Nevada Bighorn Sheep Herd Management: what, when, and why for continued success

Bloody Run Hills CBS Reintroduction Jan 2019

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Nevada's Bighorn Sheep Population Estimates & Intrastate Transplants 1965- 2019

Bighorn Population Bighorn Transplanted

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

Mormon Mtns 1980/1994 440 320 120 40 27 6

Sheep Range 1986 850 225 625 ?? 30 14

Badlands 1999 100 33 67 46 33 12

Specter Range 2002 130 130 0 38 21 11

Santa Rosa Range 2003 320 150 170 58 29 6

Hiko Range 2004 100 75 25 40 30 6

Mt Moriah 2007 95 90 5 67 32 6

Egan Range 2001 60 15 45 38 ? 14

Ruby Mountains 2009 160 40 120 50 60 5

East Humboldt Range 2009 180 20 160 50 30 6

Pilot Range/Leppy Hills 2010 115 45 70 45 23 9

Pancake Range 2011 320 220 100 44 23 5

Snowstorm Mtns 2011 125 30 95 44 25 5

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

Mormon Mtns 1980/1994 440 320 120 40 27 6

Sheep Range 1986 850 225 625 ?? 30 14

Badlands 1999 100 33 67 46 33 12

Specter Range 2002 130 130 0 38 21 11

Santa Rosa Range 2003 320 150 170 58 29 6

Hiko Range 2004 100 75 25 40 30 6

Mt Moriah 2007 95 90 5 67 32 6

Egan Range 2001 60 15 45 38 ? 14

Ruby Mountains 2009 160 40 120 50 60 5

East Humboldt Range 2009 180 20 160 50 30 6

Pilot Range/Leppy Hills 2010 115 45 70 45 23 9

Pancake Range 2011 320 220 100 44 23 5

Snowstorm Mtns 2011 125 30 95 44 25 5

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

Mormon Mtns 1980/1994 440 320 120 40 27 6

Sheep Range 1986 850 225 625 ?? 30 14

Badlands 1999 100 33 67 46 33 12

Specter Range 2002 130 130 0 38 21 11

Santa Rosa Range 2003 320 150 170 58 29 6

Hiko Range 2004 100 75 25 40 30 6

Mt Moriah 2007 95 90 5 67 32 6

Egan Range 2001 60 15 45 38 ? 14

Ruby Mountains 2009 160 40 120 50 60 5

East Humboldt Range 2009 180 20 160 50 30 6

Pilot Range/Leppy Hills 2010 115 45 70 45 23 9

Pancake Range 2011 320 220 100 44 23 5

Snowstorm Mtns 2011 125 30 95 44 25 5

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s - continued

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

White Pine Range/Duckwater Hills 2011 180 100 80 50 18 6

McCullough Range 2012 450 210 240 42 14 5

Spring Mountains 2013 300 140 160 38 18 3

Last Chance Range 2013 180 150 30 37 24 2

Eldorado Mountains 2013 200 80 120 33 18 5

River Mtns 2013 270 200 70 41 17 5

Stonewall Mtn/NTTR 2014 330 175 155 41 8 4

Montana Mtns 2015 90 0 90 50 N/A --

Bare Mountain 2015 250 160 90 40 10 3

Newberry Mtns 2015 120 50 70 36 11 3

Gold Buttes 2015 125 90 35 32 21 1

Clan Alpine Mtns 2018 475 320 155 46 16 1

Totals/Avg 5,965 3,068 2,897 44 23

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

Mormon Mtns 1980/1994 440 320 120 40 27 6

Sheep Range 1986 850 225 625 ?? 30 14

Badlands 1999 100 33 67 46 33 12

Specter Range 2002 130 130 0 38 21 11

Santa Rosa Range 2003 320 150 170 58 29 6

Hiko Range 2004 100 75 25 40 30 6

Mt Moriah 2007 95 90 5 67 32 6

Egan Range 2001 60 15 45 38 ? 14

