bluuebunny/crossref_metadata_2025_split huggingface dataset:
When Time is of the Essence: Preliminary Findings for a Quick Administration of the Dot Counting Test
Authors: Bailey K Chase , Webber Troy A , Phillips Jacob I , Kraemer Lindsay D R , Marceaux Janice C , Soble Jason R 
Published: October 2019

Abstract

Objective
Performance validity research has emphasized the need for briefer measures and, more recently, abbreviated versions of established free-standing tests to minimize neuropsychological evaluation costs/time burden. This study examined the accuracy of multiple abbreviated versions of the Dot Counting Test (“quick” DCT) for detecting invalid performance in isolation and in combination with the Test of Memory Malingering Trial 1 (TOMMT1).

Method
Data from a mixed clinical sample of 107 veterans (80 valid/27 invalid per independent validity measures and structured criteria) were included in this cross-sectional study; 47% of valid participants were cognitively impaired. Sensitivities/specificities of various 6- and 4-card DCT combinations were calculated and compared to the full, 12-card DCT. Combined models with the most accurate 6- and 4-card combinations and TOMMT1 were then examined.

Results
Receiver operator characteristic curve analyses were significant for all 6- and 4-card DCT combinations with areas under the curve of .868–.897. The best 6-card combination (cards, 1-3-5-8-11-12) had 56% sensitivity/90% specificity (E-score cut-off, ≥14.5), and the best 4-card combination (cards, 3-4-8-11) had 63% sensitivity/94% specificity (cut-off, ≥16.75). The full DCT had 70% sensitivity/90% specificity (cut-off, ≥16.00). Logistic regression revealed 95% classification accuracy when 6-card or 4-card “quick” combinations were combined with TOMMT1, with the DCT combinations and TOMMT1 both emerging as significant predictors.

Conclusions
Abbreviated DCT versions utilizing 6- and 4-card combinations yielded comparable sensitivity/specificity as the full DCT. When these “quick” DCT combinations were further combined with an abbreviated memory-based performance validity test (i.e., TOMMT1), overall classification accuracy for identifying invalid performance was 95%.
Nest Attendance of Parent Birds in the Painted Snipe (Rostratula benghalensis)
Authors: Komeda Shigemoto 
Published: October 2019

Abstract
I observed 15 pairs of Painted Snipes (Rostratula benghalensis) in Japan for 24-h periods in order to compare the nest attendance behavior of males and females and to document changes in their behavior during the laying period. From a few days before the laying of the first egg until the day the second egg was laid, the male and female consorted with each other (stayed within 5 m of each other) more than 90% of the observation time. They visited the nest repeatedly on the first and second days of laying. On the third day, the consorting ratio decreased to 58.5%, and the male typically started to incubate. He continued to incubate that night. After laying the third egg, the female usually did not visit the nest except to lay the fourth and last egg. The male continued incubation, and the female met her mate only when she laid the last egg. The absence of female incubation and the early termination of consorting behavior are consistent with the possibility that Painted Snipe females are polyandrous.
Fruits and the Ecology of Resplendent Quetzals
Authors: Wheelwright Nathaniel T. 
Published: October 2019

