boem.gov | 1
2020 boem.gov | 2 ATLANTIC SCIENCE 

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Overview

The Bureau of Ocean Energy Management (BOEM) 

funds environmental studies for information 

needed to predict, assess, and manage impacts 

from offshore energy and marine mineral activities 

on human, marine, and coastal environments 

as mandated under Section 20 of the Outer 

Continental Shelf Lands Act.

This year in review presents the studies completed 

in 2020 in support of BOEM’s Offshore Renewable 

Energy Program along the Atlantic Coast. The 

studies represent a broad spectrum of research and 

monitoring to address a variety of environmental 

concerns and issues. Topics in this review include 

methods for tracking birds and fish, modeling pile 

driving, and paleolandforms and methodologies 

for identifying submerged cultural sites. This 

review represents a snapshot of the ongoing and 

completed studies funded in whole or in part by 

BOEM.

A special issue of Oceanography—”Understanding 

the Effects of Offshore Wind Development on 

Fisheries”—was published in December of 2020. 

The issue provides an overview of what has been 

learned from research and monitoring of offshore 

wind farm impacts on fisheries resources based on 

the European experience. 

To learn more about other studies, please visit the 

BOEM website at www.boem.gov.

Images | (cover) releasing tagged piping plover, courtesy of Peter 

Paton | (top) Endeavor coring cruise | (middle) measuring the 

width of a crab | (bottom) stern section of City of Houston with 

potential rudder post remains
2020 boem.gov | 3 ATLANTIC SCIENCE 

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BIRDS 

4 Assessing Movements of Birds Using Digital 

VHF Transmitters: A Validation Study

5 Tracking Movements of Migratory 

Shorebirds in the U.S. Atlantic Outer 

Continental Shelf Region

CULTURAL RESOURCES

6 Developing Protocols for Reconstructing 

Submerged Paleocultural Landscapes 

and Identifying Ancient Native American 

Archaeological Sites in Submerged 

Environment

7 North Carolina Collaborative Archaeological 

Survey: Wilmington East and West Wind 

Energy Areas

FATES AND EFFECTS

8 A Parametric Analysis and Sensitivity Study 

of the Acoustic Propagation for Renewable 

Energy

9 Radar Interference Analysis for Renewable 

Energy Facilities on the Atlantic Outer 

Continental Shelf

10 Movement and Habitat Selection by 

Migratory Fishes Within the Maryland Wind 

Energy Area and Adjacent Reference Sites

Table of Contents

FISH AND FISHERIES

11 Occurrence of Commercially Important and 

Endangered Fishes in Delaware Wind Energy 

Areas Using Acoustic Telemetry

12 Spatial and Temporal Distributions of 

Lobsters and Crabs in the Rhode Island/

Massachusetts Wind Energy Area

RODEO

13 RODEO: Realtime Opportunity for 

Development Environmental Observations

14 Benthic Monitoring During Wind Turbine 

Installation and Operation at the Block 

Island Wind Farm, Rhode Island 

15 Seafloor Disturbance and Recovery 

Monitoring at the Block Island Wind Farm, 

Rhode Island

16 What’s Next
boem.gov | 4

Assessing Movements 

of Birds Using Digital 

VHF Transmitters: 

A Validation Study

Conducted by: University of Rhode Island and US 

Fish and Wildlife Service

Key researchers: P. Paton, C. Cooper-Mullin, S. 

Kouhi, P. Loring, J. Moore, J. Miller, G. Potty

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Developing methodologies to measure interactions 

between birds and offshore wind turbines is a focal 

area for BOEM. This study evaluated automated 

radio telemetry technology and modeling methods 

to assess bird movements at Block Island Wind 

Farm (BIWF). One of the primary goals of this study 

was to conduct a series of calibration surveys 

to assess the detection probability of receiving 

stations with different configurations of antennas 

to track the offshore movements of digitally 

coded VHF (Very High Frequency) transmitters. 

