Guest Blog: A Look at the Black Mountain Burro Roundup
By Laurie Ford, guest blog
(Aug 4, 2022) As roundup season escalates, we must not forget those that occurred over the past few months, especially the roundup of Arizona’s Black Mountain burros. These burros are descendants of those used by miners and prospectors during the 1860s and represent one of the last large, genetically healthy burro herds.
While the roundup may have ended, it marks the beginning of more trauma and a long, sometimes life-threatening journey for these burros. Initially, they are placed in temporary holding where they form new bonds, only to be separated again as they are moved between facilities until adoption. Unfortunately, there are no designated long-term facilities for these burros, and they will never have the chance to “retain their wild status” in an off-range pasture as claimed by the BLM.
Not having the chance to observe the roundup, I decided to visit all 1,093 of the Black Mountain burros at the Arizona Florence Holding Facility.
Watching so many burros, once wild and free, now confined, was heartbreaking. Small groups circled the pens, trying to mimic their nomadic lifestyle, while others huddled with newfound friends or gathered along the fence, curiosity overcoming fear.
The burros were beautiful, in good shape with shiny coats. They displayed a variety of colors and markings, with grays being most prominent, featuring light muzzles, dark dorsal stripes, and zebra-like leg stripes. These characteristics reflect their North African origins, where the African wild donkey has been critically endangered since 1996.
There were also many foals. Of the 541 jennies and 104 foals rounded up, many jennies likely aborted, gave birth in holding, or will foal in the coming weeks or months.
Many pregnant jennies will be adopted by people with limited knowledge of wild burros. When a foal is born post-adoption, it is not recorded in the BLM database, leaving adopters free to do as they wish. These foals disappear from the system, unaccounted for.
Soon, the Florence Facility pens will be emptied, and the burros will be gone. However, this scenario will repeat due to the November 2021 aerial survey calling for further roundups.
Using the current Standard Operating Procedures for Wild Horse and Burro Double-Observer Aerial Surveys (2020), the on-range population estimate almost doubled to 2,976, despite 485 burros being removed, from an earlier estimate of 1,531. Without this adjustment, the latest roundup would have brought the Herd Management Area (HMA) close to the Appropriate Management Level (AML), but instead, it ensures continued roundups.
The BLM believes burro population estimates are low due to undetected burros during aerial surveys. The USGS study developed new estimation techniques to account for these missed burros.
When observing small bands from the air, it can be problematic. Each band is likely observed by one person who must quickly record details. Observers try to photograph large groups for documentation, but opportunities are limited. Even without data comparison, this information is used to project population numbers for BLM guidelines.
Future population growth is determined using an average expected annual growth rate, assuming past rates apply. This often overlooks factors like climate, population density, resource conditions, and fertility control, impacting numbers annually.
Variables like herd size, vegetation cover, and observer experience are now significant in detection and abundance estimations. However, they have only been assessed for a few populations. The USGS suggests using larger sample sizes from additional areas to refine understanding of key covariates.
I’m curious where they will find larger sample sizes as the BLM reduces the nationwide population to 2,900. The Black Mountain burros exemplify this issue.
USGS recommended post-gather aerial surveys to verify count methods and analyze trends over time. The BLM has not announced plans for such surveys in the Black Mountain HMA, where seven years passed between the 2014 and 2021 surveys.
The BLM is not required to follow USGS guidelines for estimating and reporting annual HMA herd abundances, leading to guesswork and judgment calls. Increased use of radio collars was suggested but is unlikely due to cost and potential technical failure.
According to the BLM, after the latest roundup, nearly 2,000 wild burros remain on the Black Mountain HMA. An estimated 1,522 need removal to reach an AML of 478. If the annual growth rate formula is applied in FY2023, both on-range population and roundup numbers will increase.
No wonder the roundups never seem to end.