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INTRODUCTION
In 2016, SeaWorld announced that it would end its orca-breeding program after facing mounting criticism from
scientists and the public over its poor treatment of captive orcas (Howard, 2016). Since this announcement, however,
the company has continued to breed bottlenose and Pacic white-sided dolphins—the orca’s smaller cousins—and
house them in small, concrete tanks, as well as exploiting them in archaic, circus-style performances and interactive
programs in which they’re touched, grabbed, and stood on by trainers.
In November 2018, a veterinarian observed the captive dolphins held at the SeaWorld parks in San Diego,
San Antonio, and Orlando. Evidence obtained from those observations revealed that the well-being of captive
dolphins at the parks is severely compromised by the conditions in which they’re forced to live. is includes an
astonishing number of dolphins—140—conned to just seven tanks at four SeaWorld–owned theme parks in the
Unites States.i is report provides a glimpse into the miserable lives of these exploited animals, who endure routine
physical, psychological, and social stress and at times sustain painful injuries as a result.
PEOPLE FOR THE ETHICAL TREATMENT OF ANIMALS | 1
DOLPHIN EXPLOITATION AND
SUFFERING AT SEAWORLD PARKS
Heather D. Rally, D.V.M.
Supervising Veterinarian, PETA Foundation
Toni Froho, Ph.D.
Behavioral Biologist and Research Director, TerraMar Research
JUNE 5, 2019
© dreamstime.com/Paul Brewster
GENERAL CONDITIONS
Captive dolphins at SeaWorld are housed in severely crowded, extremely shallow, small enclosures that are spatially,
acoustically, and visually unnatural to the species. Most have barren concrete walls with bright, reective surfaces that
prioritize maximum visibility and accessibility of dolphins for park visitors over consideration of the animals’ health
and welfare. For example, in SeaWorld’s shallow petting pools, members of the public are permitted direct access to
the edge of the pool and are frequently observed harassing the dolphins by splashing and submerging their arms and
hands in an attempt to grab and touch the animals. e tanks are devoid of sucient depth and any natural features,
hiding places, or variability that would allow the dolphins to take refuge from conspecics or the public, creating
an environment of inescapable, routine stress (Froho & Beko, 2018).
Conning captive wild animals to small, barren, crowded enclosures causes them physical harm and trauma and can lead
to illness and premature death. Studies have shown that far-ranging carnivores, such as dolphins, who would routinely
travel long distances in nature, are acutely susceptible to suering when conned to enclosures—like those
at SeaWorld—that are just a minuscule fraction of the size of their natural home range (Clubb & Mason, 2003).
An extremely small tank at SeaWorld Orlando labeled the “Dolphin Nursery” held at least 11 full-grown adult
bottlenose dolphins. is tank, which is shallow in order to maximize visibility of the animals for park visitors, contains
less than one third of the water that an Olympic-sized swimming pool does. Such a space isn’t adequate to house a single
adult bottlenose dolphin, let alone nearly a dozen of these deep-diving, far-ranging, socially complex mammals.
Whether caught in the wild or bred in captivity, dolphins are wild animals who are biologically driven and highly
motivated to engage in specic natural behavior that helps them thrive in the ocean. is behavior includes
swimming distances of up to 60 miles per day, diving to depths of nearly 1,500 feet, and maintaining dynamic
relationships within a large social network (Klatsky, Wells, & Sweeney, 2007; Mann, Connor, Tyack, & Whitehead,
2000). Yet dolphins at SeaWorld are conned to constrained and injurious environments that are lacking in natural
variability and features variability, treated with chemicals, and physically restrictive, with depths that are often only
marginally greater than the legally required minimum of 6 feet (USDA, 2017), which is wholly inadequate and less
than the length of their own bodies.
ACOUSTIC STRESS
Dolphins at SeaWorld parks are housed in conditions that exacerbate the impact of unnatural and anthropogenic noise
on them. Acoustic stress is a serious welfare concern for captive dolphins, who would use their sophisticated acoustic
systems to communicate, navigate, hunt, and visualize their environment in the wild with astonishing acuity. eir aural
anatomy and physiology is highly complex and exceptionally sensitive to sources of sound and vibration. e dolphin
tanks at SeaWorld parks—with their parallel concrete walls, metal gates and latches, and mechanical ltration plants and
pumps—create an environment that potentiates anthropogenic noise, vibrations, and reverberations from both inside
and outside the tank (Couquiaud, 2005).
Additionally, at SeaWorld, dolphins are typically conned either to petting pools, in which they’re forced to interact with
park visitors, or to performance pools, in which they’re forced to perform for audiences, both of which present unique
noise insults. Park visitors have been observed tapping, knocking, and even banging on underwater-viewing tank glass
at SeaWorld’s dolphin petting pools in an attempt to attract the animals’ attention. Because of the physical properties of
sound propagation in water, such seemingly innocuous behavior can translate into intrusive noise that routinely assaults
the animals’ hearing inside the tanks, creating an acoustic insult that is likely to cause chronic stress. Dolphins in shows
were also routinely exposed to large, raucous crowds and loud, amplied music projected from speakers surrounding
PEOPLE FOR THE ETHICAL TREATMENT OF ANIMALS | 2
their tanks. ese noise levels in the air would also be expected to aect dolphins, who must spend signicantly more
time with their heads above the water for shows than they would naturally in the wild (Rose & Parsons, 2019).
