FISH IS THEIR ECONOMY

      I've never visited Alaska until the summer and autumn of 2020, by live camera at a couple of small sites on Brook's River in Katmai National Park, at the base of the Aluetian Islands, and on our computer screen.  The cameras are focused mostly on brown bears fattening on live sockeye salmon going upstream to spawn in summer and dead salmon in fall until at least the end of October, before winter sets in.  But the cameras reveal that other kinds of wildlife also benefit from dead salmon in the river in fall.  The economy of all that wildlife is based on fish.

     By late October, this part of Alaska looks like winter.  Daylight each succeeding day is noticeably shorter.  Tall grasses along river shores are yellow and spruces back from the shore a little stand out against bare deciduous forests in the background.    

     In autumn, many brown bears and brown bear families converge on Brook's River to feed on dead salmon, the most abundant food for them in that area.  Some bears push through shallow water with their eyes underwater to watch for salmon carcasses.  Other bears submerge completely in the water to examine the bottom for bodies.  And all those bears bring the carcasses to the surface to feed on, sometimes leaving some of the dead fish uneaten.

     Flocks of glaucous-winged gulls, both the young of the year and adults, swarm around the bears in the water and wait for tidbits of torn-apart salmon to float on the water, which they seize in their bills to eat.  All gulls are devout scavengers and these big ones are no exception.  But glaucous-wings also catch small fish and other creatures from rivers and coastal waters by tipping forward and reaching their beaks as deep into the water as they can.

     Interestingly, twice, but in different days, I saw a brown bear charge a group of swimming glaucous-winged gulls and catch a gull, drag it out of the water and consume it.  One never knows what he or she will see in the wild.            

     Little swarms of pretty Bonaparte's gulls, which are small and dainty, arrived at Brook's River in late summer, after they raised young around forest-rimmed lakes in Alaska and Canada.  Bonnies repeatedly flutter up six feet from the water, poise momentarily, then drop, beak-first, into the water after small fish or other prey, and tidbits of salmon in the water that were left by the bears.   

     Armadas of common merganser ducks also congregate around the bears on Brook's River where they catch small fish, and scavenge bits of salmon from the bears' meals.  These long-bodied ducks dive under water from the surface to get food. 

     Early in October, flocks of attractive Barrrow's goldeneye ducks suddenly flooded parts of Brook's River.  And during October they continually dove under water from the surface to consume aquatic invertebrates, and bits of salmon left by the sloppy bears.  

     Flocks of mallard ducks also hung around the bears, probably to eat salmon scraps.  Mallards are very adaptable and will eat most anything, anywhere, anytime.  

     A few majestic bald eagles were also along the parts of Brook's River broadcasted by the live cameras.  Bald eagles are capable of catching live fish and other wildlife, but they definitely are not above scavenging dead creatures of several kinds.  By live camera, I could see them pulling salmon carcasses out of the river and flying to a tree or log fallen into the river to ingest their prize.       

     Small groups of common ravens and individual black-billed magpies ingest dead salmon that were left by the bears on shores and little islands in the river.  These crow relatives, like the gulls, ducks and eagles, put on weight by eating lots of the omni-present salmon parts.  Gorging on salmon now will help see the brown bears and all these bird species through the soon-coming winter.  

     This is another example of wildlife depending on each other for life.  The abundant salmon spent from spawning and scavenging brown bears help feed a variety of adaptable, scavenging birds that take advantage of feeding situations, wherever and whenever they occur.       

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