Guernsey does not have a native squirrel population, largely due to the lack of woodland needed to sustain them.
As grey squirrels are classed as an invasive species, authorities are legally unable to release them into the wild if captured.
Byrne said Elvis is now a “a local celebrity”, adding it is “remarkable that after all this time he continues to evade capture and appears to be doing so well”.
Anyone who spots the squirrel can report their sighting to the GSPCA with as much detail as possible, including the location, date, time and a photograph.
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