Marine Sanctuaries Conservation Series ONMS-09-03

U.S. Department of Commerce

National Oceanic and Atmospheric Administration

National Ocean Service

Office of Ocean and Coastal Resource Management

Office of National Marine Sanctuaries July 2009

Preliminary Comparison of Natural Versus 

Model-Predicted Recovery of

Vessel-Generated Seagrass Injuries in

Florida Keys National Marine Sanctuary
About the Marine Sanctuaries Conservation Series

The National Oceanic and Atmospheric Administration’s National Ocean Service (NOS) administers the 

Office of National Marine Sanctuaries (ONMS). Its mission is to identify, designate, protect and manage 

the ecological, recreational, research, educational, historical, and aesthetic resources and qualities of nationally 

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sciences, socioeconomic and cultural sciences, education, and policy development to accomplish the diverse needs 

of NOAA’s resource protection mandate.
Preliminary Comparison of Natural Versus Model-Predicted 

Recovery of Vessel-Generated Seagrass Injuries in Florida 

Keys National Marine Sanctuary

A. V. Uhrin, M. S. Fonseca, and W. J. Kenworthy

NOAA/NOS Center for Coastal Fisheries and Habitat Research (CCFHR), 101 Pivers 

Island Road, Beaufort, NC 28516

Silver Spring, Maryland

July 2009

U.S. Department of Commerce

Gary Locke, Secretary

National Ocean and Atmospheric Administration

Jane Lubchenco, Ph.D.

Under Secretary of Commerce for Oceans and Atmosphere

National Ocean Service

John H. Dunnigan, Assistant Administrator

Office of National Marine Sanctuaries

Daniel J. Basta, Director
DISCLAIMER

Report content does not necessarily reflect the views and policies of the Office of 

National Marine Sanctuaries or the National Oceanic and Atmospheric Administration, 

nor does the mention of trade names or commercial products constitute endorsement or 

recommendation for use.

REPORT AVAILABILITY

Electronic copies of this report may be downloaded from the Office of National Marine 

Sanctuaries web site at www.sanctuaries.nos.noaa.gov. Hard copies may be available 

from the following address:

National Oceanic and Atmospheric Administration

Office of National Marine Sanctuaries

SSMC4, N/ORM62

1305 East-West Highway

Silver Spring, MD 20910

COVER 

Seagrass bed composed of Thalassia testudinum and Syringodium filiforme (Credit: 

NOAA).

Inset: Vessel-generated seagrass injury in Florida Keys National Marine Sanctuary 

(Credit: NOAA).

SUGGESTED CITATION

Uhrin, A. V., M. S. Fonseca, and W. J. Kenworthy. 2009. Preliminary Comparison of 

Natural Versus Model-predicted Recovery of Vessel-generated Seagrass Injuries in 

Florida Keys National Marine Sanctuary. Marine Sanctuaries Conservation Series

NMSP-09-03. U.S. Department of Commerce, National Oceanic and Atmospheric 

Administration, Office of National Marine Sanctuaries, Silver Spring, MD. 13 pp. 

CONTACT

Amy V. Uhrin, Research Ecologist

NOAA/NOS Center for Coastal Fisheries and Habitat Research, 101 Pivers Island Road, 

Beaufort, NC 28516

E-mail: amy.uhrin@noaa.gov
i

ABSTRACT

Each year, more than 500 motorized vessel groundings cause widespread damage to 

seagrasses in Florida Keys National Marine Sanctuary (FKNMS). Under Section 312 of 

the National Marine Sanctuaries Act (NMSA), any party responsible for the loss, injury, 

or destruction of any Sanctuary resource, including seagrass, is liable to the United States 

for response costs and resulting damages. As part of the damage assessment process, a 

cellular automata model is utilized to forecast seagrass recovery rates. Field validation of 

these forecasts was accomplished by comparing model-predicted percent recovery to that 

which was observed to be occurring naturally for 30 documented vessel grounding sites. 

Model recovery forecasts for both Thalassia testudinum and Syringodium filiforme

exceeded natural recovery estimates for 93.1% and 89.5% of the sites, respectively. For

Halodule wrightii, the number of over- and under-predictions by the model was similar. 

