Salmon
What species would travel over 2000 miles just to have young and then die? It has been said that anyone who has not seen a wild salmon has not seen what a fish should be. Salmon was the common name applied to fish characterized by an elongated body covered with small, rounded scales and a fleshy fin between the dorsal fin and tail. In this paper I will be discussing history of studying salmon, the life cycle, spawning and mating behaviors; which has much to do with the total reproduction of salmon.Salmon were studied earlier than some may think. Experiments were done by men that date back to the mid-1600s. These experiments involved catching salmon in fresh water, tagging them, and then catching them again when they return to the same place, around six months later. These experiments were doubtful and it was not until the beginning of the 1900's that proof was available that the salmon returned home. (Shearer) Although usually drab in color before the breeding season, which varies with the species, members of the salmon family develop bright hues at spawning time. The male, during this mating season, usually develops a hooked snout and a humped back. "In many diverse taxa, males of the same species often e
Those born in the upper reaches of the Columbia River's tributary stream, the Snake River, travel more than 1,000 miles inland to lay their eggs and fertilize them, roughly one fourth of the distance across the United States. These fish belong to the salmon family. One male dominated the paternity during polygamous spawnings, fathering more than 80% of the progeny in a single nest. With the completion of spawning, their lives soon come to an end. Thus, male fertilization success can be influenced by a variety of factors, including sperm precedence, male size, and spawning history. However, a small proportion of males release a pheromone that attracts other males, as though they were females. Ecology and Management of Atlantic Salmon. The spawning ground of these fish is usually a rapidly flowing, clear stream with gravel and rocks on the bottom. Typically, fewer than 10 per cent of spawning Atlantic salmon return to the ocean, with most of these being females. ' In competitive mating trials, she-males mated with females significantly more often than did normal males, demonstrating not only reproductive competence but also a possible selective advantage to males with this female-like pheromone. Among the fishes, bluegills and salmon (and probably many others) have female-appearing males competing with normal males. The males are constantly teare"In many diverse taxa, males of the same species often exhibit multiple mating strategies. Back to Table of Contents An adult female salmon can lay upto 15,000 eggs, depending upon her size.
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