Pacific White-Sided Dolphins - Wild, Rescued and Captive
Pacific white-sided dolphins are intelligent, playful and very social animals. They live in large groups and often approach boats. They are attractive dolphins that are fascinating to observe in the wild. Unfortunately, they are also kept in captivity in aquariums and marine parks. Sometimes this is necessary because an animal has been injured. The rescued animal may no longer be able to survive in the wild, even after it has been treated. In my opinion, this is the only justification for keeping a dolphin in captivity.
This article tells the story of both the wild dolphins and the two rescued Pacific white-sided dolphins at the Vancouver Aquarium in British Columbia. Helen and Hanna were deemed unreleasable and lived together at the aquarium for ten years. Recently, a sudden and tragic illness claimed the life of Hanna, despite some very impressive attempts to keep her alive. Helen currently swims in her tank alone, but she may soon have company. Chester is a rescued false killer whale calf who has also been deemed unreleasable. He and Helen will soon be introduced.
The scientific name of the Pacific white-sided dolphin is Lagenorhynchus obliquidens. Like other dolphins, porpoises and whales, it belongs to the order Cetacea. The animals in this order are often referred to as cetaceans.
The Pacific White-Sided Dolphin - An Attractive Animal
Pacific white-sided dolphins live in the northern part of the Pacific Ocean. Although their exact colouration varies, in general the animals have a black back, grey sides with a white or light grey stripe, and a white throat and belly. The dolphin's lips are black.
The dorsal fin on the animal's back has a strong backwards curve and sometimes looks hooked. The fin is black on its upper portion and grey on the lower portion. The dolphin also has a pectoral fin on each side of its body. Some people prefer to call the pectoral fin a flipper, since unlike the fin of a fish it contains bones. The flipper bones resemble a short version of our upper arm, forearm and fingers. This reminds us that whales are mammals, like us, and that their distant ancestors were land animals. The dolphin's tail is made of two lobes called flukes.
Pacific White-Sided Dolphins Swimming Beside a Boat
Life in the Wild
Pacific white-sided dolphins live in large groups that generally contain from ten to a hundred animals. They have also been observed in "supergroups", which may contain thousands of animals. They are sometimes seen in the company of other dolphin species or of whales. The dolphins frequently approach boats and ride on the bow waves. They are acrobatic and playful animals that often leap out of the water and do somersaults.
Like other cetaceans, Pacific white-sided dolphins breathe through a blowhole on top of their head and need to come to the surface periodically to obtain oxygen. They can stay submerged for up to six minutes. They communicate with each other by whistles as well as by touch. Evidence suggests that each dolphin has its own signature whistle.
The dolphins feed on small fish and squid, which they find by echolocation. During this process, a dolphin emits high pitched sounds. The sound waves bounce off objects and return to the dolphin, giving them an impressive amount of information about their environment. This information includes the location of an object, its shape, density and speed and its distance.
Pacific white-sided dolphins reach sexual maturity between the ages of seven and ten. The gestation period is twelve months. Females don't give birth every year. There seems to be a three or four year interval between births.
Pacific White-Sided Dolphins Swimming Underwater
The Vancouver Aquarium
The Vancouver Aquarium is located in Stanley Park, which is located near downtown Vancouver. The aquarium is a non-profit organization dedicated to education, research and conservation. It actively participates in all these areas. It's a popular institution for schools, tourists and local people.
Like other facilities that house marine mammals, the aquarium periodically faces criticism from animal rights activists for keeping intelligent and sentient beings like cetaceans in captivity. The aquarium has evolved over the years, however. Since 1996, it no longer captures wild cetaceans. Any cetaceans that it does accept are either rescued animals that lack the skills to survive in the wild or animals born in other facilities. Some of the rescued animals come from the aquarium's own Marine Mammal Rescue Centre, which helps local animals in distress and releases them back into the wild whenever possible.
Another factor that draws the ire of animal rights activists is the death of a cetacean from anything other than old age. There have been several of these deaths in recent years. The survival of whale and dolphin calves has been a particular problem.
I have no doubt that the aquarium staff care deeply for their charges, as I've often observed. It's unnaturał for a marine mammal to spend its life in a restricted area that gives them little to do, however. It's hard to imagine that this doesn't affect their health and resilience.
Spinnaker, Helen and Hanna at the Vancouver Aquarium
Spinnaker, Hanna and Helen lived together at the Vancouver Aquarium. According to the aquarium, all three dolphins were rescued after becoming entangled in Japanese fishing nets. They were declared unreleasable due to their injuries. The pectoral fins on the sides of Helen's body were partially amputated as a result of her entanglement in the net. Rumours persist that the dolphins were actually injured in the annual Taiji dolphin drive, a horrible event in which dolphins are caught for food and trapped for dolphinaria. The aquarium adamantly denies that this is true.
