Reef growth stage: 1. Fringing reef 2. Barrier reef 3. Atoll.
Results of AGRRA Surveys of Twenty Western Atlantic Reef Areas
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Transcript of Results of AGRRA Surveys of Twenty Western Atlantic Reef Areas
Results of AGRRA Surveys of Twenty Western Atlantic Reef AreasCompiled by Philip Kramer, Robert Ginsburg and Judith Lang
from the assessments of AGRRA teams
Rosenstiel School of Marine and Atmospheric Science, University of Miami
Ocean Research and Education Foundation
Atlantic and Gulf Rapid Reef AssessmentAtlantic and Gulf Rapid Reef Assessment
(AGRRA)(AGRRA)
Goals
• Develop a regional scale of reef condition
• Identify end member reefs in serious decline and candidates for protection
•Provide region-wide comparative data
• Map spatial patterns of reef condition
•Identify reefs for monitoring programs or marine protected areas
A tla ntic a n d G ulf R a p id R ee f A sse ssm ent(A G R R A )
P R O T O C O L
(1) Corals:10m line transects
·
Partial coral mortality
·
Colony size distribution
·
Identify incidences of bleaching and disease
·
Coral cover
(2) Algae:
25cm2 quadrats
·
Relative abundance of macro, turf, coralline
·
Macroalgal height
·
Diadema surveys
(3) Fishes:
30m x 2m belt transects
·
Abundance and size of key species
·
Commerically significant(groupers, snappers)
·
Important grazers (parrotfish blue tangs)
·
Indicator species (damselfish)
REEF Rover Diver census
·
Species diversity of all species
O p tion a l C om p o n en ts eas ily a d d edCoral recruitment; Herbivory (fish bites); Video transects
AGRRA Sampling effort
Coral Cover by Country
0
5
10
15
20
25
Bahamas Belize CaymanIslands
Cuba Jamaica Turks &Caicos
Perc
en
t (%
)
Coral Cover by CountryCoral Cover by Country
Coral indicator norms
Coral indicator norms cont.
Coral size frequency and mortality
Reef fish abundance and biomass norms
Preliminary health index based on 13 AGRRA indicators
Preliminary ConclusionsCoral cover:• A regional average (n = 20) of 21% BUT• Wide regional variations• Remote reefs reefs near centers of population
Montastraea annularis Complex• Reef structure; habitat for fish and conch/lobster• Increased diseases and bleaching
Elevated SSTs of 1998 ENSO:• Bleaching-induced mortality• Increased coral diseases
Preliminary Conclusions
Indicator of regional overfishing • Low sightings (~<1/100m2) of large-bodied groupers
and snappers
Complex controls on regional reef condition• Environment, biogeography, history• Natural and anthropogenic impacts
A. palmata “Shangri-La”, Cuba’s south coast
Widespread resheeting of A. palmata colonies
n= 650 reefs average = 21%
AGRRA program results
High variability across the region
AGRRA has become a widely accepted tool for assessing and monitoring for MPA’s