Automated radio telemetry stations tracked 

movements of three focal species—common terns, 

roseate terns, and piping plovers—in the vicinity of 

BIWF from 2017–2019. Tracking stations on Block 

Island detected a total of 157 unique tags from 

15 species, including the 3 focal species, 6 species 

of shorebirds, and 6 species of passerines. Of the 

three focal species tagged at breeding areas in 

coastal Rhode Island, Connecticut, and New York, 

79% of the common terns, 24% of the roseate 

terns, and 33% of the piping plovers moving past 

Block Island were detected. 

Findings

• Using digital VHF transmitters can provide useful 

information on macroscale offshore movements 

of birds.

• VHF tracking technology has difficulties tracking 

fine scale temporal and spatial movements of 

small birds such as passerines.

How BOEM will use this information

• Develop methodologies to track avian species in 

and around wind facilities after construction

• Identify mitigation measures to reduce 

interactions of birds with wind turbines 

Additional information

Final report: https://espis.boem.gov/final%

20reports/BOEM_2021-009.pdf

Images | (left) tagged plover | (center) drone testing near turbine 

at Block Island Wind Farm | (right) releasing a tagged plover

All photos courtesy of Peter Paton, URI

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW
boem.gov | 5

Tracking Movements 

of Migratory 

Shorebirds in the 

U.S. Atlantic Outer 

Continental Shelf 

Region

Conducted by: US Fish and Wildlife Service

Key researchers: P. Loring, A. Lenske, J. McLaren, 

M. Aikens, A. Anderson, Y. Aubry, E. Dalton, A. Dey, 

C. Friis, D. Hamilton, et al.

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Numerous researchers across the continents are 

tagging birds for scientific research purposes. In 

this study, movement data was compiled from 

3,955 individuals of 17 shorebird species tagged 

with digital VHF (very high frequency) transmitters 

at 21 sites across North and South America 

between 2014 and 2017. The movements of tagged 

shorebirds were tracked using a collaborative radio 

telemetry network, the Motus Wildlife Tracking 

System globe (http://motus-wts.org/). The study 

area encompassed a region of the US Atlantic 

Coast extending from Cape Cod, Massachusetts, to 

Back Bay, Virginia, and had extensive coverage of 

radio telemetry receiving stations. Movements and 

flight altitudes of 594 individuals of 12 shorebird 

species were identified to have sufficient detection 

data within the study area. The array of land-based 

automated radio telemetry stations was limited 

to assessing the flight paths and behavior of 

departing shorebirds within 20 km off the coast.

Findings

• Most model-estimated flight altitudes were 

estimated to occur above the Rotor Swept Zone 

(RSZ) of offshore wind turbines (25–250 m). 

• Exposure to the RSZ was higher during fall 

relative to spring. 

• Across all species, offshore flights during fall 

were associated with fair weather conditions.

How BOEM will use this information

• Incorporate the findings in environmental 

assessments

• Design future tracking studies of birds 

Additional information

Final report: https://www.boem.gov/sites/default/

files/documents/renewable-energy/studies/

Tracking-Migratory-Shorebirds-Atlantic-OCS.pdf

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) constructing tower | (center) locations of shorebird 

tagging sites | (right) digital VHF transmitter mounted on red 

knot, photo courtesy Kaiti Tithertington USFWS 
boem.gov | 6

Developing Protocols 

for Reconstructing 

Submerged Paleocultural 

Landscapes and 

Identifying Ancient 

Native American 

Archaeological Sites in 

Submerged Environment

Conducted by: University of Rhode Island

Key researchers: J. King, D. Robinson, C. Gibson, B. 

