Sperm Whales Observation

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After enjoying a nice squid meal, Sapphire heads to her seaweed bed to take some final research notes before sleeping. She writes down her observations of the sperm whale's habitat, “Fin told me that sperm whales can be found all throughout the earth’s major oceans. From warm tropical climates in and around the equator, to the northern and southern polar hemispheres. I noticed that the females and their calves tend to prefer staying in warm climates in and around the equator throughout the year. Fin’s mother told me that the adult males travel to the colder climates during off-season and return back to the warmer climates during mating season. After asking more whales about their habitat, I learned that they are found in almost all marine…show more content…
She found a nice shell to sit in while she observed the whales around her. She began to write. “It appears the distribution pattern of sperm whales is cosmopolitan. This means that they are found everywhere around the world from the poles to the equator in all the oceans.” She brought out her checklist to see what was left. “Density dependent factors? Well the extensive whaling, especially after World War 2, may have decreased their size. The males that I’ve seen usually don’t exceed 18.3 metres in length and 51,000 kg.” She also wrote down risk of extinction, disease and competition for food under that category. “What’s next?” she asked herself. “Density independent factors? What’s the difference between this and what I just did? I’ll look it up.” After some research, Sapphire learned that density independent factors are things that affect the whole population in the same way, regardless of density. “Okay! So independent factors would include temperature (cold waters), water pollution (destruction of habitat), and low reproductive rate. All I have to do now is draw what the survivorship curve will look like!” She determined that sperm whales have a Type 1 curve, which is a convex curve, because most of them live to adulthood with mortality occurring at old age. She thought to herself “Legalizing whaling would change the survivorship curve to type 2 because whales would be likely to die at any age and that could result in species
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