Ruby Mountains 2009 160 40 120 50 60 5

East Humboldt Range 2009 180 20 160 50 30 6

Pilot Range/Leppy Hills 2010 115 45 70 45 23 9

Pancake Range 2011 320 220 100 44 23 5

Snowstorm Mtns 2011 125 30 95 44 25 5

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

Mormon Mtns 1980/1994 440 320 120 40 27 6

Sheep Range 1986 850 225 625 ?? 30 14

Badlands 1999 100 33 67 46 33 12

Specter Range 2002 130 130 0 38 21 11

Santa Rosa Range 2003 320 150 170 58 29 6

Hiko Range 2004 100 75 25 40 30 6

Mt Moriah 2007 95 90 5 67 32 6

Egan Range 2001 60 15 45 38 ? 14

Ruby Mountains 2009 160 40 120 50 60 5

East Humboldt Range 2009 180 20 160 50 30 6

Pilot Range/Leppy Hills 2010 115 45 70 45 23 9

Pancake Range 2011 320 220 100 44 23 5

Snowstorm Mtns 2011 125 30 95 44 25 5

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

Mormon Mtns 1980/1994 440 320 120 40 27 6

Sheep Range 1986 850 225 625 ?? 30 14

Badlands 1999 100 33 67 46 33 12

Specter Range 2002 130 130 0 38 21 11

Santa Rosa Range 2003 320 150 170 58 29 6

Hiko Range 2004 100 75 25 40 30 6

Mt Moriah 2007 95 90 5 67 32 6

Egan Range 2001 60 15 45 38 ? 14

Ruby Mountains 2009 160 40 120 50 60 5

East Humboldt Range 2009 180 20 160 50 30 6

Pilot Range/Leppy Hills 2010 115 45 70 45 23 9

Pancake Range 2011 320 220 100 44 23 5

Snowstorm Mtns 2011 125 30 95 44 25 5

Notable Bighorn Herds known to have been impacted by Pneumonia event since 1980s - continued

Herd Year of Event Past Pop Est 2019 Pop Est Adult lossesPast Lamb

RatioCurrent Lamb

Ratio# Yrs compromised Lamb recruitment

White Pine Range/Duckwater Hills 2011 180 100 80 50 18 6

McCullough Range 2012 450 210 240 42 14 5

Spring Mountains 2013 300 140 160 38 18 3

Last Chance Range 2013 180 150 30 37 24 2

Eldorado Mountains 2013 200 80 120 33 18 5

River Mtns 2013 270 200 70 41 17 5

Stonewall Mtn/NTTR 2014 330 175 155 41 8 4

Montana Mtns 2015 90 0 90 50 N/A --

Bare Mountain 2015 250 160 90 40 10 3

Newberry Mtns 2015 120 50 70 36 11 3

Gold Buttes 2015 125 90 35 32 21 1

Clan Alpine Mtns 2018 475 320 155 46 16 1

Totals/Avg 5,965 3,068 2,897 44 23

Establishing Bighorn Ewe Hunts

• Series of meetings where the need to have ewe hunts was requested by game biologists

• Ewe Hunt regulations approved by Commission in 2013

• Ewe Hunts Criteria for biologist to consider

• seasonal or yearlong habitat resource limitations

• past cyclical declines associated with record high population size

• and/or proximity to known disease risk

• Translocation opportunities for low risk translocations will always be considered first

• Identify the key limiting factor to the herd

• Review population estimate and identify population objective based on the limiting factor

• Review recruitment rates, propose number of ewes to remove, and over how many years to reach population objective

• Accounting for hunter success rates, recommend tag quota for residents and nonresidents

• Population objectives will be revised annually as habitat conditions and bighorn behavior change.

