Looking At Various Weir Projects And Chinook Numbers

The salmon have started showing up at the various weir projects, some of which weren’t operable on time due to high water – but several have good reliable counts.  Unfortunately the weirs are verifying what the Bethel Test Fish showed – not only a late run but a weak one too for kings.

You can see for yourself.

Still tracking even below the worst years on record.

Here's a partial table showing the past few days of the BTF king cumulative CPUE

And now several weir projects validating the weak run as indexed by the Bethel Test Fishery:

George River Weir King Counts

Kogrukluk River Weir About 130 Miles Upriver Of Sleetmute On The Holitna

Tatlawiksuk River Weir King Counts

Tuluksak River Weir King Counts

The Tuluksak River Weir And Crew Of A Few Years Back

This type of weir is called a floating weir because the downstream end floats on the surface held up by styrofoam floats – the other end is anchored to the stream bottom.  Fish are passed through the counting chute where Age-Sex-Length data are collected.

Samples of fish are regularly observed where the proportion of females to males is quantified, the length of the fish are measured, and scales are collected to determine the age of the fish.  These are the data used to assess the characteristics of each year’s returns that can be compared to previous years.

One of the more important parameters of any run is the sex composition, because you may get a relatively large amount of fish back to a river but if the vast majority are males – that doesn’t bode well for future returns.

Weirs are the only way to get that type of information.

 

 

 

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