Photographing the humpback whales of Tonga has been on my personal bucket list for a number of years and finally in 2015 I got to spend nearly three weeks in Neiafu, the main town in the Vavu’a island group in the north of the archipelago, where the majority of the whale watching takes place. The 170+ islands that make up the nation of Tonga are stretched out over a 800km long archipelago, located about 1600 km north-east of New Zealand in the western Pacific Ocean and are basically a long way from everywhere – even for Australians like me!
Tonga is one of the few places in the world where a limited number of swimmers are allowed in the water with the humpback whales that visit every winter. Which means rather than photographing them from a boat with numerous other people, you can be in the water eyeball to eyeball when the opportunity presents!
Although I have been diving for many years and visited many locations Tonga was my first experience of snorkeling with such large creatures – the average mature humpback whale is about 14m (45ft) long and weighs about 35 tons!
It was an incredible experience overall and the objective of this article is to share the key points and explain a little bit about the photographic equipment and technique used.
1) The Annual Migration of the Humpback Whales of Tonga
Before we get in to the details let me provide a quick overview of why the whales are there as it is extremely relevant to the encounters with the humpbacks – “encounter” is the term used to describe the in-water interactions with the whales and it describes the whole thing well.
“To come upon or meet with, especially unexpectedly” is how my dictionary describes an encounter and that is exactly what it is like in-water with the humpback whales of Tonga!
What that means is that you have to be ready with your camera and housing when the moment happens… Back to the annual migration!
Every year by about May, the average day-time temperature in the Antarctic has fallen to around -20 Deg C, and the humpback whales of the southern hemisphere know the time is approaching for them to head north in one of the world’s largest and longest animal migrations.
The cold waters of the Southern Ocean that surround the Antarctic ice cap are an incredible crucible of marine life which sustains an amazing variety of creatures and the humpbacks have spent the summer months gorging on the huge swarms of krill that abound there.
Krill are considered one of the most successful and abundant species on the planet and are a critically important primary element in the Antarctic food-chain. They thrive in the Antarctic summer because of the sheer abundance of phytoplankton – tiny organisms that live near the surface of virtually all oceans and exist by photosynthesizing light energy from the sun into chemical energy that sustains them.
The fine balance of a profusion of phytoplankton creating an equal abundance of krill, which in turn allows the southern humpbacks to restore their body mass in preparation for their mammoth annual migration, is one of the many wonders of the Antarctic!
For the whales of the “Tongan Tribe” their migration involves a journey of over 6,000 kms which takes them up the east coast of New Zealand in to the waters of the South Pacific and then along the sub-sea volcanic arch that leads to the archipelago of 170 plus islands that forms the Kingdom of Tonga.
These epic migrations are integral to the humpback whale’s cycle of life and their survival as a species, as the waters of the Antarctic are too cold for newly-born calves to survive, so the pregnant females swim all the way to Tonga to give birth in the warm waters and sheltered bays of the of the Tongan islands.
Once they leave their Antarctic feeding grounds there will be very little to eat – which is why they must bulk up in preparation by consuming up to 2 tons of schooling fish per day, building up a 150mm thick layer of rich, fat blubber which will sustain them through the winter months ahead.
Bulking up is particularly critical for the pregnant females who lose around 25% of their body weight by the time they have given birth, nursed the calf in Tongan waters and then guided it back to the southern feeding grounds.
Come spring when the return journey begins that order is reversed with the pregnant females leaving first and the mothers and calves departing last.
That first passage south, and the return journey some 5 to 6 months later, is when the calf learns the long migration path between the Antarctic and Tonga it will use for the rest of its life.
2) Encounters with the Humpback Whales of Tonga
There are basically six main types of encounters you may experience in Tonga, and they range from the wonderfully endearing observation of a mother with her calf to the incredible intensity of a heat run.
2.1) Mothers and their Calves
The many sheltered bays of the Tongan island provide the perfect spots for the mothers to recover their strength after giving birth and feed their young calves as they prepare it for the journey south again at the end of the season.
The bays also provide reasonable protection from the many predators whose modus operandi is to separate the vulnerable calf from its mother and then kill and eat it!
Approaching a mother and her calf has to be done with great care, typically with a silent entry in to the water about 100m away and then a slow and equally quiet approach. A qualified guide has to be with you at all times and they read the situation and maneuver accordingly to try and get you in the best position but without upsetting the mother who will move away at the first sign of danger.
Let me just say that being in-water so close to a mother and her calf and observing the incredible bond between them will pluck the heartstrings of even the most seasoned observer!
2.2) Heat Runs
At the complete other end of the spectrum is the heat run and these occur when a single female humpback whale signals that she may be ready to mate, which she does that by repeatedly slapping her huge pectoral fins on the surface of the water.
For any male whales in the area this is the siren call they have been waiting for, in fact it’s the basic reason they have swam over 6000km from their rich feeding grounds in the Antarctic to the Tongan archipelago in the western Pacific Ocean!
But… to win the grand prize and be the one to mate with the lone female the male humpbacks know they will have to duel with and outwit all the other hopeful aspirants. It is a truly Darwinian contest that only the strongest and most capable males have a chance of winning – thus ensuring the purity of the blood-line.
