I see a win-win solution here. The proposed road through the isthmus would be incredibly beautiful and a great opportunity for bird-watching and other eco-activities. In other words, the road can be built and operated to be complimentary with the purposes of the reserve. I also think if the road were built that it should be used for community and commercial purposes too. For example convoys of vehicles would only be allowed to travel on a restricted daily and seasonal schedule that was designed around minimizing disruptions to wildlife - except for medical/disaster emergencies of course.