April 20, 2018

Meta-Analysis, Coyotes, and Lyme Disease

Recently I had posted a link to a “study” conducted at Pepperdine University about the diet of Northeastern coyotes, compared to Western coyotes’ and a possible link to the spread and/or perpetuation of Lyme Disease in the Northeast.

On March 4, 2018, I wrote an article sharing, in part, the publisher of Maine Sportsman Magazine, Jon Lund’s, observation that the increased population of coyotes in Maine was causing an increase in Lyme Disease-carrying ticks which in turn was the cause of up-turns in the incidences of the disease. I wrote: “In the March 2018 edition, he asks, “Are Coyotes to Blame for Increase in Ticks?” His simple explanation is that the presence of an increased population of coyotes in Maine is causing a reduction in the fox population – the trickle-down effect of an increase in ticks, particularly the tick that carries Lyme disease. The reality is that coyotes compete with and kill, directly and indirectly, the red fox that is sufficiently more adept at killing the small rodents that carry and perpetuate the Deer (Lyme) tick. In an effort to mitigate what appears to be a festering and growing incidence of Lyme disease in Maine, Lund is wondering if it is time, due to the necessity of a public health risk, to make a more serious effort at reducing the coyote population.”

According to the Meta-Analysis linked to, their conclusions do not support Lund’s theory. While I only have the Abstract of the study, I can only provide what is written there. But first, let me explain something in case readers don’t know what a meta-analysis is. A meta-analysis is “a statistical analysis that combines the results of multiple scientific studies.” (Source)

In this instance, scientists simple took data from 18 different studies about coyote diet and determined that while coyotes in the Northeast readily ate more deer, they proportionately did not eat more or less small predators (like the fox that Lund claims eat the rodents that carry the Lyme tick). The Abstract states: “Our results show that deer occur significantly more in the diet of Northeastern coyotes than in the diet of Midwestern coyotes, while small mammals occur significantly less. The occurrence of rabbits, hares, birds, vegetation, and fruit do not differ significantly by region. This supports the hypothesis that Northeastern coyotes, due to their larger size and hybridization with wolves, are better adapted at hunting large prey. Although Northeastern coyotes eat fewer small mammals than Midwestern coyotes, small mammals are still a common component of the Northeastern coyote diet. Thus the abundance of Northeastern coyotes is not likely to be positively correlated to the incidence of Lyme disease.”

It’s worth pointing out a few things. Again I’ll state that I don’t have access to the full study, however, there does seem to be some degree of contradiction but that contradiction may be insignificant.

Second, it appears from this information that because the Northeastern coyote eats far more deer, due mostly in size and cross-breeding with wolves, it may be due to a bigger appetite because the animal was bigger than the Western coyote. A conclusion on my part.

Third, this information clearly states that Northeastern coyotes eat fewer small mammals than their Western counterparts, but evidently not enough to make any sort of difference.

Fourth, this study concludes that it is “not likely” fewer small mammals consumed “positively correlated to the incidence of Lyme disease.”

It would appear that this analysis has only proven that Northeastern coyotes eat more deer than Western coyotes.

There is nothing conclusive, that I can see, that the presence of an increased population of coyotes has no effect on Lyme ticks.

Do any of the studies have data that go back to a time before the “Eastern coyote” became an invasive species? Have any of these studies taken place in long enough periods of time to take into account a changing coyote diet due to changing conditions on the ground? In other words, depending on conditions on the ground, a coyotes’ diet can have large fluctuations in amount and prey diet. Are these factored in? Will a changing diet also change the incidence of Lyme disease?

There are a lot of questions that remain unanswered. Because of this meta-analysis, I wouldn’t be too quick to disregard Jon Lund’s hypothesis about the direct correlation between coyotes and Lyme disease.

What got along superbly before the invasive species arrived. I would surmise we could get along marvelously without them now.

 

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A Call for a Possible Bounty on Coyotes Because of Disease Spread

Jon Lund is the owner and publisher of the Maine Sportsman magazine. In the March 2018 edition, he asks, “Are Coyotes to Blame for Increase in Ticks?” His simple explanation is that the presence of an increased population of coyotes in Maine is causing a reduction in the fox population – the trickle-down effect of an increase in ticks, particularly the tick that carries Lyme disease. The reality is that coyotes compete with and kill, directly and indirectly, the red fox that is sufficiently more adept at killing the small rodents that carry and perpetuate the Deer (Lyme) tick. In an effort to mitigate what appears to be a festering and growing incidence of Lyme disease in Maine, Lund is wondering if it is time, due to the necessity of a public health risk, to make a more serious effort at reducing the coyote population.

Maine got along just fine before the coyote took over the countryside and contrary to the many statements made otherwise, we don’t need them.

However, there is something else I’d like to touch base with readers about that Mr. Lund brings up in his article. This has to do with the use of chemicals and/or “natural” elements to ward off ticks and insect bites.

I’m sure that the pharmaceutical industry, and anyone else who stands to make a profit from their drugs to treat Lyme and other diseases, has thoroughly hyped the presence of ticks and instilled ample fear into the masses. After all, when the people live in fear they will do most anything.