However, where under-estimation occurred, it was often severe, reflecting the wellknown extraordinary growth potential of this opportunistic species. These preliminary 

findings indicate that the recovery model is consistently generous to Responsible Parties 

in that the model forecasts a much faster recovery than was observed to occur naturally, 

particularly for T. testudinum, the dominant seagrass species in the region and the species 

most often affected. Environmental setting (i.e., location, wave exposure) influences 

local seagrass landscape pattern and may also play a role in the recovery dynamics for a 

particular injury site. An examination of the relationship between selected environmental 

factors and injury recovery dynamics is currently underway.

KEY WORDS

Seagrass recovery, vessel groundings, seagrass disturbance, seagrass recovery model, 

Florida Keys National Marine Sanctuary, Mini-312 Program
ii

TABLE OF CONTENTS

Abstract and Key Words....................................................................................................................i

Introduction..........................................................................................................................................1

Methods.................................................................................................................................................2

Results...................................................................................................................................................4

Discussion ............................................................................................................................................6

Acknowledgments..............................................................................................................................7

Literature Cited....................................................................................................................................7
iii

LIST OF FIGURES AND TABLES

Figure 1. Absolute difference between model-predicted and natural percent recovery of 

selected vessel grounding sites in FKNMS...................................................................................5
1

INTRODUCTION

Seagrass beds are an integral component of the south Florida marine ecosystem. Within 

the boundaries of the Florida Keys National Marine Sanctuary (FKNMS) nearly 1.4 

million acres of seagrass function as habitat, settlement sites, nurseries, feeding grounds, 

and refuge for a large number of ecologically and commercially important marine 

organisms (Zieman, 1982; Zieman and Zieman, 1989; Fourqurean et al., 2001). Despite 

the irrefutable significant ecological value of seagrasses, annually more than 500 

motorized vessel groundings cause widespread damage to seagrass habitat in the 

Sanctuary and throughout other regions of Florida (Sargent et al., 1995; Whitfield et al., 

2002; Kirsch et al., 2005; SFNRC 2008). Given the growing popularity of the Florida 

Keys for marine recreation (SCUBA diving, fishing) and commercial fishing, vessel 

groundings will almost certainly continue to occur. 

Vessel groundings are some of the most severe injuries that can occur in seagrass 

meadows (Kenworthy et al. 2002). A typical grounding results in the formation of at 

least one of four features: 1) propeller scars (shallow, narrow, linear excavated trenches 

caused by the propeller while the vessel is still moving), 2) keel scars (usually a 

depression into the seagrass mat when the keel comes to rest as vessel forward movement 

halts), 3) blowholes (deep, large excavations caused by propeller wash as the vessel 

becomes hard aground or the operator attempts to power off) and, 4) berms (excavated 

material deposited on the outskirts of blowholes). Grounding events directly remove

above- and belowground seagrass biomass resulting in features that are highly vulnerable 

to storm events. For example, Whitfield et al. (2002) reported how storms caused 

expansion of injuries by up to 135% of the original area. Given the slow recovery rates 

exhibited by the most frequently injured seagrass species (Thalassia testudinum) in the 

FKNMS (2 – 10 years for propeller scars in Thalassia testudinum: Zieman 1976, Durako 

et al. 1992, Dawes et al. 1997, Kenworthy et al., 2002) and the often cumulative nature of 

vessel groundings, these injuries severely alter both short and long-term seagrass 

ecosystem functions (Sargent et al. 1995, Uhrin and Holmquist 2003, SFNRC 2008). 

Moreover, multiple injuries to a seagrass bed create a scenario where the loss of seagrass 

cover can lead to a state change, shifting what was a seagrass bed to a sparse or nonvegetated state following a storm event (Fonseca and Bell 1998, Fonseca et al. 2000a). 

