ENG302:N14
2/27/03
The weather was almost perfect, and if not for the sights and sounds of the city, I'd have thought I was in California again. Bright sunshine, clear skies, and temperatures hovering around the low 70's welcomed me as I emerged from the Adams-Morgan metro and made my way up Connecticut Ave towards the Smithsonian National Zoological Park in northwest Washington DC. It had been a couple of years since I had visited the National Zoo and this was the first time I ventured there with a specific purpose -- to observe the California Sea Lion.
As a child growing up in southern California, it was not uncommon to see large aggregations of sea lions, lounging amongst the rocks and surf of Palos Verdes, far removed from the crowds of surfers, swimmers, and sun worshippers that populate vast stretches of the California coastline. These coastal mammals, known as Zahphus californianus, are locally abundant along the coasts of California and Baja California, but can be found as far south as Mazatlan along the western coast of Mexico, and as far north as the coasts of British Columbia. As I approached the sea lion exhibit at the zoo, I took note of the site construction which was built relatively similar to the rocky shorelines of California where sea lions congregate.
A large pool runs north to south along the western edge of the mock coastline with a smaller wading pool located in the center that is accessed from the north end of the pool. The pool widens into two slightly circular regions at both the northern and southern ends of the pool. Located in the center of these regions is a rocky protrusion upon which the sea lions may sit and swim around. It is here, at the northern end of the pool that I caught my first glimpse of Maureen swimming playfully around the center rock.
Maureen, one of two sea lions kept at the National Zoo was born in the wild in May 1977 and was acquired along with Norman, her male counterpart, from Marineland in 1978. Although it was somewhat uncomfortable, I settled down along the northern end of the exhibit where the zoo has constructed a small amphitheater for special events and demonstrations. Aside from the occasional passerby and screeching child, all was quiet on this weekday afternoon except for the subdued splashing and breathing sounds coming from Maureen.
According to the National Zoo's website, Maureen weighs approximately 200 pounds whereas Norman weighs in at a hefty 600 pounds. Upon my arrival, Norman was nowhere to be seen, although I would eventually get an opportunity to observe him late in the afternoon. Hence, I spent the majority of the afternoon watching Maureen.
It became obvious relatively quick that it would be difficult to reach any significant conclusions about true sea lion behavior as Maureen was alone, unlike in the wild where she would likely be found amongst an entire gathering of other females, pups, and large, male, territorial bulls, such as Norman. However, I was able to make good observations of her appearance and swimming style.
Light gray, Maureen looked like a torpedo as she streaked through the water. In the wild, sea lions are skillful "body surfers," gliding down the front of the waves either partially submerged or with their head just above the water, to come ashore. Obviously there were no waves at the zoo for the sea lions to surf on, but I became aware that Maureen did seem to be doing her best to simulate this ability.
For the most part, Maureen remained in the northern end of the pool, nearest my location, only venturing to the southern end every five to eight minutes, and only then for no more than a minute. This puzzled me for some time as I couldn't distinguish any difference between either location until I began taking notice of the apparent water currents that flowed in the pool. The water at the northern end seemed far more vigorous than the southern end, thanks to a series of pipes that jutted out along the edges of the pool, a short distance below the surface. Much like a backyard swimming pool, I began hypothesizing that this exhibit was not so dissimilar in that water was probably circulated and filtered back into the pool via these pipes. As a result, the water in the northern end swirled vigorously around the center rock and shoreline.
Over time, swimming patterns began to emerge that seemed to take advantage of these currents. Maureen, with her head above water would swim against the current along the shoreline, adjacent to the shallow wading pool, before turning and diving, streaking sleekly across the northern end of the pool with the current. At other times, when Maureen needed a boost, she used downward strokes of her forward flippers to increase her propulsion. Her hindflippers appeared to function similarly to that of a rudder during which she would extend her foreflippers as she banked through her turns. Although her habitat at the zoo is far removed from the coasts of California, the sea lion is clearly a fast and adept swimmer.
On land however, the sea lion doesn't appear nearly as graceful, although they are still deceivingly quick over short distances. As late afternoon approached, I had the opportunity to witness the zoo staff switch sea lions and observe Norman. The entire process took but a few minutes, and as 4:30 pm approached, Maureen seemed to be aware that something was about to happen. Located a short distance beyond the shoreline, and up a small hill is a semi-hidden staff area where the animals are kept while not on display. Maureen seemed very aware that a switch was about to occur, and as soon as she heard the distinct sound of a chain link fence rattling, she was immediately out of the water where she shuffled up the shoreline to the staff area.
Within moments, Norman was seen bounding down the rocks, and with a tremendous splash, all 600 pounds of this dark coated sea lion dove into the water. It was the only time during the entire afternoon that I had a chance to witness the sea lions' terrestrial movement. The primary mode of locomotion was driven by the foreflippers that were used alternately with the aid of the hind flipper to move forward. The result was a combination of lateral and forward movement with the body and limbs barely clearing the ground. Unfortunately, the entire sequence happened so fast with both Maureen and Norman, their heads swinging from side to side with each lunging step, that it was difficult to ascertain the precise motor movements of either one.
Following behind Norman after a few moments was a staff member, carrying a bucket full of dead squid. The staff member sauntered down to the waters edge where an eager and excited Norman watched and waited with mouth open wide; it was obviously feeding time. Amused by this, I couldn't help but think to myself that his behavior was uncannily similar to that of a domesticated dog.
Almost as though the staff member was reading my mind, she demonstrated that, in fact, these sea lions were domesticated and well-trained. At the flick of some unseen hand signal, Norman swam to the southern end of the pool and perched himself upon the center rock. Another snap of the fingers and Norman dove gracefully into the water and swam to the north end, performing three sleek porpoise jumps along the way before leaping from the water and perching himself on the center rock. Norman seemed quite pleased with his performance and was rewarded with a meal of fresh squid.
As the hour had grown late and the sun began to set, casting the viewing area into the cool shade of the early evening, I bade farewell to Norman who had established position in the shallow pool where he appeared quite content. As I crammed my way onto a crowded rush hour metro train, I realized that what I had witnessed was merely a small glimpse of the natural behavior of the California sea lion and that true understanding of them and their relationship with each other could only be ascertained from observations in their natural habitat. However, what could be determined were their unique, physical adaptations that allowed them to successfully survive in their native coastal environment. While domesticated to the point that Norman performed tricks for his meal, the deceivingly fast and sleek mobility of a 600-pound sea lion in the water demonstrated their obvious advantage for capturing prey. Certainly, the zoo is not a replacement for observations of sea lions made in the field, but with a little bit of time and patience, Maureen and Norman have a lot to teach us.