Thankfully most people I know are sufficiently environmentally enlightened that they would never dream of throwing their empty coke cans out the car window or leaving their energy bar wrappers along the side of a hiking trail. Unfortunately, many people aren’t quite so careful when it comes to disposing of things like fruit peels, chicken bones, or even that empanada that looked better than it actually tasted. The justification for this difference in behavior is that items like the latter three are biodegradable and will eventually break down in the environment. The problem with this argument is that even food scraps won’t biodegrade very quickly in many environments and can cause plenty of other problems before they do.
Very few people would attempt to defend leaving food scraps on an urban sidewalk, but I’ve seen a lot of those same people throw apple cores or banana peels out of the windows of their car, or worse yet out the window of my car while I’m driving. Not only does this risk getting pulled over if done in the US, but it also risks contributing to the deaths of cute and fuzzy wild animals. If too many food scraps start piling up along the roadsides, animals like foxes and coatis will come and try to scavenge them, and some of those animals will inevitably end up as road kill. Less appealing animals like rats and crows are also attracted to roadside food scraps and this food subsidy can cause their populations to increase beyond natural levels, which is obnoxious both for human communities and for animals like lizards, salamanders, and songbirds, which are hunted and harassed by these voracious mesopredators.
Attempts at ‘trailside composting’ can also be problematic. While it is probably not harmful if done infrequently in hot and humid environments like tropical rainforests or cypress swamps, it tends to cause issues if overdone or if done at all in habitats less favorable to decomposition. Food scraps left in deserts tend to become mummified and orange peels left above tree line in the mountains tend to freeze-dry to the texture of Styrofoam and probably take just about as long to decompose. Leaving large amounts of food scraps along the trail or at your campsite also significantly increases the odds that the next camper will be overrun by rodents like mice, who carry hantavirus, or marmots, who have been known to amuse themselves by chewing holes in gear. Finally, it is worth remembering that mountains and other wild places are sacred to many indigenous peoples and leaving your picnic scraps at the summit is as disrespectful to indigenous beliefs as leaving chicken bones on the floor of St. Peter’s Basilica would be to Catholicism.
A final excuse used for slinging one’s scraps is that they decompose more effectively in in the natural environment, or even on concrete, than they would in a landfill. Unfortunately this may be true, but that’s justification for composting at home or pressuring the local government to start a municipal program, not for flinging one’s organic trash around like an outraged two-year old. For the sake of wild animals, ecosystems, hygiene, and aesthetics, remember: “If in doubt, pack it out.”
 Anyone who does this more than once walks home.
 Carnivorous or omnivorous animals, which occupy the middle of the food chain.