Mr Singer said the Ministry for Primary Industries (MPI) had been notified and the four men were expected to face charges.
He said paua poaching was "always a problem from this time of year onwards" on the CHB coast, and he thanked the public for alerting police to the men's car and their suspicious activity.
"We can't be everywhere - we need the public to report these matters," he said.
An MPI spokesman said the quartet were yet to be charged and MPI was continuing its investigations.
The alleged paua poaching comes as police reveal they will be increasing their presence to prevent stock theft and illegal poaching on land.
Police said there would be more patrols and checkpoints in northern Hawke's Bay and southern Tairāwhiti from today until Sunday.
Maximum penalties for unlawful hunting under the Wild Animal Control Act were fines of up to $100,000 plus up to two years in prison.
Police warned that hunting-related items including firearms, knives, dogs, GPS units and vehicles could also be seized and forfeited.