It's a way of protecting the trees, and making sure they survive the winter and beyond. Leaves die during the winter months. If those dead leaves stayed on the trees, and new ones wouldn't grow in their place, the tree would have no way of making food for themselves.
Hope it helps. ☺
Environmental scientists are using GPS ( It is effective but expensive) aerial monitoring (Quick but not the easiest), RFID tags, (mostly for long-term monitoring) and hidden cameras are used to study polar bear behavior without interruption to their environment.
Is there anything you need help with for this problem? I need to clarify first before answering your question.
The answer is confirmation bias. This is the tendency to look for evidence that will confirm ones hypothesis and ignoring anything else that does not lead to the hypothesis. In this situation confirmation bias is evident due to the fact that you look for anything that confirms your hypothesis and ignore anything else that does not point to drug abuse.
