Whale Sharks in the Galapagos Islands: A Guide for Divers
Dr. Simon J Pierce is a co-founder of the Marine Megafauna Foundation, where he leads the global whale shark research program. He’s also an award-winning marine wildlife photographer. About Simon.
The Galapagos Islands off Ecuador are famous for the weird and wonderful land animals that call the archipelago home, such as giant tortoises and finches. Underwater, things are just as interesting. The Galapagos is one of the best scuba diving destinations on the planet.
Whale sharks, the world’s largest fish, are one of the biggest drawcards for ocean enthusiasts. The Galapagos is one of the few areas where they are regularly seen by divers, and it’s the best place to see truly gigantic adult whale sharks.
Who am I, and why this article?
I’ve been a whale shark scientist since 2005, and I’ve been working as a member of the Galapagos Whale Shark Project since its formal inception a few years ago. I’ve joined six whale shark research expeditions in the Galapagos since 2015 (and was there as a photographer in 2014). Aside from these scientific trips, which focus on Darwin Island, I host liveaboard dive trips around the archipelago for Galapagos Shark Diving.
Given this experience, I often get asked about diving with whale sharks in the Galapagos – it’s an expensive trip, and people have often heard that conditions can be challenging. While that’s not untrue, I think any reasonably fit and experienced diver can handle the main sites.
Hopefully, I’ll be answering most of your questions in this post. If not, feel free to ask more in the comments!
Where’s the best place to see whale sharks in Galapagos?
Whale sharks are most consistently seen around the northernmost island, Darwin.
The northernmost islands, Darwin and Wolf, are bathed in the tropical Panama Current from the northeast. While they can dive down into deep cold water, whale sharks typically prefer surface temperatures over 22ºC. As do I. The central and southern islands are more exposed to the cool upwelled waters that form the Humboldt and Cromwell currents so, even though the islands lie right on the equator, the ocean is relatively cold in the south and southwest of the archipelago.
Why is Darwin special for whale sharks?
Darwin Island is one of the only places in the world you can consistently scuba dive with whale sharks. More uniquely, though, Darwin hosts seasonal visits from really big whale sharks. Most of the whale sharks that pass by Darwin Arch are adult females measuring 10–12 m in length.
You’re unlikely to see larger whale sharks, or for that matter any sharks, anywhere else in the world. That’s the real draw – seeing sharks that are (literally) bigger than a bus.
How do you get to Darwin Arch?
Darwin is over 300 km north of Puerto Ayora, the main town in Galapagos (located on Santa Cruz). It’s only accessible by multi-day scuba diving liveaboards. These depart from Santa Cruz or San Cristobal islands, and have one or two week-long itineraries set by the Galapagos National Park administration.
When’s the best time to see whale sharks?
“Whale shark season” in the Galapagos is between June and October. However, it’s important to note that conditions are highly variable at Darwin on a day-to-day basis. No guaranteed sightings here I’m afraid, although you have a good chance. Unless conditions are absolutely awful, there are always plenty of other sharks around at least. I’ve seen hammerheads in every one of my hundreds of dives at Darwin.
Why are the whale sharks at Darwin Island anyway?
We’re not quite sure why the sharks are visiting at this stage. Whale sharks normally spend less than a day at Darwin Island. They’re not regularly feeding, and there’s no obvious socializing between the sharks either.
I suspect that whale sharks use Darwin Arch as a navigational waypoint. Some sharks can detect the Earth’s magnetic field. Historical volcanic eruptions at Darwin Island have created concentric rings of magnetically polarised rock on the seafloor, providing a detailed relief map for animals, if they have the right equipment to read it. Their attraction to this area indicates that whale sharks do.
Many of the sharks head out to highly-productive equatorial front waters after they’ve been at Darwin, so this area might be a thoroughfare to that offshore habitat. (See left – research article here). We’ve deployed satellite-linked tags on quite a few sharks from Darwin now. Once they leave Galapagos, many sharks swim out into the Pacific Ocean, far from any landmass. There’s a long productive zone where cooler waters from the Peruvian coast meet warm tropical waters above the equator and, based on our tracking data, the whale sharks are likely to be feeding out there.
We did think that a lot of the female sharks are pregnant (most have a very large “bump” behind the pelvic fins). Our 2018 expedition used an underwater ultrasound unit to test this, and we’ve also collected blood samples from the free-swimming sharks. The results confirmed that the sharks are adults, but they may not be pregnant after all. That study is ongoing!
Is Darwin Island good for other animals too?
