By Josh Leavitt

Western Wildlife Ecology

©2014 by Josh Leavitt. All rights reserved.

The following is the response to the question of the potential effects of GMOs on deer.

I started studying the last 20-30 years of mule deer declines here in Utah a few years ago. This expanded into looking at the declines of mule deer, bighorn sheep, moose, and wildlife in general across the Western United States during that same time frame, as they are synchronous. My focus is still mule deer. Living on a mule deer winter range, I grew up hunting mulies.

Keep in mind that the vast majority of GMOs are what is known as “roundup Ready.” They are genetically engineered to be able to resist the affects of the herbicide Glyphosate. Those GMO crops utilize large quantities of glyphosate in their production. It is not so much that these plants are genetically modified that is the problem or the danger to deer, but rather the techniques and chemicals used when growing them.

Glyphosate is a chelator, meaning it binds up and makes minerals unavailable. That is how it kills plants. It deprives them of nutrients and they succumb to disease.

When I first started looking into this, I was working on access issues in the Wind River Range of Wyoming. There was a proposal that ultimately blocked the use of pack goats into the Wind Rivers, because of concerns about disease transmission from pack goats to bighorn sheep. Looking into those issues of bighorn sheep declines set me on the track I am on now. As I studied the history of bighorn sheep declines, it was like I had already read much of it in respect to the nature of sharp declines with subpar rebounds. The time frame followed perfectly with mule deer.

This led me to the work of John Mionczynski. John is the Adolph Murie of bighorn sheep. His work with bighorn sheep in Wyoming narrowed down the sharp population crashes, and declining sheep herds to selenium deficiencies that were causing White Muscle Disease and other selenium response disorders. They observed bighorn ewes that were suffering from White Muscle Disease and could not nurse their lambs. These ewes would travel several thousand feet, over long distances down the mountain, to a natural salt lick. When they returned to their lambs, the ewes were better. And when the afflicted lambs nursed they also improved.

John and his colleagues, including Joe Hutto (Author of “The Light in High Places” and “Touching the Wild”) began to look into the feed and nutrition of the sheep. They were able to show that selenium deficiencies were driving these declines. They were able to show that nitrate deposition in spring rains drove the availability of selenium in the feed of the sheep. They were able to reproduce this with controlled experiments. In dry years when the feed did not receive those spring rains the sheep population would stabilize and begin to increase, but they have never recovered. Bighorn sheep declined by some 90% across large portions of the West. Here are related links to the work:

When nitrate pollution fell on the feed of bighorn sheep, the selenium content of the feed declined. One of the things that led to this was a fungus that volatilized available selenium out of the soil into the atmosphere making it unavailable to the plants or the sheep. Glyphosate (Round up) has been shown to reduce beneficial soil funguses such as mycorrhizea that help to transfer nutrition into plants.

Glyphosate has also been shown to increase funguses like fusarium solani that adversely affect the mineral uptake by plants. Fusarium has the ability to methylate selenium out of the soil. It is being used to remove dangerously high levels of selenium from soil in California. Consequently, glyphosate increases the occurrence of bad fungus and reduces the occurrence of good fungus, with additional factors like nitrate deposition compounding the problem by feeding the bad fungus.;jsessionid=0D7177766842AD478AECA6DA37817690;jsessionid=04E08AEFDCAD6271FD48E107ABC36C1F

So that is one way in which Glyphosate could indirectly affect big game animals that have followed the same population dynamics as mule deer throughout the West. Moose are a species that is of course much more closely related to mule deer. Moose populations have followed the same pattern of declines over the last 20-30 years as bighorn sheep and mule deer. One of the things that they have in common with bighorn sheep declines is mineral deficiencies notably selenium and copper. In conjunction with these mineral deficiencies, moose have experienced large parasite loads such as liver flukes and brain worms.

Glyphosate (roundup) has been shown to influence parasite loads and life cycles. This has then been shown to affect both fish and terrestrial animals. In this first case, glyphosate has been shown to affect the life cycle of snails and the parasite worms that use them for part of their life cycle. This leads to a decline in fish species affected by the increase in parasite load brought on by the glyphosate. This particular example was studied in New Zealand. We have seen a similar situation with whirling disease here in the United States, and its occurrence follows the same time frame and cycle of mule deer, bighorn sheep, and moose numbers.

