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Do you want killer whales moved to “sea sanctuaries”?
(aka. sea pens or sea cages)

Keiko pen 3.jpg

The most common call to action about zoological whales, other than releasing them outright, is what’s called “sea pens”, “ocean pens”, the romantic flowery term “sea sanctuaries”, or, by some, “sea cages”.


They are either floating net cages, or a fenced-off piece of coast. I am going to talk about killer whales specifically, as they are what the biggest campaigns are about, and because they are a trickier animal to house than species that are more commonly kept in sea pens, like bottlenose dolphins. But I may bring up other species for reference and comparisons.


I can find about nine instances of killer whales being kept in sea pens, excluding early capture locations in Washington and British Columbia between 1967-1976 (in Iceland, new whales went to a pool, not a pen), but I’m also including TINRO Center in Okhotsk, because it’s the only recent location on Earth where killer whales lived in pens.

The argument is that sea pens are more “natural” to the whales (resort to nature-fallacy - no argument, just emotion), that they have “real sea water”, with “real ocean currents”, and it’s “almost like being in the wild”. Pure emotional propaganda, with no substance, logic, facts or actual meat on how it’s going to positively affect the animals at all.

There are those with a little more meat on their bones, who would say that sea pens are larger than pools (and the argument can easily be made that larger areas are beneficial for the animal’s mental and physical well-being - see my article on pool sizes for that), and are more enriching than a simple “concrete pool”.


So (almost) all sea pens keeping killer whales - here they are!

Below are all known sea pens killer whales have resided in, from the 1960s to the 2010s.

Sea pens.png

Keiko’s bay pen

In 1998, Keiko was moved from Oregon Coast Aquarium after 2½ years of rehabilitation, to Iceland. He was placed in a floating net cage, in a secluded bay of Heimaey, a small island just south of Iceland.

Note that the pen was nowhere near as large and fantastic as activists perhaps dream a sea pen would be. It was 250 feet across (split into two large and one small area), 100 feet wide, and 30 feet deep. Or in metric, 76 meters by 30, and 9 meters deep. It contained almost 5.5 million gallons.

Keiko pen.png

For comparison, we have Shamu Stadium at SeaWorld San Diego, shown below. The D-shaped main pool is 165 (one source says 170) by 80 feet (50 by 24 meters), and 35 feet/10.5 meters deep (note that the depth always appears much reduced from photos like these due to water distorting our view). It contains almost 3 million gallons.

The two large side pools are 120 x 75 feet, and 15 feet deep, or 36.5 x 23 x 4.5 meters, and contain just under one million gallons each. The fourth pool, to the right, is 125 x 75 feet and 30 feet deep, containing 1.7 million gallons.

Note then that this pool complex is over 30 years old, and we could easily build bigger and better pools today. But even at its dated age, the main pool is not terribly smaller than Keiko’s pen, which was not a single pen anyway, but split into two areas (so really, the two areas were about 115 x 100 feet each, and 2.75 million gallons, thus smaller in both length, depth and volume than Shamu Stadium’s main pool).

San Diego.jpg

Marineland Antibes pool complex is a little over twenty years old, and is the largest killer whale facility in the world, before Chimelong Ocean Kingdom unveils its pool complex.

It is 210 feet by 100 feet, and 40 feet deep (64 x 30 x 12 meters), with a total (entire complex) volume of 11 million gallons.

There is no real reason we couldn’t build something even larger than this, but as long as the pods stay around the size of 3-12 animals, the facilities don’t need to get bigger. In the early days, the pools were so small they could negatively affect the mental and physical health of the animals, but that is not the case in these modern facilities.

Information in the cost of Keiko’s pen, both the construction and maintenance, will be added. This was done entirely by donations (more on that below).


Springer’s rescue pen

Springer’s pen was a very temporary enclosure (it only took 30 days between rescue and release), and only contained a single juvenile whale, but I am bringing it up for the sake of completeness.

