As I surveyed my seep and determined the damage from winter storms—which trees toppled over in an arch or flattened wild grapes, I also found a half-buried lawn mower, an old tire, part of a metal rowboat and a paint can wedged under a stone wall. I have decided to make use of some of these strange artifacts for a sunken garden. They are after all common indicators for wetlands.
For decades, scientists have tracked the migration of shopping carts (Grocer currus) from urban areas to wetlands. In one recent pilot study, wetland scientists reintroduced the endangered shopping cart, which has been historically held in captivity at local food marts, to a stand of hot sedge (Carex lupulina). The common white bag (Sacco albus) has been spotted in numerous wetlands with few habitat restraints, as it does not seem to require anything to roost in both vegetative and nonvegetative areas. A large inactive docile predator, typically referred to as the old tire (Defessus antiquus) rolls into streams, rivers and estuaries, preferring sluggish waterways, seemingly unaided by breeding populations of abandoned excavator equipment (Effidio paratus). For a funny video, go to:http://www.youtube.com/watch?v=peZRiphnOwE
In addition to traditional field guides, check out The Stray Shopping Carts of Eastern North America: A Guide to Field Identification by Julian Montague (2006), who documents the eerie sightings of the metal migrants in colorful photographs:
Not surprisingly, under human influence, cranes will dance on command. See “Big Machines Dancing” http://www.youtube.com/watch?v=JYzAJviXr0Y&feature=PlayList&p=DA4887DBDE40258D&playnext_from=
PL&playnext=1&index=12 But when left to its own devices, it’s a sad tale when an excavator must be pulled out of a wetland http://www.youtube.com/watch?v=TDjQOyVULUs
Other wetland indicators include the elusive failed storm drainage pipe (Adficio deficio)and the invasive soft drink can (Imbibo aluminus), although more research is needed to determine whether their presence has anything to do with the growing problem of runaway trash cans.