"These are popular beaches and you get one person who ruins it for everybody else."
Lyle said large launches creating large wakes could also cause "quite a lot of grief".
"It's not so much related to speeding, more not slowing down enough and the skipper needs to actually look behind them and see what kind of wake they are making as it carries a long way and can do actual damage to other boats."
He said there had been several reports of smaller vessels anchored together that had been smashed together from the wake of large launches.
However, he was not expecting as many launches on the water over the next two weekends.
"I think there will possibly be more trailer boats as a lot of the larger ones, such as launches, stay up a good few weeks over the Christmas period and then go back."
Hot spots being patrolled were Mangawhai, because of its proximity to Auckland, and Kai Iwi Lakes – a small area for a lot of vessels.
Deputy harbourmaster Laurence Walkinshaw said a lot of people were under stress last year and, come the holidays, had launched new toys.
"We're talking generally good law-abiding people but they're just unaware of the rules."
He added: "Many boaties have gained their knowledge passed down through the family which is fine but vessels today are a long way from granddad's tinny, especially jet skis, which are far more powerful.
"A lot of people who buy a boat with no education at all. We also meet people who have been on the water for quite a long time and are still unaware of rules, such as basic navigation and collision avoidance."
Skippers are legally responsible for the safety of the boat and everyone on board and Lyle recommends undergoing at least a day skipper's course.
If harbourmasters observe poor behaviour, they will first educate those responsible or, if it's more serious, take names for a written warning or a fine of up to $200.
As well as complying with the boating safety code and local bylaws, Lyle advises boaties "be prepared, check your boat and take necessary safety equipment with you such as life jackets and two forms of communication".
• The free Coastguard app can be downloaded for logging trips and features marine weather forecasts and tides.
Some common rules at sea:
• You must not exceed five knots (a fast walking speed) if you are within 200m of the shore, any structure or a boat displaying a diver's flag; or within 50m of any other boat or a person swimming.
• When giving way and power meets power, powerboats must give way to those on the starboard (right) side and when meeting head-on, powerboats must turn starboard. If power meets sail, paddle or rowing craft, powerboats must give way unless the craft is overtaking.
• If you are in a channel or harbour you must keep to the starboard side of any channel, keep clear of larger vessels that are restricted by channels, not anchor in a channel or anywhere that could be dangerous to other craft, stay at least 500m clear when ahead of any large ship and stay 200m away from the sides and stern of tankers.
• Further information, including an online quiz, can be found at www.boatingeducation.org.nz or www.maritimenz.govt.nz
