Endangered species protections in the United States were first introduced over 120 years ago when concerns about the disappearance of passenger pigeons motivated Congress to create the “Lacey Act of 1900”.
Sixty-six years later, Congress passed the “Endangered Species Preservation Act”, a law that underwent several revisions before being scrapped in favor of what we now call, the “Endangered Species Act” (ESA).
The ESA has also undergone revisions since it was passed in 1973. Like previous laws intended to prevent animal extinctions, the ESA is imperfect and open to legal wrangling and judicial interpretation. Continuous litigation over its intent, word smithing, and vagaries of implementation, have created intense controversy and ongoing conflict.
The problem with the ESA is that there are multiple words, phrases, and definitions that are vague and non-discerning. Some of the concepts written into the ESA are not supported by research. Disputes over taxonomical classifications and ambiguous wording continue to thwart the implementation of common sense science based policies.
One such example is the debate over what constitutes “a significant portion” of a species range. Estimates of a species historic range compared to its current range are not supposed to influence whether or not a particular species warrants protection. Yet it does, as exemplified by how both grizzly bears and gray wolves continue to be protected based on their historic ranges and political boundaries rather than on the species biological health, their global range, and their actual population. (See my 2017 blog article, “What’s Wrong with The ESA?”)
Under the ESA, the U.S. Fish and Wildlife Service has a mandate to use the best available scientific or commercial data in making a ruling as to whether a specific taxon merits listing for legal protections. Most folks learned in high school biology that a species is defined as a group of animals that can interbreed with others of its kind and produce viable offspring. The species level has always been the basic fundamental category for taxonomic classification.
However, the writers of the ESA chose to muddy the waters by creating something called, “Distinct Population Segments”. This newly created taxonomic category further divides species into arbitrary sub-groups based on minor morphological variations exhibited by isolated regional populations.
In the case of the gray wolf, this has led to the protection of the “Red” wolf on the east coast, the “Mexican” gray wolf in the American southwest, and the “Rocky Mountain” gray wolf in our northern states. These so-called DPS categorizations were created despite research showing extensive hybridization among the subject populations, including genetic mixing with coyotes and dogs.
The assignment of a Distinct Population Segment label is a wholly arbitrary categorization because it embraces some of the morphological differences among wolves while ignoring a similar level of differentiation identified in dozens of regionally isolated wolf sub-groups.
Historically speaking, multiple varieties of wolves were noted by the Lewis and Clark expedition as they journeyed west. According to Lewis’s observations, northwest wolves varied in appearance and were somewhat smaller than the wolves he was familiar with on the east coast. In his journal, Captain Lewis noted that wolves were observed by Corps members on 59 different days. Although some of these wolves may have looked a little different from region to region, one thing remained constant. All the wolves which the Corps of Discovery encountered exhibited the same wolf-like behavior, including several instances of aggressive attacks on Corps members and their livestock. This behavior prompted members of the expedition to shoot some 36 wolves over their 28 month journey.
The Canadian sourced wolves that were translocated in 1995 into Wyoming and Idaho were larger than the wolves described as inhabiting the region by Lewis and Clark in 1804-5. Ironically, these larger Canadian wolves are now called “Rocky Mountain” wolves and have been given their own DPS by agency bureaucrats. This does not mean that these wolves are a different species than the wolves that may have been present in the region prior to 1995. No, on the contrary, regardless of their geographical distribution or variations in size or coloration, all wolves, throughout all of recorded history, in all regions of the world, are the same species.
Wilson and Reeders authoritative volume on taxonomy “Mammals of the World” lists one species of wolf and multiple sub-species.