Caccioppoli

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Considering the effects offshore energy development may have on submerged historic properties—

including Native American cultural sites submerged 

by post-glacial sea level rise and now underwater 

on the continental shelf—is a significant concern 

for individual states, Tribes, other regulatory agencies, stakeholders, and researchers participating in 

environmental review and consultation for offshore 

development projects. The project was conducted 

in 2012 to 2019 by the University of Rhode Island 

Graduate School of Oceanography (URI-GSO), 

Rhode Island Coastal Resource Management Council, and Narragansett Indian Tribal Historic Preservation Office. The study involved the multidisciplinary 

investigation of five nearshore and offshore areas 

in Rhode Island waters. A series of workshops and 

field activities helped develop a clearly defined, 

standardized methodology to identify submerged 

areas of cultural significance to contemporary Tribal 

people. This project completed eight interrelated 

tasks and deliverables in collaboration with URIGSO’s project partners and with the input and assistance of multiple federally and state-recognized 

Tribes, Federal and state agencies, industry, and 

regional and international academic institutions.

Findings

• Identification of submerged land areas is 

challenging in the marine environment.

• Continued engagement with Tribes is critical to a 

successful process.

How BOEM will use this information

• Assist with the development of effective, 

culturally sensitive collaboration and 

consultation as part of the National Historic 

Preservation Act (NHPA) Section 106 compliance 

process

Additional information

• Summary report of the initial project workshop

• Field Report: 2013–2016

• Best Practices

• Geoarchaeological Modeling

• Final Report

• Project Video

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) researchers at Block Island, RI | (center) USGS 

stratigraphic framework ot the subsurface continental shelf off 

Rhode Island | (right) diver looking at submerged stump
boem.gov | 7

North Carolina 

Collaborative 

Archaeological Survey: 

Wilmington East and 

West Wind Energy 

Areas

Conducted by: Bureau of Ocean Energy 

Management (BOEM) and National Oceanic and 

Atmospheric Administration (NOAA) Monitor 

National Marine Sanctuary

Key researchers: W. Hoffman, J. Hoyt, W. 

Sassorossi

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Baseline archaeological data within wind energy 

areas is needed to minimize impacts to important 

archaeological sites on the Outer Continental 

Shelf. This study obtained baseline archaeological 

information in and around the Wilmington East 

and West Wind Energy Areas by ground truthing, 

via diver-based investigation, selected targets of 

archaeological potential. This project leveraged 

the results of reconnaissance-level geophysical 

survey conducted under BOEM studies in the 

region identifying potential archaeological targets 

warranting further investigation. Eight potential 

archaeological sites were investigated representing 

a broad range of cultural resources spanning from 

the late-nineteenth century through World War II, 

highlighting the diversity of potential resources 

likely present offshore North and South Carolina. 

Findings

• Five of the eight targets investigated were 

confirmed to be archaeological sites, and the 

study recommended avoidance buffers and 

additional investigation for these sites. 

• The remaining three targets were determined to 

not warrant further investigation. 

How BOEM will use this information

• Reduce the impact of wind energy development 

on archaeological sites by identifying their 

location and providing a zone for avoidance

• Assist BOEM in considering the effects of 

its activities on cultural resources under the 

National Historic Preservation Act and National 

Environmental Policy Act

Additional information

• Final report: https://espis.boem.gov/final%20

reports/BOEM_2020-016.pdf

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) batteries located on port side of site of 6537K_1 | 

(center) City of Houston (Wrecksite 2007) | (right) copper 

Cookware exposed at site of 6537K_1
boem.gov | 8

A Parametric Analysis 

and Sensitivity Study 

of the Acoustic 

Propagation for 

Renewable Energy

Conducted by: CSA Ocean Sciences Inc.

Key researchers: K. Heaney, M. Ainslie, M. 

Halvorsen, K. Seger, R. Müller, M. Nijhof, T. Lippert 

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Findings

• Additional modeling is need, if a pile site 

differs by more than 50% in depth, consists of 

more than 1 φ in grain size, is installed during 

different seasons, or occurs at intervals of 15 km 

farther away or closer to shore.

• New models should be generated during the 

month of proposed activity to understand how 

sound may travel through the environment.

