Some tracks from the Main Brijun island

The trackways outcrop at the Pogledalo promontory of the Main Brijun island. Early Cretaceous of the ADCP (Adriatic-Dinaridic carbonate platform).

Some Barremian tracks from the Main Brijun island (the Pogledalo promontory), with my interpretation attempt.

Outlined in green is apparently a left foot impression of a large iguanodontoid. Bellow it in the photograph is a right footprint of the medium-sized theropod (red outline). There has been some skidding in the mud of both animals. The iguanodontoid track is partially (toe-hooves II and IV) a positive (cast). There is a track I couldn't figure out (this time) left of the iguanodontoid footprint.

Having epiphany, but lacking camera

It was a nice long weekend in Pula. It was a bit too hot and humid but on a bright side the water was warm and pleasant for snorkeling. I had an epiphany on a rocky beach we frequented over the years. While waiting to get dry enough to take our clothes on after swimming I took a good lock at the rock we were standing on. It was full of small theropod tracks! They were poorly preserved, faint and hardly detectable, but they were there! I managed finding a couple of trackways consisting of three consecutive tracks of the same animal in each trackway. Unfortunately, I didn't bring camera with me and we were soon to take our trip back to Ljubljana.

Some nice strong current ripples. The layer has been uncovered recently, so it looks like the tide has receded and left these traces just hours ago. In fact, it was about 100 million years ago.

Why do I hate ripple marks? Because they can trick you into thinking that you have found a dinosaur track! It is tough to be certain in a case like this.

Nice old ripple marks (100 million years old!)

A poorly preserved theropod trackway (Pula). Something is strange about this footprint. It seems like it lacks toe #2 or that it is very short (?) Could it be a dromaeosaurid? The theropod tracks in Pula that could be attributed to this group of dinosaurs are extremely rare. At the time (Early Cretaceous) Istria (ADCP) was probably attached to the Afro-Arabian continent.
 

A giant saurood trackway (Pula)

A small salt pond In Pula

Above: A nice natural cast footprint of a medium-sized ankylosaur (Pula)

Living on the hedge!

This looks like a sauropod pes track... or on the second look it may be an iguanodontoid track.. I'll have to check on this one.

I can see some tracks here ... hmmm..or do I?

Small iguanodontoid tracks

Here are rather well preserved couple of small ornithopod footprints from the late Albian of Pula.

My interpretation of the tracks is the red outline in the right image. It seems there was some foot dragging and maybe even slipping over the mud.

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?

A poorly preserved ornithopod track

Here is another example of a "questionable" dinosaur track from Pula. According to my scale I would grade it as a poorly preserved track (***). It is not easy to spot on these weathered rocks, although it is a convex, or relief track. The natural cast. It is slightly darker colour and there are more similar prints there. In its overall shape it does remind of an ornithopod, iguanodontoid footprint of the Hadrosauropodus type, but due to the state of its preservation it may still be a theropod.
See the b/w outline of Hadrosauropodus langstoni  - Lockley et al. (2003) track at the bottom.
My interpretation is the red outline over the print in the second image.

Some of the Cretaceous hadrosaur tracks are well described in a paper. HADROSAUR FOOTPRINTS FROM THE UPPER CRETACEOUS FRUITLAND FORMATION, SAN JUAN BASIN, NEW MEXICO, AND THE ICHNOTAXONOMY OF LARGE ORNITHOPOD FOOTPRINTS SPENCER G. LUCAS1, ROBERT M. SULLIVAN2, STEVEN E. JASINSKI2 AND TRACY L. FORD

"A reconsideration of the ichnotaxonomy of large ornithopod footprints suggests that only two
ichnogenera may be valid: Caririchnium (= Hadrosauropodus) and Amblydactylus (= Iguanodontipus)."

Monster iguanodontoids

  

Pula, Istria, Croatia, late Albian (mid-Cretaceous)

About a 100 million years ago, the beaches near the city of Pula (which itself has about 3000 years long history) were sandy and muddy and the sea was shallow. The rudist clams formed some sort of rudist reefs not far from the coastal line. The stromatolites colonies were sticking out of the water, while the large sturgeon or/and guitar fish probed the mud for food swimming the shoals. Small, large and huge dinosaurs, crocks, monitor lizards and pterosaurs left their footprints in the wet sand and sticky mud.

  Many years later, the old beaches turned into multilayer limestone rock, looking like some sort of a giant book. The ancient archives with the notes of the the life long gone,waiting for the sea to uncover them and somebody interested and inquisitive to read the fossil "hieroglyphs".

Here are the pes footprints of the immensely large iguanodontoid. I am standing on the convex  left pes with infilling, while photographing the concave right pes (footprint) in an oblique view. My yellow outline marks the impression. The displacement rim is quite nicely visible, as well as the mud suction traces along the mid line. Each of the prints measure unbelievable 135-145 cm in length. I don't think there was a larger iguanodontoid print discovered anywhere in the world, so far. Yet, these prints are situated on one of the most popular and crowded beaches near Pula. I've stepped over these prints so many times myself over the years without noticing them. Why? Simply because they were so enormous, that they were too difficult to spot and figure out as once belonging to a living, breathing animal. The ornitischian who left them in the wet sand must have measured at least 18 to 20 meters in length! (See the comparative sizes in my banner)

Why is larger track harder to spot?

 

It is hard to believe, but people are more likely to notice the small dinosaur tracks, than the large ones. Even many professional paleontologists fall into that group. Although, it is rather ironic. Don't you think? I mean, many dinosaurs were known for their giant size. After all they were the largest terrestrial animals that ever lived. 

A few years ago, at first doubtful of my own eyes, I managed finding very large dinosaur tracks on the Istrian beach which is very busy with tourists in the Summer months.The age is Early Cretaceous, Late Albian. Before some 100 million years ago.

In the photo is a giant iguanodontoid footprint (right foot) measuring about 85-90 cm in length. This was my first find of a gigantic ornithopod track. I have never expected that I will find a couple of even much larger iguanodontoid foot impressions, in the same area, just a year later. The red outline is my interpretation of the main shape. There are several less preserved prints of the same animal around this impression. 

These are footprints from other countries for comparison:

Note the resemblance with Caririchnium sp. from the Uhangri formation (image from the Research Report on the Haenam Dinosaur Tracksite, Korea, 1998)...

...or with this footprint of Hadrosauropodus nangxiogensis (from Xing et al. 2009).

It seems, the Istrian iguanodontoid footprints show both features of an hadrosaurian track and the iguanodontian one.