Respected UBC Professor Carl Walters advocates for seal and sea lion cull

[cohochinook]

The story was on CBC news last night. Dr. Carl Walters from the UBC Fisheries program is advocating for a seal and sea lion cull. Good to see that a respected Professor is looking at the science and giving his opinion:

https://www.cbc.ca/news/thenational...ls-and-sea-lions-to-save-the-whales-1.4919368

 

[searun]

That is not exactly correct. Dr. Walters is suggesting an experiment. Not a cull. There is scientific evidence that in terms of pinniped predation, the number one culprit is in fact Harbour Seals. And, that most harbour seals are not habituated to preying upon salmon smolts - that is where the most numbers of individual salmon and steelhead are going. So, what is suggested is very selective predator control of only those animals at specific high predation locations be addressed in controlled experiments.

No one is supporting an all out "cull." That would be badly irresponsible, and not something the Public or Science would support. These groups that are out there promoting all out culls are not following the science, and are actually putting at risk any hope of initiating a responsible science-based selective control program.

Calls for culls have to STOP - they are going to damage any efforts towards responsible actions.

 

[fogged in]

[QUOTE="searun, post: 905826, member: 466"
Calls for culls have to STOP - they are going to damage any efforts towards responsible actions.[/QUOTE]
Gota disagree searun.
I would agree culling Sea Lions and Seals would not totally solve the problem of the declining salmon runs, but it would certainly help!
Just like removing Fish Farms would help!

 

[SerengetiGuide]

Wolf cull is working well for caribou.

 

[Peahead]

That is not exactly correct. Dr. Walters is suggesting an experiment. Not a cull. There is scientific evidence that in terms of pinniped predation, the number one culprit is in fact Harbour Seals. And, that most harbour seals are not habituated to preying upon salmon smolts - that is where the most numbers of individual salmon and steelhead are going. So, what is suggested is very selective predator control of only those animals at specific high predation locations be addressed in controlled experiments.

No one is supporting an all out "cull." That would be badly irresponsible, and not something the Public or Science would support. These groups that are out there promoting all out culls are not following the science, and are actually putting at risk any hope of initiating a responsible science-based selective control program.

Calls for culls have to STOP - they are going to damage any efforts towards responsible actions.

Actually searun Carl Walters does say he believes that reducing seals would help SRKW. Thats his opinion, despite his suggesting an experiment to make sure his belief is correct or not.

"The thing that will really benefit the SRKW is to see improved survival rate of small Chinook and the only way [he believes] this can be achieved is by reducing seal numbers" I'd say that would pretty much mean he believes in reducing seals (advocating a seal cull). He mentions afterwards that an experiment would best be done first [to prove his and others belief is correct or not]

[QUOTE="searun, post: 905826, member: 466"
Calls for culls have to STOP - they are going to damage any efforts towards responsible actions.

Gota disagree searun.
I would agree culling Sea Lions and Seals would not totally solve the problem of the declining salmon runs, but it would certainly help!
Just like removing Fish Farms would help![/QUOTE]

Actually while I agree with a limited seal cull, it is not just like removing fish farms. Removing fish farms doesn't have the concern of a removal causing a negative effect to the balance of nature. For example with a seal cull one has to be careful as they are food for Biggs whales . A seal cull can also cause an increase of other predators on Chinook since seals do eat fish that consume young Chinook. I am learning more as to how complex the removal of seals is to the balance of nature. Removal of fish farms is quite a different thing so I personally would not use that analogy to back my support of a limited seal control (cull).

 

[terrin]

Actually searun Carl Walters does say he believes that reducing seals would help SRKW. Thats his opinion, despite his suggesting an experiment to make sure his belief is correct or not.

"The thing that will really benefit the SRKW is to see improved survival rate of small Chinook and the only way [he believes] this can be achieved is by reducing seal numbers" I'd say that would pretty much mean he believes in reducing seals (advocating a seal cull). He mentions afterwards that an experiment would best be done first [to prove his and others belief is correct or not]



Gota disagree searun.
I would agree culling Sea Lions and Seals would not totally solve the problem of the declining salmon runs, but it would certainly help!
Just like removing Fish Farms would help!

Actually while I agree with a limited seal cull, it is not just like removing fish farms. Removing fish farms doesn't have the concern of a removal causing a negative effect to the balance of nature. For example with a seal cull one has to be careful as they are food for Biggs whales . A seal cull can also cause an increase of other predators on Chinook since seals do eat fish that consume young Chinook. I am learning more as to how complex the removal of seals is to the balance of nature. Removal of fish farms is quite a different thing so I personally would not use that analogy to back my support of a limited seal control (cull).[/QUOTE]
Are you saying that removing Fish Farms would not be complex and would not upset the balance of nature and therefore be a good candidate for a cull?

