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A Closer Look at Argentinean Patagonia Date: 2004-01-30 WildlifeSAIL NEWS LETTER 27 January, 2004 Summary: 1. 5 NEW log reports (No. 60 - 64) 2. NEW Underwater Video of Dolphins swimming with catamaran 3. NEW Educational Module: CLASSROOM work covering Natural Resources and Biodiversity on Patagonian Atlantic Coast 4. NEW Interview with WCS Scientist Claudio Campagna: "Seagulls Change Whale Migratory and Reproductive Behavior - What Is the Human Factor?" -by Kate Hagerman and JF Thye ********************************************** ********************************************** 1. See www.wildlifesail.org for log reports ********************************************** 2. Visit www.wildlifesail.org Video Gallery. We were able to get this underwater footage when a large group of hyperactive dolphin visited us off the south Brazilian coast. ********************************************** 3. Education (click on Education in the www.wildlifesail.org menu bar): WildlifeSAIL visits Argentinean Patagonia. This WCS sponsored Educational Program discusses Natural resources and Biodiversity on the Patagonian Coast. Included are interactive maps with theoretical approaches, activities and proposals for CLASSROOM work that focus on the wild Patagonia habitat. ********************************************** 4. Seagulls Change Whale Migratory and Reproductive Behavior - What Is the Human Factor? We know uncontained human garbage in open air disposal sites has unaesthetic consequences. But can you imagine the demise of whales due to the inability of humans to cover their trash? That is exactly what we learned while surveying the marine population at Playa Colombo, Peninsula Valdez, Argentina with WCS scientist Claudio Campagna. We encountered 20 Southern Right Wales. I was awe struck as mothers and calves curiously approached us. Their movements were graceful and affectionate. The calves followed the mothers closely, occasionally rolling their silky torsos, splashing a flipper playfully. The Southern Right Whale averages 56 feet in length and weighs 2,000 pounds. The body is black with white ventral patches and a large rotund shape, and the broad back lacks a dorsal fin. Callosities cover the head occurring in approximately the same places that facial hair grows on human males. Off Argentina, southern Rights have been observed "sailing," a behavior in which they raise their tail flipper in the air at a 90 Degree angle to the wind and "sail" downwind, often returning to their starting point to repeat the behavior.* The Rights came close to the boat. We filmed and listened to their brilliant sounds. I was astonished to see gaping holes along their backs. I asked Claudio Campagna what caused them. In a bewildered tone he said, "The seagulls are eating the whales alive" while pointing to a sea gull pecking the skin off of a whale's back. "They eat their blubber once they tear through the skin." The behavior is recent, since the human population boom in the area. 15 to 20 years ago the gulls were just eating the skin that naturally peeled off of the whales into the water. Only in the last 10 years have they attacked the whales directly. Claudio elaborates, "This is cultural evolution, not natural selection.** The seagulls look at each other and learn the behavior by observation. The whales are in agony. When the whales are disturbed their behavior changes. Cows (female whales) stop nursing their calves, who are dependent on their mother's milk, to escape the gulls. They dive underwater and arch their backs. They swim away from places where seagulls attack them, which may have an effect on the places they select for breading. Some whales have 15-20 holes that are a few centimeters deep. Gulls should be considered predators. It has to be stopped." "How are humans linked to the seagulls eating the whales alive?" I asked. "The increase in the gull population is due to the humans making food available to them in open garbage dumps. There are three large garbage dumps in the area: Puerto Madryn, Rawson, and Puerto Piramides. In the Puerto Madryn garbage dump the gulls dine on fish remains from the local processing plants. The only solution is to close the garbage dumps (meaning cover them) and remove the gulls that know the behavior. In turn, we humans have turned seagulls into whale predators." "What are the long term effects?" He replies, "The gulls could transmit diseases, particularly if they are the same gulls eating at the garbage dumps. The pain the gulls inflict on whales and the whales' effort to escape the gulls is causing change in their natural movement, altering migration and nursing behaviors. We also have to take into account that the movements required to escape the gulls are energetically costly to the whales; the whales increase their speed of travel and so their migration patterns change. It is evident now that garbage dumps are a health issue for people as well as the most important tourist industry in this area, the whales." I ask what is the status on covering the garbage dumps. He says bleakly, "Everyone knows about the problem but at this time nothing is being done. It is too costly for the government. We would have to get an international loan to the Provence Chubut (the region)." * Whale facts from: A Guide to Marine Mammals of the World. National Audubon Society. ** ("Natural selection" is a method in which animals adopt behavior over very long periods of time, over many generations. The behavior is naturally imposed upon a population of animals because it leads to a higher survival and reproductive life for that animal population. Animals who don't innately produce the behavior die and are not selected by nature to continue breeding successfully. In other words, mother nature selects which behavior is a good balance for the environment. In "cultural evolution" animals learn to behave in a certain way by watching each other. Cultural evolution can happen in a relatively short period of time and is not dictated by a natural environmentally healthy course of selection over long periods of time. Cultural evolution can be devastating in the long term for an animal population, whereas natural selection is a natural evolution that leads to survival.) - With respect, Kate Hagerman and JF Thye P.S. Many thanks to Claudio Campagna for welcoming the WildlifeSAIL Team to document his research on Peninsula Valdez and coastal Argentine Patagonia. ********************************************** For more information and to track the WildlifeSAIL science adventure, visit us on-line at www.wildlifesail.org, or email us at info@wildlifesail.org ********************************************** To unsubscribe from the WildlifeSAIL Newsletter please: 1) Email unsubscribe@wildlifesail.org 2) Please ensure that your email you wish to unsubscribe is listed as your Return Address 3) In the Subject row please type: UNSUBSCRIBE |
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