INDIANAPOLIS, Ind. (WOWO)  — Indiana Conservation Officers are warning Hoosiers to take extra care on frozen lakes, ponds, and rivers as winter activities ramp up statewide.

While thousands safely enjoy fishing, skating, snowmobiling, and hiking on the ice each year, officials say drownings also occur annually when people venture onto ice that is thinner than it appears. Their message: assume no ice is safe ice unless its thickness has been measured.

The DNR recommends testing ice with an auger and says at least four inches is needed for ice fishing and five inches for snowmobiling. They also urge anyone heading onto frozen water to wear a life jacket or flotation coat, carry ice picks and rope, and let someone know where they plan to be.

Snow cover adds another hazard, acting as insulation that slows freezing and hides weak areas. Ice created by snow and rain refreezing is also less sturdy than clear, solid ice.

Officials warn that flowing water, underground springs, sand-bottom areas, and spots frequented by wildlife can all create unexpectedly thin patches. They also caution residents not to attempt rescuing pets or animals that fall through the ice; trained emergency crews should be called instead.

The DNR says winter recreation can be safe and enjoyable as long as Hoosiers treat ice conditions with caution and respect.

More information and safety updates can be found on the DNR website.