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