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Archive for August, 2011

From Science Daily:

As wolf populations grow in parts of the West, most of the focus has been on their value in aiding broader ecosystem recovery — but a new study from Oregon State University also points out that they could play an important role in helping to save other threatened species.

In research published in Wildlife Society Bulletin, scientists suggest that a key factor in the Canada lynx being listed as threatened under the Endangered Species Act is the major decline of snowshoe hares. The loss of hares, the primary food of the lynx, in turn may be caused by coyote populations that have surged in the absence of wolves. Scientists call this a “trophic cascade” of impacts.

The increase in these secondary “mesopredators” has caused significant ecosystem disruption and, in this case, possibly contributed to the decline of a threatened species, the scientists say.

“The increase in mesopredators such as coyotes is a serious issue; their populations are now much higher than they used to be when wolves were common in most areas of the United States,” said William Ripple, a professor in the Department of Forest Ecosystems and Society at OSU.

“Before they were largely extirpated, wolves used to kill coyotes and also disrupt their behavior through what we call the ‘ecology of fear,'” Ripple said. “Coyotes have a flexible, wide-ranging diet, but they really prefer rabbits and hares, and they may also be killing lynx directly.”

Between the decline of their central food supply and a possible increase in attacks from coyotes, the Canada lynx has been in serious decline for decades and in 2000 was listed as a threatened species. It also faces pressure from habitat alteration, the scientists said, and perhaps climate change as lower snow packs further reduce the areas in which this mountain species can find refuge.

In numerous studies in recent years, researchers have documented how the presence of wolves and other large predators helps control populations of grazing ungulates including deer and elk, and also changes their behavior. Where wolves have become established, this is allowing the recovery of forest and stream ecosystems, to the benefit of multiple plant and animal species.

Lacking the presence of wolves or other main predators in both terrestrial and marine environments, populations of smaller predators have greatly increased. Other studies have documented mesopredator impacts on everything from birds to lizards, rodents, marsupials, rabbits, scallops and insects. This includes much higher levels of attacks by coyotes on some ranch animals such as sheep, and efforts attempting to control that problem have cost hundreds of millions of dollars.

Scientists have concluded that exploding mesopredator populations can be found in oceans, rivers, forests and grasslands around the world.

“In the absence of wolves, coyote densities and distributions generally expanded in the U.S., into the Midwest, to the northeast as far as Newfoundland, and as far northwest as Alaska,” the researchers wrote in their report.

Where wolves recovered, as in Yellowstone National Park, coyote populations were initially reduced by 50 percent, Ripple said. Although more sampling will be required, early evidence indicates that a snowshoe hare recovery may be taking place.

As these issues are factored into decisions about how to manage wolves, the researchers said, it’s also important to maintain what they call “ecologically effective” wolf populations, the researchers wrote in their study. The full value of these top predators, and the numbers of them it takes to achieve a wide range of ecological goals, should be more thoroughly researched and better understood, they said.

The issue of “mesopredator release” has been studied rather extensively in recent years.

My favorite study on mesopredator release happened in suburban Southern California.  Michael Soule found that in areas where suburban coyotes frequented, there were more songbirds. Why?   The coyotes in this environment where not the mesopredators. They were the apex predators, and they served the songbirds well. Domestic cats, both owned and feral, are known to be major predators of native birds, but in North America, their kryptonite is the coyote. Coyotes eat lots of cats in suburban environments. And the cats, not being fools, know to avoid areas where they might meet a coyote. It is in those areas of suburban Southern California where songbirds nest.  Coyotes really don’t care about bird nests, especially if they are up in trees, but they do care about cats.

In addition to the possible assistance that wolves could provide Canada lynx, it also been established that wolves have helped pronghorns fully establish themselves in Yellowstone.  When wolves were extirpated from the Yellowstone region, the coyote population shot up, and the coyotes began to take advantage of many different predation opportunities. When the female pronghorns dropped their fawns, the coyotes would swarm in and catch them. This predation prevented pronghorns from ever establishing the large numbers that had been expected for the species at Yellowstone.

When wolves were reintroduced, the coyote population was halved, and the coyotes tended to stay out of the open areas around the Lamar Valley, where the pronghorns gave birth to their offspring every year.

If wolves succeed in reducing the Canada lynx’s problems from coyotes, it will be a good thing for this species. It is not very common in the United States anymore, but it once ranged rather extensively through the northern tier and down the Rockies.

