By Bob Ferris
My wife and I are fans of the Lord of the Rings trilogy. For us that meant that we recently re-watched the extended versions of the three movies and also spent time watching the special features disc associated with each film. The former was still great and the latter was revealing in so many ways. One of the things we learned on the special features disc was how some of the special effects were accomplished both during shooting and with post-production wizardry. Pretty cool stuff.
One interesting element of this was how they were able to deal with the size differences between the smaller hobbits and dwarfs and the larger humans and elves. Once you understand that “little people” actors in prosthetics were used in the wider shots containing both big and small characters it really changed your perspective. You actually could start to identify the various small actors who served as costumed and masked doubles in these scenes by their gait and movements. Once you gained this knowledge and knew what to look for it was easy to spot the cinematic sleight of hand when it was employed. It did not take anything away from the movie experience in fact it really seemed to enhance it.
This whole episode got me thinking about wolves and why what is so obvious to those who have had ecological and biological training just may not be that accessible to others without the same grounding. Maybe we need a “special features” disc for the wolves? But what would be on that disc? What is missing from the anti-wolf crowds understanding of the bigger picture?
To begin to understand what should be on the disc, perhaps we should visit the most notorious example cited by anti-wolf parties and trophy hunters—the Northern Yellowstone elk herd crash. For the last couple of years all we have heard from the David Allens, Bob Fannings and Don Peays of the world are how wolves were released and immediately decimated this famous and very visible elk herd. It is almost like these anti-wolf advocates had their own “remember the Alamo” moment. But we need to inject a little of the late Paul Harvey here and start to look at the rest of the story.
That examination begins with looking at the long term elk population trends in Yellowstone’s northern range. Important milestone events to remember to help make sense of this are that wolves were basically gone from the system by the mid-1920s, Park staff culled elk herds until 1968 when hands-off or ecological management became the rule, the massive Yellowstone fire happened in 1988, and wolves were first re-introduced to Yellowstone in 1995.
Bearing all of this in mind, here is what would likely make the short list for inclusion on “Special Features Menu” for the Northern Yellowstone elk herd or subpopulations like the Gallatin:
"Elk summer-fall use declined after fire, then increased to levels nearly three times the level of the control before dropping back at the end of the 20-year period. Elk winter-spring use was higher than the control throughout the entire evaluation period, with the highest recorded post-fire use 7 years after fire." Effects of Fire in the Northern Great Plains
Post-fire Plant Succession: The Yellowstone fire of 1988 swept through the Park with a myriad of consequences. One of the most important ones for elk was that the fire opened up habitats and enabled an explosion of new plant growth which enabled the elk population to grow rapidly. As plant succession—the natural progression from the softer, more nutritious pioneer plants to woody plants—progressed the amount and quality of food in the Northern Range available to elk diminished.
Availability of Water: Water is a huge driver for elk as it has a consequential impact on the quantity and quality of vegetation. When precipitation is plentiful elk populations tend to grow and they decline in droughts. 
Competition with Bison and Other Species: Elk tend to displace deer but are in turn displaced by bison in Yellowstone and domestic cattle in other places where grazing is allowed. Bison populations have risen considerably over the past several decades ergo competition is likely another factor to consider. [1,2]
Grizzly Bears and Predators: Grizzly bears also prey on elk—particularly elk calves. Grizzly populations in Yellowstone have increased considerably over the last several decades. This puts additional pressure on the elk.
Disease: Disease also can be a factor in populations particularly those that are at or above the long-term carrying capacity of the area and in the absence of selective pressures like predation. Diseases spread faster when populations are dense, which is one of the reasons that feeding wildlife is generally a bad idea. [1,2,3]
Density Dependence: Density dependence is less a cause than and observation. There is a general tendency in populations that become dense to “self-edit” at some point and it is likely caused by any one of these factors or a complex combination of them. 
Secondary Plant Compounds: One of the most interesting areas of botany is looking at secondary plant compounds and how those plant produced chemicals often regulate the populations of animals that consume them. While we often think in terms of grazing critters determining vegetation there is a large body of evidence that in many cases it is the other way around. [1,2,3]
“Additive and compensatory are the two types of mortality that occur in mule deer populations. An increase in one cause of mortality or the introduction of a new type of mortality may or may not increase the total number of animals that die, depending on whether that mortality is additive or compensatory. If the increase or introduction of mortality increases the number of deer that die, the mortality is additive. If it is compensated for by reductions in other types of mortality, and therefore doesn’t change the total number of deer that die, then it is compensatory.” From Western Association of Fish and Wildlife Agencies website.
Additive versus Compensatory Predation: If a certain amount of prey species did not die each year through natural or artificial means, prey would quickly over populate their habitats with disastrous consequences. Because many wildlife agencies tend to want prey populations to exist at or near their carrying capacities this question of whether or not predation is compensatory or additive comes into play. One recent study looking at nearly 2800 radio collared elk in 45 areas, found that additive predation from all predators including wolves was less than 2%.
“Wolves are coursing predators that chase prey over long distances in open habitat and have a relatively low success rate, selecting substandard prey. The success rate on elk is 20 percent.” Notes on a talk by Dr. Dennis Murray University of Idaho on Western Hunter
Genetic Impacts: People shooting elk and wolves killing elk have different genetic implications. Hunters kill elk in the fall when the animals are fat after summer feeding. Wolf predation peaks in late winter and early spring when less biologically fit animals are at their most challenged [reference]. The former action has limited beneficial impact on the gene pool of elk because the selective pressures are only chance and size. In contrast, wolves chase animals and are most successful with those unable to escape or resist. While humans might not be able to differentiate between genetically robust individuals by sight it is believed that coursing predators such as wolves that chase their normally faster prey do so mechanically.
Pollution: Pollution from pesticides and herbicides are likely on the low side directly in Yellowstone but that is not true in the surrounding federal forests where the migratory elements of this herd frequent. Many people including citizen scientist Judy Hoy have been expressing concerns about some of these pollution effects and hopefully this is an area that will receive broader research attention in the future.
Actually the above is not really a menu per se, because all of these factors and more are all in play in the Northern Range and other locales where elk are declining and where they are increasing in the presence of wolves.
Thinking that wolves are completely driving the elk population decline in Yellowstone’s Northern elk herd is a lot like thinking that actor Elijah Wood is only three feet tall because he appeared to be that height in the Lord of the Rings trilogy. I would urge those who still adhere to the yard-tall thespian hypothesis to take a deep breath, employ some commonsense and dig a little deeper into the situation. I think that you will find that many wonderful things are going on and that wolves are only supporting players in this drama wholly undeserving of this deep hatred we observe and the wholesale slaughter heaped on this still recovering species.