VDGIF Activities Update: Blue Catfish

VDGIFActivitiesUpdate:BlueCatfish
AaronBunch
BobGreenlee
DepartmentofGameandInlandFisheries
CharlesCity,Virginia
[email protected]
ShiftTowardsSlowerGrowth
ShiftTowardsSlowerGrowth
SignificantDeclinesinLengthatAge
Total Length (mm)
Over 13 years to reach 600 mm
RappahannockRiver2002v2014
Age (Years)
WeightatCapturePamunkeyRiver
16.0
14.0
Weight (g)
12.0
10.0
8.0
6.0
4.0
2.0
0.0
0
1
2
3
4
5
6
Age
7
8
9
10
11
12
2014 Data
2014 Data
PowellCreekPopulationEstimates
JamesCatchRateData
AnglerCitationsData
Blue Catfish Citations – James River
RappahannockRiverCatfishTargetedElectrofishing(LF)
Telemetry
•
Low-frequencyelectrofishingcollectfishinRappahannockandPamunkey
•
30Vemco acoustictags(V9orV13)surgicallyimplantedperriver(N=60total)–
allreleasedinuppertidalsections
•
10tagseachsizegroup(350-500mm,501-650mm,&>650mmTL)perriver
•
Secondarytags(Floytag& adiposeclip)
Telemetry
•
Passivetracking
– Supplementedexistingarrays:Pamunkey=30,
York=11,Rappahannock=9
•
Activetracking
– WeeklytrackingusingVemco VR100unitw/
directional&omnidirectionalhydrophoneforfirst
2months,thenmonthlythereafteruntilbatteries
expire(throughJuly2017)
– Movedw/tideevery300-600meters;listeningfor
5minutes
– Waterquality(DO,temp,salinity,conductivity)
takenateachdetectionlocationat##depth
PreliminaryResults
PreliminaryResults
Pamunkey River
What’snext
•
AnalysesofextantdatasetsincooperationwithVirginiaTech
•
Assessmentofmanagementoptionsandpotentialoutcomes