It was a floating net cage, 40 x 40 feet, and 12 feet deep. (12 x 12 x 3.6 meters.) [Link]

Sealand Haida.jpg

Sealand of the Pacific


According to a video produced by SeaWorld around New Years 1992 (in applying for their importation of the killer whales), Sealand’s killer whale pen was 100 by 70 feet (30 x 21 meters), and 35 feet deep (10 meters), so slightly smaller than SeaWorld San Diego’s back pools, with the depth of a show pool.

The medical pool or module, a closed in space with roof and solid walls, was 31 feet by 23 feet, and only 12 feet deep. A grown male killer whale is easily over 20 feet, and a female 18, if we’re talking Icelandic whales.

One whale, Miracle, died in this pen because activists tried to cut the net to free the whales, leading her to getting entangled and drowned.


Moby Doll’s pen


Moby Doll was the second killer whale ever caught for display. He was held for three months in a small harbour pen in Vancouver, in 1964.


Suffering from harpoon and gunshot wounds, and poor appetite from the stress of capture, he never had a good chance, but the poor quality of the harbour water has also been blamed in his demise. The dimensions of the pen are unknown.

It is obviously very outdated, I’m only including it for completness’ sake.

Seattle Namu pen_edited.jpg

Namu’s pen at Seattle Marine Aquarium


Namu was the first whale displayed after Moby Doll, in 1965. He lived for eleven months in a small harbour pen in Seattle.

Two causes of death have been given; infection from poor water quality, or becoming entangled and drowning in the pen’s netting.

Nami m-louis.jpg


Taiji Whale Museum


It is hard to say much about Taiji Whale Museum, except that they kept a number of killer whales there temporarily, either before they were sold or they died within months, and had only two long-term residents. Ku, for six years before being sold, and Nami, who lived there for a whopping 25 years before being moved to Port of Nagoya Public Aquarium. (I wrote more about the timeline of TWM’s killer whales here.)

What should be said about Nami is that after all those years, being captured in Taiji and put in that beach pen in 1985 (most of that time spent alone as she was aggressive with both humans and other animals), then being moved to an aquarium in 2010, she died after only seven months, at the age of 29 or 30.

Perhaps it simply was the stress of the move and the move to another sea pen would have killed her as well, perhaps she died because of the huge transition of going from a long life in a pen to being placed in a pool, or perhaps it was all a coincidence and she would have died soon at Taiji Whale Museum anyway. Some say she died because of her years in the sea pen, but that is ludicrous, as she did fine in it for 25 years, longer than almost any other killer whale in Japan. If the pen would have killed her, she would have died within a couple of years, back in the mid-80s.

What we do know however, is that her necropsy found she had 180 lbs (81 kg) of stones in her stomach, from swallowing them during all those years in Taiji. They still to this day have pilot whales, false killer whales, Risso’s dolphins and smaller dolphins in the same bay. It is unknown how deep or large it is, but it looks spacious compared to many other pens. Still, being by a beach, there is the problem of shallow water and ingestion of stones, and there is really no improvement over the highest standard of pools.


Izu-Mito Seaparadise


Izu-Mito Seaparadise is a Japanese facility that kept its killer whales in a small pen, in the middle of a well-populated coastal town of almost 200 000 residents. First Shachi, who died after two years, then Tanouk/Yamato for five years overlapping with Asuka, who lived there for ten years.

Obviously the place didn’t cause its animals instant death despite the close (immediate, I should say) proximity to human civilization, but one can wonder how ethical and healthy this was. Being so near boats going around, it would mean constant exposure to noise and pollution that simply don’t exist in a pool, and it is no larger than a modern whale pool anyhow, but the exact measurements are unknown.


Harry Rabin

Russian whales acclimitization pen/TINRO


I did say that I was not going to include any pens whales were kept in temporarily just after capture, mostly because there is practically no information on those in Washington and British Columbia. But I am including this because it is the only place recently, and after the 2000s at all, where killer whales have been kept in sea pens.

TINRO-Centre is located in Vladivostok in eastern Russia, and is a location for many recently caught belugas and killer whales from the Sea of Okhotsk.