How BOEM will use this information

• Evaluate the impacts from pile driving

• Inform review of modeling results provided by 

offshore wind developers

Additional information

• Final report: https://espis.boem.gov/final%20

reports/BOEM_2020-011.pdf 

Sound generated during pile driving may be a 

significant source of potential impacts to marine 

life from offshore wind development. This study 

examined the parameters that affect the results of 

sound modeling for monopile wind turbines. The 

key parameters include water depth, sediment type, 

and water column temperature. The contractor 

developed a new model for pile driving noise and 

calibrated the model using measurements from 

pile driving events in Europe. The product is a 

spreadsheet that generate the sound exposure for 

fish, sea turtles, and marine mammals by entering 

simple parameters such as water depth and 

monopile diameter. The modeled sound exposure 

is then compared to National Marine Fisheries 

Service prescribed levels for injury and harassment. 

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) plan view of sound field off Rhode Island | (center) 

map of Rhode Island and Virginia Beach sites | (right) plan view of 

sound fields off the coast of Virginia
boem.gov | 9

Radar Interference 

Analysis for Renewable 

Energy Facilities on 

the Atlantic Outer 

Continental Shelf

Conducted by: Booz Allen Hamilton

Key researchers: R. Colburn, C. Randolph, C. 

Drummond, M. Miles, F. Brody, C. McGillen, A. 

Krieger, R. Jankowski

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Findings

• Wind farms are within line of site of 36 radar 

systems, indicating that they will generate 

interference to these radars under normal 

atmospheric conditions.

• Mitigation may be possible through software 

upgrades.

How BOEM will use this information

• Evaluate the impacts of wind turbines on radar 

systems

• Develop mitigation measures for the interference

Additional information

• Final report: https://www.boem.gov/sites/

default/files/documents/environment/RadarInterferance-Atlantic-Offshore-Wind_0.pdf

The presence of wind energy installations is known 

to impact land-based radar systems as wind 

turbines consist of large metal structures that can 

generate a return signal to radars. Radar signals 

generated by objects other than the intended 

targets (e.g., the ground, artificial structures, 

wind turbines) are referred to as “clutter” or 

“interference,” and represent a potential impact to 

be investigated under the National Environmental 

Policy Act. This study investigates land-based 

radar interference impacts on nine total wind 

farms, seven of which were in planning stages, and 

two of which were based on hypothetical future 

scenarios. The radar type with the most radars 

affected was the SeaSonde, reflecting the large 

number of SeaSondes along the Atlantic Coast. The 

research team also qualitatively ranked the severity 

of impacts caused by each wind farm. Skipjack, 

South Fork, and Grand Strand were found to have 

low radar impacts. Mayflower, Vineyard Wind, Bay 

State Wind, and Ocean Wind were found to have 

moderate impacts, and Empire Wind was found to 

have higher impacts.

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) proposed and hypothetical wind farm locations | 

(center) SeaSonde® high frequency radar system in view of wind 

turbines | (right) line of sight modelling
boem.gov | 10

Movement and 

Habitat Selection 

by Migratory Fishes 

Within the Maryland 

Wind Energy Area and 

Adjacent Reference 

Sites

Conducted by: University of Maryland Center for 

Environmental Science

Key researchers: D. Secor, M. O’Brien, E. 

Rothermel, C. Wiernicki, H. Bailey

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Findings

• Detections of Atlantic sturgeon occurred in 

autumn, early winter, spring, and early summer.

• Striped bass occurrence was more concentrated 

during winter months, with a rapid pulse in 

spring. 

• Both species moved through the study area 

in an average of 1.6 and 2.5 days for Atlantic 

sturgeon and striped bass, respectively.

• Single-variable analyses and habitat models 

alike identified depth and temperature as key 

variables; Atlantic sturgeon tended to occur at 

shallower sites and warmer temperatures while 

striped bass were more likely at great depths 

and cooler conditions.

