Dolphins are some of the most intelligent animals on earth that can be found in a wide range of the world’s oceans.
They typically prefer warmer, tropical waters but also inhabit the icy waters of Antarctica to make sure of the abundance of food there.
Today, we’re going to take a closer look at the dolphin species as a whole as well as their populations to find out are dolphins endangered?
No, the dolphin species as a whole is not endangered. However, according to the IUCN Red List of Threatened Species, out of 41 dolphin species, five species and six subspecies are endangered.
Are Dolphins Actually Endangered?
The dolphin species as a whole have a conservation status of “Not Extinct”, but there are some species of dolphin that are endangered and facing potential extinction in the near future.
When a species is considered endangered, they either fall into the Critically Endangered, Endangered, or Vulnerable category.
Sadly dolphins face a lot of the same threats that many marine species face, which can lead to their numbers declining rapidly.
Habitat degradation, ship strikes, bycatch, and pollution are just a few threats that the dolphin species face on a daily basis.
So which species of dolphin are currently endangered?
Atlantic Humpback Dolphin
The Atlantic humpback dolphin is currently considered “critically endangered” as their populations are rapidly declining and it’s thought that there are less than 1500 individuals left in the wild.
The biggest threat to this species of dolphin is accidental bycatch by fisheries since they are found in the shallow waters off the coast of West Africa, they’re extremely vulnerable to gillnets by local fishermen.
Atlantic humpback dolphins are also susceptible to the “marine bushmeat” treatment as well as pollution which has impacted their numbers drastically.
Amazon River Dolphin
Also known as the “Pink river dolphin”, this beautiful species is endangered as one of its main threats to survival is deliberate killing for predator control and fish bait.
In Brazil, poachers illegally kill these dolphins and use their fatty blubber as bait to catch other fish.
To help stop illegal hunting and protect the dolphins, the Brazilian government introduced a moratorium on catching piracatinga from July 2015 to July 2021.
Baiji Dolphin
The Baiji dolphin is currently considered “critically endangered” but will soon be considered extinct, making this the first dolphin species to be driven to extinction by humans.
The last documented sighting of the Baiji dolphin was in 2002. Since then, only unconfirmed sightings have been made by students and local fishermen have been reported.
Found only in the Yangtze River in China, these dolphins were frequently under threat from accidental bycatch from fisheries.
Maui Dolphin
The Maui dolphin is also considered “critically endangered” as there are only 55 known Maui dolphins left in the wild.
This species is known as the smallest dolphin species in the world. They are slow breeders with mothers only having calves every 2-3 years and they don’t reach sexual maturity until they are between 7-9 years old.
Again the dolphin’s biggest threat is from accidental bycatch by fisheries which can devastate the population.
South Asian River Dolphin
The South Asian River dolphin is divided into two subspecies (the Ganges river dolphin and the Indus river dolphin), it’s estimated that the total population is less than 5000.
The South Asian river dolphins’ biggest threat is surprisingly not accidental bycatch, but instead water development projects such as dams and irrigation barrages.
As a result, populations are fragmented and habitats are reduced, the IUCN labels this dolphin species as “endangered.”
Dolphin Threats
No matter where each species calls its home, in oceans or freshwater they still face numerous threats that can diminish their populations quickly.
Below I’ve listed some of the threats dolphins are faced with, whether it be directly through means such as poaching or indirectly through climate change or pollution.
Bycatch
Bycatch is the result of dolphins being caught up or entangled in transparent fishing lines or nets which can quickly suffocate them and cause death.
Since dolphins breathe through their lungs and not gills, they are required to surface every once in a while in order to breathe.
According to a 2019 review by the NOAA (National Oceanic and Atmospheric Administration), many critically endangered small cetaceans are threatened by bycatch.
Pollution
Noise pollution and chemical pollution pose big threats to many dolphin species. Dolphins depend on pulsed and tonal sounds for communication, navigating, and finding food.
Therefore underwater noise caused by boat traffic, sonar, and underwater construction can make it much harder for dolphins to do all of these things.
Ocean pollution from chemical spills can result in disease among large populations of dolphins, which typically leads to adverse health effects, reproductive failure, and even death.
In 2010, the Deepwater Horizon oil spill caused 4.9 million barrels of oil to leak into the Gulf of Mexico, the largest recorded marine oil spill in world history.
Subsequent research concluded that stranded dolphins in the area were 20% more likely to have died from bacterial pneumonia and 26% more likely to have died from the adrenal crisis than dolphins from unaffected regions.
Climate Change
Climate change is affecting so many different animals and having a huge impact on their habitats.
For example, polar bears rely on the sea ice in order to travel and hunt, but each year the ice is melting more and more, forcing them inland to search for food and ultimately leading to many starving to death.
Rising water levels, ocean acidification, and declines in prey species are all serious threats to dolphins.
Marine mammal die-offs have been linked to poisonous algae blooms such as red tide which results from warming oceans.
Dolphins can become exposed to these biotoxins through the air or by eating contaminated prey, leading to health conditions.
Hunting
Dolphins and other small cetaceans have been found to have dangerously high mercury levels, but they are still being actively hunted in some parts of the world.
In some regions of Japan, dolphins are hunted for their meat, blubber, and organs which has been the subject of controversy in the past.
But dolphin hunting doesn’t just happen in Japan. In the Mediterranean, dolphins were seen as a pest species by fishing organizations which led to national laws permitting the hunting of these animals.
It’s estimated that over 6,700 dolphins were killed in a ten-year period from 1927 to 1937, which Italian zoologists believe may have had a significant effect on local dolphin populations.
Habitat Loss
As our human population begins to grow, so do man-made structures such as dams and other waterfront developments.
This pushed dolphins and other marine life out of their natural habitats and given that dolphins typically reside in shallow coastal waters they can be affected by the construction and contaminants.
For example, the endangered Indus river dolphin subspecies which once roamed throughout 2000 miles of water within the Indus river system in Asia, lost 80% of its range due to large-scale irrigation projects.
Final Thoughts
So, are dolphins endangered? No, not as a whole. However, 5 of the total 41 species of dolphin are currently endangered and risk extinction in the near future.
It is such a shame that an intelligent species like the dolphin can be pushed to near extinction by human activities but it’s sadly the reality we are faced with.
It’s not only dolphins that face such threats, lots of marine wildlife face similar threats with pollution, bycatch, and overfishing being top contributors to the downfall of so many marine animals.
Hopefully, you’ve enjoyed this post today and have learned something new today about why some species of dolphins are endangered.
Thanks for taking the time to read this post and feel free to stick around to learn more about dolphins and other marine wildlife.
Hi, I’m George – the founder of MarinePatch. I created this blog as marine wildlife has been my passion for many years. I’ve spent over a decade in the marine wildlife industry and spent years out in the field conducting research. In today’s modern world, an online blog is the best place for me to share my findings and reach as many people as possible to help educate and inspire others. Enjoy your time here and you’re welcome back anytime!