Currently there are no whales there, but further permits have been applied for. A video, below, shows how the belugas live/d in the pens.

These are of course not the best we can build, just like a tiny pool in some substandard aquarium is not the best we can build, but I am showing them because they are sea pens (floating net cages) in use in the modern day, at least one with killer whales in it, but it goes to show sea pen, does not equal = good for the animals, or even large and “natural”.

The following is quoted from a document about the care and acclimitization of whales captured in 2012 and 2013, living at TINRO.

Placement and early adaptation of the new captured killer whales in sea cages filled with clean sea, located far from populated places, has significant advantage comparing to other possible variants (temporary or stationery pools, dolphinariums).

Animals stay in habitat with maximum similar to natural parameters of light, temperature mode, water composition and quality, noise and acoustic characteristics and, also, in similar environment: live fish moves free in the cage, another known marine dwellers are met, air is clean and free of chlorine evaporation, etc.


Whale microflora retains at the level close to natural (occurring in chlorinated sea water and its simulants oxidants do not destroy microflora), no excessive anthropogenic microbial burden. As a result, animal adaptation to new conditions and microflora re-arrangement develop much more smoothly, with less burden to immune system and decreased risk of infectious complication development.

Not denying anything that they are saying, they are dealing with the capture, acclimitization and “adaptation” of whales that until recently, had spent all their lives in the sea. The complete opposite of animals that were born or lived most of their lives in pools. So while this makes for an easier transition for wild animals just caught, some of the same things may mean more stress for animals used to living in pools, and completely unnecessarily. This does not at all mean however, that their positive experiences keeping whales in pens should be dismissed.

Vladivostok is very remote and far closer to pristine nature than anything on the American coasts, like California or Washington. The Atlantic coast in the east must surely, with its higher population density, be even worse, and Alaska is too cold, going down to only 26 degrees fahrenheit, SeaWorld’s whales being used to a constant 52.

They speak of “chlorine evaporation in the air”, but that is not a given. SeaWorld’s pools have less chlorine in them than American tap water, and I have myself visited two dolphinariums that were very different. Kolmården Dolphinarium, in Sweden, smelled clearly of chlorine. Batumi Dolphinarium in Georgia was outdoors, but even during and after swimming with the dolphins, I smelled only saltwater on myself, exactly like in the sea, while the hotel tap water smelled strongly of chlorine. Not all dolphinariums use chlorine to keep their water clean, and those that do, typically use small amounts.

The measurements of the pens are unknown, but they are obviously small, so any positive sides of keeping whales in them should come from, as they say, the ideal light, temperature, water composition that the whales already come from (again, being caught there), and not from vast spaces to roam, because there are none.


It is also extremely difficult to get ideal water quality and lack of noise, as described, as most places today are crowded with people, their pollution and noise from ships.

In 2020, the whale pens in Russia became a scandal, since more whales had been caught than was permitted, and their health was being threatened due to extremely cold weather and encroaching ice around the pens. This became viral online as "WHALE JAIL" and "orcas detained in prison!", and similarly emotionally charged, anthropomorphic language.

Yet wasn't this pretty much what the same anti-aquarium activists wanted? The whales are in the sea, they "feel the natural rhythm of the ocean", and all that. Isn't this pretty much the same basic scenario as "the whale sanctuary"?

But no, only when they do it.

And of course, TINRO showed why sea pens are so difficult to manage and why they make such a poor fit, especially for large animals like killer whales, particularly in cold waters (where Icelandic and Canadian whales also belong). They did share some of their difficulties with the Keiko project, more below.


Had they been in properly managed pools, they would not have suffered and their health would not have been endangered.

US navy pen

Ahab and Ishmael were two Southern resident killer whales who lived for a time at two different US Navy locations (California 1968-69, after that, Hawaii). Ishmael disappeared during an open ocean training exercise in 1971, while Ahab remained until his death in 1974, being trained and worked alongside a pilot whale named Morgan.

