ALASKAN SALMON RUN

     Part of this June and July, I have been watching many thousands of sockeye salmon, by live cameras and our home computer screen, leap up a six foot falls on Brooks River in Katmai National Park in southwest Alaska.  The salmon left the Pacific Ocean, where they grew large, to swim upriver to the shallow, rock-bottomed streams, where they hatched, to spawn.  As they push upriver, their grayish body scales change to red.  And these millions of sockeye salmon are parts of several food chains, a few of which involve brown bears, glaucous-winged gulls, bald eagles, gray wolves and ravens, which are clearly visible on our computer screen. 
     About 2,200 brown bears live in Katmai Park, and many, if not all, the adults catch and eat sockeyes during that fish's run upriver.  Bears snare salmon all along Brooks River, including below its falls and just above them.  Adult male bears get prime places at the falls where concentrations of salmon are thickest.  And some salmon accidentally jump right into bears' mouths at the top of the falls, when those fish attempt to leap the falls.  
     Female brown bears, with one to three cubs each, take lesser positions along the river because they are smaller than mature males, and they need to defend their young against male bears: Therefore, they stay away from them.  But whatever positions brown bears take along the river, and in the river, they can easily see the salmon rapidly swimming upstream, which helps the bears catch many of those large fish.  
     Brown bears are wasteful feeders, as I saw on our computer screen.  It looked like many of the bears stripped off and only ate the fatty skin, which they apparently crave to put on pounds for the coming winter's sleep.  But they didn't consume much else on each salmon.  They dropped the dead fish in hand on the shoreline or in the river and caught more sockeye, which they only party ingested.  After several days of several bears catching and eating only parts of each fish, the river and shoreline were littered with dead salmon, seemingly a waste of lives and resources.
      But the dead, torn apart salmon were not wasted because of the scavenging gulls, eagles, ravens and wolves feeding on the washed-up fish.  Scores of large, stately glaucous-winged gulls, a species of the west coast of North America, feed on the many dead salmon on the river's banks.  These are lovely, and adaptable, gulls that show up wherever there is abundant food.  The bears benefit the gulls because they provide large fish as food, fish too big for the gulls to catch themselves.    
     I saw a few bald eagles scavenging dead sockeye salmon along Brooks River, as eagles do elsewhere.  These large birds also catch live fish in their sharp claws, but not sockeyes because those fish are too big for eagles to handle.      
     And I saw one each of raven and gray wolf also scavenging dead salmon on the river's banks, fish killed by brown bears.  Both these species kill live prey when they can, but neither ravens or wolves are  above scavenging dead animals, wherever they may be.  
     It was thrilling to see a salmon run, and the animals that depend on those large fish for food, on our computer screen.  Readers can do the same with the many live cameras that are broadcast.  
        





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