1 dr. jeffrey j. lusk, nebraska game & parks commission

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Dr. Jeffrey J. Lusk, Nebraska Game & Parks Commission

OutlineOutline Captive propagation The Surrogator: What is it? The Pheasant Decline Objectives and Methods Results Conclusions Caveats

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Captive PropagationCaptive Propagation Dilutes genetic diversity Introduces diseases Low survival rate Reproduction lower among survivors Costly

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The SurrogatorThe Surrogator

What is it?Provides food, water,

shelter, and warmthBobwhites & Pheasants

How does it work?1 day old chicksMinimum human contactRelease pheasants at 4

weeks old

~$1800.00 + s/h

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The SurrogatorThe Surrogator

What is it supposed to do?Keeps birds in “wild” state

○ Avoid predators○ Improve survival

Imprints chicks on a location○ Chicks stay in area○ Available for later harvest

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The SurrogatorThe Surrogator

Does it work?Developers’ researchGeorgia study with

bobwhites?????

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The Pheasant The Pheasant DeclineDecline

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1960 1970 1980 1990 2000

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68

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Year

Ma

il C

arr

ier I

nd

ex

1955-2007

Nebraska SurrogatorNebraska Surrogator EvaluationEvaluation Objectives

Evaluate survival of pheasants after releaseDetermine return to bag

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Study SitesStudy Sites 2 Controlled Shooting Areas

Jefferson Co.Gosper/Frontier Co.

2 Public Hunting AreasSherman Reservoir WMASacramento-Wilcox WMA

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ApproachApproach Our approach was to deploy the

Surrogator system following the instructions as closely as possible.

We used multiple marking methods to help insure Surrogator birds were identifiable among harvested birds.

We radio tagged a subset of birds placed in Surrogators and followed the fate of these birds until the season opener.

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Study MethodsStudy Methods

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Select site for Surrogator

Purchase rooster chicks Mark chicks with patagial tags Implant radio transmitters for survival

rate estimation on 20 birds at each site Mark all released chicks with

expandable, coiled leg bands Add chemical marker (deuterium) to

water for last 2 weeks in unit

Site Preparation and Site Preparation and Set UpSet Up

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Site Preparation and Site Preparation and Set UpSet Up

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Patagial TaggingPatagial Tagging

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Radio Transmitter Radio Transmitter AttachmentAttachment

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Radio Transmitter Radio Transmitter AttachmentAttachment

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Leg BandingLeg Banding

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Radio-tracking & Radio-tracking & RecoveryRecovery

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Aviary StudyAviary Study Implanted 20 pheasants with radios Pheasants held in aviary at Sac-Wilcox

WMA Determine direct impact of surgery on

survival Banded birds to determine retention Most pheasants released prior to

hunting season

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Harvest Wing Harvest Wing CollectionCollection

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SurvivalSurvival Overall Survival from 30 July release

For every 100 released pheasants, 14 survived until 25 October

Of the 14 that survive, on average 6 would be expected to be harvested

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SurvivalSurvival

Site

Number expected to survive until opener per 100 released

Number of released birds returned to bag (25 OCT – 31 JAN)

CSA1 18 1

CSA2 0 0

Sac-Wilcox 1 2

Sherman 27 3

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Return to BagReturn to Bag Return to bag estimated from harvested

birds with leg or patagial bands11.5% of reported harvest were markedHunter bag returns were 5.4%

One banded bird was a late release from the penned bird study

Cost/pheasant = $36.21 ($3.50 w/o Surrogator)

Cost/pheasant returned to bag = $331.98 ($32.14 w/o Surrogator)

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Aviary Study Results Pheasants implanted on 3 September 3 pheasants died within week of surgery 17 pheasants survived until 27 October 14 of 17 surviving pheasants had both leg

bands 2 surviving pheasants had one leg band 1 surviving pheasant had slipped both leg

bands 1 pheasant lost its radio

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ConclusionsConclusions Survival rates were generally low at all

sites Retention of tags and radios was high Mortality from surgery in aviary birds low Return to bag of Surrogator pheasants

low

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CaveatsCaveats 1 year study Variability in survival among sites Transmitter effects beyond mortality

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