Both waterspouts and landspouts sometimes occur with rope-like multiple funnels. Waterspouts are not uncommon in tropical and sub tropical waters. In the U.S., they can be seen in the Gulf of Mexico, off the Florida east coast and in the vicinity of the Florida Keys. However, they're not limited to these areas, but they occur much less frequently elsewhere. For example, a waterspout was photographed over lake Tahoe last September - the water in this deep cold water lake is warmest in late summer.
Waterspouts soon dissipate after coming on-shore.
To my knowledge, watches or warnings are not issued for waterspouts as they are for tornadoes. When a tornado happens to traverse a river or lake, it's referred to as a tornadic waterspout. Unlike a hurricane, a tornado may lose a little energy over the water since water sucked up into the tornadic engine can act to dampen the rotation. A gustnado is an even smaller tornado than a landspout. Bursts of air, downdrafts, along the leading edge of rain-cooled air flowing out of a thunderstorm can create a gust front.