His Land Rover Discovery was also seized by police and is undergoing forensic examination.
On Friday police announced Mr Bridger had been arrested on suspicion of murder, indicating they no longer expect to find April alive.
Police have been granted a final 24 hours to question the former lifeguard. The custody limit expires this afternoon after which he must be released or charged.
Emergency services including the Coastguard, RNLI, RAF mountain rescue and 150 members of mountain rescue teams from across the UK have been searching continuously since April vanished.
They are liaising with more than 60 specially trained search officers.