Each whale pen was 100 by 100 feet and 20 feet deep (30 x 30 x 6 meters, they look large in the image but they were smaller than Sealand, and only slightly larger than San Diego’s two shallow back pools), with a coral silt bottom. The outside training pen (seen in diagram below) was 540 x 600 feet (164 x 182 meters), and was only used to train the whales to follow directions in the open ocean, not for permanent living.

The text below was written at the time of use, in the early 1970s.

The majority of all captive marine mammals have been housed and trained in concrete tanks. Because of the extreme cost of constructing and maintaining such enclosures, they are usually built to minimum size and depth. The size of available work space greatly influences the kinds of behavior that the animal can be conditioned to perform.

The housing of marine mammals in fenced ocean pens, as employed at NUC, Hawaii, is a concept common to few biological facilities. Ocean enclosures have been used at NUC, Hawaii, for nearly 4 years with low maintenance costs and excellent animal health. Simplicity and low cost have allowed the construction of very large enclosures. These enclosures, in turn, have allowed the maintenance of pilot whales and killer whales in large, open areas, where normal behaviors are more likely to be exhibited.

With this, bear in mind that it was written in the early 1970s, and this is what killer whale pools looked like at the time:

60s pools.png

The 100 by 100 foot pens look huge, and are one of the best attempts at sea pens for whales, but they only amount to 900 square meters, compared to the SeaWorld show pool above which is over 1000 square meters (would be 1200 if it were a perfect rectangle).


They were also only 20 feet, or six meters deep, which is less than the body length of a grown male killer whale. The males and large females would thus have to live something like this:

Skana small pool.png

As seen in the above diagram, the larger pools at SeaWorld and Marineland Antibes are 35-40 feet deep, and we could easily build the Blue World Project today, at 50 feet deep. Keiko’s is the deepest known pen, at 30 feet.

Even as the biggest and most successful sea pens for killer whales, they do not match even outdated pools built in the 1980s and 90s.


Georgia Aquarium’s Ocean Voyager (where they keep, among others, their whale sharks) is 284 x 126 feet, or 86 x 38 meters, and 30 feet deep. That is a rectangular surface area of 3268 square meters, or 3.6 times bigger than the navy whale pens. Ocean Voyager compared to SeaWorld San Diego’s Shamu Stadium, below.

Shamu San Diego Ocean Voyager.png

This is not even the largest aquarium tank in the world, only the largest in the western hemisphere.

Worth adding is that Chimelong Ocean Kingdom in China, is just about to finish their killer whale pool which is reportedly 100 meters long and 30 meters wide. That is even longer than the Ocean Voyager tank, and the biggest single pool ever built for killer whales, by far.


Also we should take into account that this was over forty years ago, and the world population of humans has doubled since then. Finding an undisturbed piece of coastline with no pollution, radiation poisoning or noise pollution becomes harder and harder with every passing decade. Continuing, about the navy pens:

"To facilitate movement of the whales from enclosure to enclosure, 10x10-foot nylon net curtain gates were installed between pens and between the pens and the lagoon area. These net gates opened and closed by sliding up or down on vertical pipes. This style of gate was used for about 1 year until most of them were damaged by the whales “nosing” or chewing on them.


After being in place for 18 months, most of the pen mesh was heavily overgrown and corroded, and was replaced. At this time the net curtain gates were replaced with vertically sliding “guillotine” gates. On the new gates a 10x10-foot-square piece of 6-inch mesh wire mounted on a pipe frame replaced the nylon netting. These gates were heavier and required a pulley and hand winch for closure, but were sturdier and less susceptible to biological and mechanical fouling."

US Navy pen.png

"In February and March 1970 a large enclosure measuring 540x600 feet was built by enclosing the lagoon area adjacent to the whale holding pens. Fence posts were spaced at 30-foot intervals and 6-inch mesh galvanized wire was used. A large nylon net curtain gate put into the bay side of the enclosure, was large enough to allow the passage of work boats. All four holding pens opened into the enclosure, and the area was used extensively for intermediate and advanced training preceding the open-bay release of the whales."

