Transcript RNA Topic 1

Creating a Large Marine Reserve in the Dry
Tortugas Florida: The Role of Science,
People, Process, & Persistence
Tayrona.org
John H. Hunt & William C. Sharp
Florida Fish & Wildlife Conservation Commission
Fish & Wildlife Research Institute
Dry Tortugas National Park
Dry Tortugas
Marathon
Key West
• Small group of islands ~ 70 miles west of Key West, Florida
• Established by the NPS in 1935 to protect historic Fort Jefferson
• Name changed in 1992 to Dry Tortugas National Park
• Habitat less disturbed than rest of Florida Keys
Spiny Lobster Size-Frequency
Size (mm carapace length)
DTNP
Male
Florida Keys - Fishery
Female
Male
Female
180
100
20
120
60
0
frequency
60
120
350
0
frequency
350
700
Percent of egg bearers by month and size-class
Dry T
ortug
a
0
J
J
MONTH
m
(m
M
A
S
O
60
ze
A
100
25
)
160
0
CL
CL
)
160
50
100
A
M
J
m
25
75
J
A
MONTH
S
O
60
(m
50
100
ze
75
s
Si
100
Percentage egg bearing
a Key
s
Si
Percentage egg bearing
Florid
Tortugas 2000 Process
• 1998: Florida Keys National Marine Sanctuary
(FKNMS) and NPS stakeholder working group
processes
– Goal: create “ecological reserves” in the
Dry Tortugas
– Balance resource protection and marinerelated stakeholder activities
– Considered factors such as coral reef
and fish spawning locations and popular
fishing areas
National Park Service
General Management Plan
Fall
Winter
Fall
Florida Keys National Marine Sanctuary
Tortugas 2000 Process
Geography and Oceanic Circulation
Downstream Transport From Tortugas
• Retention & recruitment pathways for local & foreign larvae
• Larvae from Tortugas spread via gyres, currents and eddies
• Upwelling and convergence provides food supply to larvae
Habitats Within Park and RNA
(Franklin et al. 2003)
Socio-economic Assessment
Lobster Catch
Reef Fish
Diving
Rec Fish
Tortugas Ecological Reserve
Final Action
• Selected by the
Tortugas 2000
Working Group
& the Sanctuary
Advisory
Council
• Area of ~ 151 nm2
Dry Tortugas National Park Research Natural
Area: The 5-Year Report
Review and Discussion
June 27, 2012
Florida Fish and Wildlife Conservation Commission
Fish and Wildlife Research Institute
Division of Marine Fisheries Management
RNA Topic 1: Quantify changes in abundance
and size-structure of fish species
 Status of reef fish of the Tortugas
region based on fishery-independent
visual and trap survey assessments
– 2000-2011: Assessments of the coral reef
fishes in the Tortugas region were conducted
by a collaborative team of research divers
from the Univ. Miami, NOAA, NPS, and the
FWC
– Since RNA implementation, abundance and
size-structure of legal-sized red grouper,
mutton snapper, yellowtail snapper, and
hogfish has increased in TNER & DRTO
compared to nearby areas open to fishing
A
DRTO
Density = 0.10
Occupancy = 10.7%
TNER
Density = 0.04
Occupancy = 5.3%
RNA
HAU
TBO
Density = 0.19
Occupancy = 21.9%
B
TNER
Density = 0.32
Occupancy = 42.6%
DRTO
Density = 0.26
Occupancy = 33.9%
RNA
HAU
TBO
Density = 0.27
Occupancy = 29.0%
Within DRTO Occupancy
RNA = 34.7%
Open-Use = 32.3%
RNA Topic 1: Quantify changes in abundance
and size-structure of fish species
2000
Tortugas North Ecological Reserve
Density = 0.04
Occupancy = 5.3%
DRTO
Density = 0.10
Occupancy = 10.7%
Future RNA
Tortugas Bank --Open-Use Area
Density = 0.19
Occupancy = 21.9%
RNA Topic 1: Quantify changes in abundance
and size-structure of fish species
 Nursery function of seagrasses within
the Dry Tortugas National Park
Research Natural Area
– Surveys were conducted of fish
associated with seagrass inside and
outside the RNA
– Juvenile red and black groupers were
most frequently collected in the
shallow seagrass beds of the RNA
– Seagrass beds within the RNA likely
function as an important nursery
habitat for juveniles of these exploited
reef fish species in the Tortugas region
RNA Topic 2: Monitor immigration & emigration
of targeted species in the RNA
 Regional connectivity of
fishes within the Tortugas
region of Florida
– Riley’s Hump is a well known
mutton snapper spawning
aggregation site
– Mutton snapper were
acoustically tagged within the
RNA & Riley’s Hump and tracked
with a network of underwater
‘listening outposts’
• Listening Posts
RNA Topic 2: Monitor immigration & emigration
of targeted species in the RNA
 Regional connectivity of
fishes within the Tortugas
region of Florida
– Identified a migratory
corridor used by mutton
snapper between the
RNA and a spawning
aggregation at Riley’s
Hump
– Some mutton snapper
moved from the RNA to
Riley’s Hump as many
as four times per
spawning season
May
83° 05’
83° 00’
82° 55’
24° 30’
24° 35’
24° 40’
TNER
TSER
July
June
82° 50’
RNA
DRTO
RNA Topic 2: Monitor immigration & emigration
of targeted species in the RNA
 Regional connectivity of fishes within
the Tortugas region of Florida
– Number of mutton snapper observed at
Riley’s Hump during expected spawning
times at full moon increased after the
implementation of the RNA
– In 2009, a large aggregation of mutton
snapper and repeated spawning events
were documented for the first time in
Florida
Date
Number of Fish Observed
May 27, 20021
75-100
June 15, 20031
75-100
June 15, 20031
200+
July 4, 20041
300
July 3, 20072
100+
June 11, 20093
~ 4,000
1
Burton et al. 2005. 2 Michael Burton, NOAA, pers. comm. 3 FWC study
Mutton snapper spawning aggregation in the
Tortugas region
RNA Topic 5: Assess reproductive potential of
exploited fishes by evaluating egg production &
larval dispersal
 Larval transport modeling
to assess the reproductive
potential of reef fish
spawning in the Tortugas
region
– Model indicates that spawning
at Riley’s Hump supplies new
reef fish recruits to the Florida
Keys and along the east and
west coasts of Florida
Staff Recommendation
 Staff recommends the Commission continue to support
the Special Regulations established for the RNA that
prohibit fishing and anchoring