#1WARNER COLLEGE OF Natural Resources Colorado State University Park National Natural Sou Sounds Service Night Skies NATIONAL PARK SERVICE ווי Discovering patterns of biological and anthropogenic activity at National Park of American Samoa using underwater acoustical monitoring Abigail L Crowder¹, Jacob R Job 1,3, Timothy Clark², Megan F Mckenna³ 1 Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO 80523 2 National Park Service, National Park of American Samoa, Pago Pago, AS 96799 3 National Park Service, Natural Sounds and Night Skies Division, Fort Collins, CO 80525 Colorado State University Objectives What are the acoustical conditions of the National Park of American Samoa's marine environment? • What are the sources of biological sounds? • What are the sources of human-associated noise? • What are the patterns of presence of biological sounds and human-associated noise? Introduction The acoustical environment of a place can tell us a lot about the health of an ecosystem. Acoustical monitoring is a non-invasive and effective method of characterizing both terrestrial and marine ecosystems. Acoustical monitoring can provide insight into the presence and occurrence of species living or migrating through a region, ecological processes, and levels of human activity. Long-term acoustical monitoring can provide important insight into changes to ecosystems, as well as provide guidance for management decisions. National Park of American Samoa is part of the first large-scale effort to monitor long-term trends of underwater acoustical environments across U.S. waters. Methods 0 Number of Calls 50 100 150 200 250 300 350 Results 2.40- 2.30- Daily Fish Calling 2.20- 2.10- 2.00- 1.90- 1.80- 1.70- 1.60- 1.50- 1.40- 1.30- 1.20- 1.10- 1.00- 0.90- 0.80- 0.70- 0.60- 0.50- 0.40- 0.30- 0.20- 0.00 kHz, "h:m:s 1:18:18 1:18:25 1:18:30 1:18:35 1:18:40 1:18:45 1:18:50 1:18:55 1:19:00 1:19:05 1:19:10 0 2 4 6 8 10 12 14 16 18 20 22 24 Hour Figure 3: Fish vocalizations (n=1696) peak during the early morning and dusk, with a lull during the middle of the day. 1200 Number of Calls 200 400 600 800 1000 0 Daily Whale Calling 0 2 4 6 8 10 12 14 16 18 20 22 24 Hour Figure 4: Whale vocalizations (n=6644) don't exhibit any particular pattern of presence throughout the day. 009 Figure 7: Spectrogram depicting the presence of fish calls as indicated by the red arrows. The remaining yellow vertical lines are the snapping sounds made by snapping shrimp. 2.40- 2.30- 2.20- 2.10- 2.00- 1.90- 1.80- 1.70- 1.60- 1.50- 1.40- 1.30- 1.20- 1.10- 1.00- 0.90- 0.80- 0.70- 0.60- 0.50- 0.40- 0.30- 0.20- 0.00 kHz, "h:m:s 3:01:27.876 3:01:35 3:01:40 3:01:45 3:01:50 3:01:55 3:02:00 3:02:05 3:02:10 3:02:15 3:02:20 Figure 8: Spectrogram depicting the presence of whale vocalizations recorded in October 2015. During this month, we detected a total of 6644 whale vocalizations, but none in the other months analyzed, clearly indicating an active time period for whales in the park.. 2.40- 2.30- Daily Non-Natural Detections 2.20- 2.10- 2.00- 1.90- 1.80- 1.70- 1.60- 1.50- 1.40- 1.30 1.20- 1.10- Figure 1: Park staff deployed an underwater microphone, or hydrophone, which recorded the underwater acoustical environment 33m below the surface for one entire year. beginning in June 2015. For our study, we analyzed a representative subsample of these data to help build our understanding of the acoustical environment. 300 400 500 100 Number of Detections 200 0 0 2 4 6 8 10 12 14 16 18 20 22 24 Hour Figure 5: Human-associated noise (n=4078) peaked during the middle of the night and during evening hours, with a lull in the middle of the day. 1.00- 0.90- 0.80- 0.70- 0.60- 0.50- 0.40- 0.30- 0.20- 0.00 kHz s 6.946 10 15 20 25 30 35 40 45 50 55 Figure 9: Spectrogram depicting the presence of a motorized boat passing within the vicinity of the hydrophone. The broadband nature of boat noise has the potential to cover up or mask many biological sounds, potentially disrupting animal communication. 15- Conclusions • This work is helping to establish a baseline understanding of the marine acoustical environment of the National Park of American Samoa. This initial study will inform subsequent studies further examining acoustical data collected within the park. Resulting findings will support management decisions intended to aid species that use acoustic communication. • Extracted sound clips may be used for park interpretation in order to raise visitor awareness about natural sounds and noise pollution in the park, as well as how they interact to affect marine ecosystems. Acknowledgements National Park Service Natural Sounds and Night Skies Division Sound and Light Ecology Team Holger Klinck Samara Haver Leila Hatch Haru Matsumoto Eva DiDonato Tracy Ziegler Nations Online Project SOUTH PACIFIC OCEAN Fagamalo Pico P Fond Building Facatoer Crappy Alono Onenca Cape M Aurasi Aunu' Figure 2: The presence of biological sounds and 2.40 2.20- 2134 human-associated noise in our 2.00- 2131 242729 21482 2144 1.80- subsamples were viewed on 1.60- spectrograms and then logged 1.40- using the acoustical analysis 2124 2539 2137 2540 2149 1.20- software 'Raven'. For 2123 2119 1.00- 2125 2128 spectrograms, the x-axis 0.80- 2122 represents time and the y-axis 2541 2148 2143 2146 2150 2141 ཟེ 0.60- represents frequency or pitch. 2135 2138 0.40- Finally, brighter colors represent louder acoustic events. 2139 2133 2132 2130 0.20 2120 2145 0.00 וח- ΜΠΕ h:m:s1:43:21.666 1:43:26 1:43:31 1:43:36 1:43:41 1:43:46 1:43:51 1:43:56 1:44:01 1:44:06 1:44:11 2152 Figure 6: Whale vocalizations were only seen during the Spring in the waters of National Park of American Samoa. Yearly patterns for fish vocalizations and non-natural noise are not evident, but further investigation using a larger subsample of the acoustical data might better bring into focus any patterns which may exist. Number of Calls per Time Period 10- F 10 ம -5- -10- June/July 2015 (Winter) October 2015 (Spring) February 2016 (Summer) FISH NON-NATURAL WHALE Poloa SAMOA SATANCA BANK College Mound Int. Airport Pavaria Pago Pago ASIA China Japan Leone Cours Futiga chary and Shark Legend Hawaii (U.S.) Philippines Pacific Ocean -Equator- Indonesia Papua New Guinea Indian Ocean AMERICAN SAMOA Australia New Zealand Figure 10: The red star depicts the monitoring location where acoustical data were collected in the National Park of American Samoa. Inset map places the park in a global context.