{"id":95031,"date":"2025-10-22T20:51:32","date_gmt":"2025-10-22T20:51:32","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/95031\/"},"modified":"2025-10-22T20:51:32","modified_gmt":"2025-10-22T20:51:32","slug":"could-colorado-see-widespread-ecosystem-changes-from-wolf-restoration","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/95031\/","title":{"rendered":"Could Colorado see widespread ecosystem changes from wolf restoration?\u00a0"},"content":{"rendered":"

\t\t\t\t\t\"\"Gray wolves run across snow-covered terrain. The reintroduction of wolves could change the ecosystem in Colorado.
Colorado Parks and Wildlife (CPW)<\/p>\n

In Yellowstone National Park \u2014 where gray wolves<\/a> were reintroduced starting in 1995 \u2014 researchers have gone back and forth on whether the restoration of wolves has impacted the ecosystem.<\/p>\n

The idea is referred to as a \u201ctrophic cascade,\u201d where a change in an ecosystem\u2019s food chain \u2014 typically the removal or reintroduction of an apex predator like wolves \u2014 has a ripple effect on the other levels in the food chain and ecosystem. This can include changes to other species, plant life, the environment and more.\u00a0<\/p>\n

Brenna Cassidy, Colorado Parks and Wildlife\u2019s wolf monitoring and data coordinator, referred to whether wolves contribute to these ecosystem changes as \u201cone of the most hotly debated topics in wolf ecology.\u201d<\/p>\n

Cassidy spent nearly 15 years working with wolves across the West, including in Yellowstone National Park, prior to joining the state wildlife agency in October 2023.\u00a0<\/p>\n

\u201cThere are some researchers who point to wolves being the cause of that (trophic cascade) change,\u201d Cassidy said. \u201cThere are some researchers who don\u2019t.\u201d<\/p>\n

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The differing opinions are reflected in some of the latest studies on the topic in Yellowstone. In October, two studies published in the Forest Ecology and Management from researchers at Oregon State University have tied Yellowstone\u2019s restoration of wolves to a trophic cascade in the national park \u2014 one relating it to changes in aspen trees<\/a> and another to willow growth<\/a>. A paper published in the same journal, however, criticized the methodology<\/a>.\u00a0<\/p>\n

In the report on aspens, it claims that as wolves were reintroduced, elk browsing was reduced and resulted in the growth of aspen saplings for the first time in decades in northern Yellowstone.\u00a0<\/p>\n

\u201cThe reintroduction of large carnivores has initiated a recovery process that had been shut down for decades,\u201d Luke Painter, one of the study\u2019s lead authors, said in a news release<\/a>. \u201cWolf reintroduction is yielding long-term ecological changes contributing to increased biodiversity and habitat diversity.\u201d<\/p>\n

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The report also notes that the increase in bison numbers in other areas of the park may be constraining aspen growth.\u00a0<\/p>\n

The report on willows claimed a similar relationship, reporting that the impacts on elk grazing brought on by wolf reintroduction led to increased growth of willows over a 20-year study period. Painter, Robert Beschta and William Ripple were all lead authors on both studies.\u00a0<\/p>\n

The rebuttal does question whether the methodology is flawed and claims that evidence of a trophic cascade is\u00a0 \u201cweak.\u201d Specifically, it claims the research omits key factors like how hunting has reduced elk density, overestimates the height of willows and more.\u00a0<\/p>\n

\u201cFar from indicating a strong, system-wide cascade, the current evidence points to a more complex and constrained outcome \u2014 one that underscores the importance of analytical rigor and ecological context in evaluating the consequences of large carnivore recovery,\u201d the rebuttal states.\u00a0\u00a0<\/p>\n

The response mirrors and cites claims made in a 2024 study from Colorado State University researchers<\/a>. This study concluded that at the same time wolves were restored in Yellowstone, previously depleted mountain lion and grizzly bear populations began to see natural recovery, which helped stabilize the ecosystem. It claims that all the predator populations rebounding \u2014 as well as human hunting of elk \u2014 played a role in the elk population declines.<\/p>\n

