Variation in sage-grouse habitat quality metrics across a gradient of feral horse use

Hennig, Jacob D.; Beck, Jeffrey L.; Duchardt, Courtney J.; Scasta, John Derek

doi:10.1016/j.jaridenv.2021.104550

Cited by 7 publications

(6 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The western portion of the study area was predicted to be highly used by horses and sage-grouse during the breeding season. Recent research documented decreased grass height and increased bare ground with greater horse use in the Adobe Town HMA (Hennig et al 2021a), which could negatively influence recruitment (nest and brood survival) in this sage-grouse population. Further, some of the most well-attended leks fell within areas of high horse use, which may disrupt grouse breeding activity (Muñoz et al 2021).…”

Section: Discussionmentioning

confidence: 98%

“…There is sparse but emergent information concerning the influence feral horses have on sage-grouse (Muñoz et al 2021, Coates et al 2021a, Hennig et al 2021a, and multiple sources have listed horses as a potential threat to sage-grouse populations (Beever and Aldridge 2011, Southwest (Muñoz et al 2021) but are mainly thought to indirectly affect them through habitat alteration.…”

mentioning

confidence: 99%

“…Potential competition between cattle and feral horses has been a concern because of strong diet overlap and potential for horses to decrease rangeland quality (Beever et al 2008, Scasta et al 2016). Feral horse grazing can decrease vegetation biomass, increase soil compaction, increase proportion of bare ground, and facilitate the spread of invasive species (Beever et al 2008, Davies et al 2014, King et al 2019, Hennig et al 2021 a ). The direct and indirect effects that feral horses may have on native fauna is less understood.…”

mentioning

confidence: 99%

“…There is sparse but emergent information concerning the influence feral horses have on sage‐grouse (Muñoz et al 2021, Coates et al 2021 a , Hennig et al 2021 a ), and multiple sources have listed horses as a potential threat to sage‐grouse populations (Beever and Aldridge 2011, Southwest Wyoming Local Sage‐grouse Working Group 2013, U.S. Fish and Wildlife Service 2013, South Central Sage‐grouse Local Working Group 2014).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Habitat selection and space use overlap between feral horses, pronghorn, and greater sage‐grouse in cold arid steppe

et al. 2022

Self Cite

View full text Add to dashboard Cite

Populations of feral horses (Equus ferus caballus) in the western United States have increased during the past decade, consequently affecting co-occurring wildlife habitat. Feral horses may influence 2 native wildlife species, greater sagegrouse (Centrocercus urophasianus; sage-grouse) and pronghorn (Antilocapra americana) through mechanisms of habitat alteration and competition. Wyoming, USA, contains the largest populations of pronghorn and sage-grouse of any state and also has the highest degree of range overlap between feral horses and these species. Consequently, the effects that horses may have on pronghorn and sage-grouse populations in Wyoming have implications at local, state, and populationwide levels. Managers need information concerning habitat selection and space use overlap among these species to develop appropriate management strategies; yet this information is absent for most feral horse management areas. To address this knowledge need, we attached global positioning system (GPS) transmitters to horses, pronghorn, and sagegrouse within the greater Bureau of Land Management-Adobe Town Herd Management Area in southern Wyoming and northern Colorado, USA, between 2017 and 2021 to evaluate habitat selection and space use of all species during 3 biologically relevant seasons: spring (Apr-Jun; sage-grouse breeding, nesting, and early-brood rearing; pronghorn late gestation and early parturition), summer (Jul-Oct; sage-grouse summer and late-brood rearing; pronghorn late parturition and

show abstract

Section: Discussionmentioning

confidence: 98%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Habitat selection and space use overlap between feral horses, pronghorn, and greater sage‐grouse in cold arid steppe

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…In 2013, the National Research Council advised more research was needed on several topics related to horse and burro management, including increased information on basic horse and burro ecology [19]. Since then, many studies have added to the body of knowledge on free-roaming equid ecology in North America [e.g., 10,[20][21][22][23], diet [24,25], behavior [26,27], and interactions with native wildlife [e.g., [28][29][30][31]]. Yet only a few studies have applied global positioning system (GPS) collar technology in studies of free-roaming equids in North America [10,20,32,33].…”

