As a pod of "pretty dolphins" pop up next to the research boat David Donnelly is skippering, even the seasoned researchers seem caught by a wave of delight.
The common dolphins have a stripe down their side and are popular on the survey vessel, named Delphinidae, because they tend to leap from the water more than their bottlenose compatriots.
Mr Donnelly, a marine researcher with the Dolphin Research Institute, has been tracking the movements of dolphins and whales in the waters off Victoria's coast since the 1980s.
On the Delphinidae, in water off Dromana in Port Phillip Bay, one researcher spotted a familiar common dolphin with a severely damaged fin.
It was the second dolphin to surface near the white and blue runabout with a healed injury, but Mr Donnelly said it was the whales that were cause for concern.
Blue whales have been showing up around Victoria looking underfed.
"It's quite clear that they're coming back not in the condition that you would expect them to, so they're not doing as well on that migration period," Mr Donnelly said.
At the Bonney Upwelling off Portland, in Victoria's west, the blue whales feed up, feasting on critters like krill.
"On last inspection, these animals seem to be doing much better," Mr Donnelly said.
Whale migrations overlapping for first time
Blue whales are the biggest on earth and travel huge distances to feed, breed and calve.
They arrive in the waters off Victoria for summer and normally move on again early in autumn, but last season they stayed longer.
It meant those giants of the deep and southern right whales overlapped on their migration.
"That is really quite uncommon, in fact, that's the first time it's been recorded on the Victorian coastline," Mr Donnelly said.
"We saw blue whales in early July, which is when the southern right whales are starting to settle to have their calf."
Citizen scientists help track whales
The Dolphin Research Institute counts and monitors whales using research boats like Delphinidae and by relying on members of the public, dubbed citizen scientists.
The volunteers send photographs and location information about whales back to the experts who then compare it against their records to see if a whale snapped is one that is familiar.
"Citizen scientists give us a chance to capture all the sightings of whales around Victoria's coastline that would otherwise just go on someone's Facebook post or just be told over a dinner table," the institute's executive director Jeff Weir said.
"The majority of the information logged in the Dolphin Research Institute's database comes from these members of the public.
"Those citizens all out there with their eyes, reporting the sightings, means that we can start to get a picture of what's really going on off Victoria's coast."
It means they have a huge amount of information to rely on, much of it relating to humpback whales – and their behaviour has changed too.
Humpbacks enjoying the cool waters
Usually humpbacks flirt and calve in warmer waters but this year they were seen romancing here in the cold.
"Behaviours which we normally associate with the tropics or sub-tropic areas of Queensland and Northern Western Australia," Mr Donnelly said.
"Things like calving, mating behaviours, humpback whale song."
As to why these changes are happening, and whether they were related to climate change or other factors, Mr Donnelly said more research was needed.
"There's a lot of potential answers to this question," he said.
"It's no coincidence that the marine environment is changing and so, too, will the animals that live within it.
"We might be seeing a bit of a climate effect or a change over time which these animals are responding to.
"These animals, and most animals on the planet, work through environmental cues such as temperature, light, and in the ocean it's also got to do with currents."
Oceans becoming 'much louder'
It's not only in Victorian waters where whales have been caught acting strangely.
Melbourne University mathematical biology researcher Stuart Johnston has studied the impact of ocean noise pollution on the way whales communicate and migrate.
"The ocean is becoming in general much louder," Dr Johnston said.
"We found that there's an increase of about 10, or 15 per cent in the time taken for them to take a relatively common migration pathway."
Under perfect conditions, whales were able to interact over around 100 kilometres, but Dr Johnston said too much noise could disrupt the way they talk to each other.
"We know there's increasing human activities in the oceans — anytime you have a large container ship, it just adds to the noise in the ocean," he said.
His modelling-based research focused on the northern hemisphere, looking at minke whales in the North Sea, where there was lots of information available on shipping traffic.
"We don't really know if certain whales would be affected more than others," Dr Johnston said.
"But the east coast of Australia, the west coast of Australia are still shipping pathways, so it's all about how much noise there is for a certain location."
Whales use sound in the way humans use their eyes to understand their surroundings.
While Mr Donnelly compared blocking that sound out to turning the lights off.
"It's important that we monitor what sort of sounds we're putting into the environment, whether that be shipping, recreational boating, exploration, drilling," Mr Donnelly said.
He said sound was only part of the puzzle.
"Animals are fairly well attuned to where they want to go and where they want to be," Mr Donnelly said.
"All of those things that we do have an impact on these animals."
