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Baja Jones Adventures |
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During feeding, the gray whale appears to prefer using its right side to scour the bottom and find its food. This has been noted by several long time observers. To feed they gulp mouthfuls of mud from the bottom, then use the whiskery baleen as a filter to drain out the unwanted material. This leaves the amphipods stuck to the baleen inside their mouths. They then use their tongues to loosen the amphipods from the baleen, and swallow. During migration and while in calving areas, gray whales eat very little, although they occasionally will eat shrimp-like mysids or small fish at the surface. Thus the blubber they add during the summer feedings must provide energy for the remainder of the year. Many whales may go without food for 3, 4 or even 5 months! Recent research at Laguna Ojo de Liebre has shown that there are critters in the muddy bottom upon which the whales may feed. If you look at my Whaletails page, you will see several photos that I point out as characteristic of feeding whales. These photos were taken at Laguna Ojo de Liebre. I believe that at least some of the gray whales spend much time bottom feeding in the Mexican lagoons.
The gray whales courting ritual involves two males and one female Imagine this scenario. It is October, the weather is changing, a well fed 4 year old male gray whale is horny as all get out. He begins swimming south. Another male, maybe he's 12 years old, more experienced, 6 feet and 4 tons bigger than the first male. Still, he gets the urge too, stops munching potholes in the muddy bottom and begins slowly swimming south. Somewhere off the coast of Oregon a barnacle clad 6 year old female meets our 4 year old male. They begin swimming side by side. She too is feeling frisky. As the two swim along, mile after mile, side by side, there is a playful rubbing of one body against another. This begins to stimulate the hormones. Just north of Monterey Bay the pair are joined by that older, more experienced bull male. He swims along by at her opposite side. Now there's three horny whales swimming south and a whole lot more rubbing of barnacle against barnacle. The hormones are really beginning to take control. By the time the trio passes Ensenada, there isn't much on their minds besides completing this 5000 mile mating ritual. They rub, they swim, they roll against one another, all the time slowly working their way south. Sometime in January the trio finally reach the warm ocean waters between Cedros Island and the mouth of Laguna Ojo de Liebre. They don't enter the lagoon, but rather linger outside, brushing harder against one another. Each male is sure he will be the chosen one. She plays coy right up until the last moment. Then, when nature says it is finally time, our solitary female rolls to one side. Is it the left side? or to the right side? No one knows, until that ultimate moment when the lucky male discovers he has been chosen. The loser, rather than hanging his head and chugging off into the sunset, must now linger on the other side of the female and help support her while the winner finishes impregnating her. An interesting and unique feature of this mating trio, is the lack of aggression on the part of the males. They have never been seen to fight or engage in ritual aggression. They are truly a unique animal ! The gestation period for gray whales is 11 - 13 months. The gray whales usually give birth in the Baja lagoons, including Laguna Ojo de Liebre and Laguna San Ignacio, although some whales give birth during their southward migration, before they reach the lagoons. I theorize that as the species population has increased, so too has the number of births occurring during the southward swim. Giving birth early is not a survival characteristic. This may be why so many youngsters, such a J.J., are found without mothers along the Southern California shoreline. It is possible the mothers abandon the newborn baby if it is born too far north. Another theory is that in years past, Gray Whales could stop in Los Angeles or San Diego to give birth. There is now so much traffic and noise that these areas are no longer feasible for the whale to use as birthing grounds. I tend to put my faith in this second theory. Rather than abandoning the newborn, the female is just not able to assist it to swim in the deep ocean outside of the bays and lagoons. The warm temperature, shallow depth, and limited access to the open sea, make the Mexican lagoons the ideal places for these marine mammals to mate and to give birth. The shallow water and narrow entrances are not conditions that Orcas care for. The Orca uses speed when hunting and pursuing prey and speed is hard to obtain in the extremely shallow lagoons. The gray whales have the advantage over the orcas when inside the lagoons! The pregnant females and those with calves concentrate in the inner lagoon, furthest from the sea. The majority of births occur between from January to the end of February. The newborn gray whale is around 15 feet long at birth, weighs around 2000 pounds. The very young calves stay very close to their mothers during the few months of life. In some cases, another gray whale called an auntie helps the mother during birth. The auntie may help hold the mother above water. She may also assist the newborn to the surface for its first breath. The warmer waters of Mexico help newborns to conserve body heat. They are born lean and relatively blubberless. The calves nurse for around 6 months, during which time the mother provides up to 50 gallons of milk each day, containing 53% fat. Calves may gain 60 to 70 pounds daily, building up blubber for their trip north. The whales with calves prefer the inner part of the lagoon during the first weeks following the birth. Then as the baby grows the pair venture into the middle of the lagoon. To gain strength for the 5,000 mile journey, the calves practice swimming against the currents in the lagoons. It is common to see dozens, even scores of mother baby combos slowly swimming against the incoming or outflowing tide. This exercise is necessary to prepare the youngster for the coming 5000 mile northward journey. The whales with offspring leave the interior of the lagoons when the calves are strong and can swim without problems. These days there has been an increase in the number of packs of Killer Whales waiting for the mothers and babes to begin their northward journey. There has been a major increase in the quantity of so called wild Orcas. That is, those that follow the whale migration route, instead of hanging out in organized families in the the northern waters, eating fish, and just chumming around with the rest of their family group. The wild Orcas form a 5000 mile long gauntlet through which the young calve must now travel just weeks after their birth. Thousands of gray whales arrive each year in Baja California. Approximately 900 gray whales visited Laguna Ojo de Liebre during the 1995 season. In 1996 that number increased to 1,270 and in 1997 1,575 gray whales visited Laguna Ojo de Liebre. Laguna San Ignacio is the second most frequented site, with 326 whales visiting the lagoon in 1998. Although gray whale births often occur in the lagoons, most whales that migrate to Baja California never enter the lagoons. As the overall population has increased, so too has the frequency of sightings increased. As well, the area of gray whale sightings has broadened so that now there are grays spotted as far south as Cabo and even around into the Gulf of Baja waters. The contents of this site, both the photographs and the editorial copy, are copyright Keith E. Jones 1998. This means you cannot use the photos without permission. However permission is hereby granted to any individual who wishes to use photos or editorial copy as part of an educational report or study, as long as you list this publication in your bibliography. For commercial and editorial uses contact me by email and I will respond promptly. | |||||||||||||||||||||||||||||||||||||||||||||||