seen some miracles of motivation. We are convinced
that friendship therapy contributes to the recovery
or at least stabilization of sick rabbits.”
One particularly stressed-out 8-year-old rabbit,
Jefty, began developing a physical manifestation of
that anxiety, according to Harriman. After his mate
died of cancer, Jefty began to chew at his fur and de-
veloped bald patches. A veterinarian examined the
rabbit and found a gigantic hairball lodged in his
stomach; the vet thought that it was unlikely that
the mass would pass on its own (because of Jefty’s
continued chewing) and recommended surgery.
Harriman started the animal on a variety of hair-
ball medications to prepare him for surgery, but she
tried another approach too: she introduced Jefty to a
10-year-old rabbit that had also just lost her partner.
After Jefty spent a few days with the new rabbit
companion, his stress-induced chewing slowed and
Harriman canceled the surgery.
Although an x-ray showed that
the furball was still in his sys-
tem, it was shrinking. “I won’t
try to claim that getting happy
cured a furball,” Harriman
wrote. “But I will claim that it
gave Jefty a reason to eat the hay
and greens in front of him. He
had someone to dine with and to
share his pineapple cocktail.” In
the following weeks, Jefty com-
pletely stopped his fur-chewing,
and the hairball shrank even further. By addressing
the cause of Jefty’s lingering stress (the loss of his
partner), Harriman seemed to have been able to re-
solve his physical stress response.
AQUATIC ANXIETY
in addition to various natural threats,
wild animals must cope with human-induced pres-
sures. Whales, the largest animals in the world, con-
tain a history of the oceans—and the stress people
have caused them—in their ears. Whales accumulate
a solid plug of wax in their ear canal, some grow-
ing up to 10 inches long. The wax changes colors
during seasonal migrations, creating alternate light
and dark bands. Like tree rings, these bands allow
researchers to estimate a whale’s age, and they also
allow them to analyze the substances and chemi-
cals that have coursed through the whale’s body. In
a study published in 2018, Stephen Trumble and
Sasha Usenko from Baylor University took earplugs
from humpback, fn and blue whales from both the
Pacifc and Atlantic Oceans from 1870 to 2016 and
used the wax to determine the whales’ cortisol lev-
els. “This is the frst-ever study to quantify tempo-
ral stress patterns in baleen whales,” Trumble said.
“While the generated stress profle spans nearly 150
years, we show that these whales experienced survi-
vor stress, meaning the exposure to indirect effects
of whaling, including ship noise, ship proximity and
constant harassment, results in elevated stress hor-
mones in whales spanning vast distances.”
After moratoriums on whaling were introduced
in the mid-1970s and harvests fell by 7.5% annu-
ally, cortisol levels in earwax dropped by 6.4% a
year. But after cortisol dwindled to essentially neg-
ligible levels, they began to increase in the ensu-
ing decades. “From the 1970s through the 2010s,
whaling counts were report-
edly zero in the Northern Hemi-
sphere, but mean cortisol levels
steadily increased, with recent
peaks reaching near the max-
imum levels observed before
whaling moratoriums,” said
Usenko. The increase was slow
at frst but became more drastic
in subsequent decades. Accord-
ing to Trumble and Usenko, this
rise likely has to do with unusu-
ally high ocean temperatures as
well as other man-made stressors, including from
submarines entering their domain and from ingest-
ing ocean pollutants such as mercury and pesticides.
According to a 2012 study, noise from ships
can lead to chronic stress in whales, which is det-
rimental to their health. “We showed whales oc-
cupying oceans with high levels of ship noise have
a chronic stress response,” Rosalind Rolland, who
led the study, told the Guardian at the time. “We
knew whales changed the frequency of their calls
to adapt to the ship noise, but this work shows it is
not merely an annoyance—it is having a physical ef-
fect.” According to Rolland, this type of long-term
stress can cause profound depression of the immune
system, which puts the whales at risk of diseases. It
also can limit their reproduction. The northern right
whales that Rolland studied are one of the most en-
dangered species of whales, with only about 450 es-
timated remaining worldwide.An anxious
pet does not create
a stressed-out
owner, but the
reverse does seem
to be true.