This rare glimpse of a pregnant bottlenose dolphin makes you hope that water really does make everyone feel weightless.
Privileged people have personal assistants these days, but here in the United States we rarely encounter those classic personal assistants to queens and princesses known as ladies-in-waiting.
More like royal companions than servants, ladies-in-waiting nonetheless carried out a number of quite varied royal duties. Their duties often included exceptional skills in etiquette, conversation, dancing, riding, art and other royal pastimes as well as secretarial and management duties. In other words, ladies-in-waiting were particularly accomplished at waiting on their superiors.
A recent episode at sea suggested we might consider another kind of lady-in-waiting: a pregnant female.
Five dolphins were heading toward in a deep channel that leads to John’s Pass and the mighty Gulf of Mexico beyond. The dolphin without a calf, J, swung into a nearby narrow channel that branched off like a side path in the woods to search the seawalls for something to eat. The other four dolphins started to follow her, but turned around and milled about in the deep channel, swimming without going anywhere.
While they waited for J to finish her seawall search, the quartet began to socialize. This was unusual because they were two mom-calf pairs, Courtney with her calf Cutlass and ZZ with her calf Zulta, and mom dolphins aren’t particularly playful.
But today they twisted around each other and even tossed a bit of floating flotsam. Suddenly one of the moms launched out of the water, carved a graceful bow and vanished back into the water, revealing that she was very pregnant.
An aerial view of a dolphin lady with a bulging belly is a rare and wonderful picture because you can’t look at a dolphin swimming by your boat and tell that she’s pregnant. This particular “lady in waiting” was either Courtney or ZZ. To tell who she was, I needed to see the notch and nick pattern on the trailing edge of the bowing mom’s dorsal fin, the fin on the dolphin’s back that sticks out of the water when a dolphin surfaces to breathe, which is how field biologists tell dolphins apart at sea.
But identifying the lady with the bulging belly was not easy. She leaned a little to the side, which partially cloaked her dorsal fin pattern. Worse, the sun hit the wet fin at just the right angle to eclipse her dorsal fin pattern in bright beads of light. On top of that, both Courtney and ZZ have subtle dorsal fin patterns anyway. The give-away to the bowing mom’s identity was the scar on her tailstock: the bowing mom with the bulging belly was ZZ.
ZZ’s picture show us what a pregnant bottlenose dolphin looks like, but doesn’t reveal how much longer she’ll be waiting in her year-long pregnancy. I’ll be a lady-in-waiting until the calf is born to figure out how pregnant ZZ is in this picture. Unfortunately, the odds are that I’ll be waiting a very long time.
That’s because ZZ is an occasional visitor to our local waters. We identified her in 2004, but we’ve only seen her six times in the past nine years. Curiously, she was one of the dolphins who appeared in our local waters more often during than before or after the recent five-year construction project replacing the previous John’s Pass Bridge that was completed in 1971. If ZZ stays true to habit, we won’t see her again until 2015!
One of the surprises in ZZ’s pregnant picture is that it is so obvious that she’s pregnant. It is not a good idea, and therefore not a standard, for mammal moms in nature to reveal that they are pregnant. And it definitely doesn’t pay for a female to show that she’s “heavy with child” because it advertises her vulnerable condition, which in turn attracts the wrong company.
At birth, ZZ’s calf will weigh around 45 pounds, which is about 10 percent of mom ZZ’s 450 pounds of body weight. Human pregnancies are closer to half that - a 7.5-pound newborn born to a 130-pound mother accounts for about 5 percent of mom’s body weight.
As an adult female bottlenose dolphin, ZZ is 7 to 8 feet long. Her calf will be about four feet long at birth, which is virtually half as long as ZZ! In striking contrast, a human baby who is 17 inches long at birth is merely a quarter as long as its proud 5-foot-6-inch mom.
Dolphins and humans grow at considerably different rates, and it starts with mother’s milk. Not surprisingly, there is a dramatic difference in mother’s milk between dolphins and humans. Dolphin milk is rich with proteins and fats - 33 percent fat, 7 percent protein, traces of lactose and 58 percent water. Protein determines growth rates but producing milk that is only half water not only helps the baby grow rapidly, it is also one way that dolphin moms conserve their own precious water supplies.
In contrast, human milk is mostly water with few calories because it has little fat and protein, but explains why we love cheese and sugar - 3 to 5 percent fat, 1 percent protein (whey and casein: casein is what makes cheese so lovable), 7 percent carbohydrates (mainly lactose, which is the principal sugar of human milk) and 90 percent water.
But there are some striking similarities. Both dolphins and humans sometimes share the task of nursing, which is very unusual in the animal kingdom but relatively common among humans in the form of wet-nursing. Say, that’s another kind of lady-in-waiting.
Dr. Weaver studies wild dolphins under federal permit 16299, National Oceanic and Atmospheric Administration. Send her an email at firstname.lastname@example.org or visit her website www.dolphinsuperstore.com. NOAA advises anyone who sees a stranded dolphin in the Gulf of Mexico to call 877-942-5343 or 877-433-8299.