A growing body of research has found that exposure to excessive or unnatural levels of noise can aect a number
of health and welfare parameters in cetaceans, including immune suppression, increased aggression, and premature
hearing loss (Couquiaud, 2005). Indeed, captive dolphins who are exposed to acoustic insults are known to
demonstrate physiological and behavioral indications of stress, such as an increase in circulating stress hormones
and a refusal to perform or eat. Captive dolphins have even died because of severe acoustic disturbances (Couquiaud,
2005; Monreal-Pawlowsky et al., 2017).
SOCIAL STRESS
Another factor that is known to have a dramatic eect on captive dolphins’ health and well-being is acute or chronic
social stress. Dolphins are highly social, with an impressive capacity for emotion as well as self- and social-awareness.
eir complex social networks include intimate, sometimes lifelong relationships between individuals and dynamic
aliations among groups ranging over wide areas (Waples & Gales, 2002). Yet dolphins at SeaWorld continue to be
housed in articial social groups. Given the cramped living conditions that they’re chronically kept in, it’s no surprise
that aggression among them appears to be commonplace.
e dolphins used in theatrical performances and human-interaction programs are required to perform tricks for
a food reward of dead sh. During a performance at the San Diego location, two dolphins aggressively chased,
tail-swiped, and bit at each other while trainers encouraged them to pose for a photograph with members of the
public and allowed the park visitors to feed them by hand. is incident not only placed the public in danger but also
exposed the fact that SeaWorld’s practice of baiting captive dolphins to perform tricks for food rewards contributes
to heightened aggression and social tension among them.
Indeed, many of the dolphins at SeaWorld were observed with rake mark injuries and scars, which are parallel,
linear wounds sustained when dolphins are bitten by conspecics while swimming. In the wild, aggressive encounters
between dolphins can dissipate when a subordinate animal retreats from an aggressor, but in captivity, dolphins
can’t escape from aggressive attacks. is, coupled with the fact that captive dolphins often demonstrate unnaturally
heightened levels of aggression in captivity as a result of stress or deprivation, results in excessive raking incidents.
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Indeed, at SeaWorld parks, some of the dolphins were observed with extensive rake mark lesions across their entire
bodies, supporting the conclusion that aggression is commonplace among them.
Dolphins’ skin is their immune system’s rst line of defense, and the routine compromise of this important defensive
barrier can have serious health implications. Extensive or repeated breaks in the skin not only are painful but also
expose the tissues and blood vessels to environmental pathogens, increasing the risk of localized and even systemic
infection. Furthermore, dolphins, as a highly social species, are particularly vulnerable to the emotional impact of
social alienation and tension, which can result from resource competition, severe crowding, the transfer of animals
between tanks or facilities, and other management decisions that aect the social stability within a captive dolphin
population. Subordination, alienation, and disrupted social group dynamics have been implicated in both illnesses
and deaths of captive dolphins (Waples & Gales, 2002).
DENTAL DISEASE
Numerous dolphins at SeaWorld parks were observed with dental trauma, some with cases so severe that every one of their
approximately 100 conical teeth were completely missing above the gum line. Dental trauma is commonly observed in
captive wild animals who develop self-injurious abnormal behavior as a result of chronic behavioral deprivation or trauma
(Morgan & Tromborg, 2007). Severe cases are common in captive marine mammals who are particularly prone to tooth
damage associated with aberrant, self-injurious behavior such as gnawing on hard surfaces in their tanks or aggressively
“jaw popping” at conspecics, sometimes through metal separation gates (Rose & Parsons, 2019).
Severe or sudden dental trauma, such as a fracture, can expose
the living pulp cavity within the tooth. Dental trauma of this
nature not only is painful but also predisposes animals to
infection (Holmstrom, 2018). Indeed, it is well documented
that captive orcas, who are well known for having high rates
of dental trauma, routinely develop repeated infections of
traumatized teeth that require regular antibiotic therapy to
prevent local and systemic infection (Cornell, 2011; Jett, Visser,
Ventre, Waltz, & Loch, 2017). In addition to the direct health
risks that dental trauma poses, the routine or inappropriate
use of antibiotics can promote antibacterial resistance, creating
a risk of more severe and potentially untreatable infections in
the future. Notably, numerous systemic diseases that are linked
to dental infections can be life-threatening, and captive
dolphins routinely die prematurely of infectious diseases
in marine parks despite access to around-the-clock veterinary
care (Tryland, Larsen, & Nymo, 2018).
