the pace lengths of Grakalovac theropods arranged by size, growing from left to right. In this case, it seems the smaller the theropod, the relatively longer pace.

The next mosaic photograph are the closeups of some individual prints. "D" is mostly in-filled outline of the track. The track marked with "D" is outside the map area. "S" is apparently an oval shaped manus-pes set  of a very small sauropod. The pes has the drag marks behind it.

Although at the first sight the image in the first row below appears to be medium-sized, it is in fact just a partial print, missing a good deal of the heel. This prints is also outside the Fabio's map. In the right is the enlarged and superimposed red outline of the "C" print. It is revealing the true shape and size of this print (about 36-38 cm long).
The bottom row is the "D" print again with the interpretation on the right.

More to come in one of the posts to come: Are the peculiar tracks on Grakalovac, hadrosaur baby tracks or the prints left by a very small ornithopod ?

Grakalovac theropod tracks mystery (1)

 Kamenjak theropod lineup

When comparing my finds, photographs and measurements from Kamenjak 1 and 3 (I had discovered two more tracksites on Kamenjak, so I have named the sites K1, K2 and K3), with the data and conclusions from Fabio's (Dalla Vecchia et all, 2001) paper Dinosaur track sites in the upper Cenomanian (Late Cretaceous) of istrian peninsula (Croatia), describing the tracks from Grakalovac promontory (Kamenjak 1 or K1) something just doesn't add up. Many new questions and speculations appear. Here are some of my thoughts regarding this problem:
1. The theropod morphotype with a relatively very long  middle toe (#3) is reminiscent of an ancient theropod trait going all the way from the late Triassic and early Jurassic (Anchisauripus, Grallator, Brontozoum). Given that in general theropod feet are rather conservative and that they have not changed much over the 100 million year span, this can be plausible. I have already concluded that the tracks on Grakalovac were probably left by a ceratosaur or a compsognathid.
2. Dalla Vecchia has noticed and featured in his paper two size classes of theropod tracks on Grakalovac (K1), both being the same or very similar morphotype.  It seems that Fabio and his colleagues either didn't notice the other tracks, or more likely that the erosion has uncovered these new tracks during the past 14 years. I have noticed several new tracks, some of which were quite unusual. Among them are the ones that look like belonging to a baby hadrosaur.
3. It is a consensus that Istria and some other parts of ADCP was by the Cenomanian (Late Cretaceous) large island with the dwarf insular dinosaurs inhabiting it. That's where my large-foot theropods from K1 and especially K2 don't quite fit in. Or do they?
In the diagram below is the Kamenjak theropods lineup. The little brown silhouette is the Chinese "large compsognathid", with the foot about 11-12,5 cm long (A); marked with (B) is the small Grakalovac (K1) theropod from Fabio's paper and my photographs with a foot 16,5-17 cm long; (C) is the larger specimen from the paper (K1) and (D) is the largest track maker from K1 with the foot 38-40 cm long. The yellow silhouette (E) is the giant with the similar foot shape from the K3 track site, I had discovered last year. Its foot was around 65-67 cm long. 

3. So what is strange with this "insular" ichnocenosis is the obvious presence of very large theropods. I could settle with the 5-meters long one as one of a plausible size (D), but my discovery of the footprints which translate into a 8-10 meters huge beast (E) made me wonder: Am I seeing things? Are my interpretations wrong? Maybe the tracks were deformed? Maybe these were over sized under tracks? So far the evidence speaks in favour of true tracks.
4. Diminishing size or regression in growth of once large insular herbivores in order to compensate for the reduced food sources and maintain the viable population is a well documented biological scenario. So far, the evidence (tracks of herbivorous dinosaurs in Cenomanian rocks of Istria) speaks in favour of the pygmy island dwellers.Those were the small sauropods and small ornithopods.
How do the large theropods fit in here? Maybe they were oriented towards the sea based food? Fish eating dinosaurs? Like the spinosaurids. In any case, I do speculate that the small sauropods had to have some form of defence against the fierce giant predators. Maybe they were heavily armoured like the ankylosaurs? It is even possible that we still didn't find the tracks of the larger Cenomanian Istrian herbivorous dinosaurs.
One thing is certain: We will continue researching and learning new things about dinosaurs and their fantastic, mysterious world.

