The American Bird Conservancy is warning that the old PVC mining claim markers are luring millions of birds to their deaths across the western U.S. and has launched efforts with federal and state agencies across the region to remove the pipes from public lands. Arizona's state bird, the cactus wren, is identified as one of the species affected.
According to ABC, "Small birds apparently see the opening of PVC pipes used to mark mining
claims as a hollow suitable for roosting or nesting or possibly
gathering to pool body heat during migration. The birds may enter the
holes, only to become trapped because the walls are too smooth to allow
them to grapple their way up the sides and the pipes are too narrow
for the birds to extend their wings and fly out. Death from dehydration
or starvation follows." [Right, PVC claim markers in Nevada. Credit, ABC]
Surveys in Nevada and Oregon found an average of one or two dead birds per pipe stake, with highs in the low 30's. ABC said, "A 1993 Nevada law prohibits installation of new uncapped or uncrimped
pipes for marking the boundaries of mining claims in an effort to
prevent injury to wildlife. However, about half of the protective caps
that have been installed on markers since then have become displaced,
thereby re-establishing the hazard from the pipes. .... a
subsequent law ruled that stakes without caps or crimps would no longer
be recognized as claim boundary markers."
There were 3.4 million mining claims in the 12 western states as of 2010, with a minimum of 4 stakes per claim, but there is no count of how many are PVC pipes, and of those, how many are open at the top.