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[chris gadsden]

Filmed this today, the anglers were not part of the study as they were fishing the area before the crew started their
beach seining. They had just landed a fish, some will recognize the angler.

https://youtu.be/0qgPYXI2AXY

[Dave]

Wow, times have changed since buck, KP, bkk and I did this stuff!  Gillnets used for a mark recapture program ... wow!

I assume the fish were tagged later??

[wildmanyeah]

Filmed this today, the anglers were not part of the study as they were fishing the area before the crew started their
beach seining. They had just landed a fish, some will recognize the angler.

https://youtu.be/0qgPYXI2AXY

This looks like an awfully hard way to round up some chum.

[chris gadsden]

Wow, times have changed since buck, KP, bkk and I did this stuff!  Gillnets used for a mark recapture program ... wow!

I assume the fish were tagged later??

I did not stay to see if they did but I imagine that is what they were doing. Should they be using gloves?

[wildmanyeah]

I did not stay to see if they did but I imagine that is what they were doing. Should they be using gloves?

If they didn't have the budget to buy a seign I doubt they have one to buy gloves  lol

[Dave]

I did not stay to see if they did but I imagine that is what they were doing. Should they be using gloves?

This Chilliwack River chum enumeration study is so different from what we did a few years ago … and I hesitate to say more.

 The science of mark recapture is well known; tag them in the lower river when they are entering the system and recover carcasses later, throughout the system , getting a ratio of tagged to untagged fish.  From that a rough population is estimated.
When we did it we used seine nets to minimize mortalities; yes, wet wool gloves were used but the fish were within a few weeks of death anyway, so wet wool gloves were used to ensure less handling stress.
I understand, anecdotally, some fish this year have been captured and tagged in spawning areas.  That would not have happened a few years ago but I have been out of the game for 8 years. Perhaps there has been some new research I am not aware of to make this enumeration study more palatable to a few of us oldtimers
   

[wildmanyeah]

This Chilliwack River chum enumeration study is so different from what we did a few years ago … and I hesitate to say more.

 The science of mark recapture is well known; tag them in the lower river when they are entering the system and recover carcasses later, throughout the system , getting a ratio of tagged to untagged fish.  From that a rough population is estimated.
When we did it we used seine nets to minimize mortalities; yes, wet wool gloves were used but the fish were within a few weeks of death anyway, so wet wool gloves were used to ensure less handling stress.
I understand, anecdotally, some fish this year have been captured and tagged in spawning areas.  That would not have happened a few years ago but I have been out of the game for 8 years. Perhaps there has been some new research I am not aware of to make this enumeration study more palatable to a few of us oldtimers
 

Fish stress is a huge part of when they decide to spawn.  Handling them poorly could cause them to spawn in the next available ditch upstream and so what would be the point of tagging them. The Fraser River salmon Fishery is just a joke these days. Government hasn't cared about it for decades.  If it wasn't for volunteers nothing would get done. Yet the old timers remenus of the days where water bombers fertilized harrison lake and expo like hatchery funding.  lol oh god i'm ranting again

[TheLostSockeye]

This Chilliwack River chum enumeration study is so different from what we did a few years ago … and I hesitate to say more.

 The science of mark recapture is well known; tag them in the lower river when they are entering the system and recover carcasses later, throughout the system , getting a ratio of tagged to untagged fish.  From that a rough population is estimated.
When we did it we used seine nets to minimize mortalities; yes, wet wool gloves were used but the fish were within a few weeks of death anyway, so wet wool gloves were used to ensure less handling stress.
I understand, anecdotally, some fish this year have been captured and tagged in spawning areas.  That would not have happened a few years ago but I have been out of the game for 8 years. Perhaps there has been some new research I am not aware of to make this enumeration study more palatable to a few of us oldtimers
 

I have seen the same thing. Every time i have seen the researchers out they have been netting on the chum spawning beds. I have noticed dead chums with a green tag on the top fin on the back. I have seen them 3 times at tesky rock once at hopedale. seen lots of tagged chums at lickman so I assume they hit there to.
At tesky I observed there technique of laying the gill net across the channel and then proceeding to chuck large rocks all around the channel to spook some up into the net. It worked quite well.

[FishnForFun]

would hate for that rod guy to throw a rock at me.  a one shot quick and easy.

[buck]

Total waste of time and money. I would like to see the bs population estimate from this study.

[Dave]

Total waste of time and money. I would like to see the bs population estimate from this study.

   Tell us how you really feel, lol!

[RalphH]

Wow, times have changed since buck, KP, bkk and I did this stuff!  Gillnets used for a mark recapture program ... wow!

I assume the fish were tagged later??

I recall seeing lots of marked capture using gillnets on the Fraser back in the 60s and 70s. Whenever I later saw one of those fish I was surprised they would survive with that pin through the back below the dorsal fin. Am I correct that the tags used are much smaller than back then?

All that kind of work is contracted out now is it?

[Dave]

Never seen or been involved in any mark recapture programs using gillnets, until now

The work on the Chilliwack may well be contracted out but I'm pretty sure it's headed by DFO.  The tags you are referring to are Peterson disc; the pins are nickle silver and yeah, it is a brutal method of marking fish. In warmer systems bacterial infections would often occur but because the fish were most often dead within 10-14 days didn't really hamper the results. The whole idea is to recover the tags ...
I don't know what tags are being used on the Chilliwack this year; perhaps others could chime in.
 

[chris gadsden]

i was fishing with the Master today and we did not see them. Will try to find them for some closer video with my trusty camera and get more information, if they are allowed to talk.

[dnibbles]

Never seen or been involved in any mark recapture programs using gillnets, until now

This is a DFO project, but it is funded through the Pacific Salmon Commission (i.e. funding from the US, maybe wasting Trump's dollars anger buck as well?). It's the first year they've done it here. There are several other places in BC where tanglenets are used to conduct mark-recapture programs, including the Atnarko River near Bella Coola. A small mesh size needs to be used to avoid gilling the target species if possible. Seine nets can have lots of mortality issues as well if not used in the correct conditions/fashion. That's why different methods (tangle net, seine, angling, fish fence) are used at different times, different tools for different jobs. ON the Quinsam River they actually just tag carcasses instead of live fish, and then re-survey the dead to estimate the population.

I have also seen high densities of tagged carcasses in some areas on the Vedder (it looked like close to 80% of the carcs were tagged when we were walking in to beak out KP's dugout last month). I didn't look closely, but they looked like standard petersen disc tags, along with opercular punches for secondary marks. If they are targetting spawners (which I would assume if they are tagging the side channel areas) then the tags themselves are unlikely to be the main stressor for these fish, as they will likely be dead long before the tags could cause infection-related mortality.  The study design needs to match the analytical design, not all mark-recaptures are like the one you describe Dave, with tagging at the bottom and full dispersal throughout. I play hockey with the head biologist on this project, so I'll ask him about his bs program tomorrow and get some info for you grumpy old men. I will also let him know he can save $50K and just get the exact escapement estimate from this thread.

I am glad to see some effort being directed at monitoring Fraser River chum this year, they've been ignored for a long time so happy to see DFO putting resources into it. I'm sure they will learn this year and improve things for next.

Dave (an equally grumpy but slightly less old man)