Stager M.,University of Illinois at Urbana - Champaign |
Cerasale D.J.,WestLand Resources Inc. |
Dor R.,Tel Aviv University |
Winkler D.W.,Cornell University |
Cheviron Z.A.,University of Illinois at Urbana - Champaign
Gene | Year: 2014
Latitudinal variation in avian life histories can be summarized as a slow-fast continuum, termed the 'pace of life', that encompasses patterns in life span, reproduction, and rates of development among tropical and temperate species. Much of the variation in avian pace of life is tied to differences in rates of long-term metabolic energy expenditure. Given the vital role of the mitochondrion in metabolic processes, studies of variation in the mitochondrial genome may offer opportunities to establish mechanistic links between genetic variation and latitudinal 'pace of life' patterns. Using comparative genomic analyses, we examined complete mitochondrial genome sequences obtained from nine, broadly distributed Tachycineta swallow species to test for signatures of natural selection across the mitogenome within a phylogenetic framework. Our results show that although purifying selection is the dominant selective force acting on the mitochondrial genome in Tachycineta, three mitochondrial genes (. ND2, ND5, and CYTB) contain regions that exhibit signatures of diversifying selection. Two of these genes (. ND2 and ND5) encode interacting subunits of NADH dehydrogenase, and amino residues that were inferred to be targets of positive selection were disproportionately concentrated in these genes. Moreover, the positively selected sites exhibited a phylogenetic pattern that could be indicative of adaptive divergence between "fast" and "slow" lineages. These results suggest that functional variation in cytochrome b and NADH dehydrogenase could mechanistically contribute to latitudinal 'pace of life' patterns in Tachycineta. © 2014 Elsevier B.V.
Best A.,WestLand Resources Inc |
Diamond G.,WestLand Resources |
Diamond J.,Wildlife Contracts Branch |
Buecher D.,WestLand Resources |
And 3 more authors.
Park Science | Year: 2015
To protect a lesser long-nosed bat post-maternity roost, the National Park Service installed bat-compatible gates on the entrances to the abandoned State of Texas Mine within Coronado National Memorial in southeastern Arizona. Video camcorder surveys performed during peak occupation of this roost examined colony size, gate-induced injury or mortality, and bat exit rates. Although the colony decreased in size after the installation of the gate, the reduced number of bats cannot with certainty be attributed to the presence of the gate. A large wildfire and drought likely contributed to reduced numbers. The study did not find evidence that the gates caused injury or mortality, or impeded the bats while exiting the roost. Further monitoring could ensure that lesser long-nosed bats continue to use the State of Texas Mine. © 2015, National Park Service. All rights reserved.
Diamond J.M.,Wildlife Contracts Branch |
Gwinn R.N.,Wildlife Contracts Branch |
Johnson J.,U.S. Army |
Telle H.,U.S. Army |
Diamond G.F.,Westland Resources Inc.
Western North American Naturalist | Year: 2015
Big brown bats (Eptesicus fuscus) and a close relative of Arizona myotis (Myotis occultus), the little brown bat (Myotis lucifugus) in the eastern United States, are among those species experiencing unprecedented population declines related to white-nose syndrome (WNS). Determining population characteristic baselines for big brown bat and Arizona myotis is paramount in detecting population declines before they reach critical levels. We targeted 2 bat species strongly associated with ponderosa pine forests in northern Arizona. Big brown bats and Arizona myotis readily utilize human-made structures and have a cosmopolitan distribution across the ponderosa pine (Pinus ponderosa) ecosystem of northern Arizona (Adams 2003). Between 2005 and 2012 we installed artificial bat roosts at Camp Navajo near Flagstaff, Arizona. We captured bats at these roosting structures and marked them using modified bird bands. We established baseline population characteristics on Camp Navajo by utilizing a 7-year mark-and-recapture data set. We also provide a measure of population status that may be compared across temporal scales within the study area. In essence, this study provides the basis for an early warning system for WNS in Arizona. © 2015 Western North American Naturalist.
Diamond G.F.,WestLand Resources Inc. |
Diamond J.M.,Wildlife Contracts Branch
Western North American Naturalist | Year: 2014
With the loss and modification of natural roosting habitat afforded by caves, abandoned mines have assumed increased importance as alternative roosting sites for Townsend's big-eared bats (Corynorhinus townsendii). However, increased human safety concerns have led to accelerated abandoned mine closure programs. To protect roosting sites in mines with significant bat activity, bat-compatible gates are installed that allow continued access to mine workings. Aside from ensuring public safety, these gates provide protection from disturbance to roosting bats. We evaluated the effects of gating on bat flight behavior at maternity colonies in 2 previously gated (control) and 2 ungated (treatment) mines that were gated during this study. We used an infrared video camera to record bat flight behavior at the entrances to each of the 4 study mines for 2 consecutive mornings and a single night each month during the warm season. Entrance (03:00-06:00) and emergence (21:00-24:00) surveys comprised 3 consecutive hours. Overall circling activity increased more than 6-fold at openings of treatment mines following gating (P < 0.001). Crowding during emergence was significantly higher (P = 0.023) in newly gated mines than in previously gated mines. Gates affect subadults during the initial-volancy periods, as detected through collisions with the gates. Increased activity of bats and collisions with the gate, which result in bats falling to the ground at mine openings, may amplify vulnerability to predators and increase energetic demands. © 2014.