SPECIES Canis lupus
SUBSPECIES Canis lupus lupus
SUBSPECIES Canis lupus albus
SUBSPECIES Canis lupus alces
SUBSPECIES Canis lupus arabs
SUBSPECIES Canis lupus arctos
SUBSPECIES Canis lupus baileyi
SUBSPECIES Canis lupus beothucus
SUBSPECIES Canis lupus bernardi
SUBSPECIES Canis lupus campestris
SUBSPECIES Canis lupus chanco
SUBSPECIES Canis lupus columbianus
SUBSPECIES Canis lupus crassodon
SUBSPECIES Canis lupus dingo
SUBSPECIES Canis lupus familiaris
SUBSPECIES Canis lupus floridanus
SUBSPECIES Canis lupus fuscus
SUBSPECIES Canis lupus gregoryi
SUBSPECIES Canis lupus griseoalbus
SUBSPECIES Canis lupus hattai
SUBSPECIES Canis lupus hodophilax
SUBSPECIES Canis lupus hudsonicus
SUBSPECIES Canis lupus irremotus
SUBSPECIES Canis lupus labradorius
SUBSPECIES Canis lupus ligoni
SUBSPECIES Canis lupus lycaon
SUBSPECIES Canis lupus mackenzii
SUBSPECIES Canis lupus manningi
SUBSPECIES Canis lupus mogollonensis
SUBSPECIES Canis lupus monstrabilis
SUBSPECIES Canis lupus nubilus
SUBSPECIES Canis lupus occidentalis
SUBSPECIES Canis lupus orion
SUBSPECIES Canis lupus pallipes
SUBSPECIES Canis lupus pambasileus
SUBSPECIES Canis lupus rufus
SUBSPECIES Canis lupus tundrarum
SUBSPECIES Canis lupus youngi
All of the animals listed above can, and will, interbreed if given the opportunity, and will produce fertile offspring as verified by direct observation and confirmed by genetic sampling. This fact alone is sufficient to refute the idea that each of these animals is a different kind, or that any one variety of wolf should receive special consideration as a “Distinct Population Segment”. It would be like dividing human beings into different sub-species based on body size, leg length, hair color, or skin pigmentation.
It is ironic that Colorado voters mandated wolf introduction and brought Canadian sourced wolves into the state. These wolves now pose a direct threat to the USFW’s carefully planned “Mexican” wolf DPS in Arizona and New Mexico. It is inevitable that these two “kinds” of wolves will begin interbreeding as both wolf populations are expanding and will soon overlap each other’s ranges.
The Endangered Species Act should be revised based on the inability to define an endangered animal without using lines drawn on a map or clarifying the common scientific meaning of the word “species”. That could be a task that is easier said than done because even taxonomists and evolutionary biologists cannot seem to agree on a definition of the word “species”. The ESA goes even further off the rails when implementing protections based on sub-divisions that go beyond the species level when there is no rational scientific justification for doing so.
To conclude this little rant, let me just say that research into wolf genetics has proven that there is no such thing as a “pure” wolf. Gene sampling has confirmed that extensive hybridization of the wolf genome has occurred throughout history in all regions of the world. This means that minor morphological differences are attributable to inbreeding resulting from genetic isolation as well as differences in diet and other environmental factors.
To put this all into perspective, Nature Magazine recently published research supporting the linked ancestry of wolves and dogs, which are both classified as Canis lupus. Here’s a quote from the Nature article: “We analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today.”
Yeah, you read that right, “lower than they are today”. That means varietal differentiation in the wolf genome was almost non-existent in the past, but has increased significantly over the last few centuries or so. This relatively recent increase in differentiation is obviously a direct result of man’s impact on wolf range, distribution, and habitat fragmentation. Disruption in connectivity caused by human development and activity has resulted in decreased mixing between isolated regional wolf populations. Isolation leads to increased inbreeding, which results in minor regional variations among wolves. That said, gray wolves continue to enjoy the widest circum-polar range of any large terrestrial predator on the planet. They are not, and have never been, an endangered species
The truth of the matter is this: If it looks like a wolf, acts like a wolf, then you can be rest assured, it’s a wolf.
Sources for this article include:
https://www.press.jhu.edu/books/title/8864/mammal-species-world
https://www.nature.com/articles/s41586-022-04824-9
https://en.wikipedia.org/wiki/Lacey_Act_of_1900
https://www.fws.gov/esa50/our-history/pre-1973
https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2022.971280/full
omots page 
Steven,
You’re not wrong about the mess. The ESA is a legal quagmire, “significant portion of range” is a judicial piñata, and DPS can feel like taxonomists playing God with a Sharpie. You nailed the history—Lacey Act, 1966 precursor, 1973 overhaul—and the science: Canis lupus is one interfertile species, ancient wolves were genetic soup (Nature 2022), and your Lewis & Clark journal pull is spot-on (59 sightings, 36 shot). Global gray wolves are thriving; no argument.
