The Vancouver Aquarium is a public aquarium located in Stanley Park in Vancouver, British Columbia, Canada. In addition to being a major tourist attraction for Vancouver, the aquarium is a centre for marine research, ocean literacy education, conservation and marine animal rehabilitation.The Vancouver Aquarium was one of the first facilities to incorporate professional naturalists into the galleries to interpret animal behaviours.Prior to this, at the London Zoo Fish House, naturalists James S. Bowerbank, Ray Lankester, David W. Mitchell and Philip H. Gosse (the creator of the word aquarium) had regularly held "open house" events, but the Vancouver Aquarium was the first to employ educational naturalists on a full-time basis. Aquarium research projects extend worldwide, and include marine mammal rescue and rehabilitation.On August 9, 2010 Prime Minister Stephen Harper and B.C. Premier Gordon Campbell announced capital funding of up to $15 million. The province would donate $10 million in funding over the next three years to help pay for a planned expansion of the 54-year-old facility, Premier Gordon Campbell said. Harper added that Ottawa would hand over up to $5 million to the aquarium for infrastructure upgrades. The aquarium, however, remained nonprofit organization. The property is owned by the City of Vancouver and rented to the aquarium for $40,000 a year since 1991 (prior to which it was $1 per year).In October 2009 the Vancouver Aquarium was designated as a Coastal America Learning Center by the US Environmental Protection Agency. As the first Learning Center in Canada, this designation is intended to strengthen the Canadian/U.S. partnership for protecting and restoring shared ocean resources.On August 31, 2020, the non-profit announced on Facebook that due to the financial stresses caused by the ongoing COVID-19 pandemic, it was pausing its public programming for the time being while it engages in strategic planning for the financial sustainability of its future operations. On April 15, 2021, the Aquarium announced that an agreement had been signed to transfer ownership from the Ocean Wise Conservation Association to Herschend Family Entertainment.C.C.C.
Lowering heart rate while diving helps marine mammals regulate blood pressure while redistributing blood flow and conserving oxygen during extended dives. However, the classic characterization of this dive response—as a pronounced and abrupt reduction in heart rate observed during forced dives in laboratory settings—contrasts with the higher minimum heart rates and oscillatory patterns observed in freely diving marine mammals in the wild. To assess this apparent discrepancy in cardiovascular control, we measured the heart rates of three Steller sea lions (Eumetopias jubatus) using subcutaneous cardiac monitors during trained stationary dives (3–4 m) in an aquarium pool. During 12 of the longest dives (76–161 s), heart rates decreased from an average of 95 to 34 bpm within the first 26 s of submergence. However, while mean HR at depth eventually averaged around 31 bpm, it also oscillated between 27 and 39 bpm every 5–6 s (0.2 Hz) for much of the dive, before rising prior to surfacing. The observed relatively slow drops in heart rates were similar to those seen in other marine mammals, suggesting an optimal rate of decline that reflects the anticipated conditions of voluntary dives. We further hypothesize that the oscillating minimum heart rates of freely diving marine mammals reflect time delays in the baroreceptor reflex due to the prolongation of circulation time. Our findings suggest these delays shape the rate and pattern of heart rate decline, ultimately influencing cardiovascular control, gas management, and breath-hold duration in diving mammals.
Sea otters (Enhydra lutris) exhibit morphological and physiological adaptations supporting a mass-specific resting metabolic rate (RMR) 2.9-fold higher than predicted for terrestrial mammals of similar size. Their elevated metabolism results primarily from thermogenic mitochondrial proton leak to compensate for heat loss in the marine environment because of their high surface-area-to-volume ratio, combined with their reliance on fur insulation rather than blubber. Key respiratory adaptations include an enlarged lung volume, 3.5-fold greater than predicted allometrically, and a proportionately elevated tidal volume, enabling efficient oxygen uptake and carbon dioxide elimination. Complementary cardiovascular adaptations include a heart mass 1.3-fold greater than the allometric prediction, a correspondingly elevated stroke volume, normal heart rate, increased hemoglobin concentration, and enhanced arterial oxygen content. Together, these adaptations result in an elevated cardiac output and enhanced convective oxygen transport to support the elevated RMR. These multi-level adaptations, present even in young animals, likely evolved under selective pressures favoring thermogenesis over increased insulation by blubber, representing a convergent evolutionary strategy consistent with the principle of symmorphosis, similar to terrestrial athletic mammals adapted for sustained aerobic performance rather than energy conservation. Additional benefits of enlarged lungs, such as enhanced buoyancy and pulmonary oxygen stores, may also have contributed to their evolution.
