Many ponds throughout the UK have terrapin(s) in them as a result of having been illegally dumped after the Ninja Turtle craze died away. There is a pond near me that has one.
I very much doubt if the Loch Ness Monster was the sort of answer the rangers were expecting, judging by the quality of question posed in the rest of the quiz-its not the type of "tongue in cheek" questions to try to test initiative, more hard facts, but thanks for the thought.