Spinnaker, the only male in the group, died in 2012 after a lengthy illness. He was about twenty-five when he died. Hanna lived to be twenty-one years old. Helen is currently twenty-seven. The maximum lifespan of Pacific white-sided dolphins is somewhere in the forties.
Helen and Hanna performed in shows, as shown in the video below. Like the aquarium's policy on obtaining animals, the cetacean shows have evolved over the years. The animals no longer perform showy and unnatural tricks. The behaviours that they do exhibit during a show are ones that they perform in the wild.
Dolphin Show - Helen and Hanna Perform
Hanna's Illness and Death
On Monday, May 18th, 2015, staff members noticed that Hanna was behaving abnormally. The aquarium's head veterinarian was contacted. With the assistance of "one of the world's top dolphin radiologists", the vet diagnosed gastrointestinal distention and inflammation. This is a condition that is known to progress rapidly and to be life threatening.
As Hanna's condition worsened, the vet gathered together dolphin medical experts from around North America. They decided that the only treatment that had any hope of saving Hanna's life was to perform the world's first intestinal surgery on a Pacific white-sided dolphin under general anesthesia.
Against all odds, Hanna survived the surgery, which was performed on Thursday evening. By Saturday morning she was showing some signs of improvement. Sadly, on Sunday morning her condition began to deteriorate. She died on Sunday evening.
The cause of Hanna's problem is believed to be a common, non-infectious bacterium. Test results may confirm this suspicion. I hope the aquarium is able to determine how Hanna's illness arose and that something can be learned from her death. Helen has shown no signs of the illness.
Helen's Life at the Aquarium
I recently visited the aquarium and observed Helen. Every time she was at the water's surface in the shallow pool, she repeatedly lifted her head out of the water with a jerk while opening and closing her mouth. Her behaviour suggested that she had just regurgitated food. Each time I returned to Helen's tank after looking at other animals she was still performing this odd behaviour. It looked very much like the repetitive actions that some captive animals perform under stress. Regurgitation and playing with the regurgitated food is a known indicator of boredom in captive cetaceans.
Interestingly, I found the YouTube video below showing this same behaviour taking place while Hanna was still alive and while the dolphins were performing shows. The video was posted a year ago. Both dolphins were in the small pool, even though the big tank was available to them. I find it so sad that even then - and probably long before - the dolphins were indicating that they were bored.
I think that the aquarium is a wonderful educational resource. There is far more to see there than just marine mammals. I also applaud the aquarium's rescue and research efforts. However, I think that much more needs to be done to support the cetaceans that live there. They need to have more space, more enrichment with respect to activities and a better life.
Stereotypical Behaviour in Pacific White-Sided Dolphins
How Could the Problem of Cetaceans in Captivity Be Solved?
The problem of eliminating the keeping of cetaceans in captivity or of improving their lives is not as easy as it sounds. The following methods have been suggested with respect to the Vancouver Aquarium's cetacean population.
Attrition: Some people have suggested that the aquarium's cetacean population should be removed by attrition. According to this plan, after each animal dies, no replacement would be brought into the aquarium. The problem with this idea is that the last animals would have a miserable existence, since they would have no company. Cetaceans are social animals.
Transfer: Another suggestion has been to transfer whales and dolphins to larger facilities which have more animals. This would solve the problem of the unhappy lives of the last Vancouver animals left by attrition. One possible problem is that in larger captive populations more breeding would occur, potentially increasing the size of the captive population. Still, the transfer could improve the lives of the Vancouver Aquarium cetaceans.
Enhanced Habitat: The aquarium's current cetacean habitats could be expanded and enhanced. Getting permission to expand further into Stanley Park - a major and much loved tourist attraction - is always difficult, however. In addition, some people worry that if the aquarium expands it will obtain more cetaceans. This is another controversial topic. From one perspective, obtaining more Pacific white-sided dolphins would be good, since it would create a more natural community for Helen. (Providing a suitable community for Chester could be an additional problem.) The dolphins would need much more space to enable them to live a reasonably happy life, however.
Rehabilitation: It's been proposed that the cetaceans presently at the aquarium be released into the wild. This is not really a viable option. It would be very difficult to teach a cetacean that has been raised in captivity how to survive in the wild, even if we knew all the things that the animal needed to learn. The Marine Mammal Rescue Centre does rehabilitate cetaceans and other marine mammals, but all of these animals were rescued as adults or are able to survive in the wild. While it's true that Helen was rescued as a adult, she was deemed unreleasable in Japan due to her damaged pectoral fins.
Other ideas are being investigated to help rescued cetaceans and the problem of keeping them in captivity. One is the use of birth control drugs for captive cetaceans. Another is the creation of large sea pens to protect rescued animals and let them live a somewhat normal life.
