<https://forums.geocaching.com/GC/index.php?/topic/62421-pictures-cool-cache-containers-cccs/page/10/#comment-1293363>
<http://schema.org/text>
"I did a quick and dirty search of the federal code and the only thing I could find that was remotely on point is 50 CFR 21.  This reg pertains to migratory birds and their nests.  It states that the nests of such birds cannot be removed if they are still in use.  If the nest is no longer in use, it can be removed and destroyed (but not kept, sold, etc., go figure   ). \n  \nRemoving an old nest does not require a permit.  Using a fake nest for a cache is perfectly legal and would require no specific permit.  Using an old, unused nest for a cache would, apparantly, require a permit. \n"
<https://forums.geocaching.com/GC/index.php?/topic/62421-pictures-cool-cache-containers-cccs/page/10/&tab=comments#comment-1298367>