Minimizing discard mortality in the red snapper fishery in the Gulf of Mexico

Minimizing discard mortality in the red Minimizing discard mortality in the red snapper fishery in the Gulf of Mexicosnapper fishery in the Gulf of Mexico

Greg Stunz, Ph.D.Greg Stunz, Ph.D.Endowed Chair for Fisheries and Ocean Health, andEndowed Chair for Fisheries and Ocean Health, and

Professor of Marine BiologyProfessor of Marine BiologyTexas A&M UniversityTexas A&M University--Corpus ChristiCorpus Christi

The SportThe Sport--fish Research Group at HRIfish Research Group at HRI

Goal: Provide sound science for maintenance and Goal: Provide sound science for maintenance and rebuilding of sportrebuilding of sport--fisheries for future generationsfisheries for future generations

““iSnapperiSnapper””An innovative tool for An innovative tool for collecting data in the collecting data in the

ForFor--Hire Fishery Hire Fishery (aka charters)(aka charters)

Red Snapper Recreational CatchRed Snapper Recreational CatchSource: iSnapper Pilot Data, Summer 2011Source: iSnapper Pilot Data, Summer 2011

Red Snapper Recreational CatchRed Snapper Recreational CatchSource: iSnapper Pilot Data, Summer 2011Source: iSnapper Pilot Data, Summer 2011

Reduced foragingability

Lingering Barotrauma

Depredation

The The ““Discarded AliveDiscarded Alive”” SliceSlice

hitech‐dolphin.com

Photo credit:  ChrisPederick.com

Acoustic Deterrent Devices (ADD):Acoustic Deterrent Devices (ADD):.

AQUAmark 200 Cetacean AQUAmark 200 Cetacean Deterrent DeviceDeterrent Device

Photo credit:  ChrisPederick.com

Pilot StudyPilot Study

ADDADD in Actionin Action

Experimental Design

Photo credit:  ChrisPederick.com

Future?Future?

Recent Barotrauma StudiesRecent Barotrauma Studies.

•• Vent vs nonVent vs non--ventvent•• Depth effectsDepth effects•• Rapid recompressionRapid recompression

Controlled Laboratory ConditionsControlled Laboratory ConditionsField ConditionsField Conditions

VentedVented NonNon‐‐VentedVented

Results:Results:

Release Treatments:Release Treatments:

n=30

n=30

Design:Design:

Methods:Methods:

Seasonal Field Survival

Methods:Methods:

SummarySummary

•• ADD, venting, and recompression all show promiseADD, venting, and recompression all show promise

•• A clear seasonal effect on mortalityA clear seasonal effect on mortality

•• We would recommend venting, especially during summerWe would recommend venting, especially during summer

•• More work to be doneMore work to be done

• Better characterize this “problem” in the Gulf of Mexico?

• What are the root causes of depredation events?

• How useful are ADDs as a technique to mitigate depredation by dolphins and increase discard survival?

• Fin recognition program, are the problem pods of dolphins?

• Is there a “dinner bell” effect?

• Work with marine mammalogists that can better understand behavioral responses. 

Future ADD StudiesFuture ADD Studies

AcknowledgementsAcknowledgements

Research Scientists, PostResearch Scientists, Post--Docs, Graduate Students, and Student Workers:Docs, Graduate Students, and Student Workers:

Megan RobillardMegan Robillard Jason WilliamsJason Williams Jennifer WetzJennifer Wetz

Matt AjemianMatt Ajemian Judd Curtis Judd Curtis Matt JohnsonMatt Johnson

Peter Young Peter Young Phil JosePhil Jose Alison LundAlison Lund

Will McGlaunWill McGlaun Ruben PalaciosRuben Palacios Maurico ManceraMaurico Mancera

NOAA Fisheries NOAA Fisheries –– Marine Fisheries InitiativeMarine Fisheries Initiative

NOAA NOAA –– Cooperative Research ProgramCooperative Research Program

Harte Research Institute for Gulf of Mexico StudiesHarte Research Institute for Gulf of Mexico Studies

Texas A&M University Texas A&M University –– Corpus ChristiCorpus Christi

www.fisheries.tamucc.eduwww.fisheries.tamucc.edu www.harteresearchinstitute.orgwww.harteresearchinstitute.org