 

[Peahead]

Actually while I agree with a limited seal cull, it is not just like removing fish farms. Removing fish farms doesn't have the concern of a removal causing a negative effect to the balance of nature. For example with a seal cull one has to be careful as they are food for Biggs whales . A seal cull can also cause an increase of other predators on Chinook since seals do eat fish that consume young Chinook. I am learning more as to how complex the removal of seals is to the balance of nature. Removal of fish farms is quite a different thing so I personally would not use that analogy to back my support of a limited seal control (cull).

Are you saying that removing Fish Farms would not be complex and would not upset the balance of nature and therefore be a good candidate for a cull?[/QUOTE]

I am saying in response to Fogged -in's suggestion that removal of farming is comparable to doing a seal cull, that the comment is not true because removal of fish farming does not have same NEGATIVE consequences with removal as a seal cull could have. I explained above as to why. HOWEVER I would agree removing fish farms ( or moving to land based as I would like to see) is still a complex step, especially for financial reasons.

 

[Deewar25]

Really think focus needs to be this 'selective cull' and not this 1/2 removal etc that has been circulating. This is the only way to meet in the middle with the groups that oppose such actions and I think there is more than enough evidence and argument to justify it. It is staggering to me to consider that seals alone are possibly taking 86% of all outgoing smolts every year - the numbers consumed is estimated at 27 million annually! That's 500 million lbs of potential adult fish. This must by our focus IMH. I read that a large % of damage is done by a small percent of seals with this destructive learned behaviour - remove these - not the ones out in the ocean providing transient food, comsuming hake, and doing their thing. You will hear over and over that culls don't work, and that has to be considered as well - they recently did this in Washington and just found while Cali sea lions were effectively removed, they were replaced by more damaging stellar sea lions. That is bad news and likely more a US problem, but has to be factored in. I do however see the merit with the Puntledge cull and that is a case of huge success with minimal seal population impact. To quote the analysis of that case study : "However, in 2001-02 chinook returns to the Puntledge River increased substantially more than returns to neighboring rivers. The removal of habituated in-river seals and the corresponding reduction in both juvenile and adult salmon predation could have been one of many possible factors contributing to the increase in chinook returns."

We are talking from under 1000 returns to well over 10000 and since sustained with several 1000 annually with removal of only 50 seals. That is success in my books and should be our focus. Remove 50-100 seals over a dozen rivers may be truly all we need to do.

The right message to the public is what is needed and a few initiatives I feel are putting out the wrong one right now - we need to dial that in.

 

[Peahead]

Really think focus needs to be this 'selective cull' and not this 1/2 removal etc that has been circulating. This is the only way to meet in the middle with the groups that oppose such actions and I think there is more than enough evidence and argument to justify it. It is staggering to me to consider that seals alone are possibly taking 86% of all outgoing smolts every year - the numbers consumed is estimated at 27 million annually! That's 500 million lbs of potential adult fish. This must by our focus IMH. I read that a large % of damage is done by a small percent of seals with this destructive learned behaviour - remove these - not the ones out in the ocean providing transient food, comsuming hake, and doing their thing. You will hear over and over that culls don't work, and that has to be considered as well - they recently did this in Washington and just found while Cali sea lions were effectively removed, they were replaced by more damaging stellar sea lions. That is bad news and likely more a US problem, but has to be factored in. I do however see the merit with the Puntledge cull and that is a case of huge success with minimal seal population impact. To quote the analysis of that case study : "However, in 2001-02 chinook returns to the Puntledge River increased substantially more than returns to neighboring rivers. The removal of habituated in-river seals and the corresponding reduction in both juvenile and adult salmon predation could have been one of many possible factors contributing to the increase in chinook returns."

We are talking from under 1000 returns to well over 10000 and since sustained with several 1000 annually with removal of only 50 seals. That is success in my books and should be our focus. Remove 50-100 seals over a dozen rivers may be truly all we need to do.

The right message to the public is what is needed and a few initiatives I feel are putting out the wrong one right now - we need to dial that in.

Thumbs up to your post above! Pretty much how I feel as well. I suspect Dr Walters suggested an experiment be done first (even though he states he believes a cull is necessary) to remove any doubt people may have to the success of doing a control on seals. He has already said he believes it will help.

