The babies were contained among 10 pots found discarded at the side of the car park at Bateman’s Yard Stable, on Birchwood Lane, Somercotes.
The pots carried different labels including one saying ‘Brazilian pink bird-eating spiders’.
But two of the larger pots were run over by a vehicle and it is thought the adults may have been in these and escaped. This type of tarantula is one of the largest in the world - with a leg span of up 10 inches - about the size of a dinner plate.
The abandoned spiders would have died in the pots had they not been found. If any have escaped they are not likely to survive for long in the UK climate as they prefer hot and humid conditions.
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RSPCA Inspector Kristy Ludlam, who attended the scene, said: “The women caller who contacted us was understandably shaken when she realised the pots contained spiders as she is terrified of them. It appears someone ran over two of the pots and the driver told the woman who called us he thought he saw two larger spiders. No bodies were found so it is assumed they may have escaped.
“We collected all the pots and took them to a specialist who found three baby arachnids in them which he believes are bird-eating spiders - in fact when he opened one pot a spider ran up his arm.
“He is keeping all the pots warm and secure as there is a possibility more eggs may hatch. We are concerned that someone would abandon spiders like this. Tarantulas live in a warm and humid environment in the wild and need the same provided in captivity, to meet their needs and keep them healthy.”
n Anyone with information about the spiders should contact the RSPCA on 0300 123 8018. If the spiders are seen, do not attempt to handle them.