Back to Grakalovac (3)

It is a bit strange but the small theropod track morphotype fits the really ancient theropod foot bones. The one by the late Triassic Coelophysis. I speculate that these footprints were maybe left by a ceratosaurid or possibly by a compsognathid. The "large compsognathid from the early Cretaceous Yixian formation of China"  Huaxiagnathus is almost big enough to be a suspect. It's foot is only about 25% shorter than this Grakalovac (Kamenjak 1) diminutive theropod footprint. The proportions of the toes are quite similar. So our mini theropod might have been some close relative of this Chinese predatory dinosaur.

The articulated Huaxiagnathus feet in profile, from the paper.

Marvelous looking flat exposed rocks on the Grakalovac promontory. The view from a higher track baring outcrop. Some of these feature ripple marks and some of them still hide other tracks and traces.

Back to Grakalovac (2)

To continue from the previous post, here is the second footprint (right pes) of the small theropod from the Grakalovac promontory...

... and here is the pace length (photograph below, with my red outline interpretation). Indicates a rather slow walk of a long-legged theropod:

The first nudists on Solaris beach

Actually, the heading of this post is probably erroneous, because the small to mid-sized theropods were almost certainly not naked, but dressed up in their fancy "dino fuzz". However, there's no question about it that they were the first ones to occupy these wonderful beaches near Porec, around 100 million years ago (late Albian, Early Cretaceous). Fact is that the countless dinosaur tracks "litter" the long beach of the large Istrian naturist resort  Solaris.
To take these photographs without being surrounded by the naked people, I had to visit the site in December.
See one of my previous posts: "Small sauropod footprints at the beach" for more information.
In the photograph, you can see the "messy dinosaurs" again. There are numerous footprints in this image alone, in various states of preservation. I tried to outline the best ones. The largest theropod prints measure some 28-29 cm in length. So, I presume the animal was up to 4 meters long.
In the centre, there is a brown outline of what seems to be a small ornithopod. I think this print is not what it seems (see my post about the tracks on Kamenjak). In fact, this is just the mid section of the theropod track that got preserved in the "paleo-sand". Of course, the tracks were left in a fine wet sand, which is now a hard carbonate rock.

Happy International Labour Day!

Tracks, tracks...everywhere (3)

I don't know if I have been clear enough, so far. This cape Kamenjak track site is NEW and has not been described yet. Nobody has noticed nor detected these Cenomanian dinosaur tracks. I call it "Kamenjak 3".
I've been analysing my photographs from this site and the site that was described to a certain degree in Fabio's (Fabio Marco Dalla Vecchia) paper (Grakalovac promontory), which I have named "Kamenjak1" and all my finds lead to this conclusion: In Cenomanian (late Cretaceous), Istria was a part of a large piece of land (Adriatic Dinaridic Carbonate Platform - ADCP) sustaining viable populations of various types of big dinosaurs. It was either a very large island or still Afro-Arabic  peninsula. Not only that I speculate that a large tyreophoran track is present on Grakalovac (see my previous posts), but it seems quite big ankylosaur was present on this new site, too. While this is still just a possibility because the tracks are poorly preserved (one is outlined, while the other is under my foot), the  theropod footprint beside them speaks for itself. The largest one was some 73 cm long. The print is shallow, because the substrate was already quite dry when it was made, so it effected the mud cracks. The "owner" of the foot must have measured at least 9-10 meters in length! I have outlined the probable prints.

Here is the size and shape comparison of the theropod tracks from "Kamenjak 3" site (red bar is 12cm long). The largest footprint is from the photograph above.