Males have two slits, one for the penis and one further behind for the anus.
While Females have one genital slit, housing the vagina and the anus, with a mammary slit on either side.

Anatomy in male and female dolphin (www.mmapl.ucsc.edu)

Couples for Life?

Noooo! Dolphins are polygamous, meaning they have more than one mate. Plus, there is no actual mating season for dolphins, which means they can mate throughout the whole year. However, ninety percent of their mating activity is foreplay. On the other hand, intercourse only takes seconds (Wells et al.,1999).

Sexual Maturity

The age of sexual maturity varies by species and gender, but, in general, males become sexually mature between 8 and 14 years of age. Females become sexually mature a little sooner, around 5 to 13 years of age (Orbach, D et al. 2019).

Male dolphins often appear to coerce females into sex.

So, it can be difficult to tell what a female really wants in a mating situation (Scott et al., 2005). Sometimes, on our tours, we can see many males harassing a single female.

David Rodrigues | Common dolphins underwater

Many Male Dolphins Are Bisexual?

Upon reaching sexual maturity, males form a group of young males where there is a lot of homosexual activity. Some even say they can establish couples for life. For bottlenose dolphins, we can say that they have periods of bisexuality combined with periods of exclusive homosexuality. From the age of 20-25, they become robust mating partners for reproduction. (Byne, 2000).

Engage in Courtship

Typically, males have to catch the attention of females in various ways. So they put on an acrobatic show, fight with other males, and show their strength and dexterity. Some studies also point out that sometimes males arrange “gifts” for females.

And… How do dolphins mate?

Dolphins do not have a breeding season; reproduction occurs at any time of the year. To reproduce, dolphins must contact the belly to fit their genitals.

Álvaro Palácios | Bottlenose dolphin in São Miguel island

Pregnancy

Duration and Development

Depending on the species, dolphins are pregnant between nine and seventeen months. For instance, orcas’ gestation is around seventeen months. Can you imagine?

Birth

When it comes time to give birth, females tend to band together to help the mother give birth. While in other species, the mother tends to isolate herself to have her offspring in a calmer and more relaxed environment.

Calves are usually born tail first and the umbilical cord breaks during delivery.

Nursing

Dolphins with calves produce milk in their mammary glands. The milk is very high in fat and contains colostrum. Colostrum provides antibodies that help protect the calf against infection during those critical first months of life (Eichelberger, L et al. 1940).

David Rodrigues | A baby and an adult Risso's dolphins swimming together — David Rodrigues | A baby and an adult Risso’s dolphins swimming together

Would you like to know the best times for whale watching?

Take a look at our whale watching calendar and plan your next adventure! Don’t miss the chance to spot these majestic creatures in Azorean waters. 🐋 🌊

What About the Baby Dolphins?

How to Recognize a Newborn

We can get an approximate idea of how old a baby is by looking at the dorsal fin and fluke. Indeed, it is thought that the dorsal fin stiffens within a few hours. The tail flukes seem to take a bit longer. Furthermore, when babies are born, they have lighter-colored bands spanning their midsection. These are called fetal bands and are caused by being scrunched up in the mother’s womb. These bands will slough off after multiple weeks (Wells 1999).

Behavior and Development

A baby dolphin swims in a position next to its mother called the echelon position. The baby swims in this position to catch mom’s slipstream, allowing the calf to work less complicated to keep up with its mother. They nurse, on average, a minimum of one or two years but have been observed nursing up to four and a half years (Wells 1999).

Babies are entirely dependent on the females for more than 2 years for breastfeeding (depending on the species). Then, the calves stay close to their mothers for around 5/6 years.

Normally, females give birth to just one baby each time every 3/5 years.

David Rodrigues | Spotted dolphins in São Miguel island during our whale and dolphin watching trips

Family Structure

Females never leave groups, thus creating families with several generations of females. Males, on the other hand, when they reach sexual maturity, leave the groups and create a group of young males. Only when they reach the age to reproduce, do they join females from other groups so that there is no cross between animals of the same family?

