Two women have narrowly escaped prosecution after reports they repeatedly hit a leopard seal on Timaru's South Beach.

The Conservation Department (DOC) launched an investigation this month after it was alerted to the situation.

Witnesses said they had seen the women hitting a leopard seal, which had been resting on the beach, with sticks.

DOC confirmed that the women were formally interviewed. They were issued with a formal warning after it was found they were not aware they had committed an offence.Raukapuka area programme manager Janine Sidery said the pair would not be prosecuted because of a lack of malicious intent.

Ms Sidery said, however, that their actions did constitute disturbing and harassing a leopard seal.

"It was sobering for the women to learn that they had placed themselves in considerable personal danger and from all accounts they were very lucky that the seal did not attack them.

"These leopard seals can move very quickly and if they feel threatened, might bite or chase people."

Adult leopard seals could weigh 270 to 300 kilograms so it was vital to give them a wide berth and not go between them and the sea, she said.