Our time spent with the TV, Internet and video games is taking away from time spent with nature, according to new research funded by The Nature Conservancy.

This growing penchant for “videophilia,” as the researchers described it, not only makes us less likely to conserve our environment and care for national parks, but also is harmful to our health, the researchers say.

Camping, fishing and visits to parks are all declining as more of our recreation turns from outdoor to indoor activities, researchers reported online this week in the Proceedings of the National Academy of Sciences.

And if we stay indoors all the time, we can expect our physical and mental well-being to decline as well.

“The replacement of vigorous outdoor activities by sedentary, indoor videophilia has far-reaching consequences for physical and mental health, especially in children,” said Oliver R.W. Pergams, a co-author of the study, in a statement. “Videophilia has been shown to be a cause of obesity, lack of socialization, attention disorders and poor academic performance.”

By examining the number of visits made to national and state parks and counting how many hunting and fishing licenses have been issued over several years, the researchers documented declines of between 18 percent and 25 percent in various types of outdoor recreation.

The decline, found in both the United States and Japan, appears to have begun in the 1980s and 1990s, the period of rapid growth of video games.

For example, fishing peaked in 1981 and had declined 25 percent by 2005, the researchers found. Visits to national parks peaked in 1987 and dropped 23 percent by 2006. Japan suffered similar declines.

Backpacking increased somewhat, but that may reflect a switch from camping to taking day trips, the researchers said. Hunting statistics, on the other hand, remained stable, perhaps because fishing stocks are diminishing while deer populations are growing more vibrant.