Home Improvement

I work in a basement office. There is a below-grade egress window, with a 3-4ft ladder and a large plexiglass dome that you can push out of the way.

I noticed a terrible smell when I opened my window the other day, and it was because of a dead mouse that presumably couldn't get out of the recess. On inspection, I found the remains of several more dead rodents there, so this has been a problem in the past too.

Any ideas on how to prevent this? I both feel bad for the dead animals and am disgusted by the smell when they decay. The plexiglass dome has chicken wire for airflow, so I can't necessarily block those off. Maybe there's some method to repell them, or help them escape?