Acronym for "Society for the Prevention of Cruelty to Animals". An organisation of this type is present in most countries, dedicated to the protection of animals in that country. Examples include the "Royal Society for the Prevention of Cruelty to Animals" (RSPCA) founded in Britain in 1824 and the Canadian SPCA (CSPCA) founded in Montreal in 1869.
This is simply a Nodeshell Rescue.