Marine Mammals – Part 3

The killer whales belong to the oceanic dolphin family and are highly social. May be like our Mamis? Read on and then you can’t stop admiring them, I mean the killer whales! 

The MB showed the photograph of 137 and pointed at the killer whale. The picture had a curved dorsal also had a distinct fluke. She explained to us the distinct color patches: black back, white chest and sides, and a white patch above and behind the eye and how they can be recognized from their dorsal fin and tail fin.

They are indeed a chatter box
The killer whales like to communicate and depend heavily on underwater sound for orientation, feeding, and navigation. They produce three categories of sounds: clicks, whistles, and pulsed calls. Clicks are believed to be used primarily for navigation and discriminating prey and other objects in the surrounding environment, but are also commonly heard during social interactions.

Males are momma’s boy for life
Killer whales are notable for their complex societies. Only elephants and higher primates, such as humans, live in comparably complex social structures. Males live with their mothers for their entire lives. These societies are based on matrilines consisting of the matriarch and her descendants who form part of the line, as do their descendants. The average size of a matrilineal is 5.5 animals. The killer whales are also found to adopt orphaned calves and care for them throughout their life. Because females can reach age 90, as many as four generations travel together.

No incest in their world
Males separate for only a few hours at a time, to mate or forage and come back to their mothers. Closely related matrilines form loose aggregations called pods, usually consisting of one to four matrilines. Unlike matrilines, pods may separate for weeks or months at a time. DNA testing indicates resident males nearly always mate with females from other pods.

Activities in water
The killer whale activity consists of foraging, travelling, resting and socializing. Killer whales are frequently active at the surface, engaging in acrobatic behaviors such as breaching, spyhopping, and tail-slapping. These activities may have a variety of purposes, such as courtship, communication, dislodging parasites, or play. Spyhopping, a behavior in which a whale holds its head above water, helps the animal view its surroundings.

 

But they are apex predators
These whales are regarded as apex predators and feed on salmons and other varieties of fishes. They also go for mammals such as sea lions, seals, walruses, and other smaller whales in the pyramid. There have been a few instances where they have tried to kill humans.

They are intelligent too
They are also regarded as the most intelligent species among marine mammals. Killer whales imitate others, and seem to deliberately teach skills to their kin. Adults sometimes pull seals off the shoreline, and then release them again near juvenile whales, allowing the younger whales to practice the difficult capture technique on the now-weakened prey. The killer whales use dialects and pass on other learned behaviors from generation to generation, thereby forming a culture.

Yet their population is shrinking
They may be apex predators in the marine ecosystem, but we are sitting on top of them in the ecological pyramid and creating havoc to their world. Pollution from large-scale oil spills, letting in untreated sewage, chemical leaching, and disturbance caused by noise and conflicts with boats are currently the most significant worldwide threats to the marine mammals. The impact of sonar waves on killer whales is potentially life-threatening.

I don’t care even if we don’t have such rides along our coast, but atleast let us not pollute their world and kill them for food and other monetary gains.

Marine Mammals – Part 2

 

The marine biologist confirmed that the passenger was indeed right and the v-shaped shower came from the blowholes on the top of the whale’s head and that he was a lone male traveling back from the Gulf of Mexico after the breeding season and feeding crustacean rich waters along the coast of Monterey.  She looked through her binoculars to confirm the species. She spotted the gray-white patterns and scars left by parasites which drop off in its cold feeding grounds and confirmed it to be a gray whale.

Gray whale is an endangered species on the west coast and there less than 200 surviving today. They travel approximately120 kms/day and cover 16,000-22,000 kms during the annual migration. They are spotted between mid-December to early January at Monterey during their journey South and found along with their calves between March and May on their journey back North.

Bio-magnification

Biopsy of Whale blubber found high levels of PCBs (Polychlorinated biphenyls) in their body. PCBs are found in flame retardant chemicals used in lot of upholstery and home fabrics have found their way into the ocean and into the marine ecosystem. The marine biologist pointed out that whale calves were found to have high levels of PCBs in their system and many of them died young. She also confirmed that the PCB levels were found to decrease as the off springs increased. So, more the offspring better was their chance of survival.

We were in the middle of the Ocean and the marine biologist (MB) asked the captain to shut off the boat. The waves rocked the boat back and forth while the MB asked us to keep a watch out of other cousins of the gray whale. Bala found warmth under the sun, I took a nap inside, not sure if it was sea sickness or exhaustion. I suddenly woke up to a loud noise, did something happen to the boat or did they spot something exotic in the ocean? Come along...lets go deeper.

The MB spotted a humpback whale and when she pointed the crowd towards its direction the entire crowd went gaga watching the whale taking a plunge and showing off its tail fin. While we waited for another show, the MB shared more information about its social behavior and singing traits.