How BOEM will use this information

• Design future post-construction telemetry 

studies of fish

• Provide baseline information for environmental 

assessments of future offshore wind 

development

Additional information

• Final report: https://espis.boem.gov/final%20

reports/BOEM_2020-030.pdf

Seasonal transit and habitat occurrence of striped 

bass and Atlantic sturgeon in offshore wind energy 

areas are important baseline information needed 

to assess potential impacts to these species from 

offshore wind energy development. Biotelemetry 

was used in a before after-gradient design centered 

in the Maryland Wind Energy Area to measure 

seasonal patterns of migration by Atlantic sturgeon 

and striped bass. Models were used to relate these 

patterns to gradients of depth, temperature, and 

other oceanographic variables. Acoustically tagged 

striped bass and Atlantic sturgeon were monitored 

with an extensive telemetry receiver array. From 

November 2016–December 2018, the array logged 

745,385 detections of 1,286 acoustically tagged 

fish, most of which were target species of the study: 

striped bass (315 individuals) and Atlantic sturgeon 

(352 individuals). An additional 18 species were 

identified, including Atlantic cod; Atlantic bluefin 

tuna; black sea bass; blacktip, bull, dusky, sand 

tiger, tiger, and white sharks; and cownose ray.

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left & right) Maryland research team in the field |

(center) Atlantic sturgeon hot spots in Maryland wind energy area
boem.gov | 11

Occurrence of 

Commercially 

Important and 

Endangered Fishes in 

Delaware Wind Energy 

Areas Using Acoustic 

Telemetry

Conducted by: University of Delaware and 

Delaware State University

Key researchers: D. Haulsee, M.J. Oliver, D. Fox

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Findings

• Atlantic sturgeon were observed during all 

months of the period but occurred most 

frequently in the late fall/early winter. 

• Atlantic sturgeon were also most concentrated 

in the northern portion of the study region, 

except in the late fall/early winter, when they 

were detected throughout the entire array. 

• Winter skate occurred less commonly and were 

concentrated in the shallowest portion of the 

study region. 

• Both species appear to be related to bottom 

type and topography, which is most distinctive 

in the northern portion of the Delaware Wind 

Energy Area.

How BOEM will use this information

• Baseline information for environmental 

assessments of offshore wind development

• Improve future post-construction telemetry 

studies of fish

Additional information

• Final report: https://espis.boem.gov/final%20

reports/BOEM_2020-020.pdf

Prior to offshore wind development, baseline 

information is needed on endangered species such 

as the Atlantic sturgeon. Between 2017–2019, an 

extensive acoustic telemetry project monitored 

the timing and location of Atlantic sturgeon, 

winter skate, and other acoustically telemetered 

species in the Delaware Wind Energy Area. This 

study was conducted to better understand the 

potential of encountering these species during 

future development in the area, as well as address 

potential impacts to commercial fisheries (e.g., 

winter skate). Environmentally driven models of 

Atlantic sturgeon and winter skate were developed. 

Between Feb 2017 and Feb 2019, receivers 

recorded 43,620 detections of 360 individual 

Atlantic sturgeon. Acoustic detections from all 

receivers in the array documented the presence 

of 26 different marine fish and mammals, which 

creates a baseline to inform future monitoring 

efforts.

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) collecting metadata for Atlantic sturgeon | (center) 

map of study area and telemetry stations | (right) collecting 

metadata for Winter skate
boem.gov | 12

Spatial and Temporal 

Distributions of 

Lobsters and Crabs 

in the Rhode Island/

Massachusetts Wind 

Energy Area

Conducted by: University of Rhode Island

Key researchers: J. Collie, A.M. Mercer, C. Glass, M. 

Long, J. Langan

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Findings

• The study sampled 26,449 lobsters and 95,859 

Jonah crabs.

• Seasonally, lobster abundance was highest in 

summer, and Jonah crab abundance was highest 

in summer and fall. 

• Spatially, lobster abundance was highest in the 

eastern lease blocks characterized by boulders 

and the transition from boulders to sand. 

