New Zealand startup, Halter, has raised $220 million in a Series E at a $2 billion valuation with Founders Fund, founder and CEO, Craig Piggott. Halter uses a solar-powered collar, network of low-frequency towers, and smartphone app to create virtual fences, monitor every animal around the clock, and move their herds without ever leaving the farmhouse. The collar also tracks animal health, fertility cycles, and alerts when individual animals may be sick. Halters' success comes as a financial boon for farmers who can increase their land productivity by up to 20% by ensuring cattle graze more efficiently and leave less grass behind. Despite the challenges of drones, Giggott believes the collar will be the right form of fencing for a very long time.