Run-over is really a big issue and is discussed since past.
I had a discussion with my friend from Kerala who is passionate about railways and technologies like me.
The actual region where runover takes place has series of gradients. There are many trains which pass through this region and most of them are with 20 to 24 coaches. The speed restriction of 65 kmph should be maintained on the gradient otherwise train will stall if speed goes below it. So train can't start on the gradient until any banker (another locomotive pushes train from behind) comes and helps.According to loco drivers, they follow necessary majors, like honking horns from distance to alert elephants and other mammals.
But of course the life of an elephant is more important than delay in reach for the train.
We discussed some remedies like, Use of ultrasonic sound as train approches to keep mammals away from the track. This technique is used in Australia to keep kangaroos away. I don't know whether this technique is hygienic for such mammals or not.
It is heard that, there are discussions going on between Southern Railway and Forest Department of Kerala.
I have my Rail-fanning group in Kerala which may push-up this issue and support other conservative groups. Will do my best.
Also there are other such places where this problem is seen. Like one in North-East West Bengal i.e. Mahanada Wildlife Sanctuary which features Elephants. I have traveled on this route which goes from New Jalpaiguri to Guwahati through Sanctuary.
Thanks & Regards