Under Section 312 of the National Marine Sanctuaries Act (NMSA), any person 

responsible for the loss, injury, or destruction of any Sanctuary resource is liable to the 

United States for response costs and resulting damages and restoration. The two 

governing agencies, the National Oceanic and Atmospheric Administration (NOAA) and 

the Florida Department of Environmental Protection (FDEP), co-operatively conduct 

injury assessments and develop restoration plans for vessel injuries to seagrass resources 

utilizing protocols and analyses established under the auspices of the Mini-312 Program 

(NOAA; Fonseca et al., 2000b; Fonseca et al., 2004; Kirsch et al., 2005). Field impact 

assessments include site mapping and bathymetric surveys using high resolution 

Differential Global Positioning Systems (DGPS) and fathometers, as well as 

characterization of injured habitat by visual assessment methods (Kirsch et al., 2005). 
2

Field data, specifically the spatially articulated injury perimeter measurements, are input 

to a recovery model which uses published data on seagrass growth rates combined with 

injury geometry to compute a recovery trajectory (Fonseca et al., 2004). Restoration 

plans include recommendations for primary restoration (restoration activities within the 

actual grounding site) and compensatory restoration (off-site restoration activities to 

compensate for lost interim ecological services). The level of primary and compensatory 

restoration is determined through a Habitat Equivalency Analysis (HEA) which 

incorporates the recovery model output and economic discounting (NOAA, 1997; 

Fonseca et al. 2000b). 

Given that natural recovery may take place under suitable conditions, the ability to 

forecast whether or not an injury could potentially recover without intervention or with 

minimal restorative action would enable management to focus efforts on those sites 

where recovery is less likely. The need to validate the model recovery predictions is 

critical. Prior to this report we had been unable to conduct a comparison of our recovery 

model with what was actually transpiring at the injured sites. To that aim, we reassessed 

30 Mini-312 grounding incidents where restoration had yet to be implemented. At each of 

the sites we examined the change in area of blowhole features as well as the change in 

percent cover of seagrass within blowholes. We compared recovery trajectories 

generated from the recovery model to the observed natural recovery at each site to 

validate model performance. 

METHODS

Site Selection

In March 2004, we consulted the NOAA Damage Assessment Center (DAC) database of 

reported seagrass vessel grounding sites in FKNMS and chose a subset of sites where 

restoration had yet to be executed. The widespread geographic distribution of grounding 

sites in FKNMS made it necessary to limit the number of sites to a manageable subset. 

We considered injury age (e.g. passage of time) to be highly influential in the recovery 

process as it has been shown that seagrasses will grow and re-colonize an area where they 

previously existed given enough time, and barring further disturbance (Thayer et al. 

1994). Thus, the available sites were initially grouped using the inter-quartile ranges

(IQR) for injury age, calculated using PROC UNIVARIATE in SAS Version 9.1 (SAS 

Institute, Inc. 2002). Within each of the four age quartiles (< 1.43 years, 1.43-1.95 years, 

1.96-2.88 years, and 2.89-6.33 years), sites were further categorized according to relative 

wave exposure (RWE). RWE was determined by applying the Wave Exposure Model 

(WEMo; Malhotra and Fonseca 2007) to each injury for the time period beginning from 

the date of the first injury assessment through present day. RWE was chosen as an initial 

categorization variable due to its strong link with seagrass landscape pattern (Patriquin 

1975, Fonseca and Bell 1998, Kendrick et al. 2000, Fonseca et al. 2002, Krause-Jensen et 

al. 2003, Frederiksen et al. 2004) and the influence of hydrodynamics in general on 

seagrass recovery (Kirkman 1985, Kendrick et al. 2000, Whitfield et al. 2002). RWE 

categories were generalized as follows: < 10000, 10001-20000, and > 20000. The initial 
3

categorization of sites in this manner strictly served as a mechanism to achieve a 

representative subset of sites but was not used for statistical analyses Within each age x 

RWE combination, it was our desire to obtain a minimum of three representative 

grounding sites. In some instances this was not possible due to the absence or limited 

numbers of sites meeting those criteria. In the end, a total of 30 sites were selected for 

investigation. 

