for light cars, and large ATVs and a minimum of 14 inches (36-41 cm) for full-sized trucks. Thinner ice in areas with swift surface currents are a significant hazard, as is ice that is directly over underwater spring. Hazards to Ice Offshore winds can break off pans of ice which are miles wide, stranding large numbers of fishers. Just such a circumstance occurred in Lake Erie in February 2009, with 100 fishers having to be rescued by helicopters, local authorities, and the Coast Guard. One man who had fallen into the water died on the rescue flight. On March 28, 2013, as many as 220 ice anglers were trapped on break-away sea ice floes in the Gulf of Riga (Latvia), necessitating a full-scale rescue operation which employed helicopters and hovercraft. Many similar operations—although typically much smaller in scale—are required each year due to reckless and/or inexperienced anglers. Late-winter warm spells can destroy the texture of the ice, which, while still of the required thickness, will not adequately support weight. It is called "rotten ice" or soft ice and is exceedingly dangerous. Some ice anglers will continue to fish, since even with the bad ice normally 8 inches (20 cm) is more than enough. Ice anglers may carry a self-rescue device called an ″ice pick″ made of two spiked handles connected by a string to pull themselves out of the water and onto the ice. Hazards to People Many cars, trucks, SUVs, snowmobiles, and fish houses fall through the ice each year. Current environmental regulations require the speedy recovery of the vehicle or structure in this situation. Divers must be hired, and when the trouble occurs far from shore, helicopters may be employed for hoisting. Other risks associated with ice fishing include carbon monoxide poisoning from fish house heaters and frostbite due to prolonged exposure to wind and low temperatures, although most new houses are fitted with air exchange systems that allow air flow, preventing poisoning. Although fatalities are somewhat rare, in the year of 2017, 56 people died while out on the ice in USA and Canada. Fatalities almost always occur from drowning after one has fallen into the ice, although a small number of victims died from blunt-force trauma (e.g.: hitting one's head on the ice whilst falling in the water). Contests Anywhere there is fishing, there are contests, and ice fishing is no exception. Ice fishing contests generally