GothHobbit
Also GothHobbit on iNat.
I started using this nickname 20+ years ago so that people at our local Science Fiction convention (MileHiCon, 54 57 years as of 2025 and still going strong!) would be able to distinguish me from the multipack of other Beccas – half of whom were also redheads.
It’s less of a nickname and more of a fairly apt description.