Honestly, it does not really swim again at all. There are no mentions in popular documentaries. There are a few Dolichorhynchops mentions in a few varied documentaries. The main place it does show up where we can watch a model of Trinacromerum in motion is actually in the Facebook game Jurassic Park Builder. Unfortunately it is not too factual and not at all like we usually share here on movie Mondays. At least there is something though! The model is pretty accurate in terms of body shape and proportions of appendages to the body. The fact that it never has to surface to breathe may confuse some that are just learning about plesiosaurs. Also, it appears to use its tail to swim more than its flippers, which is totally incorrect and, unfortunately, therefore very misleading.