*Editor’s Note*: Below I have republished an article I wrote in February of 2012 called, “Are Winter Ticks Killing Maine’s Moose Population?” I have edited this report to update bad links and to remove some information that is not exactly that relevant to current events.
The point of republishing the article is in response to the recent announcement that the Maine Department of Inland Fisheries and Wildlife (MDIFW) is going to reduce available moose permits this late summer and fall by nearly 30% due to a significant die-off of moose during the most recent winter event. The responses to this announcement are mostly based on bad information, especially coming from those who believe the increased number of ticks killing moose is attributed to “global warming”; conveniently that term has been changed to “climate change” in order to fool more people. Persisting in the mantra of climate change is dishonest at best and shows ignorance to an understanding of the life cycle of the winter moose tick and what environmental and biological conditions effect the tick.
Burying our heads in the sand and blindly following climate change as the excuse du jour is partly a product of socialized wildlife management. Socialized wildlife management began when our wildlife managers abandoned sound and scientific animal biology and replaced it with social tolerances and desires of the public in what they wanted for wildlife in their neighborhoods. This, of course, is utter nonsense and is often referred to as “Romance Biology” – that is a form of fantasy or idealistic coexistence with animals based on some mythological notion that nature will balance itself if man would just shrivel up and go away.
In addressing Maine’s moose herd, we know that over the past several years, people have clamored and whined to the state that they wanted more and more moose to “watch”; some even claiming huge money to be made with moose watching tours. But is this social demand for more moose biologically sound?
It is my theory, and I’m not alone in these thoughts, that following the attack of the spruce budworm that resulted in the clear-cutting of hundreds of thousands, perhaps millions of acres of infested forests, the resulting landscape, as the forests regenerated, made for prime moose habitat, as well as habit for the snowshoe hare which helps explain the resurgence of Canada lynx.
Maine’s moose population grew rapidly and without definite tools at the disposal of moose managers, it was only educated guesstimates used to determine what might have been a reasonable number of moose. We should have known things were growing too fast when the state had to offer moose hunting permits in some southern Wildlife Management Districts. With recent aerial counts we now have a better idea.
In the link that will appear below of work done by William Samuel about moose ticks, Samuel provides a map that shows where moose ticks appear. The map also shows the range of the moose and as most of us know the moose in Maine are at the southern end of the range. For that reason alone shouldn’t we be concerned that a moose population that has grown to an official count of 75,000, with some estimations up near 90,000, that this is not normal?
If MDIFW is going to continue to guide their wildlife management by social demands, the future and health of wildlife populations can probably expect more of disease, parasite, worms and other infestations.
As is pointed out in the republished article below, maybe instead of reducing the moose harvest to keep number artificially high, we should considering an overall reduction in population. William Samuel does say that more moose mean more ticks. After all, ticks thrive when there are a lot of hosts to suck blood from.
Are Winter Ticks Killing Maine’s Moose Population?
There seems to be a bit more information about winter ticks that I haven’t found in any Maine publications that deals more in depth with what happens in the fall when the winter tick larvae are gathering on vegetation waiting for a free ride with a host. In addition to that, while these winter ticks effect all wild ungulates, why pick on the moose so much. And, it is said that the winter ticks don’t actually kill the moose, but rarely, are we looking at an honest assessment of all factors that kill a moose weakened by tens of thousands of blood sucking ticks?
Lee Kantar says that the winter tick is a “huge contributor” to the death of some moose, he also points out that, “it’s not the sole cause”. Even on the MDIFW website [Note: the original link is no longer valid after MDIFW redesigned their website. In it’s place MDIFW links to an off-site location for information about winter ticks.], information provided about moose states that, “winter tick and lung worm infestations rarely kill moose”.
This information is supported in existing studies about moose and winter ticks. William M. Samuel and Dwight A. Welch, “Winter Ticks on Moose and Other Ungulates: Factors Influencing Their Population Size,”[Once again the original link I had on studies by William Samuel and Dwight Welch is no longer valid. The actual study now is behind a pay wall. I will provide here a link to a preview of a book with the title I’ve shown. It is in this preview where the map of where moose ticks prevail is available.] states that winter ticks (dermacentor albipictus) being the cause of death isn’t certain because, “unequivocal evidence is lacking”.
I think therefore it might be honest to conclude that the cause of death in the majority of dead moose being found in the Maine woods that are inundated with ticks, was not the tick alone. There had to have been other factors. We’ll address those in a moment.
First I think it important to better understand what takes place in the fall of the year. We have read statements from biologists and outdoor sportsmen that seem to indicate that Maine needs little snow and very cold temperatures to kill off the ticks. While that may be true it’s not the entire story in the life cycle of these ticks.
Samuel and Welch state that for there to be significant die-offs of winter ticks, you need 6 consecutive days in which the temperature does not exceed 1.4 degrees Fahrenheit. This is not the only way to kill the ticks and/or lessen the severity of ticks on moose.
