Index | Overview | Methodology | Coral standards | Fish standards | Calibration | Data processing | Data sheets
Data processing and reporting
There are many ways to process and analyze data collected
from AGRRA surveys, some of which are presented below. We recommend three levels
of data processing. Level I is focused on determining means and standard
deviations for the parameters measured. Level II is a more detailed look at
size frequency distributions and mortality (at various spatial scales), and
Level III includes making more detailed statistical comparisons between the
data. Below is the basic Level I approach to AGRRA data. We request that all
AGRRA data be initially entered into the preformatted (Level I) spreadsheets
that we provide. This will ensure consistency in the way data are reported.
Furthermore, the data structure will be compatible with the AGRRA database
located at the Level I For Level I, there are two pre-formatted Excel spreadsheet files to make data processing and analysis easier and more standardized. The first Excel file is the Benthic spreadsheet which is for processing and analyzing coral information (abundance, size, condition, etc.) and algal abundance. The second file is the Fish spreadsheet to process and analyze data collected from the fish belt transects. For data collected using the rover diver fish method, refer to the manual by Schmitt et al. (1998).
Benthic spreadsheet data entry After each dive, verify data for accuracy and completion. Then, transfer all transect data from the benthic survey datasheets directly into the pre-formatted Benthic spreadsheet for each site surveyed (Figure 1). The Benthic spreadsheet is similar to the datasheet so that it is easy to enter both coral, algae and Diadema data. Note that some data cells are calculated and not entered (see * in Figure 1). Each site will have its own spreadsheet file. Enter all the data for an entire transect at a time, then enter the data for the next transect directly beneath, without skipping a row. After all data are entered, recheck for any errors or mis-entries. IMPORTANT: For mortality data, DO NOT enter zeros if one category is 100%
Benthic data processing The spreadsheet also has built-in macros that automatically compute site averages, standard deviations, and ratios for all corals surveyed (Figure 2 - top box) and also for specific selected corals (Figure 2 - bottom box).
Fish spreadsheet data entry and processing After each dive, verify data for accuracy and completion. Then, transfer all transect data from the fish belt survey datasheets directly into the pre-formatted Fish spreadsheet for each site (Figure 3). Each site will have its own spreadsheet file. The Fish spreadsheet is similar to the datasheet so that it is easy to enter data. Note that some data cells are calculated and not entered (see * in Figure 3). For each transect enter the data under the appropriate transect number. As you enter transect data, the average density and size is computed for each transect. These data are summed to provide total averages (# fish, density and size) for all transects combined. After all data are entered, recheck data for any errors or mis-entries.
Data reporting
AGRRA database The
AGRRA database designed in Microsoft Access is located at the Rosenstiel School
of Marine and Atmospheric Science,
Submitting
data We request that team leaders send us electronic copies of their data (as excel spreadsheets). To do this first check and verify your data for completion and accuracy. Send electronic data either by e-mail or on a disk to:
AGRRA reports In addition, we are requesting that team leaders submit a Report on their
findings. Currently we are in the process of publishing a special AGRRA volume
that will contain individual data reports (submitted by team leaders) from 18
surveys completed to date and a synthesis of the condition of coral reefs in
the All reports should have the following format (see below for
more details): Title
Report 1: Coral, Algae, and Diadema The purpose of the benthic reports is to characterize the coral and algal communities, summarize their condition or status, and discuss linkages between coral, algal and fish communities. Below are guidelines for these reports. Introduction Methods Results Figure 1. Site location map showing location of area and
specific survey sites Table 1: Site information
* provide variance Figure 2a-b. Coral
species composition (a=shallow, b=deep sites), Pie graph showing % relative
abundance Figure
3a-b. Coral recruitment species composition (pie graph of abundance % of
recruits). Table 2.
* provide variance Figure 4a.b. Size frequency distributions for dominant
species at each reef type (e.g., Acropora, Montastraea spp.). Use the
following categories: <20; 20-30; 30-40; 40-50; 50-60; 60-70; 70-80; 80-90;
90-100; 100-110; 110-120; 120-130; 130-140; 140-150; 150-160; 160-170; 170-180;
180-190; 190-200; >200 cm. Figure 5a-b.: Frequency of old mortality and recent mortality (all shallow; or all deep sites)- use the following categories: 0-10%; 10-20; 20-30; 30-40; 40-50; 50-60; 60-70; 70-80; 80-90; 90-100% Table 3
* provide variance Figure 6. Open Figure 7. Open View example graphs for AGRRA data reporting Discussion
Focus should be on interpreting AGRRA indices of benthos condition (coral mortality, coral condition, coral cover, coral size-frequency distributions, coral recruitment, algal abundance) in the context of establishing the current status of the system. Discussion can encompass spatial patterns, recent disturbances (hurricanes/1998 bleaching), dynamics of algae and fishes on coral condition, relationships to chronic conditions (poor water quality, overfishing), comparing (statistically) one area to another (note please limit comparisons to your own study area), or comparing surveys of the same area done at two different times. Summarize your findings and overall impression of the benthos with respect to its condition.
Report 2: Fish communities The purpose is to characterize fish communities, summarize their status and discuss linkages with benthic parameters. Introduction Methods Results Figure 1. Site location map showing
location of area and specific survey sites Table 1: Site information
* provide variance Figure
2a-b. Fish species composition (a=shallow, b=deep), Bar graph showing fish abundance
(#/100 m2) for all shallow or deep sites combined by major family (e.g.,
Scaridae). Include error bars showing variances. Table 2.
Figure 3a.b. Size frequency distributions for major 2 guilds-carnivores (grouper, snappers) and herbivores (parrots, surgeonfish, yellowtail damsel)- all shallow or deep sites combined. Use the following size categories (0-5, 6-10, 11-20, 21-30, 31-40, >40 cm). Table 3
Density can be substituted for biomass (above), **provide
variance Figure 4. Regression plot between herbivore biomass (or
density) and macroalgal index with all sites plotted. Figure 5. Multiple regression between fish biomass (or density)
of all or selected families and benthic habitat variables (coral cover, size,
depth, coral mortality, other). Figure 6. Open Figure 7. Open View example graphs for AGRRA data reporting
Discussion
Fish species richness data reporting
A
summary of your fish data collected using the roving diver method is also
incorporated into your report. The raw data is reported directly to REEF and
their database which encompasses over thousands of reports from around the
world. REEF provides instructions for completing and reporting roving diver
surveys collected on their website (www.reef.org/)
or their training manual (Schmitt, E.F., D. Wells Feeley, and K.M. Sullivan
Sealey. 1998. Surveying Coral Reef Fishes: A Manual for Data Collection,
Processing, and Interpretation of Fish Survey Information for the Tropical After the dive, you transfer your data using pencil to the REEF Survey Scan Sheet (do not use photocopies), following the instructions on the Scan sheet. Verify data for accuracy and completion. After REEF receives the scan sheet, they verify the data for quality control and completion; scan it into the computer, then post it on the REEF website.
Index | Overview | Methodology | Coral standards | Fish standards | Calibration | Data processing | Data sheets
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