Chester the False Killer Whale Calf
In July 2014, the aquarium's Marine Mammal Rescue Centre rescued a young false killer whale. He was stranded in shallow water on Chesterman Beach in Tofino, Vancouver Island, and has since been named Chester. Chester was only four to six weeks old when he was found. He was injured, in distress and abandoned. After receiving intensive care, he has recovered well. However, he lacks important survival skills that he would normally have learned from his mother and other members of his species.
The scientific name of the false killer whale is Pseudorca crassidens. The animal has a wide distribution in both temperate and tropical regions. Despite this fact, little is known about its life in the wild.
Chester and Helen's Future
Fisheries and Oceans Canada (a government organization) investigated Chester's situation. They declared that he was unreleasable due to his lack of skills. The aquarium says that false killer whales and Pacific white-sided dolphins have lived together successfully in other facilities. They plan to place Chester in Helen's habitat. Each animal would then have company. In addition, Chester would have a bigger swimming area than he currently has in the aquarium's research facility.
The plan to house Chester and Helen together sounds good in theory. There are a number of questions to be answered, though. First, we need to know if the two animals will accept each other's presence in the same habitat. Secondly, we need to discover whether they have enough in common to become good companions instead of remaining simply two animals that tolerate each other. They are after all different species with different behaviours.
There are other problems that concern me. False killer whales are not as bulky as killer whales, or Orcas, but they are considerably larger than Pacific white-sided dolphins. I wonder whether the tank will be big enough for the two animals, especially as Chester grows in size. There will be enough physical space for them, but whether there will be enough space for the animals to have a good life and enough things for them to do is another question. In addition, Helen will still have only one companion. Two animals is nowhere near a big enough community for a Pacific white-sided dolphin.
The habitat is currently being modified for Chester's arrival. The aquarium says that Chester is now a "rambunctious young male learning his boundaries". In order to keep him safe, aquarium staff are adding mesh and padding to the habitat. I'll visit the aquarium again when Chester arrives at the habitat to see how things are going.
A Better Life for Helen
It's sad to see Helen on her own. Aquarium staff members did come to talk to Helen on my last visit to the aquarium, which she seemed to appreciate, but they didn't stay with her. Helen isn't being ignored, but she needs a full-time cetacean companion instead of part-time human ones.
Pacific-white sided dolphins form close knit groups in the wild. Helen lived with Hanna for a long time. She is almost certainly missing her companion. The fact that her habitat is being altered to accommodate Chester is probably adding to her stress.
As some people have said, it's impossible for even the best aquarium or marine park to give animals like the Pacific white-sided dolphin a truly natural life. In the wild, the dolphins travel unimpeded for long distances and in large groups in their search for food. They frequently vocalize or interact with each other in some way, creating a rich social life. This situation can't be replicated in captivity. For rescued animals, though, we need to do the best that we can.
The sooner the habitat alterations are finished the better. I hope very much that Chester and Helen accept each other's presence. I also hope that I will soon be able to update this article with the news that both Helen and Chester seem to like their new companion. This may not be the end of the story, though. The problem of providing Helen with a more interesting life will probably still exist, as will the need for enough space for a growing false killer whale and a Pacific white-sided dolphin.
Update - Chester in his New Home
Update July 2015
The changes to the habitat have now been finished. Chester was recently placed in the habitat and introduced to Helen. Based on my observations made during an afternoon visit to the aquarium, the two animals seem to be accepting each other's presence with no problem. They came very close together when being fed but not when they were left on their own. They are still getting to know each other, though. One of the aquarium staff said that the relationship between the two cetaceans is changing daily. It's an exciting time.
I was very happy to see that even when Helen voluntarily stayed in the smaller tank, she seemed much happier than on my last visit. She didn't exhibit any stereotypical behaviour and even seemed to be looking at visitors with interest.
Chester is being treated with care. The area right next to the windows of the underground viewing area was roped off and monitored by a staff member during my visit. This prevented Chester from being upset by actions such as people tapping on the glass. Far from being upset, he seemed to be curious about all the people watching him and posed very nicely for photographs.
Helen gave a short and simplified performance during my July visit. The performance was based on her natural behaviours, as mentioned above. Her enthusiastic jumps into the air were especially popular. Chester already follows some instructions. When asked to do so, he opened his mouth to get his tongue patted and teeth rubbed, turned upside down to show his undersurface and swam to a different trainer łocated nearby.
I'll be watching the progress of Chester and Helen with great interest. Hopefully they will eventually become good companions, even though they belong to different species. The early signs are good. Time will tell whether a friendship is possible between the two animals.
© 2015 Linda Crampton