Naomi Rose

Dr. Naomi Rose is a well-known “rock star” of the animal rights movement specifically when it comes to cetaceans (despite having only five minutes hands-on experience with cetaceans), and has long campaigned for SeaWorld and other parks to give their animals up and put them in sea pens.

But at the same time, she speaks of how sea pens are detrimental to the animals in many ways, essentially “death traps”!

So which one is it? Is she campaigning for something she admits is bad for the animals?

This is the same woman who says she is an activist first, a scientist second, and that activism and science can coexist. She was one of the people responsible for Keiko in his final days, and made sure he was kept out of public view in a second small beach pen, made sure he was starved of food as well as human companionship, and when he died months later, buried him without a necropsy.

Keiko Taknes Bay.JPG

Visser’s "SeapenWorld"

In 2015, Ingrid Visser, an activist-researcher from New Zealand, revealed her true purpose for wanting to close down SeaWorld and other marine parks with cetaceans. To open her own! (SeapenWorld is not a real name, I put it there for comedic effect, if you will.)

She intends to put 300 cetaceans (funnily enough, pretty much the exact number of whales and dolphins kept in North America) in a single location i Washington state, the exact place where the Southern resident killer whales are going extinct due to pollution and radiation poisoning, as well as overfishing. So let’s put 300 animals in a confined area with nothing but the ocean waves to filter out their waste, what a great idea!

The idea is to have…

  • Ticket booths and guest facilities

  • Room to house more than 300 whales and dolphins

  • Underwater viewing tunnel for guests

  • Research facility


Essentially, her own SeaWorld park!


The only real difference being no advanced filtering system, and no real way of caring for the animals. As these anti-zoo activists show a constant disdain for the human-animal relationship in favor of a “hands-off” approach, one can only imagine the animals being simply left to “fend for themselves”, and as in elephant sanctuaries, if an animal doesn’t want to cooperate in its own healthcare, it’s simply allowed to be sick or injured (since they don’t believe in animal training, and have no understanding of it).

The very practices and facilities that make the modern zoo such a great place for animals, would be missing. Left would be animals swimming in polluted water in a foreign environment, deprived of the human attention and love they’ve grown up with, and deprived of even basic husbandry training to ensure their own health.

"In positioning themselves as the only advocates on behalf of these animals, the organizers behind this plan seem to be suggesting that it’s OK for them to operate a marine park which welcomes guests to educate the public about these animals, but it’s not OK for accredited, science-focused zoological facilities to do the exact same thing – facilities which comply with the law, are held to rigorous animal care standards, provide exceptional veterinary care, and give love and dedication to all animals, including rescues."


- Scott Higley, Vice President for External Affairs & Government Relations, Georgia Aquarium

When they do it, it's "prison"
But when we do it, it's "sanctuary!"

The Beluga Whale "Sanctuary"

In 2020, what was called "the world's first whale sanctuary" was unveiled, in none other than the exact same bay where Keiko's pen had once been, 18 years prior. The idea behind this is something of a mystery, since beluga whales are not native to waters anywhere near Iceland. They are an exotic species there. The location had already seen great challenges with the four years Keiko lived there, as was documented at length, so the location was likely chosen due to its "celebrity" status.

As of writing this, in late 2022, the two female beluga whales live in a pool, on dry land. Oh, some PR shots of the whales swimming around the bay were taken, but as you can see above (right), the actual "sanctuary" consists of three small pens, no bigger than those of the "whale jail" in Russia. And as it is, they live in a pool, not in the sea in any way.

How is it a "sanctuary"? How is it a "world's first", in any way?

They are not the first keeping cetaceans, or belugas specifically, in sea pens.

They are not the first not having a breeding program.

They are not the first not having shows.

They are not even the first being run by an animal liberation ideology, as we had Keiko.

What are they unique at, exactly?

As it is, this is a scamtuary in the same vein as many exotic wildlife "sanctuaries", and they even have their whales on public display for profit, $20 a head. The project even confirms what has been said elsewhere, that sea pens like this, especially in cold, harsh climates, are a very poor fit for animal welfare and safety.

