Brief Note: Perching Orientation Affects Number of Feeding Attempts and Seed Consumption by the American Goldfinch (Carduelis tristis)

Author Institution: Department of Biology, Hiram CollegeIn the mid 1800s, J. J. Audubon illustrated American Goldfinches (Carduelis tristis} feeding upside-down to obtain seed from thistles. The influence of feeding orientation on the number of feeding attempts and seed consumption by the American Goldfinch was investigated in the present study. Six rightside up feeders and six upside-down feeders were filled with thistle seed and put on 1.83 m poles. The number of feeding attempts and seed consumption by goldfinches were recorded. Results from one-way ANOVA tests show that goldfinches attempted to feed right-side up more often and ate greater quantities of thistle while feeding in an upright position. The agility of the American Goldfinch may be one reason that this species will readily feed both right-side up or upside-down. However, for the birdwatcher interested in attracting the American Goldfinch, a feeder where birds eat in an upright position is more effective

The influence of habitat features on grassland birds nesting in the Prairie Pothole Region of North Dakota

Results of habitat fragmentation studies on grassland and wetland birds are not consistent. Some studies have found positive relationships among abundance, nest success, field size, and distance to edges, whereas others have found no relationship. One reason for differing results may be the landscape composition in which the study took place. I examined how landscape composition influenced relations among: (1) occurrence and abundance of grassland songbirds and field size, and (2) nest success of ducks, field size, and edges. I also investigated the effects of mowing on grassland songbirds, and how landscape features, such as amount of perennial grassland, and predator community composition influenced the nest success of ducks in fields. The study took place in the Prairie Pothole Region of central North Dakota during the 1996--1997 breeding seasons. Two types of 6.4 x 6.4 km study areas were selected based on the amount of perennial grassland they contained: 15--20%, and 51--55%. The remaining portion of the study areas was primarily cropland and wetland. within the four study areas used, I conducted 281 point counts and found 1,810 duck nests in;46 grassland fields, enrolled in the Conservation Reserve Program, ranging in size from 2--606 ha. Landscape composition influenced relations between field size and relative abundance of 3 grassland songbird species. As the amount of perennial grassland in the landscape increased, the species, abundances in smaller fields increased. Nest success of ducks in fields increased as field size increased, and was greater in study areas with 51--55% grassland compared to 15--20% grassland. I detected an interaction between nest success of ducks and distance to nearest field edge. In study areas with 51--55% grassland, I found a positive relationship between probability of an individual nest hatching and distance to nearest field edge, while in study areas with 15--20% grassland, I found no relationship and probability of hatching was low. Future studies examining the influence of habitat loss and fragmentation on grassland and wetland birds should take into account the landscape context in which the study takes place

The Summer Bird Community in a Late-Successional Beech-Maple Forest in Ohio

Author Institution: Department of Biology, Hiram CollegeWe studied the summer bird community in an unfragmented, late-successional, 61 ha beechmaple forest at the James H. Barrow Field Station in Portage County, Ohio. Birds were surveyed by making 30 counts along either of two trails in June and July of 1992, and recording all individuals seen or heard. During the survey period, we made 958 observations of 29 species. The five most common species, acadian flycatcher (Empidonax virescens), wood thrush (Hylocichia mustelina), red-eyed vireo (yireo olivaceus), hooded warbler (Wilsonia citrina), and northern cardinal (Cardinalis cardinalis') accounted for over 50% of the observations made. Of the 15 Neotropical migrants found, seven have experienced population declines in the eastern United States between 1978 and 1987, and eight are considered to be area-sensitive. The beech-maple forest we surveyed is likely to be a regionally important natural area, for it provides breeding habitat for many declining and area-sensitive bird species that would not be consistently present in smaller, more disturbed forests

The Species Richness of Birds Visiting a Yard Is Influenced by the Feeders/Seeds Present