References

Byne, W. (2000). Biological Exuberance: Animal Homosexuality and Natural Diversity. JAMA: The Journal of the American Medical Association, 283(16), 2170–2170.
Orbach, Dara & Rattan, Shruti & Hogan, M. & Crosby, Alfred & Brennan, Patricia. (2019). Biomechanical Properties of Female Dolphin Reproductive Tissue. Acta Biomaterialia. 86.
Scott, Erin & Mann, Janet & Watson-Capps, Jana & Sargeant, Brooke & Connor, Richard. (2005). Aggression in bottlenose dolphins: Evidence for sexual coercion, male-male competition, and female tolerance through analysis of tooth-rake marks and behaviour. Behaviour. 142. 21-44.
Wells, R. S., and M. D. Scott. (1999). Bottlenose dolphin Tursiops truncatus (Montagu, 1821). Pages 137 -182 in S. H. Ridgway and R. J. Harrison, eds. Handbook of marine mammals: The second book of dolphins and porpoises. Academic Press, New York Academic Press, New York, NY.

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Impactful & unforgetable experiences

Browse all the outstanding experiences you can live in the Azores

Whale Watching

Lying in the middle of the mystical Atlantic Ocean, the wonderful Azores islands are a permanent home or point of passage for more than a third of the entire world’s whale and dolphin species.
Dive into this lifetime adventure with ancestral creatures where science and emotion come together at their highest level!
This may be the best place on earth to observe these magnificent animals.

Jeep Tours

Feel the rush, surprise, and emotion in an all-terrain vehicle, this adventure will take you to the core of secrets. We will take you where nobody has ever reached before. Experience moments of adrenaline in our jeep tours. The adventure through the interior of the islands will begin!
The trips are made in 4×4 vehicles properly equipped, capable of taking you to places little explored. It is intended for those who want to discover new perspectives and unusual scenarios on the Azores Islands in a more adventurous way. We pass on secondary roads, which are not usually found on the usual tourist routes. They are narrow paths, dirt paths, called “canadas” in Azorean, and are mostly used by farmers.

Kayaking & SUP

Find solace in listening to the birds chirping and enjoy the peacefulness of the moment, and make sure you capture it with your camera this unforgettable experience.
Sete Cidades is a volcanic complex where you can visit several lakes. Inside one of the craters, you can find two lakes, known as Lagoa Verde (green lake) and Lagoa Azul (blue lake), that feature in a legendary love legend about the lake’s creation. This special place was elected as one of the country’s seven natural wonders and once you are there, you will definitely understand why.
The contrast of colors between the two mysterious lakes is mesmerizing, and being on the water, in the middle of the volcanic crater, will give you a different perspective of the high green cliffs around.

Canyoning

The boldest and most unique adventure! Heading through the natural landscape you will be able to enjoy some adrenaline-fueled activities. Wet, wild, and absolutely unforgettable.
This experience involves trekking through river gorges, around pools, or even behind waterfalls.
Canyoners navigate down waterways by abseiling down waterfalls, clambering over rocks, or jumping into water rock pools. You will get wet for sure, even with an exposure suit, but this is not too bad with the relatively warm climate of the Azores.

Van Tours

Take a seat in the emotion sector, stop wherever you want and where your curiosity demands it. Taste, observe, and treasure the entire originality of this Atlantic paradise.
If you want to get to know the island of São Miguel more peacefully, without the worry of renting a car, opt for more comfort, on a pleasant van ride. Make the most of your vacation and get away from the city.
This way, you are guaranteed to know the main points of interest, but also those you will not find in travel guides. This is perhaps the best choice for those looking for convenience and security.

Hiking Tours

From lush green vegetation to a great variety of wildlife, enjoy heaven after a long ramble with otherworldly vistas.
Enjoy your holidays in the Azores walking through the beautiful landscapes of volcanic origin. Breathe fresh air and contemplate all the diversity of fauna and flora you will find.
You can start the day feeling the nature among mountains, enjoy more than one lagoon on the island of São Miguel, and finally, to end the day in a perfect way, take a boat trip to see the sunset.

Bike Tours

In order to discover São Miguel island and stay active, cycling is definitely the way to go!
At Sete Cidades volcanic complex, have one of your best bike adventures! Indeed, we are not taking you to a random place. We are talking here about one of the Seven elected wonders of all of Portugal.
This is where our awesome bike adventures take place and we can tell that we love to take our guests there!

Coasteering

Here, you can explore the geography of the giant rocky cliffs climbing through the sky and how the pounding waves smooth the coastline. Coasteering is an exhilarating experience combining rock and water activity with coastal landscapes. It was originated as a combination of mountaineering and orienteering.