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Publications

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Extreme drought alters frequency and reproductive success of floaters in Willow Flycatchers

Changes in habitat quality, including those caused by extreme events like droughts and floods, could alter costs and benefits of territoriality and thereby the prevalence and reproductive consequences for individuals capable of breeding that do not do so (floaters). We studied floating behavior in a population of Southwestern Willow Flycatchers (Empidonax traillii extimus) in central Arizona durin
Authors
Tad Theimer, Mark K. Sogge, Suzanne N. Cardinal, Scott L. Durst, Eben H. Paxton

The epidemiology of avian pox and interaction with avian malaria in Hawaiian forest birds

Despite the purported role of avian pox (Avipoxvirus spp.) in the decline of endemic Hawaiian birds, few studies have been conducted on the dynamics of this disease, its impact on free‐living avian populations, or its interactions with avian malaria (Plasmodium relictum). We conducted four longitudinal studies of 3–7 yr in length and used generalized linear models to evaluate cross‐sectional preva
Authors
Michael Samuel, Bethany L. Woodworth, Carter T. Atkinson, Patrick J. Hart, Dennis Lapointe

Ecological genomics predicts climate vulnerability in an endangered southwestern songbird

Few regions have been more severely impacted by climate change in the USA than the Desert Southwest. Here, we use ecological genomics to assess the potential for adaptation to rising global temperatures in a widespread songbird, the willow flycatcher (Empidonax traillii), and find the endangered desert southwestern subspecies (E. t. extimus) most vulnerable to future climate change. Highly signifi
Authors
Kristin Ruegg, Rachael A. Bay, Eric C. Anderson, James F. Saracco, Ryan J. Harrigan, Mary J. Whitfield, Eben H. Paxton, Thomas B. Smith

Characterization of Plasmodium relictum, a cosmopolitan agent of avian malaria

BackgroundMicroscopic research has shown that Plasmodium relictum is the most common agent of avian malaria. Recent molecular studies confirmed this conclusion and identified several mtDNA lineages, suggesting the existence of significant intra-species genetic variation or cryptic speciation. Most identified lineages have a broad range of hosts and geographical distribution. Here, a rare new linea
Authors
Gediminas Valkiunas, Mikas Ilgūnas, Dovilė Bukauskaitė, Karin Fragner, Herbert Weissenböck, Carter T. Atkinson, Tatjana Iezhova

Biology and impacts of Pacific Islands invasive species. 14. Sus scrofa the feral pig (Artiodactyla: Suidae)

Feral pigs (Sus scrofa L.) are perhaps the most abundant, widespread, and economically significant large introduced vertebrate across the Pacific island region. Unlike many other nonnative invasive species, feral pigs have both cultural and recreational importance in the region, complicating their management. Today, Pacific island feral pigs are a mixture of several strains of domestic swine, Asia
Authors
Nathaniel H. Wehr, Steven C. Hess, Creighton M. Litton

Potential impacts of projected climate change on vegetation management in Hawai`i Volcanoes National Park

Climate change will likely alter the seasonal and annual patterns of rainfall and temperature in Hawai`i. This is a major concern for resource managers at Hawai`i Volcanoes National Park where intensely managed Special Ecological Areas (SEAs), focal sites for managing rare and endangered plants, may no longer provide suitable habitat under future climate. Expanding invasive species’ distributions
Authors
Richard J. Camp, Rhonda Loh, S. Paul Berkowitz, Kevin W. Brinck, James D. Jacobi, Jonathan Price, Sierra McDaniel, Lucas B. Fortini

Population estimates of the Endangered Hawaiʻi ʻĀkepa (Loxops coccineus) in different habitats on windward Mauna Loa

Endangered Hawai‘i ʻĀkepas (Loxops coccineus) are endemic to Hawai‘i island, where they occur in five spatially distinct populations. Data concerning the status and population trends of these unique Hawaiian honeycreepers are crucial for assessing the effectiveness of recovery and management actions. In 2016, we used point‐transect distance sampling to estimate the abundance of Hawai‘i ʻĀkepas in
Authors
Seth W. Judge, Richard J. Camp, Patrick J. Hart, Scott T. Kichman

The effect of isolation, fragmentation, and population bottlenecks on song structure of a Hawaiian honeycreeper

Little is known about how important social behaviors such as song vary within and among populations for any of the endemic Hawaiian honeycreepers. Habitat loss and non‐native diseases (e.g., avian malaria) have resulted in isolation and fragmentation of Hawaiian honeycreepers within primarily high elevation forests. In this study, we examined how isolation of Hawai'i ‘amakihi (Chlorodrepanis viren
Authors
Joshua M. Pang-Ching, Kristina L. Paxton, Eben H. Paxton, Adam A. Pack, Patrick J. Hart

Rapid colonization of a Hawaiian restoration forest by a diverse avian community

Deforestation of tropical forests has led to widespread loss and extirpation of forest bird species around the world, including the Hawaiian Islands which have experienced a dramatic loss of forests over the last 200–800 years. Given the important role birds play in forest ecosystem functions via seed dispersal and pollination, a bird community's response to forest restoration is an important meas
Authors
Eben H. Paxton, Stephanie G. Yelenik, Tracy E. Borneman, Eli Rose, Richard J. Camp, Steve J. Kendall

Vegetation response of a dry shrubland community to feral goat management on the island of Moloka‘i, Hawai‘i

The Hawaiian Islands are well known for their unique ecosystem assemblages that have a high proportion of endemic flora and fauna. However, since human colonization of this archipelago—starting with the arrival of Polynesian sailors approximately 1,200 years ago, and particularly following western contact in 1778—thousands of non-native species have been introduced to the Islands and many of these
Authors
James D. Jacobi, Jonathan D. Stock

Parasite spillover: Indirect effects of invasive Burmese pythons

Identification of the origin of parasites of nonindigenous species (NIS) can be complex. NIS may introduce parasites from their native range and acquire parasites from within their invaded range. Determination of whether parasites are non-native or native can be complicated when parasite genera occur within both the NIS’ native range and its introduced range. We explored potential for spillover an
Authors
Melissa A. Miller, John M. Kinsella, Ray W. Snow, Malorie M Hayes, Bryan Falk, Robert Reed, Frank J. Mazzotti, Craig Guyer, Christina M. Romagosa

Interactions among invasive plants: Lessons from Hawai‘i

Most ecosystems have multiple-plant invaders rather than single-plant invaders, yet ecological studies and management actions focus largely on single invader species. There is a need for general principles regarding invader interactions across varying environmental conditions, so that secondary invasions can be anticipated and managers can allocate resources toward pretreatment or postremoval acti
Authors
Carla M. D'Antonio, Rebecca Ostertag, Susan Cordell, Stephanie G. Yelenik