Acoustic sampling for occurrence of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus) was conducted at 18 “long-term” acoustic monitoring stations on 12 Hawaii Army National Guard (HIARNG) installations across the islands of Hawaii, Maui, Molokai, Oahu, and Kauai between 2012 and 2018. Hawaiian hoary bat insect prey sampling with paired acoustic monitoring was conducted at Keaukaha Military Reservation (KMR) on Hawaii Island from May to August, 2018. At this property, a herd of domestic goats (occasionally mixed with domestic sheep) were rotated among grazing plots as part of a weed control program managed by HIARNG. We sampled insect abundance and community within the area where goats were used for weed control to better understand if grazing ungulates attract and support potential prey for insectivorous Hawaiian hoary bats. This data release consists of three tabular datasets including bat acoustic activity at all long-term monitoring sites and within the grazing plots at Keaukaha Military Reservation, and insect abundance data from the grazing plots.

Hawaiian hoary bat insect prey sampling with paired acoustic monitoring was conducted at Keaukaha Military Reservation (KMR) on Hawai‘i Island from May to August, 2018. At this property, a herd of domestic goats (occasionally mixed with domestic sheep) were rotated among grazing plots as part of a weed control program managed by Hawaii Army National Guard (HIARNG). Song Meter SM2BAT+ ultrasonic detectors (Wildlife Acoustics, Maynard, MA) with SMX-US ultrasonic microphones (Wildlife Acoustics, Maynard, MA) were deployed at a total of six stations, five monitoring stations (4E, 5F-I) and an additional reference station was established in an ungrazed area with similar non-native grassland habitat approximately 800-m east of the grazing plots. Upon detection of a vocalizing bat, recording was triggered, and a call file was stored with the corresponding date and time. Recordings were analyzed with Kaleidoscope Pro version 5.1.9 (Wildlife Acoustics, Maynard, MA). All files were aurally and visually inspected for bat acoustic activity. At each acoustic monitoring station Hawaiian hoary bat echolocation pulses, call-events and feeding buzzes were summed across sampling nights within each week.

Acoustic sampling for occurrence of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus) was conducted at 12 locations on U. S. Army facilities on O‘ahu Island, Hawai‘i. Bats were confirmed as present at 10 of these locations: Dillingham Military Reservation, Helemano Military Reservation, Kahuku Training Area, Kawailoa Training Area, Mākua Military Reservation, Schofield Barracks East Range, Schofield Barracks West Range, Schofield Barracks (Mendonca Park Housing), Tripler Army Medical Center, and Wheeler Army Airfield. Our acoustic sampling did not record bat vocalizations at Fort DeRussy or Fort Shafter. Despite the presence of bats at the above 10 locations, foraging activity as identified from characteristic feeding buzzes was observed only at East Range and West Range of Schofield Barracks. Within-night bat activity pooled for all nights and detectors at each location showed bat activity was mostly confined to the first several hours of the night. Recordings were analyzed with Kaleidoscope version 4.1.0 (Wildlife Acoustics, Maynard, MA). All files were aurally and visually inspected for bat acoustic activity. The cumulative number of Hawaiian hoary bat echolocation pulses, call-events and feeding buzzes were summed for each monitoring station and night within a month.

Habitat use, diet, prey availability and foraging ecology of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus, Vespertilionidae), was examined in the east Maui region inclusive of the Waihou Mitigation Area, Pu‘u Makua Restoration Area and the wind power facility operated by Auwahi Wind Energy, LLC. Research funding was provided by Auwahi Wind Energy, LLC (Auwahi Wind) to fulfill requirements for mitigating bat fatalities under its approved incidental take permit. The study was conducted to inform the mitigation and management requirements of Auwahi Wind Energy. Acoustic monitoring over the three-year period demonstrated that bats are present and actively feed year-round at the Waihou Mitigation Area.

Habitat use, diet, prey availability and foraging ecology of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus, Vespertilionidae), was examined in the east Maui region inclusive of the Waihou Mitigation Area, Pu‘u Makua Restoration Area and the wind power facility operated by Auwahi Wind Energy, LLC. Research funding was provided by Auwahi Wind Energy, LLC (Auwahi Wind) to fulfill requirements for mitigating bat fatalities under its approved incidental take permit. The study was conducted to inform the mitigation and management requirements of Auwahi Wind Energy. Acoustic monitoring over the three-year period demonstrated that bats are present and actively feed year-round at the Waihou Mitigation Area.

Acoustic sampling for presence of the endangered Hawaiian hoary bat (Lasiurus semotus, also known as Aeorestes semotus) was conducted at 17 stations across four Marine Corps Base Hawaii (MCBH) properties on O‘ahu Island, Hawai‘i. Bats were confirmed as present at all properties; MCBH Kāneʻohe Bay on Mōkapu Peninsula, Marine Corps Training Area Bellows (MCTAB) in Waimanalo, Camp H.M. Smith in Halawa Heights, and Pu'uloa Range Training Facility (RTF) on the 'Ewa coastal plain. Hawaiian hoary bats were recorded in airspace at all four properties during important periods of Hawaiian hoary bat life history, including periods of pregnancy, lactation, and pup fledging; however, overall presence was low. Foraging activity as identified from characteristic feeding buzzes was very rare and was recorded on only three nights over the entire study. Within-night bat detection pooled for all nights and stations at each property showed bat activity was mostly confined to the first several hours of the night at MCBH Kaneohe Bay and Pu'uloa RTF, whereas bat activity was spread throughout the night at Camp H.M. Smith and MCTAB. Recordings were analyzed with Kaleidoscope version 5.1.9h (Wildlife Acoustics Inc, Concord, Massachusetts). This data release consists of one tabular dataset including bat acoustic activity at all stations from February 2019 to March 2021.