But here’s where you overshoot:
You want science-based policy? Great. Mandate genomic thresholds for DPS (e.g., heterozygosity <70% of conspecifics) and ecological irreplaceability metrics. But scrapping subdivisions because wolves interbreed is like defunding cancer research because all tumors are “just cells.”
You’re right to howl. Just aim the bite at the bureaucracy, not the biodiversity.
Thank you for taking the time to comment. Your points are well organized, specific, and clearly show the other side of the argument quite well. However, I strongly disagree with most of them.
Let’s me address your first point, and maybe interject a few thoughts about your other points as well.
First, you claim that “Conservation isn’t global headcount. The ESA guards American ecosystems.”
I don’t disagree. The ESA is an American law that only applies to U.S. jurisdiction The statement actually proves my point which is that political boundaries are not biologically sound determiners of a species biological health or risk of extinction. However, we are confined by political realities and cannot make laws that govern the entire planet (at least not yet anyway).
Let’s look at this from a state perspective. In Washington state, grizzly bears are considered to be “endangered within the state” and have been under full legal protection in WA for some 40 years. That is a far more accurate statement than saying, “grizzly bears are an endangered species”.
Obviously, we must come to some sort of agreement on a clear definition of what the word “endangered” means as it relates to the word “extinction”. The ambiguity of words in the ESA, and certain political realities under the U.S. Constitution, is why boundary lines drawn on maps have become paramount in creating government policy as it relates to the ESA. The actual biological status of a species is being ignored because it transcends political boundaries and undermines certain political agendas and narratives.
The correct terminology that should be used to describe the biological status of grizzly bears and gray wolves in the U.S., is that both populations had at one time in the not too distant past, been subjected to “extirpation” in various U.S. states. In other words, these animals were removed from a portion of their range to make room for human development, settlement, agriculture, or to address safety concerns, etc.
Extirpation did no harm to the ability of either species to thrive. Neither the brown bear, or the gray wolf, has ever been in any danger of extinction. The definition of the word “extinction” refers to a species that no longer exists anywhere on the face of the earth. Extinction is not a local or regional concept, it is a global concept. It carries a far different connotation and meaning than the word, “extirpation”.
One should not try to change the meaning of words, or re-interpret words, to fit a specific narrative for personal or political gain. Re-establishing an animal population that no longer inhabits a specific region that it once historically did should be called what it actually is, REWILDING, which is a wholly different concept than “conservation”.
At the risk of repeating myself, There is no such thing as “regional extinction”. Extinction is the final and irretrievable disappearance of a species from the face of the earth.
Attempts to bring back the wooly mammoth, or the giant auroch, even dinosaurs, are based on concepts supporting REWILDING, which is defined as returning human impacted environments to what they were like before humanity impacted them by using large predators to accomplish the task. In other words, we do not need wolves or grizzly bears everywhere they once lived simply because somebody thinks it is a good idea. The proliferation of either species is merely a tool to accomplish a goal.
To sum up my point….a net reduction in a species range is not a primary indicator of the species health, but is merely one factor among many that should be considered when making a determination under the requirements of the ESA.
If you want to bring bears and/or wolves back into areas where they were once extirpated from, just say so. That is called REWILDING, and it has nothing to do with preventing the extinction of the species. This is why I am very much against a National wolf recovery plan. The very concept is patently anti-human and would be an environmental and cultural disaster for the citizens of the United States.
Whew! I’ve gone way longer than I should have. My apologies. Some of your other points may require even more ink. We’ll see. Thanks for the challenge.
Steve
Steven,
Thanks for the thoughtful pushback—glad the structure landed. I’ll keep this tight and speak to your core: “extinction vs. extirpation,” “rewilding vs. conservation,” and why political boundaries do matter under the ESA. 1. Extinction Is Global. Extirpation Is Real—and the ESA’s Job.
