Herd of cows commit mass suicide

[Kaleva]

"Farmers in Switzerland have been left baffled after a herd of cows jumped to its death off of a 50metre-high cliff last week.

The 13 Herens cows broke through their pen and through several lines of security around their pasture before running toward a cliff and either falling or throwing themselves off of the 50metre drop near Levron in Valais on Wednesday."

http://www.dailymail.co.uk/news/article-4573442/Herd-cows-jumps-50-metre-Swiss-cliff.html

[Tanuki]

1. American bison will do this. Native American groups on the plains

would drive herds of bison over a cliff as a hunting strategy.
https://en.m.wikipedia.org/wiki/Buffalo_jump
"Hunters herded the bison and drove them over the cliff, breaking their legs and rendering them immobile. Tribe members waiting below closed in with spears and bows to finish the kills. The Blackfoot Indians called the buffalo jumps "pishkun", which loosely translates as "deep blood kettle". This type of hunting was a communal event which occurred as early as 12,000 years ago and lasted until at least 1500 AD, around the time of the introduction of horses. The broader term game jumpsincludes buffalo jumps and cliffs used for similarly hunting other herding animals, such as reindeer. The Indians believed that if any buffalo escaped these killings then the rest of the buffalos would learn to avoid humans, which would make hunting even harder.[1]

Buffalo jump sites are often identified by rockcairns, which were markers designating "drive lanes", by which bison would be funneled over the cliff. These drive lanes would often stretch for several miles.

Buffalo jump sites yield significant archaeological evidence because processing sites and camps were always nearby. The sites yield information as to how the Native Americans used the bison for food, clothing and shelter. Plains Indians in particular depended on the bison for their very survival. Every part of the animal could be used in some way: hides for clothes and shelter, bones for tools, sinews for bowstrings and laces. Hooves could be ground for glue, and the brains could be used in the tanning process for the hides. The extra meat was preserved as pemmican.[2]

In one of his journals, Meriwether Lewisdescribes how a buffalo jump was practiced during the Lewis and Clark Expedition:

one of the most active and fleet young men is selected and disguised in a robe of buffalo skin... he places himself at a distance between a herd of buffalo and a precipice proper for the purpose; the other Indians now surround the herd on the back and flanks and at a signal agreed on all show themselves at the same time moving forward towards the buffalo; the disguised Indian or decoy has taken care to place himself sufficiently near the buffalo to be noticed by them when they take to flight and running before them they follow him in full speed to the precipice; the Indian (decoy) in the mean time has taken care to secure himself in some cranny in the cliff... the part of the decoy I am informed is extremely dangerous.[3]"......(more)

[Kaleva]

2. The decoys must have had exciting but short lives!