CIRCUS TRICKS AND LESIONS
Dolphins conned to show tanks are surrounded by stadiums full of people and required to perform up to twice a day.
ey engage in a variety of circus-style tricks that are devoid of both biological signicance to them and educational value
to the public, including allowing trainers to “surf” on their back or stand on the beak-like part of their mouth called the
rostrum. ese tricks are completely unnatural and send confusing messages to the public about normal dolphin behavior
and safe human-dolphin interactions.
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Furthermore, countless dolphins at SeaWorld parks were observed with active wounds on the tip of the rostrum or scars
indicating pre-existing wounds. It is common for captive dolphins to injure their rostrum while conned to a restrictive
environment in which they’re surrounded by unnaturally hard surfaces, such as concrete and metal, that easily cause trauma
to the skin. Despite the obvious vulnerability of the rostrum to injury and the evidence of existing wounds on numerous
dolphins, SeaWorld continues to force these animals to perform demeaning tricks that could cause skin abrasions in that
area—including allowing trainers to stand on their rostrum while propelling them through and out of the water.
e dolphin’s lower jaw, or mandible, supports nearly the full force of the trainer’s bodyweight during tricks that involve
standing on the rostrum. e mandible is a sensitive structure that plays an important role in hearing. It is lled with
delicate fatty tissue that allows dolphins to receive underwater sound vibrations through the jaw bone. ese are then
transmitted directly to the inner ear, where they’re perceived as sound (Rommel, Costidis, & Lowenstine, 2018).
us, the bones and joints of and around the mandible are important to the animals’ acoustic health, and routine
exposure to excessive or abnormal force on these structures could not only be uncomfortable but even cause damage.
ARTIFICIAL BREEDING
Female dolphins at SeaWorld are routinely impregnated either when they’re conned with sexually mature males or
through forcible articial insemination (AI), which often requires sedation with diazepam so that semen can be manually
deposited into the reproductive tract using a catheter (Robeck et al., 2005). SeaWorld even employs articial reproductive
techniques to manipulate the sex ratio of its captive dolphin population and manually select for female calves in the hope
that they will grow into successful breeders. Indeed, out of 30 sex-selected inseminations, 28 have resulted in the births of
females (Robeck, O'Brian, & Atkinson, 2018).
Despite frequent claims by SeaWorld that its AI techniques may one day be used to assist conservation eorts (Robeck
et al., 2004), it’s unlikely that such invasive techniques would ever be attempted or successful with an endangered animal
in the wild. e reasons for this are multifaceted and include behavioral, physiological, and logistical constraints (Rose
& Parsons, 2019). For one thing, successful AI procedures require precise knowledge of the reproductive physiology and
endocrine function of the species. Dierent species of cetaceans have dramatically dierent reproductive physiologies,
making AI techniques that were successfully applied in one species unlikely to succeed in another (Robeck et al., 2018).
PEOPLE FOR THE ETHICAL TREATMENT OF ANIMALS | 5
© dreamstime.com/Izanbar
Furthermore, such AI procedures are invasive and uncomfortable, if not painful, to animals, who often require sedation
even when fully habituated to human handling. Endangered species of cetaceans are often uniquely, and sometimes fatally,
vulnerable to the stress of handling, making it unsafe to perform AI procedures that require capture, restraint,
and prodding of the reproductive tract (Rojas-Bracho et al., 2019).
us, it is exceedingly clear that SeaWorld’s dolphin-breeding program will never directly support conservation eorts
and does not exist for that purpose. On the contrary, AI is conducted at the park for the sole and obvious purpose of
producing more dolphins to ll the company’s tanks for prot, all while condemning animals to a miserable existence
devoid of all the things that are meaningful to them and necessary for their well-being.
CONCLUSION
Dolphins at SeaWorld are conned to articial, highly unnatural environments that prevent them from performing
even the most basic, biologically driven behavior and routinely expose them to damaging psychological trauma, social
stress, and physical injury. eir well-being is compromised when they are exposed to excessive anthropogenic noise
and harassment from crowds of park visitors and conned to severely crowded, barren enclosures that oer them no
means of physical or visual escape and thwart their natural use of sonar. Housing them in such conditions not only
is detrimental to their health and well-being but also sends the harmful message to the public that conning them,
repeatedly harassing them, and depriving them of everything natural and important to them is acceptable—a message
that can stie compassion in park visitors and confound good conservation eorts.
ese highly intelligent, socially and emotionally complex, far-ranging carnivores are among the most exploited of all
the captive wild animals in the United States. In 2014, after public sentiment shifted overwhelmingly away from
keeping dolphins in captivity and advancements were made in scientic knowledge regarding their welfare in captivity,
the National Aquarium in Baltimore announced plans to retire its remaining dolphins to a seaside sanctuary, noting,
“Times have changed, and our understanding of the needs of the animals in our care has changed.” SeaWorld should follow
suit, but it must immediately stop abusing dolphins by allowing trainers to ride on their backs and stand on their beaks.
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