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).
When I took this photograph back in 2009 it didn't tell me much. It just looked like it might have been some unidentified dinosaur trackway. Or not. My first suspect was a sauropod, of course. This morning I was browsing through my files looking for some photographs for the text I intended publishing and something caught my eye in this image. Some of the "footprints" actually looked like if they had toes. The toes were arranged pretty much in the order like in the ankylosaur feet (Sauropelta-like): I quickly added up the simple math and it dawned to me that this little dinoturbation is in fact the part of the large ankylosaur dinoturbation for which I thought had ended a few meters away.
In my red outline you can see my interpretation of some of the tracks. Yes, these ankylosaurs were gregarious and they congregated in three size-classes. There were also some medium-sized (maybe dromaeosaur-like) and some huge theropods around.
LM = left manus; LP = left pes; RP = right pes (click image to enlarge)