Although seed preferences of species that visit bird feeders have been well documented, we know little about feeder/seed combinations most appropriate for attracting highest species richness or increasing abundance of individual species. I studied how the species composition of birds visiting a feeding station was influenced by addition of feeders filled with mixed seed, thistle, and suet in a yard that previously contained only a feeder with sunflower seeds. Addition of a seed mixture consisting of hulled sunflower, hulled peanuts, hulled millet, and hulled tree nuts in an elevated platform feeder increased species richness and total number of birds visiting a feeding station. Presence or abundance of Red-bellied Woodpecker (Melanerpes carolinus), Blue Jay (Cyanocitta cristata), American Crow (Corvus brachyrhynchos), European Starling (Sturnus vulgaris), Northern Cardinal (Cardinalis cardinalis), and House Sparrow (Passer domesticus) increased when the seed mixture was added. Presence of White-breasted Nuthatch (Sitta carolinensis) increased when thistle seed in an elevated feeder was present. Addition of a Peanut Treat suet cake in a single-cake capacity, wire-cage increased species richness, and presence or abundance of Red-bellied Woodpecker, Downy Woodpecker (Picoides pubescens), and Hairy Woodpecker (P. villosus) increased when Peanut Treat suet was added. Results indicate that the combination of feeders/seeds placed within a yard influences species composition. These results can be used to make more informed decisions on how to attract species of birds of greatest interest for viewing

Factors Influencing the Occurrence of Birds That Use Feeders in Iowa

Since its inception in 1984, data from the annual Iowa Winter Bird Feeder Survey have provided valuable information about birds that use feeders in Iowa such as spatial and temporal population trends. Using data from the 1988 and 1994 Surveys, we examined how the occurrence of bird species that use feeders was influenced by geographic location, the habitat surrounding a house, and the types of seeds offered at a house. Of the 23 species examined, the occurrence of 8 species was influenced by latitude, 22 species were influenced by the habitat surrounding the house, and 22 species were influenced by the presence of water or the types of food available. Two of the more surprising results from this study were that seven species had a positive relationship between occurrence and corn, and only three species had a positive relationship with the presence of mixed seed. Although people interested in feeding birds may not be able to attract all species, results from this study may be used to increase ones likelihood of viewing individual species of interest

Effects of Field Size and Landscape Composition on Grassland Birds in South-Central Iowa

Many species of grassland birds have been shown to avoid smaller fields. The avoidance of smaller fields, however, has not been consistently reported; avoidance may occur in one study, but not in another. To examine one possible reason for these inconsistencies, we examined how landscape composition influenced the relations between occurrence or abundance and field size. The study took place during the 1998 breeding season on 44 Conservation Reserve Program (CRP) fields located in Adair, Ringgold, and Union counties. The relations between occurrence, abundance, and field size were not influenced by landscape composition for any species. Grasshopper Sparrow, Ammodramus savannarum, Bobolink, Dolichonyx oryzivorus, and Eastern Meadowlark, Sturnella magna, were more likely to occur or were more abundant in larger fields. Field Sparrow, Spize!la pusilla, Western Meadowlark, Sturnella neglecta, Brown-headed Cowbird, Molothrus ater, and American Goldfinch, Carduelis tristis, were less likely to occur or were less abundant in larger fields. Field size is an important factor influencing the occurrence and/or abundance of grassland songbirds in fields. Future studies that investigate the effects of landscape composition on area sensitivity should use landscapes that have similar habitat compositions other than the habitat being varied, and use similar sized fields in each landscape

Simultaneous measurement of flight time and energy of large matrix-assisted laser desorption ionization ions with a superconducting tunnel junction detector