• Jonah crab abundance was highest in the 

northern and central lease blocks, which are 

characterized by soft sediments and sand.

How BOEM will use this information

• Establish a baseline to assess the potential 

effects of offshore wind energy development

• Inform future designs for post-construction 

monitoring 

Additional information

• Final report: https://espis.boem.gov/final%20

reports/BOEM_2021-010.pdf

The Southern New England Cooperative Ventless 

Trap Survey (SNECVTS) was developed to provide 

a baseline assessment of the lobster and crab 

populations in the Rhode Island/Massachusetts 

Wind Energy Area prior to offshore wind energy 

development in southern New England. This 

study reports on a one-year continuation of 

SNECVTS, which was originally conducted in 

2014–2015. The survey was designed to contribute 

to the assessment of the Southern New England 

lobster stock, which is currently at a low level 

of abundance. To the extent possible, this 

project followed Atlantic Marine States Fisheries 

Commission survey protocols and adhered to the 

Atlantic Coastal Cooperative Statistics Program 

data requirements. Over the course of three years, 

a total of 11,990 trap hauls were sampled.

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) sampling gear | (center) lobster abundance by year 

and sampled aliquot | (right) tagged lobster
boem.gov | 13

RODEO: Realtime 

Opportunity for 

Development 

Environmental 

Observations

The Block Island Wind Farm (BIWF) is the first 

facility to be monitored under the RODEO study. 

Observations were made during the installation of 

the wind turbine foundations, the installation of the 

turbines, and early operations. The following pages 

present results from two studies that monitored 

the seafloor recovery after disturbance from 

construction activities and alterations in benthic 

macrofaunal community characteristics caused by 

the presence of structures at the BIWF.

You can find all of the RODEO reports on a 

dedicated website: www.boem.gov/rodeo

The purpose of the study Realtime Opportunity 

for Development Environmental Observations is to 

make direct, real-time measurements of the nature, 

intensity, and duration of potential stressors during 

the construction and initial operations of selected 

proposed offshore wind facilities. The purpose 

also includes recording direct observations during 

the testing of different types of equipment that 

may be used during future offshore development 

to measure or monitor activities and their impact 

producing factors.

Data collected under RODEO may be used as input 

to analyses or models that are used to evaluate 

effects from future offshore activities. This study 

is not intended to duplicate or substitute for any 

monitoring that may otherwise be required to 

be conducted by the developers of the proposed 

projects. Also, RODEO monitoring is coordinated 

with the industry and is not intended to interfere 

with or result in delay of industry activities.

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) seafloor disturbance features | 

(right) Block Island Wind Farm
boem.gov | 14

Benthic Monitoring 

During Wind Turbine 

Installation and 

Operation at the Block 

Island Wind Farm, 

Rhode Island 

Conducted by: HDR

Key researchers: Z. Hutchison, M. LaFrance Bartley, 

P. English, J. King, S. Grace, B. Kresning, C. Baxter, K. 

Ampela, M. Deakos, A. Khan

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Benthic and epifouling monitoring was conducted 

within the Block Island Wind Farm (BIWF) project 

area over four years (2016 to 2019) after turbine 

installation. Seafloor samples were collected at 

Turbines 1, 3, and 5 using a grab sampler deployed 

from a ship and analyzed for marine life, sediment 

type, and carbon content. Divers collected samples 

within the foundation structure during the last 

two years. Video transects of the legs were also 

conducted by divers. Additionally, a floating camera 

observed the seafloor near the platform legs.

Findings

• Submerged sections of the BIWF jacket 

foundation structures were completely encrusted 

by mussels (Mytilus edulis) and associated 

species.

• Significant modification of the seabed occurred 

within the footprint of the turbine foundations, 

with the area underneath Turbine 1 exhibiting 

the fastest rate of change.

• An increase in abundance of black sea bass 

(Centropristis stiata) around the foundations was 

observed between Years 2 and 3. 

