# Salmon and wolves



## Jennifer Coulter (Sep 18, 2007)

I think I posted these cool pics of costal wolves eating/fishing salmon once in the past.

http://s161.photobucket.com/albums/t214/farwesttoller/?action=view&current=NewPicture.jpg
http://s161.photobucket.com/albums/t214/farwesttoller/?action=view&current=NewPicture3.jpg
http://s161.photobucket.com/albums/t214/farwesttoller/?action=view&current=NewPicture1.jpg
http://s161.photobucket.com/albums/t214/farwesttoller/?action=view&current=NewPicture5.jpg


Due to the fact that coastal salmon are known to carry parasites that are dangerous to dogs, I wondered how wolves got away with eating them.

I just watched some show called "Rainwolves" about wolves living in costal British Columbia, Canada. Apparently these wolves only eat the heads of the fish. They showed close to one hundred salmon with only the heads eaten by wolves. Other animals and birds clean up the rest. Bears are able to eat the whole fish for example.

Somehow they know what part of the fish they can eat and what part is dangerous to them. How they make that connection and how long that took...I am not sure. Facinating.

I appolagize it this was common knowledge. Just thought it was neat.


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## Lindsay Janes (Aug 9, 2007)

That's interesting. Maybe Jennifer Marshall will know about this one.


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## Lynn Cheffins (Jul 11, 2006)

"Rainwolves" is a really interesting documentary - very worthwhile watch.
I think one of the reasons they only eat the heads is that the spawning salmons bodies are pretty depleted of fat and the the head is the one part of the fish that has a fat reserve left so is therefore more beneficical to the wolves to eat heartily of the most nutritious part of the fish when there is fish in abundance.


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## Howard Knauf (May 10, 2008)

He's a better fisherman than me. Thats a nice sized fish. Ya think they learned how to do it by watching the bears?:-k


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## leslie cassian (Jun 3, 2007)

Jennifer, you rock! Cool photos.

I tried feeding fresh fish heads (from the supermarket) to my dogs. It was not a well received treat. Ended up cooking them into soup. I guess my dogs are pretty far from their wolf ancestors.


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## Bob Scott (Mar 30, 2006)

I don't know if wolves follow the same pattern as bears but it could depend on the season. 
The bears eat every part of the fish early in the spawning season. As they become satisfied they eat more of just the eggs and skin (contains fat). 
Same with a Polar bear. It eats only the seal fat if it's having a good year.


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## Jason Sidener (Nov 8, 2006)

Very cool pics !!!


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## Jennifer Marshall (Dec 13, 2007)

Lindsay Janes said:


> That's interesting. Maybe Jennifer Marshall will know about this one.


 
I've been around dogs that catch fish, it is really quite amazing to see. I have not seen Rain Wolves so I don't know exactly what was said in the show.

My guess would be that the wolves are just not affected by Neorickettsia helminthoeca the way/to the extent that dogs are. I've heard for a while that all canids (wolves, foxes, coyotes etc) would be affected by it the same as dogs. But then I've also read that they aren't necessarily and don't know what to think. I've read that the flukes containing N. helminthoeca are parimarily in the organs (liver and kidneys) but I've read that it can be in the flesh of the body and the in the brain as well. 

Sooooo I'm confused on the matter but my guess would be that wolves are likely not as affected by salmon poisoning the way that dogs are. I do think they are susceptable but not as sensitive.

This is all 100% opinion. I don't suggest raw salmon(pacific salmonids in general) be fed to dogs.

I think of everything I've read I agree with this the most: 

"
Consumption by wolves of salmon heads was disproportionate
to other body parts, and this pattern appears widespread.
Wolves used only the head portion of all salmon captured and
consumed (​​_n _= 64). Similarly, Young and Goldman (1944)
quoted a biologist in Alaska who observed wolves that “had
taken salmon…eating only their heads”. Headless salmon carcasses
found upstream at the Kunsoot River and elsewhere
where wolf sign was abundant but where we did not directly
observe foraging strongly suggested wolves were preying on
salmon. We note, however, that bears and other carnivores also
prey on salmon and may selectively consume the head (but see
following discussion regarding different tissue consumption by
bears).

Multiple processes may be involved in a preference for
head tissue. Consuming only energetically valuable portions
of a prey item may maximize net returns, particularly if prey
is abundant and easily captured (e.g., Sih 1980). Black bears
on Haida Gwaii, B.C., also preferentially take the lipid-rich​
brain of freshly captured salmon, but consume eggs, and
dorsal and lateral trunk musculature as well (Reimchen 2000).
In addition to calories, bears and wolves may also be targeting
specific nutrients in salmon heads (Gende et al. 2001).
Docosahexaenoic acid, an omega-3 fatty acid, is essential
for nervous system function, can be obtained only from diet,
and occurs in high proportion in brain and optic tissue (Horrocks
and Yeo 1999; Connor et al. 2001). In addition, animals often
make foraging decisions to minimize exposure to parasites
(Lozano 1991; Hart 1994). Salmon can be infected by​_Neorickettsia helminthoeca​_​​via a trematode vector (_Nanophyetus
salmincola_). _Neorickettsia helminthoeca _causes “salmon
poisoning disease”, which can be fatal to canids (Young and
Goldman 1944; reviews in Philip 1955; Knapp and Millemann
1970). Metacercariae of _N. helminthoeca _occur in the head and
dermal tissue of salmon but are thought to concentrate in kidney
and muscles of infected fish (Bennington and Pratt 1960;​
Baldwin et al. 1967)."

From: http://web.uvic.ca/~reimlab/wolfsalm.pdf
 
Maren, what say you?


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## Jennifer Coulter (Sep 18, 2007)

leslie cassian said:


> Jennifer, you rock! Cool photos.
> 
> I tried feeding fresh fish heads (from the supermarket) to my dogs. It was not a well received treat. Ended up cooking them into soup. I guess my dogs are pretty far from their wolf ancestors.


I did not take those photos. I did not mean to pass them off as my own. They were e-mailed to me by someone else, I don't have any original photographer to credit. They are great though.

My current dog will eat fish heads. My last one just would have rolled on them#-o


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## Jennifer Coulter (Sep 18, 2007)

I hope I see that show again sometime. I was only half paying attention until the fish part came up. It was mentioned that the heads are high in EFA's and I thought something possibly about parasites, but I am not sure I caught the whole thing. 

Even cooler (I think, but I am a nature geek) is the relationship of the spawning salmon to the growth of the forest caused by all the fish carcasses brought into the woods (mostly by bears I beleive, but wolves and birds to a smaller extent) and the nitrogen released in the decay fertilizes the plants of the forest.

Thanks for that extra info Jen M. Pretty cool stuff. It sounds as though it may be from the same researchers that did the documentary, I thought I remembered them being from U Vic, but not entirely sure. I have personally seen bears eat more than heads. Obviously wolves and bears differ greatly in their diet and a whole lot more !


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## Lindsay Janes (Aug 9, 2007)

Jennifer Marshall said:


> Maren, what say you?[/SIZE]


 It would be interesting to see what Maren has to say about this one since she's studying to be a veterinarian too.


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