 

[wildmanyeah]

Really think focus needs to be this 'selective cull' and not this 1/2 removal etc that has been circulating. This is the only way to meet in the middle with the groups that oppose such actions and I think there is more than enough evidence and argument to justify it. It is staggering to me to consider that seals alone are possibly taking 86% of all outgoing smolts every year - the numbers consumed is estimated at 27 million annually! That's 500 million lbs of potential adult fish. This must by our focus IMH. I read that a large % of damage is done by a small percent of seals with this destructive learned behaviour - remove these - not the ones out in the ocean providing transient food, comsuming hake, and doing their thing. You will hear over and over that culls don't work, and that has to be considered as well - they recently did this in Washington and just found while Cali sea lions were effectively removed, they were replaced by more damaging stellar sea lions. That is bad news and likely more a US problem, but has to be factored in. I do however see the merit with the Puntledge cull and that is a case of huge success with minimal seal population impact. To quote the analysis of that case study : "However, in 2001-02 chinook returns to the Puntledge River increased substantially more than returns to neighboring rivers. The removal of habituated in-river seals and the corresponding reduction in both juvenile and adult salmon predation could have been one of many possible factors contributing to the increase in chinook returns."

We are talking from under 1000 returns to well over 10000 and since sustained with several 1000 annually with removal of only 50 seals. That is success in my books and should be our focus. Remove 50-100 seals over a dozen rivers may be truly all we need to do.

The right message to the public is what is needed and a few initiatives I feel are putting out the wrong one right now - we need to dial that in.

Bingo all it took was 1 seal at the little Campbell river fish fence too kill a bunch of retiring salmon a few years ago, tails and heads scattered up and down the bank. Herd about it
First hand from some people at my SFAC devastating to the system.

https://vancouversun.com/news/local...ductive-little-campbell-river-in-south-surrey

“Two weeks ago — and for the first time to anyone’s knowledge — a couple of harbour seals made their way upriver to the hatchery’s steel fish-counting fence, nine kilometres from the ocean, in hopes of a cheap meal.

 

[OldBlackDog]

FYI, just a few facts for you, taken from the site.


Monday I am taking a break from promoting Pacific Balance Pinniped Society throughout Facebook. Too much negativity of late and I feel like I went 18 rounds with General Bubba Custer with one arm tied behind my back. Time to take a breather and focus on positive ambitions for a day.

I ask you to learn that SHARE to a group button/clicks. Be nice to see y'all share it to other groups you are members of?

I leave y'all this post with data that our founding director Ken Pearce forwarded me. It will astound you, anger you and hopefully put wind in your sails to share and get word out about our society's initiative? He's our data man and I asked him to compile references to scientific and other reports about the data on pinniped numbers. I was gobsmacked to say the least when I reviewed his summary!

March 31, 2018 SOME UPDATES AS OF NOVEMBER,2018

THINKING OUTSIDE THE BOX

For as long as I can remember, the focus on our dwindling stocks of Pacific Salmon, particularly Chinook and Coho has been around the usual culprits.

Logging, urbanization of streams, pollution of the various waterways, both fresh(spawning streams and rivers) and salt, over fishing, lack of proper management of the various user groups taking advantage of over harvesting due to lack of surveillance ( I e. over limits by sporties, poaching by various groups at the mouths of spawning streams and in the rivers and streams, poor management of actual “real numbers” of over fishing quotas, and lack of current accurate numbers of spawners returning to all of our spawning systems, and the list goes on.

My thoughts were aroused after thoroughly reading the following papers.

1. The current Salish Sea Marine Survival Project on Predation by Ben Nelson, et all.
2. Seals and sea lions may be slowing salmon recovery, hurting Orcas. By
Chistopher Dunagan.
3. Several papers posted in the Columbia Basin Report.
4. An extensive paper presented by the Gill Netters Association in the late
1900's
5. Brandon E.Chasco et all NOAA
6. Dr.Walters et all Oceans and Fisheries at UBC
7. Pacific Salmon Foundation Salish Sea Marine Survival Projects
8. Peter Olesiuk Oceans and Fisheries at UBC

Several very significant scientifically proven facts stand out and run a common thread through the above papers.

1.Harbor seals, protected by the Marine Mammal Protection Act of 1972 have nearly doubled in numbers in the inland waterways since 1972—going from 210,000 to 355,000

On the North East Pacific they grew from 350,000 to 1,126,469
2.California sea lions grew from 5,900 to 47,000 3. Stellar sea lions increased from 74,400 to 78,500 4 Transient Orcas grew from 294 to 644 5 In the Salish Sea the Harbour Seal population grew from 8,600 in 1975 to 80,000

I'll summarize the numbers from the Gill Netter Association. These numbers come from D.F.O. publications, of which I have the copies.