Initial Field Assessments

The 30 grounding sites had previously been assessed by DAC staff (typically within two 

weeks of the grounding incident) using established, quantitative techniques (Kirsch et al., 

2005). Each grounding site was mapped by physically tracing the outline of the injury 

features using DGPS. Depending upon the depth of water over the injury features, the 

DGPS unit was either handheld and the outlines traced by walking the injury perimeter or 

mounted on an inflatable boat which was then floated around the perimeter under the 

guidance of a snorkeler. Injury feature coordinates (WGS84 datum) were downloaded to 

Trimble GPS Pathfinder Office software and then exported to ESRI’s ArcView® 

software for calculation of injury area (square meters) using the UTM83 – Zone 17N

coordinate system.

Replicate 0.25m2 quadrats were haphazardly tossed into each injury feature and in the 

surrounding undisturbed seagrass meadow and the cover of vegetation was visually 

inspected. Seagrass, macroalgae, and coral present in the quadrats were identified and 

assigned a cover-abundance scale value: 0 = not present, 0.1 = solitary specimen, 0.5 = 

few specimens (< 5), 1 = numerous but no more than 5% cover, 2 = 5 to 25% cover, 3 = 

26 to 50% cover, 4 = 51 to 75% cover, and 5 = greater than 75% cover. A minimum of 

three quadrats were sampled from within each injury feature (a function of injury size) 

and a minimum of 10 from the undisturbed reference area taken within 1-3 m of the 

injury features. Care was taken to collect reference samples from around the entirety of 

the injury perimeter to account for habitat heterogeneity in the reference bed.

Revisit Field Assessments 

During the summer of 2004 and spring of 2005, each of the 30 injury grounding sites 

were revisited and reassessed duplicating the aforementioned DAC protocol. The timelapse between initial assessment and re-assessment resulted in site ages ranging from 

1.43 – 3.46 years. To quantify seagrass re-colonization (recovery) within blowholes, the 

original blowhole perimeter was uploaded into the DGPS, re-traced, and marked with 

survey flags. Braun-Blanquet quadrats were then sampled from within the original 

blowhole perimeter utilizing the same level of replication as in the initial field 

assessment. If there was a change in the perimeter of the original injury feature, a new 

injury outline was mapped by delineating the perimeter of the currently existing bare 

substrate. 
4

Natural Recovery Estimates

From the original Braun-Blanquet cover estimates at each site, the following Density (D) 

statistic was calculated for each blowhole, by seagrass species, and for total seagrass 

present:

 n

Di = ∑ Sij / n

 j=1

where Di = density of species i; j = quadrat number from 1 to n, the total number of 

quadrats sampled per injury feature; and Sij = the Braun-Blanquet score for species i in 

quadrat j (Kenworthy et al., 1993; Fourqurean et al., 2001). The Density statistic was 

used to calculate percent natural recovery of seagrass for each blowhole feature, by 

seagrass species as follows:

% Recovery = (Dir / Dic) x 100

where Dir = density of species i from reassessment samples r taken from directly within 

the original injury perimeter and Dic = density of species i from control samples c taken at 

the time of injury occurrence. Here, Dic represents the pre-injury baseline, assumed to be 

static, and thus, the final desired endpoint of restoration. 

Model Recovery Estimates

A cellular automata modeling technique was used to formulate injury recovery 

trajectories for each site (Fonseca et al., 2000b; 2004). The model used an iterative 

process whereby each iteration of the model represented a time step of one year and 

yielded a grid that continually filled with occupied cells until all cells were designated as 

being occupied. The percentage of the injury that had recovered and the remaining years 

to complete recovery were calculated at each time step for Thalassia testudinum and 

Syringodium filiforme / Halodule wrightii combined. Percent recovery was then plotted 

by time in years to derive the recovery horizon for the entire injury. The resulting 

regression equations were used to calculate the expected percent recovery for each injury 

based upon the actual age of the injury. We then compared the predicted percent 

recovery to that which was observed to be occurring naturally. 

RESULTS

All 30 sites had Thalassia testudinum present in the reference quadrats; however, we 

were unable to run the model for one site, due to discrepancies in the collection of the 

field data, therefore, N = 29. The model over-predicted T. testudinum recovery for all but 

two sites (93% of the time), with an average over-prediction difference of ~24% (Figure 

1). 