Year Unit Season Resident Nonres Resident Nonres Harvest DNH % Success

2014 212 Oct 5 - 25 54 N/A 35 0 25 4 71%

2014 213 Oct 5 - 25 48 N/A 30 0 23 5 77%

2014 268 Oct 5 - 25 61 N/A 20 0 14 4 70%

2014 068 Nov 6 - 30 56 N/A 15 0 10 2 67%

Totals 219 100 0 72 15 72%

2015 212 Oct 5 - 25 44 N/A 40 0 28 5 70%

2015 213 Oct 5 - 25 43 N/A 40 0 28 3 70%

2015 253 Oct 5 - 25 28 N/A 20 0 15 3 75%

2015 268 Oct 5 - 25 81 N/A 40 0 28 3 70%

2015 068 Nov 6 - 30 10 N/A 10 0 6 2 60%

Totals 206 150 0 105 16 70%

2016 212 Oct 5 - 25 48 6 35 4 27 7 77%

2016 213 Oct 5 - 25 47 12 35 4 30 3 86%

2016 253 Oct 5 - 25 23 5 18 2 15 4 83%

2016 268 Oct 5 - 25 71 8 45 5 32 8 71%

2016 068 Nov 6 - 30 104 N/A 10 0 6 2 60%

Totals 293 31 143 15 110 24 77%

TagsApplications

Season, Tags, and App History for Bighorn Ewe Hunts

Year Unit Season Resident Nonres Resident Nonres Harvest DNH % Success

2017 212 Oct 5 - 25 116 35 31 3 18 6 58%

2017 213 Oct 5 - 25 88 21 45 5 35 7 78%

2017 253 Oct 5 - 25 59 5 18 2 12 1 67%

2017 268 Oct 5 - 25 173 35 40 5 29 4 73%

2017 068 Nov 6 - 30 252 N/A 2 0 2 0 100%

Totals 688 96 136 15 96 18 71%

2018 212 Oct 5 - 25 159 65 18 2 13 2 72%

2018 213 Oct 5 - 25 176 63 40 4 28 8 70%

2018 253 Oct 5 - 25 68 19 13 1 11 1 85%

2018 268 Oct 5 - 25 342 87 50 6 33 5 66%

2018 068 Nov 6 - 30 389 N/A 2 0 1 0 50%

Totals 1134 234 123 13 86 16 70%

2019 213 Oct 5 - 25 50 5

2019 268 Oct 5 - 25 60 7

2019 068 Nov 6 - 30 1 0

111 12

Season, Tags, and App History for Bighorn Ewe Hunts - Continued

Applications Tags

Key points considered for translocations vs. ewe hunts to achieve population objectives

• If we knew then what we know now, we would not have conducted several translocations

• Pneumonia and its resulting impact on lamb recruitment is the single biggest impact on bighorn restoration west wide

• Nevada’s successful bighorn restoration program and the risk of disease transmission are the 2 main reasons we have implemented ewe hunts

• NDOW is actively collaborating with Nevada Woolgrowers and NDA to maintain effective separation. To force bighorn translocations closer to public and private land domestic sheep operations is disingenuous

Considerations and key points - continued

• Conducting bighorn translocations takes extensive planning, often over years, with key stakeholders.

• On going efforts are underway with stakeholders to reduce constraints and challenges and increase the probability of success.

• Utah Division of Wildlife Resources is the only agency willing to accept desert bighorn sheep as part of their limited restoration efforts.

• Other states have initiated ewe hunt regulations. Colorado and Montana have hunted ewes for decades, New Mexico and Washington since 2012, Utah approved hunts 1.5 years ago with the first hunt in 2020, Oregon approved regulations this year, and Wyoming has issued ewe licenses in the past but not currently

Considerations and key points - continued

• Our mandate to manage the wildlife resource for the citizens of Nevada guides our stringent criteria for translocating bighorn.

• We harvest females in all of these species to manage herds were necessary. Providing big game hunting opportunities as a viable management tool and recreational sport is a core mission of NDOW.