White-Winged Ones.

McManatee — Sun, 11 Mar 2007 00:24:27 GMT

Last winter I had the amazing opportunity to study the Humpback Whales that winter at the Islas Revillagigedo. They're located about 400 km west-sw of the coast of Mexico, consisting of a small chain of islands including Isla Clarion where I spent the majority of my time. The whales start to arrive as early as November and stay as late as April. Males usually arrive first and leave last. Females give birth and introduce their young to life in the warm protected waters surrounding these islands. Before heading North to feeding grounds, calves must grow strong for the journey. They gain weight at an enormous rate nursing on the mothers fat rich milk, learn to breach, slap, and negotiate the water and its inhabitants. Most stay within the watchful eye of their mother-there seem to be the few hyper-active wanderers. Many mom-calf pairs are accompanied by an escort-an unrelated male. At first observation you would think that maybe they are related and are protecting their young-not exactly. Instead they are trying to father the next calf-constantly defending their identity as mom's current "boyfriend". Humpback females are one of the only mammals that can get pregnant almost immediately after giving birth and will most likely travel north in the spring with a new pregnancy. It's not easy being the stud. Males are continually defending their position often fighting off competitive groups of 10-20 aggressive males jockiing for position. Strategies are brutal. Males breach on top of each other-often landing with a chin full of barnacles, hold flukes down preventing dives, breath-holding competitions, throw "right hooks" with pec fins edged in barnacles. I witnessed several of these competitors surface minus their dorsal fins.Adrenaline packed pursuit, around and around the island-all female determined. Not only do they compete they sing beautiful, chilling, songs for hours. Why? No one knows. To attract mates, establish territories? Maybe just because they can. At 130 decibels the song vibrates your body, bottom of the boat, and travels enormous distances through the ocean's acoustic amphitheater. While on Clarion I was given the opportunity to get very close to these amazing mammals, both in and out of the water. Mom's and especially calves were often very curious, granting enormous trust in proximity to them. Knowing full well their ability to relocate you with a swipe of a tail or pec fin. Singers, in their floating, head down trance would also let you listen closely, vibrating sound waves through you toes up through your ribs, out the top of your skull. Providing recording opportunities and underwater video that can only begin to capture the powerful acoustics of their communication.

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White-Winged Ones.