HARBOR SEALS POPULATIONS
1. North coast Pacific: 1987 – 350,000 1997 1,126,469
2. B.C. Coast: 1987 1997 209210 current numbers are stated at 355,000.
3. Georgia Straight: 1987 12,500 1997 40,250 current numbers are 45,000

FUR SEAL POPULATIONS
1. North East Pacific 1987 900,000 1997 2,898,000

CALIFORNIA SEA LIONS
1. North East Pacific 1984 120,000 1997 333,600
2. B.C. Coast 1984 4500 2015 47,000

STELLAR SEA LIONS:
1.North East Pacific 1984 200,000 1997 556,000
2. B.C. Coast 1984 13,000 2015 78,500

FOOD CONSUMPTION OF THE ABOVE GROUPS.

I have not found any written evidence of the break down of their food groups?

I am using the consumption numbers published in the above papers. For Harbour seals,they range from 5lbs/day to 14/lbs/day

The consumption numbers for California sea lions range from 30lbs/day to 50lbs/day.

The numbers for Stellar sea lions ranged from 40 to 60lbs/day

The numbers for Fur seals was stated at 5.5lbs/day

For simplification of the math I used the following rounded consumption numbers
1. Harbour Seals 10 lbs/day

2.California Sea Lions 40lbs/day

3.Stellar Sea Lions 50lbs/day

4.Fur Seals 5lbs./day

The consumption math falls into place as follows for the current time period

Species Herd size Pounds/day total lbs./day

Harbour seals 1,126,469 10 11,264,690

California lions 339,600 40 13,584,000

Stellar lions 356,000 50 17,800,000

Fur Seals 2,898,000 5.5 15,939,000

That does not include the consumption by Orcas (664 outside 70 inside)

Grand totals: 58,587,690lbs/day!!

Totals per month (assume 30 day month) 1,757,631,000 lbs/mo

That is 878,810 tons/mo.

1 current seine boat can hold 55 tons which equals 15,978/boat loads/mo!!

For sake of argument lets assume that that consumption rate is 50% of various salmons ( Chinook, coho, sockeye, pinks, chums, steel head) which is most likely a low number.

The numbers for salmon consumption ( remember no Orcas included here)
would be: 439,405 tons/mo

Again for easy math, lets assume the average weight of
salmon to be 10 lbs. There for consumption of salmon in this
analysis would be: 4,394,050 salmon/mo!!

WONDER WHERE OUR SALMON ARE DISAPPEARING TO???

The growth rate of the seals and sea lions et all averages 10% plus ( compounded)/year and the production of salmon is not even close to keeping up to this number.

Now we add in the destruction ( consumption) caused by seal predation on smolts in the estuaries to this mix.

Dunagan states the production of Chinook smolts alone in the West Coast area, including hatcheries and wild is 29,000,000.

He also states that the consumption of Chinook smolts to be 85% or 24,000,000.

Similar current studies ( as stated above) on the Big Qualicum, Cowichan and Puntledge show that the seal predation to be 1 kg/seal/day of coho smolts. At 2g/smolt that is 100 coho smolts/day x how many seals ?

The above study ( of which the P.S.F. was also involved) did not include Chinook.

These are staggering numbers and need to be addressed as soon as possible.

Is it a wonder that our resident Orcas are short on their favorite meal of chinooks???

Your thoughts, please

Ken Pearce
605 839 7756
kpearce1@telus.ne

 

[Deewar25]

FYI, just a few facts for you, taken from the site.

That is wrong message - people throw around the ridiculous numbers about amount of fish seals/sea lions consume like they are only consuming chinook every day of the year. You want to be taken seriously, don't post outlandish information like that (not blaming you of course for posting, but those that keep stating those kinds of numbers). That will be squashed every time. Use the information they accept as gospel but also focus on key areas. Plenty of evidence that diets consist of many types of fish 12 months of the year. US studies are clear thou that only the spring smolt and returning spawners are the concern as chinook consumption goes. It appears sea lions are feasting for sure in US rivers and chinook may be large % of daily intake for a few weeks a year, and the seals are obviously chowing down on smolts here. NGO's are generally accepting this fact, but tend not to point it out much. Of course 20 billion lbs of chinook are not being consumed annually though so I just don't think we should be going there. I mean using 500 million/year (equiv adults from smolt consumption) is enough of a dent when you consider the entire BC take commercially/recreationally is about 8 million.

Keeping it real is really important.

 

[OldBlackDog]

Interesting, exactly what numbers do you not agree with?
Further, please provide your facts/reports that show this to be wrong.