These lynx do exist in Canada at fairly large numbers, where there are also plenty of wolves. Wolves and Canada lynx really are not competitors. Canada lynx are almost entirely snowshoe hare specialists, and they tend to inhabit much more densely wooded places than wolves do.

However, coyotes do frequent these very densely wooded areas, and they are not above killing a lynx’s kittens.  An adult Canada lynx could kill a coyote on its own, but if confronted with a family group of coyotes, my guess is the lynx wouldn’t stand and fight.

The real problem with Canada lynx and coyotes is the same that existed between dingoes and thylacines. Canada lynx are too specialized to one species of prey, while coyotes are generalists, taking not only the lynx’s specialist prey but also other species, which allows their numbers to exploded. In Australia, the thylacines were specialized in hunting small macropods and other smaller prey, but when the dingo or proto-dingo arrived in Australia, they were able to hunt both large and small prey. They were able to take most of the thylacine’s prey from it and augment their diet with large macropods.

Specialization has proven to be the death of so many species, and it would be a shame if the generalist coyote would push the Canada lynx over in this fashion.

So maybe if the wolves do keep the coyotes down, the great northern cat can once again be on the increase.

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Source.

The goldens are working type dogs of the conventional sort, but the cockers are of the old-fashioned, long-backed strain.

Hey, they got a crow!

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Painting by George Horlor (1851).

The dog at his feet is a bloodhound, a dog that any Highland ghillie would need to track wounded deer.

The identities of the other two are less clear.

I think they are setters. Solid white and gold-colored setters were not unknown in the nineteenth century.

But then again, cream-colored and gold-colored retrievers were not unknown in the nineteenth century either.

Gordon setters were very similar to wavy-coated retrievers in conformation, and they were also known to come in the reddish gold color.

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Source.

The documentary is in German, but I don’t know where this was filmed.

Tiger sharks and blue whales are both wide ranging species.

This is not a big blue whale. It’s only about 60 feet long!

Nature isn’t always so nice.

This would be like a human being eaten alive by pack of weasels.

Not a great way to go.

 

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The following anecdote comes from Hutchinson’s Dog Breaking (1869).  The its veracity should be taking with a grain of salt, for it sound suspiciously like a violation of Morgan’s canon. However, it is an interesting story, for we do know that St. John’s water dogs often ate fish offal. They were also left to roam when they weren’t being used, and there are many accounts of them fishing along Newfoundland and Labrador’s shores, lakes, and streams.

The story goes like this:

At certain seasons of the year the streams in some parts of North America, not far from the coast, are filled with fish to an extent you could scarcely believe, unless you had witnessed it—and now comes the Munchausen story. A real Newfoundland [meaning St. John’s water dog], belonging to a farmer who lived near one of those streams, used, at such times, to keep the house well supplied with fish. He thus managed it:— He was perfectly black, with the exception of a white fore foot, and for hours together he would remain almost immoveable on a small rock which projected into the stream, keeping his white foot hanging over the edge as a lure to the fish.  He remained so stationary that it acted as a very attractive bait; and whenever curiosity attempted any unwary fish to approach him too close, the dog plunged in, seized his victim, and carried him off to the foot of a neighboring tree; and, on a successful day, he would catch a great number (pg. 267-268).

I think that is possible that a dog could figure out how to lure fish. However, it is also possible that this dog was just a very good stalker. Maybe the white foot was in the water just because that foot was dominant. The white foot may have been a lure, or maybe the black dog was just very hard for the fish to see.

My guess is that this dog learned how to stalk fish in Newfoundland, where being as still as possible on the shore was the only way to be successful.

We really don’t know what was happening here. The tendency to be quite anthropomorphic was fairly common in those days, but one should understand that Hutchinson wrote the book on training hunting dogs, especially retrievers.

So maybe this dog actually did figure out that his white foot was a lure, and Hutchinson reported it correctly.  Of course, it may have been a second-hand account, and Hutchinson may have never seen to dog stalk fish from the shore.

I think it was just a coincidence that the dog’s foot happened to be in the water when it stalked fish.

This dog was just a good fish stalker.

And to roam free and feed oneself on Newfoundland, one had to be a good hunter. That would probably was the reason why this dog was so good at taking fish from the shore.

***

This dog clearly appears to have been a St. John’s water dog. It is difficult to tell what kind of coat it had, but it appears to have had a longer coat than the later examples of his breed.