Of the 19 sites that had Syringodium filiforme present in the reference seagrass bed, the 

model over-predicted recovery 89.5% of the time (17 of 19 sites) with an average overprediction difference of ~73% (Figure 1).
5

Halodule wrightii was present in reference samples from 11 of the 29 sites. Of these 11, 

the model over-predicted recovery for 6 sites with an average over-prediction difference 

of 76.4% (Figure 3). For the remaining five sites where recovery was under-estimated, 

the difference was much more extreme with an average under –prediction difference of 

160% (Figure 1). 

Figure 1. Absolute difference between model-predicted and natural percent recovery of selected 

vessel grounding sites in Florida Keys National Marine Sanctuary. Positive differences indicate 

model over-prediction while negative differences indicate under-prediction.
6

DISCUSSION

To our knowledge, these data represent the first quantitative post-hoc validation of the 

injury recovery model currently employed by NOAA for seagrass injury 

assessment. These preliminary findings indicate that the recovery model is consistently 

generous to Responsible Parties in that the model forecasts a much faster recovery than 

was observed to occur naturally, especially for T. testudinum and S. filiforme. It was very 

important to document whether T. testudinum was being fairly assessed given that the 

inherently slow growth rate of this species contributes far more heavily to computations 

of lost interim services under HEA (Fonseca et al., 2000b). Therefore, the application of 

the cellular automata model has thus far resulted in over-estimation of the recovery rate 

and under-estimation of lost interim services resulting in lower dollar amounts in claims 

cases against the Responsible Party as well as lowered funds for restoration efforts. 

Fonseca et al. (2004) and Kirsch et al. (2005) suggested that aspects of the model would 

likely lead to over-estimation of recovery because the injured area was considered to be 

fully conducive to recovery (i.e., the sediment was level with the surrounding unimpacted seagrass; Hammerstrom et al. (2007) demonstrated that as little as 20cm of 

sediment loss could inhibit T. testudinum re-growth). Another attribute of the modeling 

approach not previously mentioned is that each injury polygon is allowed to recover with 

seagrass at all edges. In reality, many injuries have blowholes and berms adjacent to 

each other so that no seagrass recovery source is available for long portions of the injury 

edge. Additionally, the model currently does not consider the recovery of below-ground 

biomass which is often more severe than losses to the above-ground component and 

requires considerably more time to fully recover (Di Carlo and Kenworthy, 2008). 

Under-estimates of recovery for H. wrightii tended to be large when they occurred. This 

is not surprising given the opportunistic nature of this species and its capacity to rapidly 

colonize an area (Fonseca et al., 1987; Gallegos et al., 1994; Kenworthy et al., 2002; 

Uhrin et al., 2009). The rapid natural recovery rate for this species indicates that injury to 

H. wrightii beds would have comparatively low restoration costs (sensu Fonseca et al., 

2004). Primary restoration protocols in the Mini 312 Program capitalize on this 

functional characteristic of H. wrightii by prescribing the planting and fertilization of this 

species to rapidly stabilize sediments and contribute to the establishment of a functional 

seagrass habitat (“compressed succession” Derrenbacker and Lewis, 1982; Fonseca et al., 

1987; Kenworthy et al., 2000). Here, compressed succession initiates the long-term 

(decades) return of what is most often the primary shallow water seagrass species in 

FKNMS, Thalassia testudinum. 

Ongoing analysis is underway to attempt to isolate environmental factors influencing 

natural recovery of these injuries. From previous studies, the influence of site exposure to 

waves seems to indicate that the open gap created by a blowhole will increase in size with 

extreme event wave energy as seen with storm impacts to patchy seagrass and injured 

seagrass beds elsewhere (Fonseca et al., 2000a; Whitfield et al., 2002). We will continue 

to examine this response to determine whether the particular location of an injury site has 
7

a storm-related or even just ambient wave energy exposure that would influence the local 

seagrass landscape pattern (sensu Fonseca and Bell 1998) or might trigger priority 

restoration action to prevent further injury.

