Why is Cape Verde Special Underwater?

WHY IS CAPE VERDE SPECIAL UNDERWATER?

When diving to Cape Verde, you shouldn't only think "what species can we see?" These volcanic islands rising in the middle of the Atlantic, approximately 500–600 km off the African coast, form a very special biogeographic area where tropical species, open ocean creatures, and endemic species found only in this region meet in the same waters.

According to current scientific studies, 393 fish species have been recorded in Cape Verde's coastal waters between 0–200 meters. At least 23 of these are endemic coastal fish to Cape Verde. In other words, a small rock fish you might see during a dive could be much more "specific to Cape Verde" than a shark.

1. In April, don't let your eyes stay only underwater

Cape Verde is one of the known important breeding areas for North Atlantic humpback whales (Megaptera novaeangliae). Whales come here not so much to feed, but to mate, give birth, and raise their calves.

The waters around Boa Vista are particularly important in terms of mother-calf pairs. While research generally places the breeding season in Cape Verde between January–May, observations and photo-identification records show a concentration especially in April. The fact that the average peak of photo-ID observations in long-term data falls around April 17th is particularly noteworthy.

Therefore, during our tour from April 17–25, observing the sea while traveling by boat to the dive site could be as important as the dive itself.

If we see a humpback whale, we're not just witnessing a whale "passing by" by chance, but rather witnessing one of the Atlantic's most fascinating migrations in its breeding phase.

2. A shark nursery in the middle of the Atlantic

Cape Verde is also extremely interesting in terms of sharks.

Research conducted in Sal Rei Bay in Boa Vista revealed that it is one of the first scientifically defined multi-species shark nursery areas in Atlantic Africa.

In studies conducted between 2016–2019, more than 6,000 juvenile and young sharks were recorded in the area. Among them:

• Milk shark – Rhizoprionodon acutus
• Scalloped hammerhead – Sphyrna lewini
• Blacktip shark – Carcharhinus limbatus
• Atlantic weasel shark – Paragaleus pectoralis
• Nurse shark – Ginglymostoma cirratum

More recent studies indicate that Sal Rei Bay is used as a breeding or juvenile development area by at least six shark species.

For this reason, seeing a small shark in Cape Verde can sometimes be more scientifically interesting than seeing a large one. Because the animal in front of you could be one of the young residents of the Atlantic's important "shark nursery."

3. Lemon shark: the major predator of shallow waters

One of the noteworthy species expected to be encountered especially in shallow coastal areas of Cape Verde is the lemon shark – Negaprion brevirostris.

Lemon sharks are mostly associated with areas close to shore and shallow waters, and can sometimes be seen in quite shallow waters with sandy bottoms. The presence of this species in Cape Verde is documented by current observations and research.

For this reason, you don't always need to do a deep shark dive to see them. Sometimes one of Cape Verde's most impressive predators might appear just a few meters deep.

4. The blue of the open sea: blue shark

Unlike coastal species, the blue shark – Prionace glauca – is a true open ocean wanderer.

For this reason, encountering a blue shark is different from a shark encounter in a classic reef dive. Here, the environment itself is part of the experience: hundreds, even thousands of meters of water below you in the open Atlantic.

Cape Verde's location is interesting in this respect. The islands form a system where coastal habitats and oceanic habitats are very close to each other.

5. Cape Verde has its own fish

While looking at large creatures, you shouldn't miss the small fish.

According to the latest scientific inventory, there are 23 endemic fish species on Cape Verde's coasts. These are species whose natural distribution is essentially limited to this archipelago in the world.

Some of the endemics that can be particularly sought during dives:

• Cape Verde chromis – Chromis lubbocki
• Cape Verde damselfish – Similiparma hermani
• Sal blenny – Parablennius salensis
• Cape Verde blenny – Microlipophrys caboverdensis
• Scartella caboverdiana
• Gobius salamansa
• Diplodus fasciatus
• Diplodus lineatus
• Diplodus prayensis

For this reason, while searching for "the big one" from a photographic perspective, it's worth not neglecting the few-centimeter fish on the rocks.

Because we can see a shark in many places in the Atlantic; for Chromis lubbocki, we're at the right address.

6. Bad news for nudibranch enthusiasts: you might not be able to lift your head from the rocks

Cape Verde is noteworthy not only for fish endemism but also for small invertebrates.

In a recent study conducted on Sal, Boa Vista and São Vicente, 27 Heterobranchia species were identified, and approximately 44% of the sampled species were reported to be endemic to Cape Verde. The study also identified a new record for the archipelago and a species that might be new to science.

