One the Kruger National Park's (KNP) oldest elephants, Duke, who was more than 55-years-old, has died, the park said on Friday. The elephant was discovered lying on its side along Makambeni spruit, five kilometres from Crocodile Bridge Camp on Wednesday, KNP spokesman William Mabasa said in a statement. The five-day-old carcass was found after the camp's section ranger, Neels van Wyk, became worried when there was no movement from Duke's electronic collar. It was believed the animal died on October 1. "Although Duke was old, we are very saddened by this magnificent bull's passing as he was very popular and had avid followers who always asked about him," said Mabasa. "In the past few years, there had been enquiries as to whether Duke was still with us; so when news of his passing came through we assumed it was rumours doing the rounds again." The elephant had lost both tusks and in 2010 was fitted with a tracking collar in an effort to check up on him and his whereabouts. Duke was estimated to have lived in the KNP bush for over 55 years. Following normal practice, the head, tusk remains, and possibly skeleton would be recovered and then stored for possible display purposes. Emerging tuskers are named after previous rangers and field rangers who have made notable contributions to conservation and the KNP. The park said Duke was named after Thomas Duke, who was based at Lower Sabie between 1903 and 1923.