Acoustic sampling for presence of the endangered Hawaiian hoary bat (Lasiurus semotus, also known as Aeorestes semotus) was conducted at 17 stations across four Marine Corps Base Hawaii (MCBH) properties on O‘ahu Island, Hawai‘i. Bats were confirmed as present at all properties; MCBH Kāneʻohe Bay on Mōkapu Peninsula, Marine Corps Training Area Bellows (MCTAB) in Waimanalo, Camp H.M. Smith in Halawa Heights, and Pu'uloa Range Training Facility (RTF) on the 'Ewa coastal plain. Hawaiian hoary bats were recorded in airspace at all four properties during important periods of Hawaiian hoary bat life history, including periods of pregnancy, lactation, and pup fledging; however, overall presence was low. Foraging activity as identified from characteristic feeding buzzes was very rare and was recorded on only three nights over the entire study. Within-night bat detection pooled for all nights and stations at each property showed bat activity was mostly confined to the first several hours of the night at MCBH Kaneohe Bay and Pu'uloa RTF, whereas bat activity was spread throughout the night at Camp H.M. Smith and MCTAB. Recordings were analyzed with Kaleidoscope version 5.1.9h (Wildlife Acoustics Inc, Concord, Massachusetts). This data release consists of one tabular dataset including bat acoustic activity at all stations from February 2019 to March 2021.

We examined habitat use and foraging activity of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus), as well as nocturnal aerial insect abundance at Kaloko-Honōkohau National Historical Park located in the coastal region of Kailua-Kona, Hawai‘i Island. The study area covers approximately 486 ha of marine waters and terrestrial coastal plains. Hawaiian hoary bat echolocation vocalizations were recorded at seven acoustic stations between 1 and 10 m above sea level, that operated nightly from November 2013 through February 2015. This data set includes data derived from these acoustic recording stations. Each acoustic recording station was comprised of an acoustic recording unit (SM2Bat+ Song Meter Digital Field Recorder, Wildlife Acoustics, Concord, MA) programmed to record between 10 and 100 kHz. Each recording unit was deployed in a waterproof housing and powered by a 6 V external battery with solar panel for recharging. An ultrasonic microphone (SMX-US, Wildlife Acoustics, Concord, MA) was mounted on a pole 2 to 3 m above the ground and connected by cable to the recording unit. Upon detection of a vocalizing bat, recording was triggered, and a call file was stored with the corresponding date and time on a secure digital (SD) memory card. SD memory cards were replaced every 2-3 months during which times quality checks on microphones were also made. Each recording unit was configured to operate from one hour before local sunset until one hour after local sunrise.

We examined Hawaiian hoary bat (Lasiurus semotus) presence and foraging activity at Hakalau Forest National Wildlife Refuge and Lāupahoehoe Forest Reserve on Hawai‘i Island during the 2013 koa moth (Geometridea: Scotorythra paludicola) outbreak. Hawaiian hoary bat echolocation vocalizations were recorded at seven acoustic stations between 1069 and 1200 m above sea level, that operated nightly from May 2013 through September 2013. We compared these data to data collected at similar locations in 2011 to determine the response of bats to increased moth abundance during 2013. This data set includes data derived from these acoustic recording stations. Each acoustic recording station was comprised of an acoustic recording unit (Anabat SD1, Titely Scientific, Ballina, Australia) programmed to record from 1700 to 0500 each recording night. Each recording unit was deployed in a waterproof housing and powered by a 12 V external battery. An ultrasonic Hi-Mic microphone was mounted inside PVC pipe oriented toward the ground to prevent rain damage. A 15 x 15 cm plexiglass plate was attached below the microphone at a 45-degree angle to reflect and enhance calls from bats flying above the microphone. The PVC and microphone were affixed to the top of a 7- meter steel pole. Anabat Hi-Mics in this configuration have an omnidirectional maximum effective range of 30 meters. Upon detection of a vocalizing bat a call file was stored with the corresponding date and time on a compact flash (CF) memory card. Memory cards and batteries were replaced every 1-2 weeks during which quality checks on equipment were made. In this abstract we refer to the Hawaiian hoary bat as a full species, Lasiurus semotus, following updated taxonomy for Hawaiian hoary bats (Pinzari et al. 2020; see full citation below in the cross-references section).

We examined Hawaiian hoary bat (Lasiurus semotus) presence and foraging activity at Hakalau Forest National Wildlife Refuge and Lāupahoehoe Forest Reserve on Hawai‘i Island during the 2013 koa moth (Geometridea: Scotorythra paludicola) outbreak. Hawaiian hoary bat echolocation vocalizations were recorded at seven acoustic stations between 1069 and 1200 m above sea level, that operated nightly from May 2013 through September 2013. We compared these data to data collected at similar locations in 2011 to determine the response of bats to increased moth abundance during 2013. In this abstract we refer to the Hawaiian hoary bat as a full species, Lasiurus semotus, following updated taxonomy for Hawaiian hoary bats (Pinzari et al. 2020; see full citation below in the cross-references section).