Abstract
Resplendent Quetzals (Pharomachrus mocinno) are typically termed "specialized" fruit-eating birds, although there are few data describing the breadth of their diet or the characteristics of the fruits they select. In fact, there is no general consensus about the meaning or consequences of being a fruit specialist. In the lower montane forests at Monteverde, Costa Rica, quetzals feed on a minimum of 12-18 species of fruits at most times of the year and on an annual total of at least 41 species. Although their diet includes the watery, small-seeded berries of many second-growth plants, they depend mostly on the large drupes of about 18 species in the laurel family (Lauraceae). The phenologies and habitat distributions of the Lauraceae appear to dictate the timing and direction of seasonal movements by quetzals. Mutual dependence and, possibly, general coevolution between quetzals and the lauraceous trees whose seeds they disperse are suggested by the birds' morphology, distribution, behavior, and life history.
Nestling quetzals are brought entire fruits as early as the second day after hatching. Thereafter, they consume gradually increasing amounts of fruit, but, even immediately before they fledge, most of their diet consists of insects, snails, and lizards. Brooding drops off rapidly by the time chicks are 9 days old. Considerable variation in brooding duration, parental sex roles, and nestling diet exists between nests, however, and apparently between clutches. Adults take far less time to deliver fruits to nestlings than to deliver insects or lizards, which reflects the relative ease of "capturing" ripe fruits (as opposed to animal prey) during the breeding season. The male parent delivered significantly more insects and food items in general than did the female at a first-clutch nest but not at a second-clutch nest.
Several Central American montane reserves have been established to protect populations of quetzals, the national symbol of Guatemala and an important tourist attraction throughout the Isthmus. Unfortunately, the reserves tend to be too small and to include only a limited representation of critical habitats. If other Central American quetzal populations are similar to Monteverde's, the birds must migrate to different habitats as the availability of ripe fruits fluctuates between seasons or years. Once reserves become isolated by deforestation, they will fail to prevent local extinction of quetzals.
Mechanism and Ecological Significance of Sperm Storage in the Northern Fulmar with Reference to Its Occurrence in Other Birds
Authors: Hatch Scott A. 
Published: October 2019

Abstract
Sperm-storage glands were found in the uterovaginal (UV) region of the oviduct in Northern Fulmars (Fulmarus glacialis), Horned Puffins (Fratercula corniculata), and Leach's Storm-Petrels (Oceanodroma leucorhoa) collected before or shortly after egg laying. Previously described only in domestic Galliformes, UV sperm-storage glands may prove to be a common feature of the avian reproductive system. There is as yet no compelling explanation of their function in the Horned Puffin. In the Northern Fulmar, and probably in other petrels, however, sperm-storage glands allow the separation of the male and female over pelagic waters for several weeks immediately before egg laying. The likelihood of prolonged viability of sperm in the female reproducitve tract should be considered in interpreting the sexual behavior of other wild birds.
The Relationships of the Starlings (Sturnidae: Sturnini) and the Mockingbirds (Sturnidae: Mimini)
Authors: Sibley Charles G. , Ahlquist Jon E. 
Published: October 2019

Abstract
Old World starlings have been thought to be related to crows and their allies, to weaverbirds, or to New World troupials. New World mockingbirds and thrashers have usually been placed near the thrushes and/or wrens. DNA-DNA hybridization data indicated that starlings and mockingbirds are more closely related to each other than either is to any other living taxon. Some avian systematists doubted this conclusion. Therefore, a more extensive DNA hybridization study was conducted, and a successful search was made for other evidence of the relationship between starlings and mockingbirds. The results support our original conclusion that the two groups diverged from a common ancestor in the late Oligocene or early Miocene, about 23-28 million years ago, and that their relationship may be expressed in our passerine classification, based on DNA comparisons, by placing them as sister tribes in the Family Sturnidae, Superfamily Turdoidea, Parvorder Muscicapae, Suborder Passeres. Their next nearest relatives are the members of the Turdidae, including the typical thrushes, erithacine chats, and muscicapine flycatchers.
Energy Invested in Reproduction by Thick-Billed Murres (Uria lomvia)
Authors: Gaston A. J. 
Published: October 2019

Abstract
Pelagic seabirds that lay single-egg clutches have been thought to invest less energy in reproduction than inshore-feeding species that rear more than one young. To examine this idea I calculated time and energy budgets for Thick-billed Murres (Uria lomvia) breeding at two large arctic colonies and compared their energy expenditure with that of a hypothetical group (shirkers) that was capable of feeding at the same rate but did not attempt any reproductive activity. The difference in energy investment between breeders and shirkers was strongly dependent on the average foraging range. I also compared my results with similar estimates for inshore-feeding Black Guillemots (Cepphus grylle). For the two Thick-billed Murre colonies, energy allocated to reproduction represented 30% and 24% of total energy expenditure during the breeding season. These values exceed the estimates for Black Guillemots. The amount of energy invested by Thick-billed Murres at the colonies considered probably is similar to that invested by other seabirds laying larger clutches and rearing heavier young.
Courtship Feeding and Osprey Reproduction
Authors: Poole Alan 
Published: October 2019