We evaluated a cryogenically cooled superconducting Nb-Al2O3-Nb tunnel junction (STJ) for use as a molecular ion detector in a matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometer. The STJ responds to ion energy and theoretically should detect large molecular ions with a velocity-independent efficiency approaching 100%. The STJ detector produces pulses whose heights are approximately proportional to ion energy, thus the height of a pulse generated by the impact of a doubly charged ion is about twice the height of a singly charged ion pulse. Measurements were performed by bombarding the STJ with human serum albumin (HSA) (66,000 Da) and immunoglobulin (150,000 Da) ions. We demonstrate that pulse height analysis of STJ signals provides a way to distinguish with good discrimination HSA+ from 2HSA2+, whose flight times are coincident. The rise time of STJ detector pulses allows ion flight times to be determined with a precision better than 200 ns, which is a value smaller than the flight time variation typically observed for large isobaric MALDI ions detected with conventional microchannel plate (MCP) detectors. Deflection plates in the flight tube of the mass spectrometer provided a way to aim ions alternatively at a MCP ion detector

Population Trends of Raptors Admitted to the Illinois Raptor Center, 1995-2006

ABSTRACT Raptor population status reflects overall environmental health with various species of hawks and owls responding differently to urbanization, agricultural intensification, and other anthropogenic factors. We examined the population trends of raptors admitted to the Illinois Raptor Center in Decatur, IL from 1995-2006. For the study, 929 raptors of six species admitted to the center were used including Cooper's Hawk (Accipiter cooperii), Red-tailed Hawk (Buteo jamaicensis), American Kestrel (Falco sparverius), Eastern Screech-Owl (Otus asio), Great Horned Owl (Bubo virginianus), and Barred Owl (Strix varia). Changes in the number of raptors admitted per year were examined over time, and compared with changes in land use and human population growth in three central Illinois counties. Except for Barred Owls, the number of raptors admitted changed over time. Observed trends corresponded with Christmas Bird Count data, and the appearance of West Nile Virus in central Illinois may have influenced the number of raptors admitted. We suggest that wildlife rehabilitation centers can be used as an early warning signal of raptor population status

Controlled Spalling of 4H Silicon Carbide with Investigated Spin Coherence for Quantum Engineering Integration

We detail scientific and engineering advances which enable the controlled spalling and layer transfer of single crystal 4H silicon carbide (4H-SiC) from bulk substrates. 4H-SiC’s properties, including high thermal conductivity and a wide bandgap, make it an ideal semiconductor for power electronics. Moreover, 4H-SiC is an excellent host of solid-state atomic defect qubits for quantum computing and quantum networking. Because 4H-SiC substrates are expensive (due to long growth times and limited yield), techniques for removal and transfer of bulk-quality films are desirable for substrate reuse and integration of the separated films. In this work, we utilize updated approaches for stressor layer thickness control and spalling crack initiation to demonstrate controlled spalling of 4H-SiC, the highest fracture toughness crystal spalled to date. We achieve coherent spin control of neutral divacancy (VV0) qubit ensembles and measure a quasi-bulk spin T2 of 79.7 μs in the spalled films

Purcell enhancement of erbium ions in TiO2_{2} on silicon nanocavities

Isolated solid-state atomic defects with telecom optical transitions are ideal quantum photon emitters and spin qubits for applications in long-distance quantum communication networks. Prototypical telecom defects such as erbium suffer from poor photon emission rates, requiring photonic enhancement using resonant optical cavities. Many of the traditional hosts for erbium ions are not amenable to direct incorporation with existing integrated photonics platforms, limiting scalable fabrication of qubit-based devices. Here we present a scalable approach towards CMOS-compatible telecom qubits by using erbium-doped titanium dioxide thin films grown atop silicon-on-insulator substrates. From this heterostructure, we have fabricated one-dimensional photonic crystal cavities demonstrating quality factors in excess of $5\times10^{4}$ and corresponding Purcell-enhanced optical emission rates of the erbium ensembles in excess of 200. This easily fabricated materials platform represents an important step towards realizing telecom quantum memories in a scalable qubit architecture compatible with mature silicon technologies.Comment: 3 figure