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KEY FINDINGS OF THE 2013 NATIONAL ACADEMY OF SCIENCES REPORT,USING SCIENCE TO IMPROVE THE BLM WILD HORSE AND BURRO PROGRAM:

A WAY FORWARD

BLMs Business as Usual Unproductive

Continuation of business as usual practices will be expensive and unproductivefor BLM and the public it serves. p. 14

BLM AMLs Not Transparent, Equitable or Based on Science

The committee could not identify a science-based rationaleused by BLM toallocate forage and habitat resources to various uses within the constraints ofprotecting rangeland health and listed species and given the multiple-use

mandate. p. 303

How Appropriate Management Levels (AMLs) are established, monitored,and adjusted is not transparent to stakeholders, supported by scientificinformation, or amenable to adaptationwith new information andenvironmental and social change. Standards for transparency, quality and equityare needed in establishing these levels, monitoring them and adjusting them. p.12

AMLs are a focal point of controversy between BLM and the public. It is thereforenecessary to develop and maintain standards for transparency, quality, and

equity in AML establishment, adjustment, and monitoring. p. 12

BLM Roundups Increase Horse Populations

Management practices are facilitating high rates of populationgrowth.!Thus, population growth rate could be increased by removals throughcompensatory population growth from decreased competition for forage. As aresult, the number of animals processed through holding facilities is probablyincreased by management. p. 5-6

Removals are likely to keep the population at a size that maximizes

population growth rate, which in turn maximizes the number of animals thatmust be removed through holding facilities. P. 94

BLM may also need to assess whether the AMLs set for burros can sustain agenetically healthy total population. p. 303-304

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BLM has Tools to Address challenges

Tools [including PZP fertility control] already exist for BLM to address manychallenges. p. 13 (P. 303 confirms that BLM is not using PZP in a manner that

will impact population growth.)

In the short term, more intensive management of free-ranging horses and burroswould be expensive. However, addressing the problem immediately with along-term view is probably a more affordable option than continuing toremove horses to long-term holding facilities. p. 13-14

BLM Under Utilizes Fertility Control

According to BLMs presentation to the committee, the agency treated anaverage of 500 mares a year with the porcine zona pellucida (PZP) vaccine from

2004 to 2010; just over 1,000 were treated in 2011 (Bolstad, 2011).Contracepting 500-1,000 mares a year with a 2-year vaccine will notsubstantially lower the rate of growth of a population of over 30,000 horses.p. 303 Note: in 2015, BLM vaccinated 469 mares with PZP.

Ovariectomy and Gelding Not Recommended

The possibility that ovariectomy may be followed by prolonged bleeding orperitoneal infection makes it inadvisable for field application. p. 148149

A potential disadvantage of both surgical and chemical castration is loss of

testosterone and consequent reduction in or complete loss of male-typebehaviors necessary for maintenance of social organization, band integrity,and expression of a natural behavior repertoire.p. 142