That is wrong message - people throw around the ridiculous numbers about amount of fish seals/sea lions consume like they are only consuming chinook every day of the year. You want to be taken seriously, don't post outlandish information like that (not blaming you of course for posting, but those that keep stating those kinds of numbers). That will be squashed every time. Use the information they accept as gospel but also focus on key areas. Plenty of evidence that diets consist of many types of fish 12 months of the year. US studies are clear thou that only the spring smolt and returning spawners are the concern as chinook consumption goes. It appears sea lions are feasting for sure in US rivers and chinook may be large % of daily intake for a few weeks a year, and the seals are obviously chowing down on smolts here. NGO's are generally accepting this fact, but tend not to point it out much. Of course 20 billion lbs of chinook are not being consumed annually though so I just don't think we should be going there. I mean using 500 million/year (equiv adults from smolt consumption) is enough of a dent when you consider the entire BC take commercially/recreationally is about 8 million.

Keeping it real is really important.

 

[searun]

Interesting, exactly what numbers do you not agree with?
Further, please provide your facts/reports that show this to be wrong.

Those numbers are spin doctoring. Wild and far out assumptions are being used and is in no way science-based. For starters they are based on 365 days...when was the last time we saw full abundance of salmon 365 days a year? If you tell me there is, I have a bridge in swamp land for sale.

 

[OldBlackDog]

Please show us exactly what numbers and papers used are wild and far out.
Please as the author did provide your background for your opinions.

Those numbers are spin doctoring. Wild and far out assumptions are being used and is in no way science-based. For starters they are based on 365 days...when was the last time we saw full abundance of salmon 365 days a year? If you tell me there is, I have a bridge in swamp land for sale.

 

[wildmanyeah]

They are a bit ridiculous because they refer to the total biomass consumed by seals. It indeed is a very large amount but mostly bait fish.

If we are concerned about baitfish then humpback whales eat a **** tonne.

 

[OldBlackDog]

CTV news tonight, Puntledge River.

 

[Deewar25]

Interesting, exactly what numbers do you not agree with?
Further, please provide your facts/reports that show this to be wrong.

I don't agree with the overall daily consumption of salmon - note he says 'food consumption' but then turns the same numbers into salmon consumption. Big difference as for much of the year, most of their diet is herring, hake, cod, dogfish, sandlance, as well as salmon. Infact scat studies from US show in winter/spring, only 5-10% of diet is made up of salmon (all species). As that was San Juan based (not rivers) it wouldn't be factoring in smolt during spring time. Summer and fall consumption is much higher, but they can't tell the species of salmon, only the overall amount (found in 50% of samples).
You can find that study and charts here as an example: https://www.researchgate.net/public...ons_for_the_recovery_of_depressed_fish_stocks

As I said, focus on key areas locally - spring time smolt consumption, and fall returns to the river/easy pickings. Enough damage in that alone & a more sound argument IMH. That's all I'm saying.

 

[OldBlackDog]

And what number do you have that shows this?
As noted could not find a breakdown on fish eaten.

Also what number of the salmons diet are they eating and what effect is that having?

They are a bit ridiculous because they refer to the total biomass consumed by seals. It indeed is a very large amount but mostly bait fish.

If we are concerned about baitfish then humpback whales eat a **** tonne.

 

[trophywife]

Actually searun Carl Walters does say he believes that reducing seals would help SRKW. Thats his opinion, despite his suggesting an experiment to make sure his belief is correct or not.

"The thing that will really benefit the SRKW is to see improved survival rate of small Chinook and the only way [he believes] this can be achieved is by reducing seal numbers" I'd say that would pretty much mean he believes in reducing seals (advocating a seal cull). He mentions afterwards that an experiment would best be done first [to prove his and others belief is correct or not]



Gota disagree searun.
I would agree culling Sea Lions and Seals would not totally solve the problem of the declining salmon runs, but it would certainly help!
Just like removing Fish Farms would help!

Actually while I agree with a limited seal cull, it is not just like removing fish farms. Removing fish farms doesn't have the concern of a removal causing a negative effect to the balance of nature. For example with a seal cull one has to be careful as they are food for Biggs whales . A seal cull can also cause an increase of other predators on Chinook since seals do eat fish that consume young Chinook. I am learning more as to how complex the removal of seals is to the balance of nature. Removal of fish farms is quite a different thing so I personally would not use that analogy to back my support of a limited seal control (cull).[/QUOTE]


Biggs whales are starting to push out SKRW as their numbers are flourishing and areas of predation is expanding.