Abstract
A female Osprey (Pandion haliaetus) usually is fed exclusively by its mate between pair formation and egg-laying. Laying dates and courtship periods-but not clutch size, egg size, breeding success, or female weight reserves-were correlated (negatively) with the prelaying feeding rates of 12 females breeding in a coastal Massachusetts colony. However, the age of a pair and of its bond influenced laying dates and courtship periods more than food intake. Older and more experienced pairs arrived earlier and laid eggs more quickly than younger pairs. As an independent test of food limitation in Ospreys producing eggs, supplemental food was provided to 4 nests during courtship. Supplemental food did not influence a female's reproductive output or timing, but males at nests receiving extra food showed reduced rates of foraging. Egg production boosted the daily energy expenditure of female Ospreys by only about 20% and females gained little weight during courtship, suggesting that egg-laying is not a demanding process in this species. Because age and mate retention had a greater effect on the reproductive output and timing of female Ospreys than rates of food consumption during courtship, and because there was evidence that poorly fed females were less willing to copulate and less faithful to their mates than well-fed females, it is argued that Osprey courtship feeding may function primarily to ensure mate fidelity.
Coloniality in the Yellow-Rumped Cacique as a Defense against Nest Predators
Authors: Robinson Scott K. 
Published: October 2019

Abstract
Individuals of the colonial Yellow-rumped Cacique (Cacicus cela) in Amazonian Peru can defend their nests against predators in three ways. First, by nesting on islands and around wasp nests, caciques are safe from arboreal mammals such as primates, which destroy many more-accessible colonies. Caimans and otters that live in lakes also protect island colonies from snakes, which are vulnerable when crossing open water. Second, by clustering nests together and mobbing as a group, caciques can deter many avian predators, which take spatially isolated nests in small colonies. The effectiveness of mobbing increases with group size, which in turn is correlated with colony size. Third, by mixing their enclosed, pouchlike nests with abandoned nests, caciques can hide their nests from some predators. Overall, nests in clusters on islands and around wasp nests suffer the least predation, largely because they are well protected against the cacique's major predators. Females switch colonies after losing nests to a predator, usually to sites that offer protection against that predator. By this mechanism, the best colony sites accumulate the largest numbers of nests. It is unclear, however, why all females do not nest in the safest colony sites. I argue that nest predation favors coloniality because of the scarcity of nest sites that are safe from mammals and the increased effectiveness of group defense.
Moonlight Avoidance Behavior in Leach's Storm-Petrels as a Defense against Slaty-Backed Gulls
Authors: Watanuki Yutaka 
Published: October 2019

Abstract
Diurnal activity patterns of Leach's Storm-Petrels (Oceanodroma leucorhoa) and Slaty-backed Gulls (Larus schistisagus) were investigated. The petrels reduced activity in moonlight in May and June when the predation rate by gulls was relatively high. Petrel activity levels were inversely correlated with light intensities and the corresponding risk of predation by the gull. This suggests that nocturnal activity and moonlight avoidance by the petrel in its colony are an effective defense against diurnal predators. Activity synchronization of the petrel was most marked during the full moon, further supporting the predator-avoidance hypothesis.
Effects of Body Weight and Age on the Time of Pairing of American Black Ducks
Authors: Hepp Gary R. 
Published: October 2019

Abstract
I used captive young and adult American Black Ducks (Anas rubripes) during October-February 1984-1985 to test whether body weight and age affected time of pair-bond formation. Eighty ducks were marked individually, and 10 ducks (6 males and 4 females, half of each age class) were assigned to each of 8 experimental pens. Ducks in 4 pens received an ad libitum diet of commercial duck food, and ducks in the other 4 pens received a restricted ration of the same food. During early winter ducks in both groups gained weight, but ducks on the restricted diet gained less than birds on the ad libitum diet; peak winter weight of ducks on the ad libitum diet averaged 22% greater than initial body weight compared with 6.5% for ducks on the restricted diet. In late winter ducks on the restricted diet lost 28.7% of peak winter weight, and ducks on the ad libitum diet lost 19.3%. Weight loss of ducks on the ad libitum diet began before weather conditions became severe and coincided with a reduction in food consumption. This result supports the idea that weight loss of waterfowl in late winter is controlled endogenously. Individuals on the ad libitum diet paired earlier than those on the restricted diet, and pair bonds were stronger. Adults of both sexes paired earlier than young ducks, but differences for females were not significant statistically. Age and energy constraints are factors that can affect intraspecific variation in pairing chronology.
Predation as a Selective Force on Foraging Herons: Effects of Plumage Color and Flocking
Authors: Caldwell Gloria S. 
Published: October 2019

