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Thursday, August 25, 2011

Mergansers mark autumn

It's hard to say goodbye to a summer that was never really here. 
Summer must have passed while we were waiting for it to show up. 
There were the signs of autumn. 
There was fog on the salt chuck. 
The vine maple leaves started turning red.  
One day a flock of mergansers flew up river and I knew that we were in for it. 
There were 17 birds in the bunch, a mother and 16 babies. 
I'd seen these birds before. 
Mergansers are a big fish-eating diving duck about the size of a mallard. The males almost look like mallards with their iridescent green heads. Unlike a mallard the mergie has its webbed feet strategically located further astern to help it dive underwater. 
Instead of a duck bill, the merganser has a hooked beak full of tooth-like barbs that make it a fish eating machine. Mergansers spend their winters fishing on the salt water. 
With the coming of spring they fly upriver to mate and feed on the downstream migration of anadromous fish that are headed to the ocean. 
The colorful plumage of the male merganser is a stark contrast to the pale brown feathers of the females. There could be many reasons for this. Females are attracted to bright colors but they want to be camouflaged proper to nest.     
The mothers get killed defending their young from predators so it figures there are a fewer females than males. The excess male population needs some pretty nice feathers to compete in the brief mating game. 
When it is over, the males fly back out to sea, to the north in great flocks, to spend summers working on their feathers. The females are left on the river to raise a brood in a world where everything wants to eat them. 
She begins by laying her eggs in the hollow cavity of a cottonwood tree that might be a 100 feet or more above the ground. When the eggs hatch the ducklings have to get out of that tree or starve. They pile out of the nesting tree with only a cushion of salmonberry bushes to break their fall. 
Then they head to the river to get something to eat. Their mother keeps them in the shallows near shore eating bugs and the baby salmon that have just hatched out of the gravel. It is at this time that counting the number of chicks in a merganser brood can indicate the health of a river. In the upper Elwha where there are no salmon you just don't see many mergies. In the Hoh where there are salmon, I saw sixteen babies in one family. The most I've seen is 22! 
One or two will ride on their mothers' back while the rest paddle along to keep up. The mother has to feed each one individually which can make for a long chow line.  
While she is catching fish for her brood, the mother has to be on guard constantly against all the animals that want to eat them. Imagine having a picnic with the children where you have to catch the meal. While you are poking around for a fish, a crow is pecking at one of your babies. 
Overhead a pair of eagles, who have young to feed, are waiting to swoop down for an easy meal. On shore there are raccoons, snakes, mink and weasels all hunting baby ducks. 
So when you see a mother mergie flying upriver with the same number of chicks she started out with, you know she was a good mom and summer is over. 

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