Long telephoto lenses were meant for times like these. This was a scenario where I couldn't get any closer – wetter was not an option I was willing to accept. Not only did this lens's 600mm focal length make the animals substantial in the frame but the f/4 aperture created a blurred background even at this long distance, making the subject stand out.
I am considering a return to Rocky Mountain National Park in September.
Let me know if you want to be part of this trip!