Keiko Klettsvik belly.jpg

"It is disingenuous to suggest that a non-profit organization is by default also a righteous one. It was a non-profit that subjected Keiko to a drawn-out, suffering and unnecessary death. It is the same organizations that continue to defraud the public on the subject of Keiko to this day.

There is one remarkable difference in Dr. Visser’s vision; her concept facility is a proposed halfway house for release to the wild. There is not one indisputable case of a whale or dolphin from long-term zoological care ever being successfully released to the wild. In fact, most attempts have ended in tragedy. The idea that whales long in the care of humans can survive an unforgiving wild is nothing short of premeditated animal abuse. Life is not so simple as Hollywood or Dr. Visser would have us believe.

The proper care of marine mammals like whales or dolphins is an immensely expensive undertaking, one killer whale costs nearly US $100,000 a year just to feed. This figure does not consider the cost of facility construction, preventative health care, labor, food storage or ongoing facility maintenance (extreme in an open-ocean environment). The tax status of the organization won’t change this fact.

Keiko pen 1.jpg

To understand why these kinds of sea pens are a poor option for these killer whales, it helps to understand the life they lead at SeaWorld. In the activists’ opposition to zoos and aquariums, they routinely misrepresent the facts about SeaWorld’s killer whale habitats, veterinary care, enrichment, social interaction and training.

On SeaWorld’s commitment to these animals, I agree completely with the Association of Zoos and Aquariums. They are “meeting or exceeding the highest standard of animal care and welfare of any zoological organization in the world.”

Recent peer-reviewed research shows that SeaWorld’s family of killer whales is living as long as some of the most studied wild populations. But what’s more interesting is the trend reflected in life span, longevity and infant survivability of SeaWorld’s population.

If the next decade is anything like the last, SeaWorld killer whales will outlive their wild counterparts by no small margin. This could never happen with distressed and suffering animals.

Animal rights groups also misrepresent what life is like for a killer whale living in one of these ocean enclosures.

I was a member of the team that cared for Keiko, the whale made famous in “Free Willy,” before his tragic, unnecessary and premature death in 2003. Keiko spent most of his life in the “wild” living in one of these enclosures in Iceland.

I was present (more than once) when the pen was effectively destroyed by a storm. I was present when Keiko would play with (and likely swallow) foreign objects he retrieved from the seafloor. I was present, on more than one occasion, when Keiko fell ill from exposure to pathogens he would never encounter in a zoological setting.

Regrettably, I was not present – sometimes for days at a stretch – when severe weather kept us from tending to him at all.

Killer whales cannot be compared to other species sometimes moved to “sanctuaries” such as elephants and chimpanzees.

The marine environment is an unforgiving and treacherous place to be sure, but beyond the obvious physical challenges, there are arguably more dangerous aspects invisible to the inexperienced eye.

Retirement is a human concept that doesn’t exist in nature. “Sanctuary” is a counterfeit term often used as an alternative to “captivity.” The contrast is intended to play on emotion.

No animal is well served by this. It is precisely this same mentality – oversimplified and emotional – that lead to Keiko’s death.

Imagine your family dog placed in a large fenced area in a field. They receive food, but little to no human contact defines their life. This is what the activist community wants for SeaWorld’s family of killer whales.

Some of those who advocate loudest for sea pens have only one example on their resume: Keiko. The title of my book on this subject, “Killing Keiko,” is blunt and it is true. Animal rights activists killed that animal. Had the Keiko Release Project taken place in U.S. jurisdiction, those same individuals would be faced with prosecution under the Marine Mammal Protection Act, and for good reason.

There is no question that marine animals, including cetaceans, can be safely cared for in netted ocean enclosures. There are accredited organizations whose commitment to animal welfare should never be questioned that have cared for their animals in these types of enclosures for many years; among them the United States Navy. But for SeaWorld’s killer whales – the vast majority of which were born in human care – these ocean enclosures are a poor choice."


- Mark Simmons

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