The warning from police and conservation chiefs comes after “disturbing” encounters with dolphins and whales in Scottish waters.
Scotland is home to more than a dozen species of cetacean, including bottlenose dolphins, harbour porpoises, Orca or minke, humpback or fin whales.
But tourists flocking to see the creatures have been warned not to get close to them, as it could disturb their feeding or breeding.
Previous incidents have included a photographer in Shetland who circled a pod of killer whales too closely in a boat, splitting the group and stressing them.
On the River Tay, there have been issues with jet skiers harassing dolphins, particularly near Broughty Ferry, near Dundee.
Police Scotland has been supporting Whale and Dolphin Conservation (WDC) and the Scottish Marine Animal Stranding Scheme to help stop disturbances in Scottish waters.
PC Daniel Sutherland, wildlife crime liaison officer, for Highland and Islands Division, said: "Every year we receive reports about water users getting too close to cetaceans and disturbing them.
"This can be to get a photo or simply out of excitement at seeing these wonderful creatures.
"There appears to be a lack of awareness surrounding their protection or sometimes a lack of regard for their safety.
"The workshops allowed us to discuss a number of issues in regards to disturbance with a variety of partners and public attending the forum and I hope the event has provided positive actions
moving forward to help prevent ongoing disturbance we see every year, particularly at hotspots such as Chanonry Point (on the Black Isle)."
"As we approach warmer weather this will undoubtedly lead to an increase in marine craft operating around the coast and this naturally leads to an increase in the likelihood of an encounter with a cetacean.
"It is recommend that anyone watching marine wildlife keep their distance and follow the Scottish Marine Wildlife Watching Code."
To date, 23 of the world's estimated 92 cetacean species have been documented off Scotland's west coast, with many of national and international conservation importance.
The Hebridean Whale and Dolphin Trust, based on the Isle of Mull, has been studying sea-going mammals and also runs whale-watching trips.
Communication officer Morvern Summers said people should use 'common sense' when watching the animals.
She said: "It's coming to the time of year when people want to get out on the water and see whales and dolphins.
"It's all about using common sense.
"Don't get too close or do anything which could disturb them as they may be feeding, or breeding.
"If you do find yourself on the water and whales appear, just maintain your course and don't make sudden moves.
"Don't speed up to get away or make swift changes in direction which could startle them."
Danny Groves, spokesman for WDC, said: "Despite whales, dolphins and porpoises being protected in the UK under conservation regulations, incidents are reported involving personal boats and
kite surfers risking disturbance to dolphins.
"Just like dolphins, people love messing about in the water.
"At WDC we want everyone to have fun, but it's important we are all aware that when we're on the water we're sharing that space with whales, dolphins and other marine mammals for whom the sea is their home.
"There are number of things boat and jet ski users can do including keeping distance, maintaining a steady slow speed, never approach whales and dolphins head-on to or move between, scatter or separate individuals."