Dolphin cruise, Port Stephens

For the next hour and a half the captain is looking for one thing: dolphins. When a group surfaces, the engines slow and everyone drifts to the rail. Sometimes they keep their distance; sometimes they swim alongside or ride the bow wave, and the boat must then hold its course and speed.

The operator is honest about the odds: dolphins and whales are wild animals and sightings cannot be guaranteed. But the bay has a resident population of around 90 to 120 Indo-Pacific bottlenose dolphins, so the animals are not passing through: they live here.

They are not one big pod. A study of 120 regularly sighted dolphins found two communities: a larger eastern one near the heads in a marine environment, and a western one ranging further up the estuary. Each dolphin can be recognised by the notches and scars on its dorsal fin.

The dolphins matter to the people of this coast too. The Worimi call them guparr in the Gathang language, and the NSW Government records that elders traditionally spoke with dolphins about food and looking after each other.

The dolphins themselves are the other constant: reviewers write about pods coming right up under the boat, a mother and her calf, and dolphins seen within minutes. Several praise the crew for keeping a respectful distance and leaving a group alone when other boats were already with it.

Families mention the boom net and the slide as the part their children loved, and the boat as large and clean, with drinks and hot food on board. The listing's rating breakdown gives the guide 4.5, transportation 4.6 and value for money 4.4.

Swimwear and towels for the net are not included, so bring your own, along with a sun hat and sunscreen, as the listing suggests. You cannot bring your own food and drinks on board; lunch and snacks are sold at the bar.

Whether you go in is up to you and the conditions on the day. On a hot summer morning the net is the highlight; on a cool winter day, staying dry on deck and cheering is just as much fun. Pack the swimsuit either way, then decide on the water.

At the Nelson Head station, right at the entrance to the bay, January averages a high of 27.2 °C, ideal for the boom net, while July averages 17.6 °C. National Parks gives May and June as the wettest months and October and November as the driest.

Researchers found that the dolphins prefer to forage after 1pm, and suggested fewer boats then. A morning cruise leaves them more of their feeding time, and morning light on the water is often kinder to your photos.

The dolphin cruise stays inside the bay, so whales are a bonus rather than a promise. For a proper look, a 2.5-hour whale watching and outer island cruise from the d'Albora marina in Nelson Bay heads out through the heads, from $60.

From land, National Parks recommends the Tomaree Head summit, 161 m above the entrance, for whale watching between May and November. At the peak the NSW Government says up to 4 whales can pass a coastal headland in an hour.

The rules exist for good reason. A study in Port Stephens found that with watching boats present, dolphins spent 66.5% less time feeding and 44.2% less time socialising, and were never seen resting. A skipper who waits rather than chases is doing the dolphins a favour.

For swimmers the line is 30 metres, and feeding dolphins is harmful and illegal. Let the dolphins decide how close they come: the best encounters are the ones they choose.

For the boom net, wear swimwear under your clothes and bring a towel and a dry change. Shoes that cope with a wet deck help, and a hat and sunscreen protect you from the glare off the water.

Keep your phone or camera ready rather than in a bag. Dolphins surface briefly and often a little further along the same line, so a burst setting and some patience bring better pictures than chasing each splash.

The cruise boards at Wharf 1, Cruise Passenger Terminal, 40 Victoria Parade, and the operator confirms the vessel and departure point by email or text. Transfers to and from the cruise are not included.

Without a car, a 12-hour day tour from Sydney includes 2 hours of dolphin watching at Nelson Bay, plus the koala sanctuary and sandboarding, from $140.

At One Mile, the Port Stephens Koala Sanctuary has a raised Skywalk at eye level with recovering wild koalas, and opens 9am to 5pm, or 9am to 4pm in winter. At Anna Bay, a centre with shallow lagoons lets you wade among sharks and rays.

For the view of the whole bay, climb Tomaree Head: 2.2 km return and Grade 5, steep but short. From the top you look over the heads the cruise boats pass and the islands where the rare Gould's petrel nests.

It is not suitable for wheelchair users, and prams and non-folding strollers are not allowed on board; collapsible strollers go in the main cabin. If you want a quiet, small boat, the sailing catamaran or the express boat may suit you better.

And no one can promise dolphins: they are wild animals. If plans change, cancelling costs nothing until 24 hours ahead, and you can hold your place now and settle the bill later.