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counts, and concentrations of sodium, potassium, glucose, Breaking New Ground:
and various hormones. Cetacean Welfare Study researchers Exploring Positive
wanted to create reference intervals and report on healthy
values for biomarkers found in the animals’ blood and feces. Indicators of Welfare
What are reference intervals and values? For example, The Cetacean Welfare Study used several novel indicators
said Miller, after looking at blood test results, a doctor may of animal welfare that are thought to be associated with
say your LDL cholesterol is “high” or your vitamin D is positive animal welfare and suggest an animal is doing
“low.” These conclusions are based on data collected from well. The study contributed science-based evidence that
blood tests performed on a large number of healthy individ- these indicators are potentially valuable tools to assess
uals. Medical experts determined a range of numbers and the health and welfare of dolphins.
an interval that indicates “normal” values for each biomark- Cortisol is a hormone found in an animal’s blood,
er. If your LDL cholesterol level doesn’t fall within the feces, and saliva that is produced at higher levels during
healthy range, you may be asked to take steps to correct it. times of anxiety or excitement. In the past, it was thought
When it comes to cetaceans, this information is either that the higher the concentration of cortisol, the less well
incomplete or does not exist—as is the case with Indo- an animal is doing. But Miller and other researchers have
Pacific bottlenose dolphins. Small sample sizes and other found that cortisol concentration may not be as good of
limitations of previous research studies produced numbers a measure of animal welfare by itself, mostly because it
with limited generalizability. doesn’t allow researchers to distinguish between a state of
temporary stress and the unhealthier state of chronic stress.
Miller added another indicator to the study—the ratio
Mountains of Data of cortisol to the hormone DHEA (dehydroepiandroste-

The Cetacean Welfare Study is unique because fecal samples rone). DHEA is associated with emotional resilience
were collected and analyzed for the presence and concentra- in humans. When combined with cortisol, DHEA
tion of glucocorticoid metabolites, which are hormones is potentially a better indicator of animal welfare—both
produced by the adrenal gland positive and negative states.
during times of stress, excitement, Miller also used a novel behavioral indicator—
or exercise. Compared with behavioral diversity, which is the range of natural or
obtaining blood samples, the species-specific behaviors an individual animal engages
collection of fecal samples is in. The list of these behaviors is different for each species.
less invasive and less stressful For dolphins, it may include behaviors such as interacting
for the animal, so samples can with other dolphins or enrichment, breaching, or tactile
be collected more often. behaviors. Compared with animals that display a narrow
Lauderdale coordinated the range of behaviors, animals that display a wide range of
amassing of enormous amounts behaviors are thought to be doing well.
of data from the 43 facilities. “We’re getting more and more data suggesting behav-
She sent each facility detailed ioral diversity is a positive indicator of welfare,” said Miller.
instructions on when and how “The results we’re seeing for dolphins, so far, seem to be
to collect the samples and other promising as well. It’s something Rita Stacey and the
data and helped secure permits SEVEN SEAS staff are now monitoring on a routine basis
required to send biological samples to make sure their animals are doing well.”
between countries. To ensure the animals were healthy, Giving animals in zoos and aquariums opportunities
they were thoroughly examined by veterinarians at each to engage in a diverse range of behaviors can potentially
facility during data collection. increase their welfare. Our animal care staff regularly
“All of the facilities put in a ton of effort to collect these monitors and updates our environmental enrichment
different streams of data,” said Lauderdale. “It reflects the program to make sure the dolphins have diverse
commitment of accredited facilities to continuously improve behavioral repertoires.
the welfare of animals in our care.”

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