The Journal of the Acoustical Society of America, 2013
ABSTRACT The Mariana Swiftlet (Aerodramus bartschi) is a federally listed endangered species of i... more ABSTRACT The Mariana Swiftlet (Aerodramus bartschi) is a federally listed endangered species of is native to Guam and the Marianas Islands. There is also a small, introduced population of Marianas Swiftlets on the island of Oahu, Hawaii. The nesting cave in Oahu is a small tunnel built for agricultural irrigation. Marianas swiftlets live in caves, which they navigate using echolocation clicks. Ecological Acoustical Recorders (EARs) were modified with a omni-directional microphone with a flat frequency response and -63 dB sensitivity for bird recordings. Data were recorded at a sample rate of 80,000 and a duty cycle of 30 s of recording every 5 min. BEARs (Bird EARs) were placed in swiftlet caves on Oahu, Hawaii, and Guam where they recorded for between five and fifteen days. Swiftlet clicks were detected using Ishmael's energy sum detector. Temporal patterns of clicking were analyzed and compared between the two sites and correlated with environmental data over the recording period to determine effects of sub-optimal nesting habitat and changed weather patterns on the Oahu population compared to the native population in Guam.
The Journal of the Acoustical Society of America, 2005
The singing behavior of male humpback whales on the winter breeding grounds is still a poorly und... more The singing behavior of male humpback whales on the winter breeding grounds is still a poorly understood phenomenon. Previous work indicates that the chorusing levels of singing whales off west Maui are higher at night than during the day. However, the cause of this variation is not known. To investigate whether more whales sing at night or whether the same
The Journal of the Acoustical Society of America, 2005
Songs sung by male humpback whales consist of distinct, pulsed sounds that are designated as unit... more Songs sung by male humpback whales consist of distinct, pulsed sounds that are designated as units. Units are produced in some sequence to form a phrase, a repeated set of phrases forms a theme, and repeated themes form a song. A song can last from minutes to hours. The songs of eight humpback whales were recorded with a vertical array
The Journal of the Acoustical Society of America, 2007
Vocalizations from the northern right whale dolphin, Lissodelphis borealis, were recorded during ... more Vocalizations from the northern right whale dolphin, Lissodelphis borealis, were recorded during a combined visual and acoustic shipboard survey of cetacean populations off the west coast of the United States. Seven of twenty single-species schools of L. borealis produced click and pulsed vocalizations. No whistles were detected during any of the encounters. Clicks associated with burst-pulse vocalizations were lower in frequency and shorter in duration than clicks associated with echolocation. All burst-pulse sounds were produced in a series containing 6-18 individual burst-pulses. These burst-pulse series were stereotyped and repeated. A total of eight unique burst-pulse series were detected. Variation in the temporal characteristics of like units compared across repeated series was less than variation among all burst-pulses. These stereotyped burst-pulse series may play a similar communicative role as do stereotyped whistles found in other delphinid species.
The Journal of the Acoustical Society of America, 2013
ABSTRACT The Mariana Swiftlet (Aerodramus bartschi) is a federally listed endangered species of i... more ABSTRACT The Mariana Swiftlet (Aerodramus bartschi) is a federally listed endangered species of is native to Guam and the Marianas Islands. There is also a small, introduced population of Marianas Swiftlets on the island of Oahu, Hawaii. The nesting cave in Oahu is a small tunnel built for agricultural irrigation. Marianas swiftlets live in caves, which they navigate using echolocation clicks. Ecological Acoustical Recorders (EARs) were modified with a omni-directional microphone with a flat frequency response and -63 dB sensitivity for bird recordings. Data were recorded at a sample rate of 80,000 and a duty cycle of 30 s of recording every 5 min. BEARs (Bird EARs) were placed in swiftlet caves on Oahu, Hawaii, and Guam where they recorded for between five and fifteen days. Swiftlet clicks were detected using Ishmael's energy sum detector. Temporal patterns of clicking were analyzed and compared between the two sites and correlated with environmental data over the recording period to determine effects of sub-optimal nesting habitat and changed weather patterns on the Oahu population compared to the native population in Guam.
The Journal of the Acoustical Society of America, 2005
The singing behavior of male humpback whales on the winter breeding grounds is still a poorly und... more The singing behavior of male humpback whales on the winter breeding grounds is still a poorly understood phenomenon. Previous work indicates that the chorusing levels of singing whales off west Maui are higher at night than during the day. However, the cause of this variation is not known. To investigate whether more whales sing at night or whether the same
The Journal of the Acoustical Society of America, 2005
Songs sung by male humpback whales consist of distinct, pulsed sounds that are designated as unit... more Songs sung by male humpback whales consist of distinct, pulsed sounds that are designated as units. Units are produced in some sequence to form a phrase, a repeated set of phrases forms a theme, and repeated themes form a song. A song can last from minutes to hours. The songs of eight humpback whales were recorded with a vertical array
The Journal of the Acoustical Society of America, 2007
Vocalizations from the northern right whale dolphin, Lissodelphis borealis, were recorded during ... more Vocalizations from the northern right whale dolphin, Lissodelphis borealis, were recorded during a combined visual and acoustic shipboard survey of cetacean populations off the west coast of the United States. Seven of twenty single-species schools of L. borealis produced click and pulsed vocalizations. No whistles were detected during any of the encounters. Clicks associated with burst-pulse vocalizations were lower in frequency and shorter in duration than clicks associated with echolocation. All burst-pulse sounds were produced in a series containing 6-18 individual burst-pulses. These burst-pulse series were stereotyped and repeated. A total of eight unique burst-pulse series were detected. Variation in the temporal characteristics of like units compared across repeated series was less than variation among all burst-pulses. These stereotyped burst-pulse series may play a similar communicative role as do stereotyped whistles found in other delphinid species.
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