Another example of this is the way in which glyphosate influences another snail and the parasite that it carries. In this case Glyphosate increases Pseudosuccinea columella Snails, that carry Fasciola hepatica. Fasciola hepatica are liver flukes. So we have increased use of glyphosate over the last 30 years, with declining moose populations suffering from mineral deficiencies and high parasite loads such as liver flukes, all of which glyphosate has been shown to be able to influence. Here in Utah our subalpine ponds that used to be full of frogs, toads, and salamanders, have none, but there are a lot of snails, and further declining moose populations.

Bighorn sheep also suffer from snail related parasite problems. In the last 30 years, pneumonia has been one of the leading causes of bighorn sheep declines in the West. Lungworms that have led to pneumonia enter the sheep via a snail host that they ingest while eating. The snails are carriers of the lungworm. Just like with the fish in New Zealand and the snails that carry liver flukes.

Then we look around at the prevalence of “cactus” bucks, and skewed Buck to does ratios, in favor of bucks. The affect of increased buck to doe ratios has been shown to suppress deer populations when induced though management techniques. So in the case of skewed buck to doe ratios at birth, you would see a similar suppression of deer numbers. When deer are experiencing male reproductive malformations, such as those documented by Judy Hoy in Montana, deer also experience skewed sex ratios at birth, in favor of male animals. This becomes one part of suppressed and declining deer numbers. Skewed sex ratios can be affected by a number of factors, including nutrition and exposure to endocrine disrupting chemicals. Many pesticides have been shown to be endocrine disruptors. Glyphosate has been shown to disrupt male reproductive function and affect fertility.

The increase of cactus bucks across the West has risen in recent years, with an onset approximately 20 years ago. These cactus bucks are typically cryptorchid, meaning that their testicles have not descended. Many are infertile and incapable of breeding. Cryptorchidism is typically caused by endocrine disrupting agents that affect the masculinization window during gestation. This has been seen on Kodiak island in Alaska, in Sitka black tailed deer where low lying areas have greater frequency of this birth defect, leading to many people looking to causes from the ocean. The fungicide Chlorothalonil was found in all fog samples in the Bering sea during a USGS survey, just like it has been found it rain, surface water, and air samples, in the Bitterroot valley of Montana. Anti-fungals get used at higher rates when glyphosate is used, because of the bad fungal infections that glyphosate increases. Additionally, there appears to be adverse synergistic affects on animals that are simultaneously exposed to Glyphosate and Chlorothalonil.

Cryptorchid males have also shown up in other places as well. The rate and frequency of occurrence demonstrate that it is an environmentally driven problem, going beyond natural variation and occurrence. The following are examples of clusters of cryptorchidism, besides the Alaska cases Oregon: Washington: Colorado: And in Wyoming, Joe Hutto  has seen velvet retention and non breeding bucks in the mule deer he has been studying for the last 8 years. When I visited him earlier this year, he had examples of antlers that were being shed that still retained their velvet. That one was new to me.

Glyphosate has been found in as much as 75% of rain, water and air samples taken from across the Untied Sates.

The cases of cryptorchidism occur sympatrically with other reproductive malformations and cases of congenital fetal hypothyroidism, indicated by multiple birth defects, especially underbite and overbite. They follow the same patterns of declines, and subpar recoveries seen in mule deer, moose, and bighorn sheep populations. If glyphosate can disrupt male reproduction after birth, it would be reasonable to conclude that it could disrupt male reproductive morphology during the masculinization window on a male fetus, as even less of a dose should be required for disruption.

Then you have the more direct affects, such as bioaccumulation in the bodies of animals. Such as in the case of cattle in Denmark that have been shown to have serious mineral deficiencies and organ damage from eating GMO feed. Also see If it is bad for cows, it is bad for deer and other ruminants.

So the question is not so much, what GMOs could do, but what their cultivation, with the use of Glyphosate is already doing. We have not even gotten into the newer GMOs on the horizon that utilizes 2,4,D, which is chemically very similar to 2,4,5-T (the other half of the Agent Orange formula), which 2,4-D replaced. Also keep in mind that many of the affects of Glyphosate are secondary or synergistic with other compounds, leading to varied outcomes by region based on conditions, synergistic compounds and the other species in the ecosystem that are affected. The entire ecosystem and time frame must be looked at to see the full affects.

In short, mineral deficiencies, increases in pathogens, parasites, malformations and resultant wide scale wildlife declines are the affect of the planting of GMOs. They are bad for deer and deer hunters.