Green’s Dictionary of Slang

skipper n.⁴

a maggot.

1865		Dundee Courier 13 Dec. 4/4: It is further reported that skippers (maggots) the size of wood-chucks [...] were seen to emerge from the spongy mass.
1871		Royal Cornwall Gaz. 14 Oct. 7/1: After cooking the ham they found it was unfit for food, there being thousands of ‘skippers’ in it.
1882		Millheim Jrnl (PA) 24 Aug. 1/4: Do you think you can come here, with your old fly-blown cheese, full of skippers.
1906		Whitstable Times 29 Sept. 7/6: Cheese and Ham Skippers. The small cylindrical maggot found in cheese [and] smoked ham [...] is familiar to almost everyone by reason of its wonderful skipping and leaping powers.