Mule Deer Informational AGENDA #19-C MODELS AND POPULATION ESTIMATES

CODY SCHROEDER – NDOW GAME DIVISION

Harvest Data

SurveyData

Population Models

Quota Array

The Process: How do we develop quota recs?

Population Models: Why do we estimate numbers?

No survey method has perfection detection to count all animals

Populations constantly change because of mortality, births, immigration, emigration

To provide an estimate of abundance for tag allocation (quota)

Limiting factors

Harvest Data

▪ Mandatory harvest reporting for all big game species

▪ New system, 98% reporting rate

▪ Sex

▪ Age

▪ Hunt Unit or Unit Group

▪ # of antler points

▪ # animals wounded or tracked

Deer Status: Harvest Trends

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2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

% 4

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Statewide % 4-Point or greater

% 4 point or greater

▪ NDOW uses a deterministic spreadsheet model

▪ Deterministic = no stochasticity (random variation)

▪ Basic input parameters

▪ Initial population size

▪ Recruitment data (fawn:doe ratio)

▪ Harvest data (we subtract bucks, does, and fawns)

▪ Survival rates

▪ Buck:doe ratio used a qualitative measure to calibrate models

Population Models: How do we estimate populations?

Population Models: Integrated Population Models

Count Data Telemetry Data Harvest Data Environmental Covariates

Integrated Population Model

PopR software developed by Dr. Paul Lukacs and Josh Nowak

University of Montana

Contracted through 2021

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Pop Estimate

Deer Harvest

Selleck-Hart Estimator

Change-in-Ratio

Model

Spreadsheet

Model

NDOW Heritage Program$25 million spent to date

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Fawn:Adult Ratio 3 per. Mov. Avg. (Fawn:Adult Ratio)

Summary of Agenda Item #19-C

q Process of quota development

q NDOW uses models to estimate populations

q Inputs include survey data, harvest data, survival rates

q Population trends have fluctuated over time

q In process of developing new web-based models

Mule Deer InformationalAGENDA # 19-D DEVELOPMENT OF QUOTAS FROM SURVEY AND POPULATION DATA

CODY SCHROEDER – NDOW GAME DIVISION

/1

Determine # animals available for harvest

• Population estimate

• Buck to Doe Ratio

2

Distribute harvest into weapon classes

• Based on previous year’s demand

3

Expand harvest to quotas

• Divide harvest rate by hunt success (%)

Quota Development Process:

Demand:Measure of interest based on 1st Choice applications from year prior

ARCHERY MUZZELOADER ANY LEGAL WEAPON

Mule Deer : Hunt Success

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Resident Antlered Mule Deer Hunt Success

Archery Muzzleloader ALW

Quota Development Process: 2019 MULE DEER QUOTA ARRAY

UNIT GROUP: 171-173 - Northwestern Nye and Southern Lander Counties

PREHUNT ESTIMATE % YOUTH HUNT HUNT

ADULT ADULT BUCK HARVEST Comp. 1235 1235

BUCKS DOES RATIO AS DOES Tags % Success Early Late

1150 2543 45 39% 16 4

TOTAL 3693

RATE DESIRED HUNT FIRST CHOICE Antlerless

OF DOE DOE 1181 APPLICATIONS--DEMAND HUNTER

HARVEST HARVEST QUOTA RIFLE MUZZL. ARCH. YOUTH RIFLE MUZZL. ARCH. SUCCESS

0% 0 0 53.7% 6.1% 15.1% 53.5% 32.0% 26.3% 9.3%

POST HUNT HUNT HUNT HUNT HUNT HUNT HUNT

HUNT 1331 1371 1341 1107 1331 1371 1341

BUCK DESIRED REPRTD. RES. RES. RES. RES. NR. NR. NR. RES. NR

RATIO BUCK BUCK RIFLE MUZZL. ARCH. RIFLE MUZZL. ARCH. TOTAL TOTAL

OBJ. HARVEST HARVEST QUOTA QUOTA QUOTA QUOTA QUOTA QUOTA QUOTA QUOTA QUOTA

30 387 322 487 75 180 144 34 8 20 886 78

THREE YEAR AVERAGE

HUNTER SUCCESS RATES

Mule Deer Harvest Guidelines

25 – 35 Bucks per 100 DoesStandard

• Most Units across the state

30 – 40 Bucks per 100 DoesAlternative

• WR – 014, 194-196

• ER – 065, 081, 114-115, 131-134

• SR – 221-223, 241 - 245

Hunt Success (3 yr avg)Non-Standard

• 35 – 45% for 6 Unit Groups

• ≥ 45% for 8 Unit Groups

Public Process

NDOW

CABs

General Public

Wildlife Commission

QUOTA

Public Review and Wildlife Commission Processo NDOW posts official quota recommendations in late

April

o County Advisory Boards (CAB’s) receive NDOW quota recommendations

o CAB’s hold public meetings to discuss quota recommendations

o Nevada Board of Wildlife Commission meeting in May to approve NDOW’s quota recommendations

o General public and CABs provide input

o Commission makes final decision on tag quotas

Mule Deer Restoration Effortso$25 million dollars spent on sagebrush habitat

restoration by Heritage Program since 1996oBenefits mule deer and many other wildlife

species

oOver 800 mule deer radio-collared by NDOW since 2010oMap crucial habitat and corridors

oSurvival rates

oCollect information on body condition

Summary of Agenda Item #19-D

q Quota process is a 3-step process

q Quota array based on demand/success

q Population estimate

q Demand (previous year)

q Hunt success (3-year avg)

q Resident (90%) Non-resident (10%) split

q Public process involving NDOW, CABs, Wildlife Commission

q NDOW has spent millions of $$ in habitat and research on mule deer over last two decades

Thank You