However, we can conclude at this point that the injury recovery modeling approach that 

has been adopted for use in the Mini-312 Program is over-estimating recovery to the 

benefit of the Responsible Party in injury cases that are dominated by T. testudinum. No 

decisions have been reached as to whether the modeling process will be revised. 

ACKNOWLEDGEMENTS

This study was funded by NOAA’s Damage Assessment Center as well as additional 

direct support from the National Centers for Coastal Ocean Science. This work would 

not have been possible without field and technical support from K. Kirsch, S. Meehan, A. 

Simonti, and A. Farrer. We also recognize M. Edson, G. DiCarlo, J. Hackney, G. Piniak, 

and J. Vander Pluym for field assistance and D. Johnson, P. Marraro, G. Piniak, M.E. 

Rolle, J. Schittone, A. Stratton, and L. Symons for comments that improved the 

manuscript.

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Zieman, J. C. 1982. The ecology of seagrasses of south Florida: a community profile.

USFWS/OBS-82/25. U. S. Department of the Interior, Fish and Wildlife Service, 

Washington, D. C. 123p.

Zieman, J. C. and R. T. Zieman. 1989. The ecology of the seagrass meadows of the west 

coast of Florida: a community profile. Biological Report 85(7.25). U. S. 

Department of the Interior, Fish and Wildlife Service, Research and 

Development, Washington, D. C. 129p.
11

NMSP CONSERVATION SERIES PUBLICATIONS

To date, the following reports have been published in the Marine Sanctuaries Conservation 

Series. All publications are available on the Office of National Marine Sanctuaries Web site 

(http://www.sanctuaries.noaa.gov/).

A Comparison of Seafloor Habitats and Associated Benthic Fauna in Areas Open and Closed to 

Bottom Trawling Along the Central California Continental Shelf (ONMS-09-02)

Chemical Contaminants, Pathogen Exposure and General Health Status of Live and Beach-Cast 

Washington Sea Otters (Enhydra lutris kenyoni) (ONMS-09-01)

Caribbean Connectivity: Implications for Marine Protected Area Management (ONMS-08-07)

Knowledge, Attitudes and Perceptions of Management Strategies and Regulations of FKNMS by 

Commercial Fishers, Dive Operators, and Environmental Group Members: A Baseline 

Characterization and 10-year Comparison 

(ONMS-08-06)

First Biennial Ocean Climate Summit: Finding Solutions for San Francisco Bay Area's Coast and 

Ocean 

(ONMS-08-05)

A Scientific Forum on the Gulf of Mexico: The Islands in the Stream Concept (NMSP-08-04)

M/V ELPIS Coral Reef Restoration Monitoring Report Monitoring Events 2004-2007 Florida 

Keys National Marine Sanctuary Monroe County, Florida (NMSP-08-03)

CONNECTIVITY Science, People and Policy in the Florida Keys National Marine Sanctuary 

(NMSP-08-02) 

M/V ALEC OWEN MAITLAND Coral Reef Restoration Monitoring Report Monitoring Events 

2004-2007 Florida Keys National Marine Sanctuary Monroe County, Florida (NMSP-08-01) 

Automated, objective texture segmentation of multibeam echosounder data - Seafloor survey and 

substrate maps from James Island to Ozette Lake, Washington Outer Coast. (NMSP-07-05) 

Observations of Deep Coral and Sponge Assemblages in Olympic Coast National Marine 

Sanctuary, Washington (NMSP-07-04) 

A Bioregional Classification of the Continental Shelf of Northeastern North America for 

Conservation Analysis and Planning Based on Representation (NMSP-07-03) 

M/V WELLWOOD Coral Reef Restoration Monitoring Report Monitoring Events 2004-2006 

Florida Keys National Marine Sanctuary Monroe County, Florida (NMSP-07-02) 

Survey report of NOAA Ship McArthur II cruises AR-04-04, AR-05-05 and AR-06-03: Habitat 

classification of side scan sonar imagery in support of deep-sea coral/sponge explorations at the 

Olympic Coast National Marine Sanctuary (NMSP-07-01) 

2002 - 03 Florida Keys National Marine Sanctuary Science Report: An Ecosystem Report Card 