Abstract
Experiments using model herons in natural mangrove habitats demonstrated that more hawks are attracted to white than to blue herons. Both Common Black-Hawks (Buteogallus anthracinus) and crocodiles (Crocodylus acutus) were observed preying on adult herons in Panama. Solitary herons were at greater risk than flocked foragers. White (immature) Little Blue Herons (Egretta caerulea) were attacked more frequently by hawks than were the blue adults of their species. Dark herons gave more alarms than white herons. Although flock size decreased in years of heavy predation and after attacks, mixed-flock composition remained the same. When flocks re-formed after hawk attacks, their members showed decreased foraging rates and increased interindividual distances. After repeated attacks, herons foraged in poorer habitats, under unfavorable climatic conditions, and under thermoregulatory stress. These results suggest that predation could be a potent force in maintaining color dimorphism in ardeids.
Fish Crow Predation on Eggs of the White Ibis at Battery Island, North Carolina
Authors: Shields Mark A. , Parnell James F. 
Published: October 2019

Abstract
We studied predation by Fish Crows (Corvus ossifragus) on eggs of the White Ibis (Eudocimus albus) during the 1983 and 1984 nesting seasons at Battery Island, southeastern North Carolina. Crow predation accounted for the loss of 32% (n = 223) of ibis eggs in 1983 and 44% (n = 538) in 1984. Crows usually took all eggs in a clutch. An estimated 6 pairs of Fish Crows nested on the island each year. We believe these individuals were responsible for most egg loss. The predation rate of ibis clutches was highest in plots nearest crow nests and lowest in two plots that contained observation blinds. Results of experiments using simulated ibis nests suggested that crows were wary of the blinds. Predation declined with nest age, apparently due to increased nest attentiveness by adult ibises during the last week of incubation. The overall predation rate in 1984 was significantly higher than in 1983. Greater nest densities and less synchronous breeding by ibises in 1984 may have contributed to the higher predation rate. Ibis productivity was estimated at 1.22-1.30 fledglings per pair in 1983 and 1.05-1.12 in 1984. This level of reproduction appeared sufficient for maintenance of the population. Thus, egg predation by Fish Crows during our study did not appear to be a serious threat to the productivity of this White Ibis population.
Behavioral and Ecological Correlates of Interference Competition among Some Hawaiian Drepanidinae
Authors: Carothers John H. 
Published: October 2019

Abstract
Interference interactions were studied on the island of Maui among four species of drepanidines that fed on canopy flowers of the ohia tree (Metrosideros collina). The birds had a size-related dominance hierarchy, with ranking (most to least dominant, by location in dominance matrix) as follows: Crested Honeycreeper (Palmeria dolei), Iiwi (Vestiaria coccinea), Apapane (Himatione sanguinea), and Common Amakihi (Hemignathus virens). Immatures were subordinate to conspecific adults. Crested Honeycreepers and Iiwis defended tree-canopy territories, Apapanes were nomadic flock foragers, and Common Amakihis were secretive foragers. Dominance by Iiwis was indicated by a lack of reversals in the dominance matrix. For the top-ranked Crested Honeycreeper dominance was also reflected in greater chase or greater resulting retreat distances or both. Age-related differences in interference behavior by dominants appeared to be due to inexperience, as indicated by shorter chase distances for immatures. Among subordinates both experience and plumage could be responsible for age differences in behavior. Immatures were chased equal distances (despite closer spacing) but less often than adults, and they chose safer retreat sites.
Apapanes fed in flocks in a dominant's tree. This increased a dominant's territorial costs, reduced chase frequencies, increased Apapane foraging times, and let Apapanes forage in trees from which they otherwise were excluded. Comparisons with the assemblage on the island of Hawaii suggested similar structure among the three species the two islands have in common. On Maui the bottom-ranked Common Amakihi may be more affected by interference competition, perhaps undergoing a niche shift toward greater insectivory because of an additional dominant.
Seabird Geographic Variation: Similarity Among Populations of Leach's Storm-Petrel
Authors: Power Dennis M. , Ainley David G. 
Published: October 2019