During the fall months, in Maine’s climate around September and October, the winter tick larvae find their way onto vegetation. They clump together on the ends of small branches etc. These larvae can be found on vegetation just above the ground to quite high up in trees. The larvae wait until a passing, warm-bodied host, in this case a moose, passes by and then they attach themselves to the moose and the ride begins. You can read all the splendid details by reading the studies, etc.
It is during this time of year, September/October, that certain weather events can have a significant effect on how severe the tick season will become. Early cold temperatures, especially those below freezing, will greatly reduce the activity of the larvae, i.e. limiting their effectiveness of attaching themselves to the moose or even migrating up the stems of vegetation.
Early snows can bury the larvae and stiff fall winds will blow the larvae off the vegetation scattering it around and to the ground preventing the larvae from being able to find a host. The studies of Samuel and Welch, as well as others [original link can no longer be found], seem to agree that the weather events of the fall have a greater effect on tick production than hoping for enough snow and cold in winter to kill the ticks. Without a host, the larvae die.
There are other interesting things to be discovered about moose and winter ticks. For example, these winter ticks bother all wild ungulates, i.e. deer, moose, elk, etc., but most scientists will agree that it seems to be the moose that is the most effected. It is assumed that it all has to do with timing.
The aggregation of the larvae on vegetation seems to more closely fall in line with the timing of the moose mating season. During this time, moose are most active, covering greater amounts of territory than normal and male moose travel more than the females and thus explains the observation by some that it seems bull moose are more effected by the winter ticks than cows. I believe this conclusion about bull moose vs. cow moose is based on assumptive reasoning than anything concluded through scientific study.
In the Samuel/Welch study, experiments were conducted and it was determined that moose have an aversion to larvae/tick infested food. Imagine if they didn’t. If moose have an ability to smell or sense the larvae on the vegetation and in their food, it might also help to explain the claims of some and what is obvious on the ground that predators and scavengers won’t touch the dead carcass of a tick infested moose.
Studies have shown us that there can exist tens of thousands of ticks on any one moose and that this number of ticks can certainly put the moose into a weakened state. Moose are already in a weakened state just trying to survive the winters. Compound that with 50,000 ticks and the problems snowball. However, as we have learned, the ticks alone rarely kill a moose but certainly contribute to it.
When the blood sucking begins, the moose spends much of it’s time “grooming”. Studies tell us that moose that are troubled by the biting ticks do not bed down as often nor as long as non infected moose. This of course tires the animal even more.
While studies seem to be lacking on exactly what happens to the composition of the moose’s blood while all these ticks are feasting, it is honest to assume that the more female, blood sucking ticks there are on a moose, factoring also the moose’s body mass, the greater a weakened state is realized due to loss of blood.
All of these factors and more, make the moose more vulnerable to all the other elements that contribute to normal winter kill. In other words, it becomes more difficult to get enough nourishment; loss of blood and reduced winter hair makes the moose more susceptible to hypothermia; spending so much time “grooming” expends valuable energy needed for survival and with all these losses a moose certainly could not ward off attacks and harassment by predators.
This is perhaps where I’ll get ambushed but please consider the facts and possibilities. There is no denying that coyotes/wolves will harass and kill moose, deer and elk during their weakened winter states. Even though it is seen and believed to be accurate that predators and even scavengers will not touch a tick-infested moose carcass, at what point does a pack of hungry wolves/coyotes know their target is tick infested.
Some of us have been made aware through written and video accounts of how these predators take down and kill, often eating alive, their prey. We have also seen videos and photographs that document coyotes and wolves chasing down their prey. How long could a moose, weakened by normal winter strains and tick infestation, last in trying to run away from a predator attack? Not long I’m afraid. Would the moose have survived if the predator wasn’t there? There’s no way of knowing the answer to that question.
Which brings us once again back to the same point about predators. It seems that when all things within our forests are going well, little concern is given to predators and the effects they have on our game animals. When things get skewed, those populations of predators loom large over the forests and can raise some serious cane even to a point of prohibiting the rebuilding of a herd of deer or moose, in this case a herd that might be suffering some from these blasted ticks.
So, what do we do about the ticks? What can we do? In one report a gentleman suggested some kind of spraying program to kill the ticks but I’m not sure how feasible that is or if that’s something we want to pour onto our landscapes. We can’t control the weather but we can control the predators. But, is that the answer either to this exact equation?
In George Smith’s blog post yesterday, he explained that one Dr. Anthony who attended a recent information session on Maine’s moose, suggested that instead of trying to limit hunting permits for moose to protect them due to increased mortality from ticks, that killing more of the moose might be the better solution.
I’ll leave you with some questions. Feel free to chime in below in the comments section with some answers.
1. According to George Smith’s blog post I referenced above, in 2007 the estimated moose population of Maine was 45,000. Now Lee Kantar, Maine’s head deer and moose biologist claims there are 75,000 or more. Are there now too many moose in Maine which is exacerbating the tick problem?
2. If so, do we kill more moose during the moose hunt? Or do we protect more moose?
3. George Smith states that the new moose counts are, “more credible than any previous estimates”. He offers no substantive proof of his claim. Do you think the new counts are more “credible” or accurate than previous and why?
Who would have thought 35 years ago Maine would be asking if the state had too many moose?
