Sunday, August 12, 2012

It's Salmon Time!

The salmon are starting to spawn in earnest. Salmon spawn throughout the year, although most species' runs are concentrated between August and December. Different species spawn in different habitats and up different watersheds, at different times of year, so for wildlife that feed on salmon, the entire fall is a veritable smorgasbord of delicious food! Check out this great article published online by the University of Washington about diversity in the way salmon spawn.

There are five different species of salmon that spawn in the eastern Pacific up freshwater rivers and streams along the west coast of the United States: Chum, Coho, Chinook (also known as King salmon), Pink, and Sockeye. 

Yesterday, Jenn, Rigby, Quark and I started scouting areas to set up some of our trail cameras. We wanted to check some Pink and Sockeye spawning areas to make sure there is good fish activity this time of year. Check out this video I took of some Pink salmon spawning in a small creek just off the Chilkat River:

video

Male and female Pink salmon, as with many species, are sexually dimorphic when they breed. Sexual dimorphism is a term that refers to the fact that males and females have different physical appearances-- Male pink salmon are larger, and grow a hump and hooked jaw, while females remain smaller and streamlined. Pink salmon are also called "Humpies," and I'm sure you can tell why by watching the male Pink salmon in the video above!

There is plenty of evidence of bear activity in these areas. When salmon are high in abundance and bear densities are low, like the Pink salmon at this creek not far outside of Haines, bears high-grade salmon, eating only the most fat-rich parts of the salmon, including the roe (eggs), brains, and sometimes the skin, which often has a fatty layer underneath. Bears then leave the remnants of the salmon carcasses on the stream bank, where they're later accessed by scavengers, or sometimes washed back into the stream.

WARNING! If you don't want to see pictures of dead salmon, don't look below! (But I promise they're not super graphic... this time!)






This is a picture of two Pink salmon, one male and one female, that a bear left on the creek bank. Note that the bear was high-grading these fish: the female, on the left, had only the roe removed; the male, on the right, was missing its brain. Otherwise the carcasses were intact! It may seem wasteful to us, but bears have only a few short months this time of year to put on hundreds of pounds of weight to survive their hibernation during winter. The best way to put on weight is to eat only the fattiest, richest, and most caloric foods. No sense in filling up on muscle-- brains and eggs are the way to go.

We scouted some additional areas yesterday for Sockeye salmon, one which we'll revisit next week to install trail cameras. Before too long, we'll be able to share photos of scavengers that help clean up these leftover carcasses. Until then, you'll have to be content with this scenic picture of Nataga Creek, near its confluence with the Kelsall River.




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2 Comments:

At August 24, 2012 at 5:29 AM , Blogger Eric Moody said...

I get an address error when attempting to view the video. Specifically: "Cannot Open Page - Safari cannot open the page because the address is invalid".

Love your photos

 
At August 24, 2012 at 5:11 PM , Blogger Rachel said...

Hi Eric-

A few people have told me they've been having trouble viewing YouTube videos using Safari lately, so maybe that's the problem? If you're still having trouble, you can try viewing the video directly from our YouTube account: Pink Salmon Spawning. The quality there is a little bit better, too!

 

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