The increased size and enhanced compliance of the aortic bulb-the enlargement of the ascending aorta-are believed to maintain blood flow in pinnipeds during extended periods of diastole induced by diving bradycardia. The aortic bulb has been described ex vivo in several species of pinnipeds, but in vivo measurements are needed to investigate the relationship between structure and function. We obtained ultrasound images using electrocardiogram-gated transesophageal echocardiography during anesthesia and after atropine administration to assess the relationship between aortic bulb anatomy and cardiac function (heart rate, stroke volume, cardiac output) in northern fur seals (Callorhinus ursinus) and Steller sea lions (Eumetopias jubatus). We observed that the aortic bulb in northern fur seals and Steller sea lions expands during systole and recoils over the entire diastolic period indicating that blood flow is maintained throughout the entire cardiac cycle as expected. The stroke volumes we measured in the fur seals and sea lions fit the values predicted based on body size in mammals and did not change with increased heart rates, suggesting that greater stroke volumes are not needed for aortic bulb function. Overall, our results suggest that peripheral vasoconstriction during diving is sufficient to modulate the volume of blood in the aortic bulb to ensure that flow lasts over the entire diastolic period. These results indicate that the shift of blood into the aortic bulb of pinnipeds is a fundamental mechanism caused by vasoconstriction while diving, highlighting the importance of this unique anatomical adaptation.
Marine mammals may develop kidney stones, which can be challenging to treat. We describe burst wave lithotripsy (BWL) and ultrasonic propulsion to treat ureteral calculi in a 48-year-old female bottlenose dolphin (Tursiops truncatus) and to reduce renal stone burden in a 23-year-old male harbor seal (Phoca vitulina). BWL and ultrasonic propulsion were delivered transcutaneously in sinusoidal ultrasound bursts to fragment and reposition stones. Targeting and monitoring were performed with real-time imaging integrated within the BWL system. Four dolphin stones were obtained and fragmented ex vivo. The dolphin case received a 10-min and a 20-min BWL treatment conducted approximately 24 h apart to treat two 8–10 mm partially obstructing right mid-ureteral stones, using oral sedation alone. For the harbor seal, while under general anesthesia, retrograde ureteroscopy attempts were unsuccessful because of ureteral tortuosity, and a 30-min BWL treatment was targeted on one 10-mm right kidney stone cluster. All 4 stones fragmented completely to < 2-mm fragments in < 20 min ex vivo. In the dolphin case, the ureteral stones appeared to fragment, spread apart, and move with ultrasonic propulsion. On post-treatment day 1, the ureteral calculi fragments shifted caudally reaching the ureteral orifice on day 9. On day 10, the calculi fragments passed, and the hydroureter resolved. In the harbor seal, the stone cluster was observed to fragment and was not visible on the post-operative computed tomography scan. The seal had gross hematuria and a day of behavior indicating stone passage but overall, an uneventful recovery. BWL and ultrasonic propulsion successfully relieved ureteral stone obstruction in a geriatric dolphin and reduced renal stone burden in a geriatric harbor seal.
To date, published comprehensive pathology investigations documented in Steller sea lions (SSL; Eumetopias jubatus) are from free-ranging populations, whereas health data from those under professional care in aquariums are currently lacking. A retrospective review of gross and histopathologic reports of SSL under human care in North American aquariums from 1979 to 2021 (n = 20) was performed. Associations between age, sex, or birth origin (born in aquariums versus the wild) with cause of death (COD) and comorbidities were explored. Age was significantly associated with development of endocrine organ pathology (P = 0.011). A relationship between age and both cardiovascular and ocular disease was suggested by the data, but did not reach significance (P = 0.058). Ocular disease was significantly associated with being born in aquariums (P = 0.022). The most common COD was neoplasia (n = 10), which was significantly associated with aged animals (P = 0.038). Less frequent COD included sepsis (confirmed, n = 2; suspected, n = 3), cardiomyopathy (n = 1), clostridial enteritis (n = 1), Sarcocystis spp. (n = 1), complication secondary to sedation (n = 1), and unknown (n = 1). This is the first report documenting the high prevalence of neoplasia in SSL, with tumors found incidentally in three individuals, frequent metastasis (10/13, 77%), and many cases of multiple primary malignancies (6/13, 46%). These data expand upon the current understanding of disease in SSL, highlight this species' predisposition to neoplasia with increasing longevity, and underscore the need for heightened screening in aged animals, which may ultimately serve to elevate the care of SSL under professional care in aquariums.