Section: Introductionmentioning

confidence: 99%

Effects of telemetry collars on two free-roaming feral equid species

Schoenecker,

King,

Hennig

et al. 2024

PLoS ONE

Self Cite

View full text Add to dashboard Cite

There are two species of free-roaming feral equids in North America: horses (Equus caballus) and donkeys or “burros” (E. asinus). Both species were introduced as domestic animals to North America in the early 1500s and currently inhabit rangelands across the western United States, Canada, and all continents except Antarctica. Despite their global distribution, little is known about their fine scale spatial ecology. Contemporary research tools to assess space use include global positioning system (GPS) tracking collars, but older models were problematic due to stiff collar belting causing poor fit. We tested modern designs of GPS collars on n = 105 horses and n = 60 burros for 4 years in five populations (3 horse, 2 burro) across the western United States, to assess whether collars posed welfare risks to horses or burros. We found no difference in survival of collared versus uncollared mares and jennies, and no difference in survival of their foals. In 4036 of 4307 observations for horses (93.7%) and 2115 of 2258 observations for burros (93.6%), collars were observed symmetrical, maintaining proper fit on the neck. Fur effects from collars (sweaty neck, indented fur, broken fur) were seen in 3% of horse observations and 25% of burro observations. Superficial effects (chafes and marks on skin surface) were seen in 2% of horse observations and 11% of burro observations; no severe effects from collars were seen. Body condition was not affected by collars; mean body condition of collared horses was 4.70 ± 0.54 (mean ± s.d) and 4.71 ± 0.65 for collared burros. Behavior results indicated minimal effects; collared horses stood slightly more than uncollared, and collared burros stood and foraged more in one population, but not in the other. For 6.3% of observations of horses and 6.4% of observations of burros, we found an effect of time wearing a collar on the cumulative sum of fur effects which increased over time (burros: rs = 0.87, P = <0.0001; horses: rs = 0.31, P = 0.002). Burros also showed an increase over time in the number of superficial effects, but horses did not. Collars occasionally moved into the wrong position, shifting forward over the ears; we observed this on 19 horses and 1 burro. Of those, most collars went over the ears in summer (n = 12). All collars were equipped with a remote release mechanism as well as a timed-release mechanism for redundancy, thus removed when observed in wrong position to avoid rubbing or discomfort. Our finding of no consequential physical effects in 98% of horse observations, and 89% of burro observations suggests the consequences of collars on free-roaming equid welfare and survival is biologically insignificant, although collars should be monitored regularly and continue to be equipped with a remote release mechanism to remove a collar if needed. With frequent welfare-driven, visual monitoring, collaring of free-roaming equids can be a safe and useful tool to increase our understanding of their spatial ecology, demography, habitat use, behavior, and interactions with other wildlife.

show abstract

Free‐roaming horses exceeding appropriate management levels affect multiple vital rates in greater sage‐grouse

Beck,

Milligan,

Smith

et al. 2024

J Wildl Manag

View full text Add to dashboard Cite

Since the passage of the Wild Free‐Roaming Horses and Burros Act of 1971, federal agencies have been responsible for managing free‐roaming equids in the United States. Over the last 20 years, management has been hampered by direct opposition from advocacy groups, budget limitations, and a decline in the public's willingness to adopt free‐roaming horses (Equus caballus). As a result, free‐roaming equid numbers have increased to >3 times the targeted goal of 26,785 (horses and burros [E. asinus] combined), the cumulative sum of the appropriate management levels (AML) for all 177 designated herd management areas (HMA) managed by the Bureau of Land Management. This increase is one of the causes of greater sage‐grouse (Centrocercus urophasianus) population declines, owing to habitat alteration from free‐roaming equids exacerbated by ongoing drought. To evaluate potential demographic mechanisms influencing these declines, we compiled survival data from 4 studies in central Wyoming, USA, including 995 adult female (first‐year breeders or older) sage‐grouse during the breeding season, 1,075 nests, 372 broods, and 136 juveniles (i.e., overwinter survival for fledged young), from 2008–2022. During this period, we also obtained population information for free‐roaming horses from 9 HMAs used by individual grouse in our sample. Population estimates of free‐roaming horses for these HMAs ranged from 59% to 7 times of the maximum appropriate management level (AMLmax). Sage‐grouse monitored outside of HMAs represented control populations and, because we assumed they were not exposed to populations of free‐roaming horses, we set values of AMLmax to zero for all grouse located outside of HMAs. To evaluate whether free‐roaming horses were negatively affecting sage‐grouse, we modeled daily survival of breeding age females, nest, broods, and juveniles. There was strong or moderate evidence that overabundant free‐roaming horses negatively affected nest, brood, and juvenile survival. When horse abundance increased from AMLmax to 3 times AMLmax, survival was reduced 8.1%, 18.3%, 18.2%, and 18.2% for nests, early broods (≤20 days after hatch), late broods (>20 days to 35 days after hatch), and juveniles, respectively. These results indicate increasing free‐roaming horse numbers affected vital rates for important life stages of sage‐grouse, and that maintaining free‐roaming horse numbers below AMLmax would reduce negative effects to sage‐grouse populations.

show abstract

Variation in sage-grouse habitat quality metrics across a gradient of feral horse use

Cited by 7 publications

References 61 publications

Habitat selection and space use overlap between feral horses, pronghorn, and greater sage‐grouse in cold arid steppe

Habitat selection and space use overlap between feral horses, pronghorn, and greater sage‐grouse in cold arid steppe

Effects of telemetry collars on two free-roaming feral equid species

Free‐roaming horses exceeding appropriate management levels affect multiple vital rates in greater sage‐grouse

Contact Info

Product

Resources

About