Real-time whale detections

A real-time detection system for whales was deployed in the Maryland Wind Energy Area, approximately 23 miles from the coast of Ocean City, Maryland, in March 2021. The project is led by Helen Bailey at UMCES in collaboration with  Mark Baumgartner at Woods Hole Oceanographic Institution. Different whale species make different sounds that are detected by an underwater microphone, processed, and transmitted from a surface buoy at sea to scientists on shore via satellite. Click here to see the whales that have been detected along the Atlantic coast.

Baseline acoustic monitoring for marine mammals

As the focus of renewable energy in the United States turns to offshore wind facility development, there is an increasing need for an understanding of potential noise impacts from this development on marine mammals. Pile-driving of offshore wind turbines produces loud, low-frequency sound that can travel great distances and could potentially harm or disturb marine mammals. A critical first step is to understand the current baseline ambient noise levels and the spatiotemporal distribution of marine species that could potentially be impacted.

Helen Bailey led a team consisting of researchers at UMCES’ Chesapeake Biological Laboratory and with Aaron Rice at the Center for Conservation Bioacoustics, Cornell University, that collected three years of baseline data during November 2014-2017 within and surrounding the Maryland Wind Energy Area prior to construction of an offshore wind energy facility. Click here to see the two-page summary.

Key findings of this study were:

  • Baleen whales (North Atlantic right whale, fin, humpback and minke whale) were mainly detected during the November to May timeframe. 

  • Fin whales were the most frequently detected baleen whale species, but detections were most common offshore of the WEA. 

  • Humpback whales mainly occurred within and offshore of the WEA. Minke whales were only occasionally detected within our passive acoustic array. 

  • North Atlantic right whales were detected during every month of the year, but were most common during the November to April timeframe. 

  • Localized North Atlantic right whale calls indicated they migrated through and offshore of the Maryland WEA. 

  • Bottlenose dolphins were frequently detected year-round within and inshore of the WEA, except in February, whereas offshore sightings were limited to summer and fall. Common dolphins were detected offshore of the WEA from December to May. Within the Maryland WEA, a minimum of 700 individual bottlenose dolphins occurred within the detection range of our acoustic recorders during Summer 2016 to Summer 2017 based on analysis of their signature whistle calls. 

  • Harbor porpoises were detected from November to June with the peak between January and May. During the first year of the study harbor porpoises were most common within and offshore of the WEA, whereas in the second and third years they were detected more commonly within and inshore of the WEA. 

  • Sites along the eastern edge and offshore of the WEA had the loudest ambient noise levels, particularly within low frequency bands, suggesting shipping noise is a major contributor to the noise environment. 

  • Elevated ambient noise levels were associated with higher dolphin whistle frequencies and a less complex whistle contour. 

Summary of the findings                    Download the full report

The Maryland Department of Natural Resources is working with the Maryland Energy Administration and BOEM to support baseline ecological studies off the Maryland coast and in the proposed wind energy areas.


Bailey, H., Lyubchich, V., Wingfield, J., Fandel, A., Garrod, A., and Rice, A.N. (2019) Empirical evidence that large marine predator foraging behavior is consistent with area-restricted search theory. Ecology, 100: e02743.

Garrod, A., Fandel, A. D., Wingfield, J. E., Fouda, L., Rice, A. N., and Bailey, H. (2018) Validating automated click detector dolphin detection rates and investigating factors affecting performance. The Journal of the Acoustical Society of America, 144: 931-939.

Fouda, L., Wingfield, J. E., Fandel, A. D., Garrod, A., Hodge, K. B., Rice, A. N., and Bailey, H. (2018) Dolphins simplify their vocal calls in response to increased ambient noise. Biology letters, 14: 20180484.

Wingfield, J.E., O’Brien, M., Lyubchich, V., Roberts, J.J., Halpin, P.N., Rice, A.N. and Bailey, H. (2017) Year-round spatiotemporal distribution of harbour porpoises within and around the Maryland wind energy area. PLoS ONE, 12: e0176653.

Bailey, H., Brookes, K.L. and Thompson, P.M. (2014) Assessing environmental impacts of offshore wind farms: Lessons learned and recommendations for the future. Aquatic Biosystems, 10: 8.

Sjollema, A. L., Gates, J.E.,  Hilderbrand, R.H. and Sherwell, J. (2014) Offshore activity of bats along the Mid-Atlantic Coast. Northeastern Naturalist 21: 154-163.