It also reports that the rise of bison populations means that browsing of woody food sources, like willows, has not declined in proportion to the drop in elk. The study included research done by the authors in the park\u2019s northern range starting in 2001.\u00a0<\/p>\n

\u201cWhen you disturb ecosystems by changing the makeup of a food web, it can lead to lasting changes that are not quickly fixed,\u201d said Toms Hobbs, one of the report\u2019s lead authors and professor emeritus at Colorado State University, in a press release<\/a>. \u201cWe can\u2019t rule out the possibility that the ecosystem will be restored over the next 40 years as a result of the return of apex predators. All we can be sure of is what\u2019s observable now \u2014 the ecosystem has not responded dramatically to the restored food web.\u201d\u00a0<\/p>\n

The takeaway, Hobbs added, is not to lose these apex predators in the first place, as they lead to healthier ecosystems.\u00a0<\/p>\n

\"\"One of the original 10 wolves brought to Colorado as part of the reintroduction program is pictured shortly after its release.Colorado Parks and Wildlife\/Courtesy photo<\/p>\n

Will Colorado see ecosystem changes as a result of its wolf restoration?\u00a0<\/p>\n

As researchers debate whether the reintroduction of wolves has led to strong trophic cascades, a similar debate could sprout in Colorado as it wraps up the second year in its wolf restoration.\u00a0<\/p>\n

In the 2024 report, Hobbs and his co-author, David Cooper, a research scientist emeritus at Colorado State University, noted that wolves may not cause immediate ecosystem improvements, but would still have positive impacts. The authors also acknowledged differences in the management of elk populations between Yellowstone and Colorado \u2014 namely that Colorado has not seen negative impacts from excessive elk grazing as Yellowstone had.\u00a0<\/p>\n

Cooper, in a press release, said \u201cwolves are important components of ecosystems.\u201d\u00a0<\/p>\n

\u201cThey will have some ecosystem benefits by reducing some large herbivore populations,\u201d Cooper added. \u201cOver the next hundred years, they\u2019ll have a greater role in regulating some of the ecological processes that we\u2019ve been studying.\u201d<\/p>\n

When asked about whether Colorado could see these types of impacts, Cassidy noted that, in general, trophic cascades are \u201cvery hard to detect through research\u201d because of all the moving pieces in any ecosystem. This includes all the animal species, plant species and climate impacts like precipitation, temperature and soil health.\u00a0<\/p>\n

\u201cIt\u2019s so complex that it\u2019s really hard to detect not only just a trophic cascade, but why that\u2019s happening,\u201d Cassidy said. \u201cIt\u2019s a hard thing to detect on a scale like Yellowstone. It\u2019s even harder to detect something that is on a statewide scale.\u201d<\/p>\n

In Colorado, considerations would have to be made around hunting, development, water use and more.\u00a0<\/p>\n

Regardless, as Colorado is still so early in its wolf reintroduction \u2014\u00a0with at least one more release of 10 to 15 wolves planned for this winter \u2014 it will be a long time before this can even be looked at.<\/p>\n

\u201cIf there is some sort of trophic cascade or effects on the ecological community in Colorado, it\u2019s not something that can be pointed to right away and it will be very, very hard to detect something going on,\u201d Cassidy said. \u201cThere are some researchers who are very aware of all those challenges and working to come up with research programs that will be monitoring this, but it is not something that we should expect to be able to detect as scientists for a while.\u201d\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"Gray wolves run across snow-covered terrain. The reintroduction of wolves could change the ecosystem in Colorado.Colorado Parks and…\n","protected":false},"author":2,"featured_media":95032,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[111,139,69,147,406],"class_list":["post-95031","post","type-post","status-publish","format-standard","has-post-thumbnail","category-wildlife","tag-new-zealand","tag-newzealand","tag-nz","tag-science","tag-wildlife"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/95031","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=95031"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/95031\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/95032"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=95031"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=95031"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=95031"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}