I’d been noticing these for some time. Cable ties (aka “zip ties”) left orphaned after fulfilling their original purpose of holding something to something else. Are these the secret plastic litter creating an ecological problem of the future, or just an indicator of the plethora of social events in your area?
I thought I’d better start recording them in case they get cleared up.
I’ve happened across a blog written by Doctor Space Junk, who has been doing some serious research into cable ties as space age archaeology. Some fascinating reading; you can find her cable tie-related articles here. Her work pre-dates my rather random observations by years.