Lund speaks specifically about permethrin. Permethrin is a common ingredient found in compounds marketed as insect repellents or killers. Basically, it attacks the central nervous system of insects.

Permethrin is a synthetic, or man-made, product derived from pyrethrin.

Most fact sheets available to the consumer paint the picture of permethrin/pyrethrin as mostly harmless even though long-term effects have not been studied. Some believe that using products that contain permethrin presents a higher risk of health issues than the odds of getting bit by a tick that will infect you with Lyme or other diseases. This is something you will have to decide for yourself. But to make that decision honestly, you should make the effort to understand the presented “remedies” and “threats.” It’s your health. Know what you are doing.

Lund takes the time to explain how ticks are spread around (I don’t find any factual claims that global warming is the culprit) and refers to a study where “…a growing body of evidence suggests that Lyme disease risk may now be more dynamically linked to fluctuations in the abundance of small-mammal hosts that are thought to infect the majority of ticks.”

The same study tells us that the incidence and presence of Lyme disease are not related to the abundance of deer but to the absence of key small predators. “We then show that increases in Lyme disease in the northeastern and midwestern United States over the past three decades are frequently uncorrelated with deer abundance and instead coincide with a range-wide decline of a key small-mammal predator, the red fox, likely due to expansion of coyote populations. Further, across four states we find poor spatial correlation between deer abundance and Lyme disease incidence, but coyote abundance and fox rarity effectively predict the spatial distribution of Lyme disease in New York. These results suggest that changes in predator communities may have cascading impacts that facilitate the emergence of zoonotic diseases, the vast majority of which rely on hosts that occupy low trophic levels.”

This claim is in direct contradiction to the theory that predators kill only the sick of the prey species and justifies the “need” for predators to keep our ecosystems healthy. Not only is there no evidence that the presence of large predators reduces the presence of disease in ecosystems, this study seems to prove the exact opposite.

We forget or never learned history. Large predators like wolves and coyotes were not tolerated on the landscape by early settlers. And there were reasons for that, some of which include not only the destruction of property caused by these critters but it was known that they carried and spread diseases, many of which are harmful and even deadly to humans.

And yet, today, there is an all-out effort to protect these same predators. It appears that for some anyway, the demand for an abundance of coyotes at the expense of public health is just fine and dandy. I don’t see it that way at all and I’m not alone.

As the trend continues in the direction that it is headed, it should be fairly easy to predict there will be increased fall-out about protecting any animal that spreads dangerous diseases among the people. Few tolerate the presence of rats knowing and remembering the unbelievable death and destruction caused by the bubonic plague. Is there a difference in protecting the health and safety of the public because one culprit is a nasty rat and the other is a nasty wild dog?

Mr. Lund is correct in asking the question about the role of coyotes in Maine, or anywhere else, where, according to provided data, the coyote is directly affecting the growth, perpetuation and spread of Lyme disease.

If Maine cannot effectively control the population of coyotes for public health and safety with the current management strategies, then it may be time to look at something more effective.

It is dishonest by the many who blame hunting and trapping for the decimation and/or extirpation of wolves and coyotes but go out of their way to deny that hunting and trapping of the same animals today have any effect on reducing their population numbers.

Many decades ago when it was decided by governments that wolves and coyotes were destroying property and spreading diseases, one of the elements employed to rid the landscape of the nasty canines and the diseases they spread was a bounty system. Any bounty must be attractive enough to draw enough to the plan. What is the limit in the cost of healthcare?

Such a suggestion will be vehemently opposed by many, especially those who hate hunting and trapping. They are wrong that think people like Jon Lund and myself might promote a bounty system for coyotes only for improving deer hunting. Little do these people know and understand the real conservation of wildlife.

In the normal world which is being left in the dust, there would be no question as to what is the right thing to do. Normalcy tells us public health and safety take precedence over animals and the spread of disease. One has to wonder what the extent of the bubonic plague would have been like if people had known and took real action to get rid of the rats that spread the disease.

But, we live in a Post-Normal world now where many things are upside-down. Are we to wait until more and more people get sick and die before we begin to act? Are we serious about finding a cure to a problem or is there just too much money to be made along with the genocide many promote?

It appears so.

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Recolonizing Gray Wolves Increase Parasite Infection Risk in Their Prey