You’re 100% right:
No argument. Grizzlies and wolves were extirpated from most of the lower 48. They were never at global risk.
But here’s the legal and ecological reality: The ESA was written to prevent both.
That “significant portion” clause? Congress put it there on purpose. They knew passenger pigeons weren’t globally gone when the Lacey Act passed—they were gone from the East. The ESA’s framers (Nixon signed it) wanted to stop regional collapse before it became global.
You say: “A net reduction in range is not a primary indicator of species health.” True—but it is a primary indicator of ecosystem health. Wolves in Yellowstone don’t just “exist.” They:
That’s not “rewilding for fun.” That’s restoring trophic function in a system we broke. 2. “Rewilding” vs. “Conservation”? False Dichotomy.
You define rewilding as:
Fair. But the ESA is rewilding—by statute.
Bringing wolves back to Idaho or Colorado is recovery under the ESA. Calling it “anti-human” ignores:
You fear a “national wolf recovery plan” as cultural disaster. There isn’t one. Recovery is region-by-region, delisting happens when goals are met (e.g., Northern Rockies delisted 2011, relisted 2022 on legal technicality, now delisted again in 2025). The ESA bends—slowly, painfully—but it bends. 3. Political Boundaries Are Biological Realities
You say: “Political boundaries are not biologically sound.” Correct. But they’re human realities.
The ESA operates in a federal system:
Washington listing grizzlies as “endangered within the state”? That’s state law, not ESA. Federal ESA lists the Lower 48 population as threatened (not endangered), with recovery zones (e.g., North Cascades, Bitterroot).
You want science over politics? So do I. But science says:
The ESA’s “significant portion” rule isn’t narrative—it’s risk assessment. A grizzly population in WA with <50 animals is functionally extinct locally, even if 1,000 roam Alberta. One disease, one bad winter, one poacher—gone. That’s not extinction, but it’s biological failure. 4. Let’s Fix the Words—Not Burn the Law
You want clarity:
I’m with you. But the fix isn’t scrapping DPS or “significant portion.” It’s statutory precision:
Final Word
You’re not wrong to rage at the ESA’s fuzziness. But wolves in Colorado aren’t there to spite ranchers—they’re there because voters demanded it (Prop 114 passed 51–49%). The ESA didn’t force it. Democracy did.
You want science over politics? Then let science set the targets, and politics pay the bill.
Keep howling. Just aim the bite at the process, not the predators.
Wow, you’ve just about hit all of the talking points put forward by the pro-wolf side. Please review the 30 or so articles I have written which address each of your points in greater detail, including the fallacy of “trophic cascades”, which even wolf advocate David Mech has recanted.
I recently addressed this very topic (once again) in a Facebook post claiming wolves have had a positive impact on the YNP ecosystem. Here’s what I wrote:
Considering that the annual protein biomass consumption rate for a single wolf is measured in tonnage rather than pounds, (or the equivalent of 20 to 24 elk per wolf annually), it is no wonder that the ungulate population has plummeted in Yellowstone park. But hey, as YNP biologist Doug Smith and his cronies consistently like to point out, at least there are more shrubs growing along stream banks. But what they don’t tell you is that there are also more ravens, crows, black flies, and carrion beetles. And don’t forget about the billions of hydatid eggs and cysts that are now scattered across the landscape infecting the remaining wildlife thanks to wolves. Yes, wolves do change things. But to say that such changes are “good” or for the better, is a value judgment that is supported by the careful selection of facts painting wolves as the saviors of nature while omitting other observable facts that may not be as favorable to the pro-wolf agenda.
And as far as aspen regeneration goes, that has been happening in YNP since the huge fires of 1988, which burned 36% of the park. Those of us who have fought fires in the region were taught to seek out aspen groves when planning escape routes from super hot fires burning in the timber. Aspen groves are notoriously resistant to fire as they consist of thousands of interconnected plants sucking up millions of gallons of water from the ground. Fire that has opened up the forest canopy by burning off dense stands of diseased timber has done more for aspen groves than wolves ever could.
Well if you disagree with what I have stated above, I’m sure you will find all of my other posts on REWILDING equally challenging.