Dancers of the Deep

In ensemble glides, or solo pirouettes and leaps, Hawaii’s dolphins capture our imagination.

870

Story by Teya Penniman | Photography by Tracy Kraft Leboe

hawaii dolphinsLiving in Hawaii transforms residents into tour guides every time visiting friends and family drop their closed-toed shoes on the lanai. A not-infrequent request: “Where can I swim with dolphins?”

Since ancient times, dolphins have captivated us. Roman coins and Greek myths tell of dolphin rides and rescues. Australia’s aborigines considered dolphins as fishing partners, helping to round up mullet for all. Since the 1940s, trained dolphins have been an entertainment commodity, awing spectators with hoop-leaping, hat-wearing, even picture-painting antics.

Like other swim teams across the country, one Maui club has adopted a dolphin moniker, perhaps with hopes of emulating these master swimmers.

All dolphins are called naia in Hawaiian, but at least eight different species call our waters home. Pacific bottlenose, rough-toothed, spotted, and spinner dolphins are the most common. Telling them apart may be difficult for the untrained eye. Unless you’re doing a dental exam on a rough-toothed dolphin, you aren’t likely to notice the distinctive vertical grooves on its teeth! Patterns in coloration and the presence or absence of spots can help identify which of these smaller cetaceans has just crossed your path.

Unlike porpoises, dolphins have a distinct beak or elongated rostrum. The upturned corners of the dolphin mouth make it easy to imagine a perpetual smile. They are the essence of grace in water: their sinuous, S-shaped curving motions propel them effortlessly through the liquid element. Like us, they play—catching and flicking floating leaves or seaweed with their fins, flukes, or rostrums, dashing to be the first to capture a dropped treasure.

dolphins hawaiiAnother reason to say “Lucky we live Hawaii”: we have the best twirling dolphin in the world. Spinner dolphins do the typical speed jump, leaping above the water as they move forward, but their spectacular aerial acrobatics are unmatched by other species. As the dolphins travel in a slow-moving group, one or more animals will accelerate upward at a sharp angle with a powerful tail thrust. Clearing the water, the dolphin rotates rapidly on its snout-to-tail axis, head pointed skyward, tail towards the water, followed by a headfirst reentry, and lands with a splashy side slap. Spinners have been seen leaping ten feet in the air, completing seven full spins in just a few seconds. Energetic somersaults, tail and head slaps are also part of the aerial repertoire.

Even dolphins have to practice—they aren’t born knowing how to spin. Young spinners, called calves, may be the most active members of a school, but their aerial maneuvers lack the precision and height of their elders, like a toddler taking those first wobbly steps. Scientists have yet to figure out why dolphins spin. Is the reentry splash a form of communication? Does the impact help dislodge remora, a suckerfish attached to their sides? Or perhaps it’s for the sheer fun of it—they do it because they can.

At night, spinner dolphins move offshore to feed on fish and squid. During the day, they rest and socialize in Hawaii’s bays. These clear and protected waters are vital habitat, because at rest, dolphins are more vulnerable to sharks and other predators. During such periods, which last up to five hours, spinners are much quieter and stop emitting sonar. Only half their brain is fully active. Julian Tyne, a Ph.D. student from Australia, is studying the spinners of the Big Island. Tyne says that when they rest, spinners “don’t do aerial displays; they gel together and stay down longer.”

DNA studies indicate that spinner dolphins associate with specific islands; our Maui spinners are genetically distinct from those found along the Kona coast, perhaps making site-specific resting locations critical to their overall wellbeing.

In Hawaii and elsewhere, dolphins have become an economic force for tourist industries that offer close-up-and-personal encounters. A wide range of benefits have been attributed to intimate contact with dolphins, including enhanced wellness, decreased depression and resumption of speech in an autistic child. But resource managers and some dolphin appreciators question whether the interspecies contact is mutually beneficial. Tyne’s research has sparked the interest of local residents, whose anecdotal stories suggest the numbers of dolphins using the bays has dropped dramatically as human interactions have increased over the years.

Most wild encounters are possible because we prefer the same qualities for swimming holes. Hulopoe Bay, on the southern stretch of Lanai, is shielded from the northeasterly trade winds, and its crescent expanse of sandy bottoms and coral gardens delivers hours of easy snorkeling over calm waters. Those same sandy patches and tranquil seas have made it a favorite hangout for a group of spinner dolphins. Sightings there can’t be guaranteed, but they do occur. Signs warn against intentionally approaching within fifty yards, touching, or otherwise harassing the animals, under penalty of federal law, but some people either don’t see the signs or ignore them. And as happens elsewhere, at times the dolphins appear to initiate contact by approaching the swimmer.

Hawaiians have a proverb about the dolphin: He naia, he ia lele, which translates, “It is the naia, a jumping fish”; said of one who leaps to conclusions. Are we like the naia in the proverb, projecting our desires onto wild creatures? Is our presence an unwelcome disturbance during the dolphins’ twenty winks (not forty—they keep one eye open while sleeping)? When dolphins move towards swimmers, do they do so out of a desire to interact with us or are these the sentries of the pod, checking us out for the rest of the group?

The federal agency charged with protecting marine mammals, the National Oceanic and Atmospheric Administration, has recommended a temporary closure of some bays on the Big Island to study the impact of human contact on the dolphins. Tyne’s project is looking at pre- and post-closure dolphin behavior in four bays where dolphins and humans regularly interact. His research uses acoustic devices in the water to record vocalization rates (whistles and echolocation clicking), and digital theodolites (surveying instruments) operated from cliff tops to track movement patterns and document distances between dolphins and humans. The same types of observations will be made after the closures to see whether the dolphins’ behavior changes. Options under consideration by NOAA include no changes to the status quo, establishing minimum distances, regulations on types of human activities, and complete closures of designated areas to commercial and noncommercial activities.

But even the scientists have their moments of exhilaration. Tyne says, “I understand why people get excited about dolphins. Every day is memorable when I’m out on the water and see them,” including the day spinner dolphins cavorted on one side of his boat while two humpback whales surfaced on the other. Ken Norris, who pioneered work on the spinners in Hawaii, noted that the dolphins were “uncommonly welcoming wild animals.”

So unless and until the regulations change, what is our kuleana (responsibility) for the dolphins? Besides the possibility of interrupted rest, dolphins face threats from marine debris, underwater noise, fishery interactions, and marine pollution. One possible answer for our visiting relations is to tell them where they might see dolphins, while also explaining that underwater encounters are most likely to occur while the dolphins are trying to sleep. Learning about their daily cycles and which behaviors indicate they are in a resting state can help minimize disturbance. If we give these enchanting creatures their space and work to reduce other human impacts, we may continue to share our bays and coves with wild dolphins for a very long time.

LEAVE A REPLY

Please enter your comment!
Please enter your name here