Abstract

The recent recolonization of Central Europe by the European gray wolf (Canis lupus) provides an opportunity to study the dynamics of parasite transmission for cases when a definitive host returns after a phase of local extinction. We investigated whether a newly established wolf population increased the prevalence of those parasites in ungulate intermediate hosts representing wolf prey, whether some parasite species are particularly well adapted to wolves, and the potential basis for such adaptations. We recorded Sarcocystis species richness in wolves and Sarcocystis prevalence in ungulates harvested in study sites with and without permanent wolf presence in Germany using microscopy and DNA metabarcoding. Sarcocystis prevalence in red deer (Cervus elaphus) was significantly higher in wolf areas (79.7%) than in control areas (26.3%) but not in roe deer (Capreolus capreolus) (97.2% vs. 90.4%) or wild boar (Sus scrofa) (82.8% vs. 64.9%). Of 11 Sarcocystis species, Sarcocystis taeniata and Sarcocystis grueneri occurred more often in wolves than expected from the Sarcocystis infection patterns of ungulate prey. Both Sarcocystis species showed a higher increase in prevalence in ungulates in wolf areas than other Sarcocystis species, suggesting that they are particularly well adapted to wolves, and are examples of “wolf specialists”. Sarcocystis species richness in wolves was significantly higher in pups than in adults. “Wolf specialists” persisted during wolf maturation. The results of this study demonstrate that (1) predator–prey interactions influence parasite prevalence, if both predator and prey are part of the parasite life cycle, (2) mesopredators do not necessarily replace the apex predator in parasite transmission dynamics for particular parasites of which the apex predator is the definitive host, even if meso- and apex predators were from the same taxonomic family (here: Canidae, e.g., red foxes Vulpes vulpes), and (3) age-dependent immune maturation contributes to the control of protozoan infection in wolves.<<<Read More>>>

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Coywolves in Maine Using Wolf Tactics To Bring Down Healthy Buck

The below photograph was sent to me from people I know in Maine. It was taken with a game camera from a location in Eastern Maine.

We know that genetically the wild dogs in Maine are a hybrid mixture of coyote, wolf, feral dog and domestic dog. It appears from this photo and others similar to it that I have seen, that Maine’s “coywolves” certainly have inherited more size and hunting tactics employed by wolves to bring down large prey such as the nice mature, healthy buck shown in the picture.

The myths of predator/prey relationships perpetuated by the ignorant believe that wolves/coyotes only kill sick prey and have no idea that this is simply not true or how the wild dogs go about eating and killing their prey while the prey is still alive, as is depicted in this photograph. For this kind of hunting, there is no such thing as an instant or “humane” kill.

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Photography: Buck Out-swims a Hungry Wolf

Please follow this link to view some photographs of a wolf swimming after a buck across a lake. The wolf takes a bite but is unsuccessful in bringing down the buck.

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It Happens Every Spring

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Bears are Bigger Killers Than Thought

*Editor’s Note* – When media crafts these headlines, it would be nice if they were a bit more accurate and explicit in whom they are referring when they write: “Bears are Bigger Killers Than Thought.” Thought by whom? I didn’t think they were sparse eaters of such things as moose, caribou and even cannibalism. Perhaps maybe, scientists are catching on a little bit instead of relying on Bambi and Yogi Bear to determine who kills and eats what.  

Overall, the bears [just seven of them] killed an average of 34.4 moose and caribou calves over 45 days. That’s far higher than average kill rates from previous studies using other methods, including aerial observation. Compared with one 1988 study in which scientists counted an average of 5.4 moose calf kills from the air in a different part of Alaska, the new study found an average of 13.3 moose calf kills. The new study also found wide variation in the number of calves killed by any one bear, with one killing 44 calves in 25 days and another killing just seven in 27 days.<<<Read More>>>

I wonder what cameras on wolves would reveal?

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And People Think Little Red Riding Hood is a Fairy Tale

This not only is a fairy tale, but it’s the biggest lie of the century.

“Phillips described the benefits of wolf recovery in terms of a “trophic cascade.” Essentially, that the reintroduction of wolves in Western Colorado will have a widespread effect resulting from the predation of elk. Most directly, it has the potential to cleanse the herd and mitigate the prevalence of chronic wasting disease. If wolves have a “big enough effect on prey, it can benefit willows and Aspens for example. They can grow more robust and many species can benefit from that,” he said.”<<<Read More Nonsense>>>

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Can coyote predation risk induce reproduction suppression in white-tailed deer?

Abstract

Predators can have powerful nonconsumptive effects on their prey by inducing behavioral, physiological, and morphological responses. These nonconsumptive effects may influence prey demography if they decrease birthrates or increase susceptibility to other sources of mortality. The Reproductive Suppression Model suggests that iteroparous species may maximize their lifetime reproductive success by suppressing their reproduction until a future time, when conditions may be more favorable. Coyote (Canis latrans) range expansion in the United States has exposed white-tailed deer (Odocoileus virginianus) populations to increased predation risk, and coyote predation can have profound effects on white-tailed deer reproductive success. We evaluated effects of temporal variation in predation risk (i.e., coyote–deer ratios) on fecundity and reproductive success of white-tailed deer on the Joseph W. Jones Ecological Research Center in southwestern Georgia, United States, by exploiting a rapid decline in coyote abundance to establish a natural experiment. We measured fecundity by examining ovaries for evidence of ovulation, and measured reproductive success using evidence of lactation from deer harvested before and after the decline in coyote abundance. We found that incidence of ovulation and lactation increased following the decline in predation risk. Our results suggest coyotes may be able to influence deer recruitment, independent of direct predation, through interactions that result in reduced fecundity. More broadly, our study suggests that in order to understand the totality of the effect of predators on prey population dynamics, studies should incorporate measures of direct and indirect predator effects.<<<Read More>>>

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Armed Prey

PreyArmed

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