Therefore, for someone doing macro diving in Cape Verde, a few-centimeter sea hare on the rocks can have as much scientific value as a large fish in the open water.

This is not a place where people say "we didn't see any sharks, the dive was a waste."

7. Oceanic manta: Cape Verde could be a stopover point

Oceanic manta – Mobula birostris – is also recorded around Cape Verde.

Research conducted between 2015–2019 and results obtained from satellite transmitters attached to 11 individuals showed that oceanic mantas are regularly found in the archipelago. However, the low rate of resighting the same individuals raises an interesting possibility:

Cape Verde may be one of the "stopover points" in a much larger Atlantic migration corridor rather than a center where mantas permanently reside.

In other words, a manta we encounter while diving could be hundreds of kilometers away a few weeks later.

8. Caretta caretta – islands of global importance

Cape Verde's beaches have global significance for Caretta caretta.

The archipelago, particularly Boa Vista and Maio, hosts one of the world's largest Caretta nesting populations. The fact that more than 14,000 nests were recorded in just one year during detailed studies conducted in Maio gives an idea of the population's size.

What's even more interesting is that Cape Verde is not home only to Caretta. In recent years, nesting attempts by green sea turtles (Chelonia mydas), olive ridley sea turtles (Lepidochelys olivacea), and hawksbill sea turtles (Eretmochelys imbricata) have been documented.

Therefore, it is worthwhile to pay particular attention to the species of sea turtle we encounter underwater.

9. Cape Verde is actually a "biogeographic crossroads"

One of the key features that makes Cape Verde's underwater environment special is its geographic location.

The archipelago is isolated from African shores but lies under the influence of tropical East Atlantic fauna. At the same time, it is related to the migration routes of open ocean species. Long-term isolation has allowed some small coastal fish to differentiate here.

As a result, on the same dive trip:

humpback whales,

sharks,

oceanic manta,

sea turtles,

open ocean pelagics

and a few centimeter-long endemic fish found only in Cape Verde are likely to be encountered.

For this reason, viewing Cape Verde merely as "an Atlantic island where shark diving is done" would be incomplete.

This is a small natural laboratory where open ocean migrations meet island endemism in the same underwater geography.

A SMALL NOTE FOR THE DIVER

When diving in Cape Verde, it is worth looking at three different places:

Look at the open blue: for sharks, mantas, and other pelagics.

Look at the rocks: for endemic fish and nudibranchs.

Continue looking into the water when you get back on the boat: because in April, the largest creature we search for underwater, the humpback whale, will most likely be seen above the water.

Diving in Cape Verde is a bit like this:

Sometimes the most interesting creature is 15 meters long.

Sometimes it's 3 centimeters.

Sources

Malaquias, M. A. E., Turani, M., Lopes, E., & Cervera, J. L. (2025). The Heterobranchia gastropods from the Cabo Verde Islands (NE Atlantic): A hot-spot of endemism. Regional Studies in Marine Science, 86, 104193. https://doi.org/10.1016/j.rsma.2025.104193

Marco, A., Abella, E., Liria-Loza, A., Martins, S., López, O., Jiménez-Bordón, S., Medina, M., Oujo, C., Gaona, P., Godley, B. J., & López-Jurado, L. F. (2012). Abundance and exploitation of loggerhead turtles nesting in Boa Vista island, Cape Verde: The only substantial rookery in the eastern Atlantic. Animal Conservation, 15(4), 351–360. https://doi.org/10.1111/j.1469-1795.2012.00547.x

Rosa, R., Nunes, E., Pissarra, V., Santos, C. P., Varela, J., Baptista, M., Castro, J., Paula, J. R., Repolho, T., Marques, T. A., Freitas, R., & Frazão Santos, C. (2023). Evidence for the first multi-species shark nursery area in Atlantic Africa (Boa Vista Island, Cabo Verde). Frontiers in Marine Science, 10, 1077748. https://doi.org/10.3389/fmars.2023.1077748

Sousa-Guedes, D., Marco, A., Neves, E., Medina, M., Taxonera, A., Fairweather, K., Queiruga, A., Veiga, J., Patino-Martinez, J., Alírio, J., Bessa, F., et al. (2025). How vulnerable are the nesting sites of loggerhead turtles in Cabo Verde? Regional Environmental Change, 25, 39.

Whiting, A., Garzon, F., Monteiro, Z. L., et al. (2026). Diversity, abundance and distribution of sharks in a multispecies nursery area in the Eastern Central Atlantic. Aquatic Conservation: Marine and Freshwater Ecosystems, 36(4), e70370.