Unsociable but singing humpbacks

 

The humpbacks social structure is loose-knit. Typically, individuals live alone or in small, transient groups that disband after a few hours. These whales are not excessively social in most cases. Groups may stay together a little longer in summer to forage and feed cooperatively. Longer-term relationships between pairs or small groups, lasting months or even years, have rarely been observed. Some females possibly retain bonds created via cooperative feeding for a lifetime.

Both male and female humpback whales vocalize, but only males produce the long, loud, complex "songs" for which the species is famous. Each song consists of several sounds in a low register, varying in amplitude and frequency, and typically lasting from 10 to 20 minutes. Humpbacks may sing continuously for more than 24 hours. Whales within a large area sing the same song. All North Atlantic humpbacks sing the same song, and those of the North Pacific sing a different song. Each population's song changes slowly over a period of years without repeating

Before 1966, the humpsbacks were almost at the verge of extinction, and subsequent protection laws and enforcement has helped to improve their population. There are now close to 80,000 humpbacks seen along the coast of Australia, New Zealand, US, Canada and South America.

Three hours had elapsed into the trip, and by then some of the passengers were excited to catch another species in the top of the marine pyramid – the killer whale, while some passengers got sick from staying out long in the rocking boat went in for a nap. Suddenly the MB yelled 137 and pointed passengers towards eleven o’clock. What do 137 refer to? Was she referring to serial killers? Did we get a glimpse of killer whales? Come back next week.

Vist the link to view the pictures: https://picasaweb.google.com/108289564546757100555/MontereyBay#

Marine Mammals – Part 1

 

The Indian peninsula (surrounded by ocean on three sides) and our rich coastline (over 4671 miles) are often mired in controversy than pride. Time and again we've read stories about Sri Lanka and Pakistan army taking away our fishermen for trespassing their waters and Olive Ridleys by getting caught in the trawler rudders and meeting their fate during the breeding season. The recent incident where the Italian marines opened fire at Kerala fishermen mistaking them for pirates the relationship between Italy and India dived into troubled waters.

Are oceans really calm waters or have we turned them into troubled waters making death and imprisonment along the Indian peninsula? To this Interesting question and I found a few parallels in the marine world during my recent trip to San Francisco, California, US.

My friend Bala, took me on take a boat ride along the Monterey Bay. During the boat ride, the two marine biologists onboard explained the behavior of mammals in water, their aggression and territorial fights, their migration patterns, and the impact of human behavior along the 870 mile Californian coastline.

We boarded the boat at 9 am, the sky was blue, the sun was shining bright and gentle breeze was blowing towards the shore. To our surprise we were welcome by two friendly dogs who wanted to play and be petted, but was restrained in the upper deck L of the boat. I had no clue how my body was going to react to the constant movement of the boat, high velocity cold wind and but was anxious to explore the marine world. Once we began the journey, I realized that Bala was damn right to get me a monkey cap at the Wharf. The thick layer of acrylic covered my bald pate and kept my ears warm. And we stood in the sun to keep ourselves warm.

Within 50 meters from the shore, we spotted sea lions, otters, few other sea birds, seagulls included. The mammals were basking in the warm sun, while the birds were busy collecting sea weeds to build their nest. While we humans fell trees and mine below the ground to get raw materials to build our homes, these birds were merely using what is easily available in the nature without causing any environmental hazard. Though some of them migrate across the globe and build new homes to breed, they still keep it small, simple, sturdy and eco friendly. There is so much to learn from nature and its creations.

Soon the shore looked very distant and suddenly the marine biologist asked us to look to the right of the boat. There were a dozen dolphins jumping out of the water and expressing their joy, excitement and social skills. The marine biologist explained that the dolphins were closely related to whales and porpoises and are the most intelligent animals in the marine world.

Sight, touch and smell: Most dolphins have acute eyesight, both in and out of the water, and they can hear frequencies ten times or more above the upper limit of adult human hearing. The dolphin's sense of touch is also well-developed, with free nerve endings densely packed in the skin, especially around the snout, pectoral fins and genital area. However, dolphins lack an olfactory nerve and lobes, and thus are believed to have no sense of smell. They do have a sense of taste and show preferences for certain kinds of fish.

Social skills: Dolphins are often regarded as one of Earth's most intelligent animals. Dolphins are social, living in pods of up to a dozen individuals. In places with a high abundance of food, pods can merge temporarily, forming a superpod; such groupings may exceed 1,000 dolphins. Individuals communicate using a variety of clicks, whistle-like sounds and other vocalizations. Membership in pods is not rigid; interchange is common. However, dolphins can establish strong social bonds; they will stay with injured or ill individuals, even helping them to breathe by bringing them to the surface if needed.

Slowly the boat ventured into deep waters of Pacific Ocean and the marine biologist was hopeful in sighting some whales today. And at a distance a fellow passenger spotted a shower in the middle of the ocean and asked the marine biologist to take a look towards two o’clock position. Was it a grey patch of cloud? Did we get lucky? Come back next week for more interesting stories, sightings and also find out if I lasted the entire trip.