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Publications

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How many Laysan Teal Anas laysanensis are on Midway Atoll? Methods for monitoring abundance after reintroduction

Wildlife managers often request a simple approach to monitor the status of species of concern. In response to that need, we used eight years of monitoring data to estimate population size and test the validity of an index for monitoring accurately the abundance of reintroduced, endangered Laysan Teal Anas laysanensis. The population was established at Midway Atoll in the Hawaiian archipelago after
Authors
Michelle H. Reynolds, Karen Courtot, Jeffrey Hatfield

Feral goats and sheep

No abstract available.
Authors
Steve C. Hess, Dirk H. Van Vuren, Gary W. Witmer

Monitoring Hawaiian biodiversity: Pilot study to assess changes to forest birds and their habitat

Biological diversity, or biodiversity, is the variety and abundance of species in a defined area, and is one of the oldest and most basic descriptions of biological communities. Understanding how populations and communities are structured and change over space and time in response to internal and external forces is a management priority. Effective management practices and conservation strategies d
Authors
P. Marcos Gorresen, Richard J. Camp, Jacqueline Gaudioso, Kevin W. Brinck, Paul Berkowitz, James D. Jacobi

No evidence of critical slowing down in two endangered Hawaiian honeycreepers

There is debate about the current population trends and predicted short-term fates of the endangered forest birds, Hawai`i Creeper (Loxops mana) and Hawai`i `Ākepa (L. coccineus). Using long-term population size estimates, some studies report forest bird populations as stable or increasing, while other studies report signs of population decline or impending extinction associated with introduced Ja
Authors
Jessica C. Rozek, Richard J. Camp, J. Michael Reed

Assessing the potential of translocating vulnerable forest birds by searching for novel and enduring climatic ranges

Hawaiian forest birds are imperiled, with fewer than half the original >40 species remaining extant. Recent studies document ongoing rapid population decline and pro- ject complete climate-based range losses for the critically endangered Kaua’i endemics ‘akeke’e (Loxops caeruleirostris) and ‘akikiki (Oreomystis bairdi) by end-of-century due to projected warming. Climate change facilitates the upwa
Authors
Lucas B. Fortini, Lauren R. Kaiser, Adam E. Vorsino, Eben H. Paxton, James D. Jacobi

Monitoring eradication of European mouflon sheep from the Kahuku Unit of Hawai‘i Volcanoes National Park

European mouflon (Ovis gmelini musimon), the world's smallest wild sheep, have proliferated and degraded fragile native ecosystems in the Hawaiian Islands through browsing, bark stripping, and trampling, including native forests within Hawai‘i Volcanoes National Park (HAVO). HAVO resource managers initiated ungulate control efforts in the 469 km2 Kahuku Unit after it was acquired in 2003. We track
Authors
Seth Judge, Steven C. Hess, Jonathan K. Faford, Dexter Pacheco, Christina Leopold

Ecosystem vs. community recovery 25 years after grass invasions and fire in a subtropical woodland

Despite a large body of research documenting invasive plant impacts, few studies have followed individual invaded sites over decades to observe how they change, and none have contrasted how compositional impacts from invasion compare to ecosystem-process impacts over a multi-decadal time-scale. Using direct measurements of plant density and composition and of ecosystems processes, we evaluate h
Authors
Carla M. D'Antonio, Stephanie G. Yelenik, Michelle C. Mack

Program MAMO: Models for avian management optimization-user guide

The following chapters describe the structure and code of MAMO, and walk the reader through running the different components of the program with sample data. This manual should be used alongside a computer running R, so that the reader can copy and paste code into R, observe the output, and follow along interactively. Taken together, chapters 2–4 will allow the user to replicate a simulation stud
Authors
Alban Guillaumet, Eben H. Paxton

Shifts in an invasive rodent community favoring black rats (Rattus rattus) following restoration of native forest

One potential, unintended ecological consequence accompanying forest restoration is a shift in invasive animal populations, potentially impacting conservation targets. Eighteen years after initial restoration (ungulate exclusion, invasive plant control, and out planting native species) at a 4 ha site on Maui, Hawai'i, we compared invasive rodent communities in a restored native dry forest and adja
Authors
Aaron B. Shiels, Arthur C. Medeiros, Erica I. von Allmen

The influence of soil resources and plant traits on invasion and restoration in a subtropical woodland

It has been shown in some cases that nitrogen (N) addition to soil will increase abundance of plant invaders because many invaders have traits that promote rapid growth in response to high resource supply. Similarly, it has been suggested, and sometimes shown, that decreasing soil N via carbon (C) additions can facilitate native species recovery. Yet all species are unlikely to respond to resource
Authors
Stephanie G. Yelenik, Carla M. D'Antonio, Elizabeth August-Schmidt

Biogeographical variation of plumage coloration in the sexually dichromatic Hawai‘i ‘Amakihi (Chlorodrepanis virens)

Plumage coloration in birds can be of major importance to mate selection, social signaling, or predator avoidance. Variations in plumage coloration related to sex, age class, or seasons have been widely studied, but the effect of other factors such as climate is less known. In this study, we examine how carotenoid-based plumage coloration and sexual dichromatism of the Hawai‘i ‘Amakihi (Chlorodrep
Authors
Jacqueline M. Gaudioso-Levita, Patrick J. Hart, Dennis Lapointe, Anne Veillet, Esther Sebastian-Gonzalez

Do you hear what I see? Vocalization relative to visual detection rates of Hawaiian hoary bats (Lasiurus cinereus semotus)

Bats vocalize during flight as part of the sensory modality called echolocation, but very little is known about whether flying bats consistently call. Occasional vocal silence during flight when bats approach prey or conspecifics has been documented for relatively few species and situations. Bats flying alone in clutter-free airspace are not known to forgo vocalization, yet prior observations sugg
Authors
P. Marcos Gorresen, Paul M. Cryan, Kristina Montoya-Aiona, Frank Bonaccorso