Heat runs with up to 14 male whales chasing a single female have been observed. Do the math… each of those animals is around 14m long and weighs about 35 tons, which means there is a potential physical presence of over 500 tons of large mammals swimming at speeds that can reach 15mph and all focused on one thing – procreation!
To say that it is a seminal experience would be something of an understatement… I can honestly say that in over 30 years of diving I have never seen anything quite like it!
Positioned properly you will be in the water about 100m in front of the whales as they appear out of the blue looking like a small armada of submarines, coming right towards you with the female in the lead and the males in a pack behind.
The males are jostling and maneuvering for position with some trying direct charges at their rivals to try and knock them out of the race, while others will try a covert approach by diving down and blowing a bubble curtain up in to the path of a male to try and disorientate him.
There is a lot of kinetic energy going around and the heat run can go on for hours till it is all exhausted and the female is finally alone with the winner, which means that if you are lucky and have a good skipper you can get multiple “drops” as the whole spectacle unfurls before you!
2.3) Escorts
These are the close encounters with the mature “escort” whales who guard and protect the mothers and calves by running interference between them and the perceived threat (you…), which provides for some stunning photo-opportunities.
The escorts are usually males and their intentions are not completely altruistic as they are hoping to be rewarded for their services by being allowed to mate with the mother at some point…
It is not known why females sometimes act as escorts.
2.4) Competitive Groups
These occur when an interloper tries to force out an incumbent escort whale, producing some spectacular interactions as the candidates fight it out and the mother does her best to protect her calf.
Although not as intense as a heat run they can provide incredible photo-opportunities when they do occur because the interactions take place before you if you are lucky as opposed to the drive-by shooting atmosphere associated with a heat run!
2.5) Singers
These are the male whales who produce the incredible whale songs that travel huge distances underwater and are believed to play a part in the mating process.
Humpbacks don’t have any vocal chords, but the singers produce their complex “songs” by circulating air through the various tubes and chambers of their respiratory system while in a vertical position in the water.
The singers remain almost completely motionless in a vertical position when this happens and they appear to enter an almost zen-like state, so it is possible to get quite close to them and observe that meditative situation.
2.6) Playful Calves
If there is an element of danger about being in the water with the humpback whales of Tonga, the playful calf is about as bad as it gets!
Newly born calves are 3-4m long, weigh up to 1 ton and are a significant animal in their own right even though they seem quite small compared to their mothers. Initially they are quite timid and the mothers are very protective, but consuming as they do up to 200 litres of its mother’s fat-rich milk per day allows the calves to grow quickly and as they do they start to demonstrate playful behaviour at the surface such as breaching and tale slapping.
It is believed that this is to strengthen the calf in preparation for the long migration south and so the mother will allow this cavorting around while watching for potential predators.
The calves are very inquisitive and may come over to check you out and although not aggressive in nature the calves have very little spatial awareness, unlike the mature whales that always seem to know exactly where you are.
So the risk is that you may get side-swiped by the calf’s pectoral fin or fluke as it turns or, even worse get caught in a tale slap!
But the risk is well worth it in my opinion as the interaction with the calves is a sheer delight as their youthful energy and enthusiasm seems to positively radiate and makes such encounters truly memorable.
My three weeks in Tonga flew by and I learned so much about these incredible creatures from seeing them in the water and then researching the behavior I had observed.
I have documented what I learned on my site, www.indopacificimages.com. If you are interested in understanding more about the humpback whales of Tonga, their annual migration and the incredible encounters possible please follow this link.
2.7) Equipment Used in Tonga
My primary camera and the one I used for 95% of the images I captured was a Nikon D800 in a Nauticam housing, which was great for image quality but rather frustrating when shooting in high speed Continuous “C” mode as the buffer quickly filled up…
This was my first real experience underwater with the D800 as a “sports” camera as I normally use it with flash (strobes…) in Single “S” mode and I quickly realized why people who do this sort of shooting a lot go for the top of the range models with huge buffers!
It taught me a lesson as I had to use the C mode sparingly (shorter bursts) to avoid the buffer filling up and the camera stopping just as the whales came closest! It also convinced me to move to the new D500 as I am planning to photograph the sperm whales in the Azores later this year.
I also had an Olympus OM-D E-M1 mirrorless camera in a Nauticam housing as a back-up but found it poorly suited to the task and sold it soon after returning from Tonga.
I used a few different lenses – two that I knew very well: Sigma 15mm f/2.8 fish-eye and the Nikon 16-35 f/4 rectilinear zoom, mainly at 16mm… Plus I also tried a Tamron 14mm f/2.8 prime and a Tokina 17mm f/3.5, with pretty mixed results – the Tamron was pretty sharp but suffered from excessive vignetting while the Tokina underwhelmed me for this application.
Hopefully you found this article to be interesting. Photographing humpback whales in Tonga is something I have wanted to do for a long time, and I was very excited to share my experiences with Photography Life readers.
This guest post has been submitted by Don Silcock, based out of Sydney, Australia. You can visit his website for more images and articles related to his travel adventures.
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