 

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This is the dog from the “Wildfowling on Lough Neagh” video that I wrote about earlier.

The dog is “just a mongrel,” but the narrator calls him the “best retrieving dog [he’s] ever seen.”

I would venture to say that this dog is a golden retriever/Labrador cross, but it’s a brown-skinned yellow, something that would be uncommon in European golden retrievers.

It’s just a purpose-bred mongrel or crossbred retriever with a thick golden coat.

Everything about the dog say “I’m a retriever. Don’t ask for my papers. Now, just let me swim out and get you that duck.”

Whatever his pedigree, he is a relic of sorts.

At one time, all the retrievers were like this dog.

They were bred solely for performance.

They weren’t given a lot of fancy training, but they did their job.

The pedigree didn’t matter.

They were retrievers.

No certificate told them what they were.

Only the splash into the cold water and the struggling wounded duck revealed their identity.

That’s the way it is with this retriever.

Whatever he is exactly doesn’t matter; he is a retriever.

And that’s all we need to know.

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This image comes from The Shotgun and Sporting Rifle (1859) by John Henry Walsh (Stonehenge).

The dog on the left is the Southern Irish water spaniel or McCarthy’s strain. It is the same breed that we call “Irish water spaniel” today.

The dog on the right is the Northern Irish water spaniel, and it is quite different.

Walsh describes the breeds in his text:

Of the Irish Water Spaniel there are two kinds:  the North of Ireland dog, which is given in the annexed engraving; and the South Country water spaniel, of which I have never seen a well-marked specimen. Both are of a liver colour, but the former has often more or less white, while in the latter this is entirely absent. The northern dog is also longer on the legs, with short ears, having little or no feather on them, and both the legs and tail being also almost free from this ornament, and covered instead with a short curly coat, as is also the rest of the body. The southern dog, on the contrary, has long and well-feathered ears, tail round also, and pointed, never being carried above the back; head covered with a perfect top-knot, coming down over the forehead in a peak. These dogs are valued very highly in Ireland, but they are little known out of that country. The northern Irish spaniel is, however, common enough in England and Scotland (pg 145-146.)

If one reads that last sentence a bit carefully, one can see what happened to the Northern Irish water spaniel. It was so celebrated as a retriever in Scotland and Ireland that it was absorbed into the retrievers.

It is much more likely that the curly-coated retriever, which is always said to have Irish water spaniel ancestry, owes a lot to the Northern Irish water spaniel for its ancestry, than the Southern Irish water spaniel, which became much more common as the institutionalized fancy developed.

It is sometimes suggested that the Tweed water spaniel or Tweed water dog was the closest relative to the Norther Irish water spaniel, which itself could probably more accurately be called a water dog rather than a water spaniel. Both of these dogs resembled retrievers and St. John’s water dogs more closely than other water spaniels.

The exact origins of the Northern Irish and Tweed breeds are not well-established, although there is at least one account that says that the Tweed water spaniel was a cross between a water spaniel and a “Newfoundland,” probably the St. John’s water dog. That means that it was an early regional variant of the curly-coated retriever.

If that is the case, then it is probable that the Northern Irish water spaniel was also a cross between some kind of indigenous water spaniel in the North of Ireland and the St. John’s water dog, which was itself occasionally liver in color. The St. John’s breed was almost always marked with white on the feet and chest as we can see in the depiction of the Northern Irish in Stonehenge’s text.

The curly-coated retriever was always a St. John’s water dog crossed with some sort of water spaniel. There are actually two other breeds that were of that exact same cross, although the regional variant of water spaniel was often quite different. In addition to the Tweed, the Norfolk retriever was known to be a cross between the water spaniel of East Anglia and the St. John’s water dog. This breed began to standardize, and it competed in retriever trials up until the First World War.  What happened to it is unknown.

It is possible that the standard curly-coated retriever absorbed it, as I highly suspect happened with the bulk of the Northern Irish water spaniel breed.  But it is just as possible that it became extinct.  Large-scale dog breeding went on hiatus during both World Wars, and if there were not many of these dogs around before the war started, it is very possible for them not to survive the hiatus.

We don’t know how the Northern Irish water spaniel developed. It might even be one of the ancestors of the St. John’s water dog, but I think that if it was known that Tweeds were “Newfoundland”/spaniel crosses, it is possible that this breed had a very similar make-up.

 

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