After Five Years of Marine Zoning (NMSP-06-12) 
12

Habitat Mapping Effort at the Olympic Coast National Marine Sanctuary - Current Status and 

Future Needs (NMSP-06-11) 

M/V CONNECTED Coral Reef Restoration Monitoring Report Monitoring Events 2004-2005 

Florida Keys National Marine Sanctuary Monroe County, Florida (NMSP-06-010) 

M/V JACQUELYN L Coral Reef Restoration Monitoring Report Monitoring Events 2004-2005 

Florida Keys National Marine Sanctuary Monroe County, Florida (NMSP-06-09)

M/V WAVE WALKER Coral Reef Restoration Baseline Monitoring Report - 2004 Florida Keys 

National Marine Sanctuary Monroe County, Florida (NMSP-06-08) 

Olympic Coast National Marine Sanctuary Habitat Mapping: Survey report and classification of 

side scan sonar data from surveys HMPR-114-2004-02 and HMPR-116-2005-01 (NMSP-06-07) 

A Pilot Study of Hogfish (Lachnolaimus maximus Walbaum 1792) Movement in the Conch Reef 

Research Only Area (Northern Florida Keys) (NMSP-06-06) 

Comments on Hydrographic and Topographic LIDAR Acquisition and Merging with Multibeam 

Sounding Data Acquired in the Olympic Coast National Marine Sanctuary (ONMS-06-05) 

Conservation Science in NOAA's National Marine Sanctuaries: Description and Recent 

Accomplishments (ONMS-06-04)

Normalization and characterization of multibeam backscatter: Koitlah Point to Point of the 

Arches, Olympic Coast National Marine Sanctuary - Survey HMPR-115-2004-03 (ONMS-06-03) 

Developing Alternatives for Optimal Representation of Seafloor Habitats and Associated 

Communities in Stellwagen Bank National Marine Sanctuary (ONMS-06-02) 

Benthic Habitat Mapping in the Olympic Coast National Marine Sanctuary (ONMS-06-01) 

Channel Islands Deep Water Monitoring Plan Development Workshop Report (ONMS-05-05) 

Movement of yellowtail snapper (Ocyurus chrysurus Block 1790) and black grouper 

(Mycteroperca bonaci Poey 1860) in the northern Florida Keys National Marine Sanctuary as 

determined by acoustic telemetry (MSD-05-4) 

The Impacts of Coastal Protection Structures in California's Monterey Bay National Marine 

Sanctuary (MSD-05-3) 

An annotated bibliography of diet studies of fish of the southeast United States and Gray's Reef 

National Marine Sanctuary (MSD-05-2) 

Noise Levels and Sources in the Stellwagen Bank National Marine Sanctuary and the St. 

Lawrence River Estuary (MSD-05-1) 

Biogeographic Analysis of the Tortugas Ecological Reserve (MSD-04-1) 
13

A Review of the Ecological Effectiveness of Subtidal Marine Reserves in Central California 

(MSD-04-2, MSD-04-3) 

Pre-Construction Coral Survey of the M/V Wellwood Grounding Site (MSD-03-1) 

Olympic Coast National Marine Sanctuary: Proceedings of the 1998 Research Workshop, Seattle, 

Washington (MSD-01-04) 

Workshop on Marine Mammal Research & Monitoring in the National Marine Sanctuaries 

(MSD-01-03) 

A Review of Marine Zones in the Monterey Bay National Marine Sanctuary (MSD-01-2) 

Distribution and Sighting Frequency of Reef Fishes in the Florida Keys National Marine 

Sanctuary (MSD-01-1) 

Flower Garden Banks National Marine Sanctuary: A Rapid Assessment of Coral, Fish, and Algae 

Using the AGRRA Protocol (MSD-00-3) 

The Economic Contribution of Whalewatching to Regional Economies: Perspectives From Two 

National Marine Sanctuaries (MSD-00-2) 

Olympic Coast National Marine Sanctuary Area to be Avoided Education and Monitoring 

Program (MSD-00-1) 

Multi-species and Multi-interest Management: an Ecosystem Approach to Market Squid (Loligo 

opalescens) Harvest in California (MSD-99-1)