Dr. John Dindo , Dauphin Island Sea Lab
description
Transcript of Dr. John Dindo , Dauphin Island Sea Lab
Red snapper (Lutjanus campechanus) research at Dauphin Island Sea Lab
Dr. John Dindo, Dauphin Island Sea Lab
OUTLINEPART I: Red
snapper and a history of the fishery
PART II: Habitat creation and restoration
PART III: Red snapper population assessment
Overview of Red Snapper Fishery
History of the Red Snapper Fishery
Clay E. Porch, Stephen C. Turner, and Michael J. Schirripa. 2004. The commercial landings of red snapper in the Gulf of Mexico from 1872 to 1962. SEDAR7-AW-22 (data 1880-1962).John R. Poffenberger and Stephen C. Turner. 2004. Documentation on the preparation of the database for the red snapper stock assessment SEDAR workshop. SEDAR7-AW-17rev. (data 1962-2003)
2007 New Snapper Regulations???
U.S. Landings of Red Snapper in U.S. Waters 1880-2003
1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 20000
1000000
2000000
3000000
4000000
5000000
6000000
7000000
Com
mer
cial
Lan
ding
s (lb
s)
EastWest
Beginning of oil exploration in western gulf
big drop as fleet spends more effort off Campechemove to Campeche complete
increasing local catch by “boats” (vessels <5 tons)Great Depression
World War IIBoat building boom
Table 1: Commercial and recreational red snapper fishery regulations, 1984-2009. C stands for commercial, R for recreational
C R C R C R C R R only1984-1989 13 13 365 365 na na na no bag limit
1990 13 13 365 365 3.1 na 2.65 3.09 71991 13 13 236 365 2.04 1.96 2.21 1.36 71992 13 13 95 365 2.04 + 1.96 3.11 2.1 71993 13 13 94 365 3.06 2.94 3.37 3.62 71994 14 14 77 365 3.06 2.94 3.22 5.57 71995 15 15 52 365 3.06 2.94 2.93 4.53 51996 15 15 87 365 4.65 4.47 4.31 3.69 51997 15 15 73 330 4.65 4.47 4.81 3.47 51998 15 15 72 272 4.65 4.47 4.68 4.37 41999 15 16 70 240 4.65 4.47 4.88 4.35 42000 15 16 66 194 4.65 4.47 4.84 4.35 42001 15 16 79 194 4.65 4.47 4.63 3.33 42002 15 16 91 194 4.65 4.47 4.78 3.56 42003 15 16 94 194 4.65 4.47 4.41 4.87 42004 15 16 105 194 4.65 4.47 4.65 4.6 42005 15 16 131 194 4.65 4.47 4.1 5.02 42006 15 16 126 194 4.65 4.47 4.65 - 42007 13 16 365 IFQ 194 3.315 3.185 3.18 - 22008 13 16 366 IFQ 65 2.55 2.45 2.48 - 22009 13 16 367 IFQ 75 2.55 2.45 2.55 4.27 2
Daily Bag Limit (Fish)Year
Size Limit (inches TL) Calendar Days Open Quota(C)/Allocation(R) (million pounds)
Harvest (million pounds)
Alabama’s Artificial Reef System
LA
ALMS FL
Total Area = 3,108 km2
Estimated over 20,000 structures deployed since 1958
Corp of Engineers pre-permitted since 1987
Hugh Swingle Area• MRD Reefs consist of
Liberty ships, tanks, barges, toppled rigs, and concrete bridge rubble
• Recreational fisherman can deploy “private” reefs with pre-approved materials
• USA deploys and maintains concrete aggregate research modules within Hugh Swingle
Courtesy ALMRD
Habitat Creation & Restoration• Builds on 10 year tagging program: existing reefs installed
1998
• Primary study units: ~ 18 ”private” reef complexes (reef balls, grouper ghettos)
• Additional artificial reefs sampled: 12 public reefs (tanks, ships, barges, bridge rubble)
Abundant Target Species
Gag Grouper ScampVermilion Snapper
Red GrouperRed Snapper Grey Triggerfish
Sampling Methods
• 8 stations fished 30 min each
• Fishing effort: 10 anglers with bottom & sow rigs
• Size measurements (FL/TL)
• Target fishes are tagged & released, & condition index is recorded
• Recapture information gathered from fishermen
Fishers’ Recoveries
Net movement from NCG to east, southeast
Little observed movement to west
slide courtesy of Will Patterson
ROV Work
Red snapper population assessment• Multi-gear sampling
program designed to address critical data needs for future stock assessment
Side scan sonarBottom trawlROVVertical longlineBottom longline
8 9 8 8 8 72 9
3 0
3 1
M S
M o b i l e B a y , A L
F L
M a r c h 2 0 1 0A p r i l 2 0 1 0 M a y 2 0 1 0 J u n e 2 0 1 0 A u g u s t 2 0 1 0
Size class (mm FL)
50 -
100
101
- 150
151
- 200
201
- 250
251
- 300
301
- 350
351
- 400
401
- 450
451
- 500
501
- 550
551
- 600
601
- 650
651
- 700
701
- 750
751
- 800
801
- 850
851
- 900
Siz
e Fr
eque
ncy
0
25
50
75
150
175
200
225
250
275
Bottom longlineTrawlVertical longline
Red snapper size by gear type
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
Red
Snap
per/
hook
/5 m
in.
Month
MarchAprilMay *August *
Red snapper CPUE by month (2010)
Acknowledgements
Captains Mike and Skipper Theirry and the crew of the boats “Lady Ann” and “Escape”
Tech Support, boat time, fishing volunteers and graduate students