Wild dolphins are delightful and terrifying.

Yes, they are curious, intelligent creatures, renowned for their friendliness to humans, and certainly they are beautiful with their slick silver fins and swooping swimming skills. But getting up close and personal with these massive animals isn’t recommended. It’s not good for them and an encounter may not end well for you either.

Believe me, I’ve had lots of cause to consider dolphins. Every week, I paddle out on the Sarasota Bay, hoping to spot pods of them, and usually I do. But because I’m balancing precariously on a plank and they are masters of this liquid habitat—and because they can weigh up to six times what I do—when I see their silver fins or catch a brief glimpse of them diving by, I just stop and relish the awe they inspire.

It would be nice to befriend a dolphin perhaps, but it’s illegal to try in the United States. The US Marine Mammal Protection Act of 1972 prohibits feeding or otherwise interacting with wild dolphins and other marine mammals. And it also seems very scary, for me certainly, but maybe also for the sea creatures.

Despite the ancient mythology about our mutual admiration, dating back to 77 CE when Pliny the Elder published an account of a friendship between a boy and a dolphin, there is scientific evidence that they can be disturbed by human contact.

Reuters Dolphin and calf.

We already know that boat traffic affects humpback dolphins’ acoustic behavior in Australia (pdf), prompting increased whistling between pods that include mothers and calfs. This indicates that mothers and their young are most disturbed by the human traffic and need to do more whistling to reestablish contact than they do when humans aren’t transiting their territory.

Wild dolphin tourism in Australia and New Zealand has also been shown to lead to harassment, stress, injury and death for dolphins, as well as human injuries.

Bottlenose dolphin tourism in Florida (pdf) has likewise proven problematic, with interaction between species putting both the sea creatures and the people at risk of injury and disease. The dolphins were attracted to people who fed them from boats but they then risked injury from the vessels’ propellers or from boat hits, as well as from aggressive individuals. Dolphins also occasionally got aggressive with people, and touching them made humans vulnerable to disease just as human touch threatened the health of the bottlenose beasts.

In waters off of West Africa, the rare Atlantic humpback dolphin is now endangered because of human activities. The biggest threat to the dolphins is reportedly bycatch, when they are unintentionally entangled in fishing gear. Port construction has also impacted the dolphins’ habitat.

In fact, in 2005, a United Nations global survey found that more than 70% of the world’s 40 dolphin species were endangered by snare fishing nets. Many more were threatened by pollution, military sonar, habitat destruction, and intentional hunting. The Michigan State University Animal Legal and Historical Center noted in 2017 that the major threat to dolphins’ survival is humans.

Our trash is also a problem. The seas are awash in plastics that make their way into the bellies of marine creatures. In April, a stranded dolphin washed up very sick on a Florida beach and was euthanized. It had two plastic bags and a piece of a balloon in its stomach. Whether the detritus caused its illness is undetermined but marine scientists called the bits of litter a “significant finding.”

Dolphin dangers

We just can’t get enough of a good thing, and aren’t satisfied admiring dolphins from afar. It is illegal in many places around the world to harass these animals. But humans aren’t about to stop boating or fishing or trying to swim with dolphins at tourist spots and that is not always great for the sea creatures or people.

Reuters/Jason Reed Surfers watch dolphins ride the waves off Sydney’s Palm Beach.

It is true that around the world lone sociable dolphins have been found to seek human interactions. However, these dolphins are few in number, are alienated from other dolphins, and their engagements with people aren’t always positive. Of the 29 well-studied lone sociable dolphins globally, 13 exhibited “misdirected sexual behavior towards humans, buoys, and/or vessels.” Some abducted people, dragging them far from the shore and preventing their return. And two-thirds were overtly aggressive with humans, resulting in ruptured spleens, broken ribs, unconsciousness, and even death, according to an essay in Aeon by Justin Gregg, a marine scientist, dolphin specialist, and author of the 2013 book Are Dolphins Really Smart?

Gregg notes too that all the evidence of dolphins saving humans at sea—and there are such stories—has been anecdotal. He doubts that people traumatized by their ocean experiences are necessarily recalling correctly when they claim a pod of dolphins saved them from a shark, say, making these tales unreliable from a scientific perspective. “Since it is well‑known that dolphins provide this kind of altruistic support to each other (also known as epimeletic behavior), the idea that dolphins can and do rescue humans in these ways is entirely possible, if not likely. But there is not enough evidence to evaluate the true nature of these encounters,” the dolphin expert writes.

Just like us, kind of

So why all the hype about our special bond with dolphins? Well, because we humans feel a deep affinity for them and like to think that they resemble us, only much bigger and better at swimming. They have big brains, like people, a capacity for language, seem to have sex for pleasure, suffer from dementia, grieve for their dead, and some species do hang out in shallow waters near us.

Some dolphins have even turned to humans for help, as seen in this simultaneously heartbreaking and heartwarming video of a dolphin seeking a divers’ assistance in removing a fish hook and line caught in its fin in waters off of Hawaii that was part of the 2016 TV series “Conversations with Dolphins.”

Whether the affection is mutual—when we’re not bribing them with food or saving them from humanity’s dangers—isn’t clear. Maybe dolphins are just generally empathetic and altruistic, as Gregg suggests.

Just this week, for example, dolphins in Florida put up such a fuss when they saw a doberman pinscher struggling to paddle after jumping in a canal that they alerted humans to the lost dog’s presence. The dog was saved, and this is not the only such story. But humans write the narratives about these situations and we can’t say how the dolphins tell these tales in their language of clicks and whistles, if at all.

It does seem that dolphins are interested in humans and that they are even willing to cooperate with us, in the wild. For example, in Laguna, Brazil, fishermen and dolphins appear to work together. Dolphins quickly herd large schools of mullet towards the people, who wait with nets in the shallows, and once the the dolphins begin to dive, the fishermen throw their nets in, disorienting the fish, which benefits the dolphins as well.

Reuters/Mariana Bazo Dolphins dive by a beach in Peru.

Captive dolphins have even been trained to dive on behalf of the military as part of the US Marine Mammal Program. They hunt for mines, protect human divers, who are less sensitive to the presence of these weapons, and retrieve objects. The Navy says it has never trained dolphins for attack missions, however.

There is no question then that dolphins are awesome and capable and that our adoration of these creatures is merited. But there’s also little doubt that the same admiration that has helped to protect dolphins from humanity’s voracious appetites in some places around the world, has also ended up creating problems for the beautiful beasts.

So if you are lucky enough to spot a dolphin pod in the wild, please do not disturb. Your respectful distance will signal the depth of your friendship.