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Karen N Courtot

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Hawaiian hoary bats (Lasiurus cinereus semotus) were captured at multiple locations on the east side of Hawaii Island from May 2019 to October 2019. Radio transmitters were affixed to captured bats and, when possible, radio telemetry was used to locate bats in trees used for day-roosts. In 2019, three maternity roosts were identified however only two were suitable for video recording. Thermal video recording at two maternal roosts was used to identify the time of bat departure and arrival at a roost. We examined an average of 2 hours during sunset and sunrise (range = 0.9 to 5.4 hours). The time of bat departure from a roost ranged from 53 minutes before sunset to 20 minutes after sunset (n = 48, mean = 2.7 minutes...
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Hawaiian hoary bats ('ōpe'ape'a; Lasiurus semotus) were captured and tracked back to roosting locations on Hawaiʻi Island from 2018-2021. We examined resource selection at multiple spatial scales - perch location within a roost tree, roost tree, and forest stand. We used a discrete choice modeling approach to investigate roost selection and describe attributes of day-roost trees including those used as maternity roosts. ‘Ōpe‘ape‘a were found roosting in a variety of tree species and in an assortment of habitat types including native and non-native habitats. This data release consists of six tabular datasets: (1) Hawaiʻi Island ʻōpeʻapeʻa roost perch metrics, 2019–2021, (2) Hawai‘i Island ʻōpeʻapeʻa roost tree metrics,...
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Our objectives were to examine the population history of axis deer on Maui, estimate observed population growth, and then use species-specific demographic parameters in a VORTEX population viability analysis to examine removal scenarios that would most effectively reduce the population. Only nine deer were introduced in 1959, but recent estimates of >10,000 deer suggest population growth rates (r) ranging between 0.147 and 0.160 although at least 11,200 have been removed by hunters and resource managers. In the VORTEX simulations, we evaluated an initial population size of 6,000 females and 4,000 males, reflecting the probable 3F:2M sex ratio on Maui because of male biased hunting. Scenarios were modeled over a...
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Hawaiian hoary bats (Lasiurus cinereus semotus) were captured at multiple locations on the east side of Hawaii Island from May 2018 through September 2019. Radio transmitters were affixed to captured bats and, when possible, radio telemetry was used to locate bats in trees used for day-roosts. A total of 23 bat day-roosts were identified to tree and used by 18 bats (10 male; 8 female; 17 adult; 1 juvenile). Three maternity roosts were confirmed. One maternity roost was determined to be a bat that was not captured or radio-tagged but was visually located in a roost tree that was also in use by a radio-tagged bat. During the period of monitoring of telemetered bats (less than one month), multiple roosts were located...
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Hawaiian hoary bats ('ōpe'ape'a; Lasiurus semotus) were surveyed at 23 sites on Hawaiʻi Island from 33 to 2,341 m elevation from May 2018 to August 2021. Of the 23 sites, 8 were established as fixed survey sites for sampling at repeated intervals from January 2019 through January 2021. We surveyed each fixed site at least once per four month period (January–April, May–August, September–December), with a survey comprising one to three netting events. Additional opportunistic surveys were conducted at alternate locations or on alternate dates. We captured 138 unique bats (37 female, 101 male) and recaptured 10 bats over 224 mist-netting events. This data file includes data pertaining to mist netting effort locations,...
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