• Benthic habitat four years after installation 

remain localized, with a profound change from 

a sandy habitat to a habitat characterized by 

mussel aggregations with associated organic 

matter, sediment fines, and macrofaunal 

communities.

How BOEM will use this information

• To understand of changes to macrofaunal and 

sediment characteristics resulting from wind 

facility construction and initial operations in the 

New England region over short time scales

• To extrapolation to larger wind facilities and 

provide useful information on the effects of 

jacket type foundations, which are generally 

underrepresented in European studies

Additional information

• Final report: https://espis.boem.gov/final%20

reports/BOEM_2020-044.pdf

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) species at the structure foundations at Block Island 

Wind Farm | (right) benthic sampling at Block Island Wind Farm
boem.gov | 15

Seafloor Disturbance 

and Recovery 

Monitoring at the 

Block Island Wind 

Farm, Rhode Island

Conducted by: HDR

Key researchers: A. Khan, K. Smith

Funded by: Bureau of Ocean Energy Management 

(BOEM) 

Findings

• A relatively small area of the seafloor off Block 

Island was disturbed by wind farm construction 

activities.

• Much of the disturbed area fully recovered 

within a relatively short time (1–2 years), after 

which no clear sign of any disturbance was 

evident as indicated by interpretation of the 

survey data. 

How BOEM will use this information

• Improve the evaluation of the duration of 

seafloor impacts from offshore wind foundation 

installation

• To extrapolate to larger wind facilities and 

provide useful information on the effects of 

jacket type foundations which are generally 

underrepresented in European studies

Additional information

• Final report: https://espis.boem.gov/final%20

reports/BOEM_2020-019.pdf

Seafloor disturbance and recovery monitoring was 

conducted in and around the Block Island Wind 

Farm (BIWF) to assess the impact of wind farm 

construction activities on the seafloor. Previous 

studies from Europe have shown that introduction 

of solid structures onto the seafloor, such as the 

four-legged BIWF turbine jacket foundations, can 

modify near-bottom current flow processes and 

induce scour. Five rounds of seafloor bathymetry 

surveys were conducted within a defined 

construction work area from a small research vessel 

using a Reson SeaBat 7125 ultra-high resolution 

multibeam echosounder. Seafloor bathymetry 

data from the first and second surveys were used 

primarily to characterize the different types of 

seafloor disturbance features that resulted from 

construction activities. Data from the three rounds 

of post-construction surveys were used to evaluate 

the rate of seafloor recovery.

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Images | (left) study area | (center) seafloor frame | (right) time 

series of seafloor disturbance at Block Island Wind Farm
boem.gov | 16

What’s Next

Working with NOAA, BOEM is funding broad scale 

surveys for the presence of marine mammals 

and sea turtles. This work also includes the use of 

passive acoustic monitoring to listen for whale 

calls. Researchers tagged loggerhead sea turtles 

and tracked their movements. All these efforts are 

part of the second five-year study called Atlantic 

Marine Assessment Program of Protected Species 

(AMAPPS).

Expected completion: 2021

2020 ATLANTIC SCIENCE 

YEAR IN REVIEW

Pile driving of monopile foundations during 

the installation of offshore wind turbines creates 

significant noise in the environment. The sound 

can be reduced by the use of bubble curtains. 

During the installation of the two turbines off the 

coast of Virginia, a bubble curtain was used for the 

installation of one foundation and not used for the 

other. The sound was measured during both events 

allowing for a comparison of the noise generated.

Expected completion: 2021

Here are a few of the new and continuing studies 

that are underway:

Teaming with NOAA and Woods Hole 

Oceanographic Institution, BOEM is funding a study 

to examine the response to impulsive sounds like 

pile driving. Using sound recordings representing 

pile driving, black sea bass and longfin squid

were exposed within a large tank. The behavioral 

responses were observed before, during and after 

exposure to the sound. Squid exhibited a startle 

response to the sound.

Expected completion: 2021