Sure is! I think Darwin is the best dive site in the world. Aside from the gigantic whale sharks, there are always hammerhead sharks swimming around, and you’ve got an excellent chance of seeing lots of other sharks (particularly Galapagos sharks, silky sharks, and blacktip sharks), sea turtles, yellowfin tuna, bottlenose dolphins, and huge schools of fish. It’s one of those places where almost anything can turn up.
What are the dives like?
You’ll normally do four dives per full day at Darwin, one before breakfast, and then three more 2–3 hours apart until 4 pm or so. You’ll be diving out of small inflatable boats, doing a negative entry (with a fully deflated BCD) so you can get to the bottom quickly. Group size is often 7-8 divers per guide, who’ll be leading the dive.
Hopefully, the water temperature will be between 24–26ºC during whale shark season… but if cooler currents are prevailing, which does happen quite regularly, it can drop to around 20ºC. Eep. I wear a 5 mm Beuchat wetsuit, with an Adrenalin rash shirt and a Sharkskin hooded vest for additional warmth. Be aware that you might get cooler waters elsewhere on your itinerary, so a 7 mm wetsuit is a good plan if you tend to feel the cold.
You’ll probably want to maximize in-water time at Darwin, so – if you’re a heavy breather – it’s worth checking in advance if 15l tanks are available on your vessel. Most boats dive on nitrox, which will significantly extend your bottom time, particularly towards your 4th dive at the end of the day. If you haven’t done a nitrox course prior to your trip, many boats can offer in-person courses. Of course, you’ll want a good dive computer to keep watch on your no-deco limits.
Visibility has varied from around 5 m to well over 40 m when I’ve been at Darwin. It’s impossible to predict far in advance, as it depends on the current and other conditions. And speaking of current…
Will there be a strong current?
Possibly. It does happen. If there is a strong current, the best plan is to get behind a rock somewhere. There’s nothing to damage on the rocks at Darwin, except some barnacles, so wearing a good pair of neoprene gloves is an excellent plan. Reef hooks aren’t helpful, as there’s (usually) too much surge. I use fairly powerful fins, which help a lot in the current.
If you’re diving in current, obviously you’ll be drifting as you ascend and complete your safety stop. Darwin is a remote area, so Galapagos liveaboards are generally pretty good (check in advance) at supplying you with safety equipment if you haven’t got your own. That might be a Nautilus locator beacon, a noise-making system for your low-pressure inflator hose, or something similar. Every diver should (always) have their own large safety sausage that can be inflated on the surface.
While you can certainly dive the Galapagos without a lot of experience, to get the most enjoyment out of it, I think it’s best to have a decent level of experience, say 100+ dives. Some recent dive experience before you get to the islands would be useful, too.
That said, the currents aren’t as big a deal as people think they are. You’ll be well-briefed and well-led underwater.
Is Darwin good for underwater photography?
The answer is yes. It’s amazing. However, there are some caveats.
The whale sharks won’t come to you. Typically you’ll be holding onto a rock at 15-20 m depth, and the guides will shake a rattle if they see a whale shark swimming past. If the current allows it, you’ll swim out (fast!) and be able to get photographs of the shark. The quality of your photos will depend a lot on how close the shark is to you, and how well you can position yourself for a good composition. Thing is, they might come through at the surface, or they could swim past deep… for a bus-sized fish, whale sharks have a weird way of sneaking up on you.
All the photos in this article were taken at Darwin. I use a fisheye lens (a Canon 8-15 mm at present) on a Sony A7rIII camera. I’ll use strobes if I can, but be aware that they’ll slow you down when you’re swimming and can be difficult to handle in a current. When I’m working as a biologist I’ll often forego the strobes as I’ve got additional equipment to manage. However, it’s often surprisingly dark underwater if it’s cloudy overhead, or on the first and last dives of the day, so you might have to push your ISO up to maintain a reasonable shutter speed.
I’ll typically shoot in manual mode, often at f/8 at 1/160 sec, with auto ISO so I don’t have to think about settings too much while I’m trying to keep up with a massive shark.
If you do take a camera to Darwin, we’d love to see your whale shark photos! It’s hard for us to visit Darwin for more than a couple of weeks per year, so photos from visiting divers (from years past, too) are a huge boost to our research. You can submit their whale shark photos from the Galapagos to the global database at www.sharkbook.ai.
If you want to learn or improve your underwater photography, I highly recommend Alex Mustard’s book: Underwater Photography Masterclass. It’s a fantastic guide to a rather technical subject!
Are there any operators that work with whale shark scientists?
Scientists don’t work off public dive liveaboards in Galapagos (due to research permit conditions), but some researchers do host educational dive trips. Including me! I’ll lead a shark-focused trip back up to Darwin in July 2023 for Galapagos Shark Diving.
Anything else you’d like to know? Thoughts you’d like to share? Feel free to comment below :)
Simon.