Abstract
We assessed geographic variation in 13 locality samples of Leach's Storm-Petrel (Oceanodroma leucorhoa), 12 from the Pacific coast and 1 from the Atlantic coast of North America. Nine phenetic characters were used with canonical variates analysis to determine similarity among samples. Regression of phenetic distance on geographic distance measured the relation between similarity and interisland distance. We found a clinal pattern of population similarity from the Aleutian Islands in the north to the Farallon Islands in the south. Populations from Los Coronados and San Benitos islands make up a distinct subset when rump color and wing and tail shape indices are included in the analysis, but these populations were part of a dominant clinal trend when only five size characters were used. On Guadalupe Island separate populations breed in summer and winter; these are strongly differentiated from the others and from each other. The North Atlantic sample was aligned closely with that from the Aleutians. The degree of geographic variation was roughly similar to that in certain migratory land birds on the North American continent, but is less than what is found for certain nonmigratory land birds on islands. Our results suggest recognizing four subspecies of Leach's Storm-Petrel in the study area, including two on Guadalupe Island isolated by time of breeding.
Sugar-Tasting Ability and Fruit Selection in Tropical Fruit-Eating Birds
Authors: Levey Douglas J. 
Published: October 2019

Abstract
The sugar-tasting abilities of four species of tanagers and two species of manakins were tested. Three tanager species were able to detect differences in diets containing 8%, 10%, and 12% sugar. In pairwise choice trials, they preferred the diet highest in sugar. Neither species of manakin discriminated among the three diets. This apparent difference in tasting abilities of tanagers and manakins may be a result of their fruit-handling techniques. Tanagers crush fruits in their bills, thereby releasing juices onto their tongues. Manakins swallow fruits whole; their tongues rarely encounter fruit juice. Hence, manakins' fruit-handling technique is poorly suited for sensing the taste cues in fruit juices. Variation in fruit sugar concentration is common within and among plant species and is great enough to be detected by birds. Birds probably have selected for sweeter fruits.
Energy Expenditure during Free Flight in Trained and Free-Living Eurasian Kestrels (Falco Tinnunculus)
Authors: Masman Dirkjan , Klaassen Marcel 
Published: October 2019

Abstract
During directional flight trained Eurasian Kestrels (Falco tinnunculus) in the laboratory expended 13.8 W. Free-living birds expended 14.6 W during nonsoaring flight that included both directional flight and wind hovering. The former value was obtained by combining food balance and indirect calorimetry techniques, the latter by doubly labeled water (Dz18O). Because the energy-expenditure rates are so similar for directional flight alone and for wind hovering and directional flight combined, we argue that the value for either mode of kestrel flight may be used to analyze time-energy budgets. We predicted avian flight costs (et) from an equation based on published data on flight costs in 14 species (body mass 3.8-1,000 g):

where M is body mass (g), bw is wing span (cm), and Sw is wing area (cm2). Inclusion of the morphological data with body mass significantly improved the prediction of flight cost [r2 = 0.84 vs. r2 = 0.75 without bw and sw, Fc (2,18) = 5.34, P < 0.05]. Received 8 May 1986, accepted 29 November 1986.
Cavity Roosting, Philopatry, and Cooperative Breeding in the Green Woodhoopoe May Reflect a Physiological Trait
Authors: Ligon J. David , Carey Cynthia , Ligon Sandra H. 
Published: October 2019

Abstract
Cooperative breeding in birds generally is related to a critical resource. A critical limiting factor for the Green Woodhoopoe (Phoeniculus purpureus) is the availability of roost cavities. Although predation at roost holes is the major source of mortality, woodhoopoes invariably roost in cavities or under loose bark. This dependence on cavities appears to be related to the birds' inability to cope physiologically with low nighttime temperatures. This is the first evidence to suggest that a physiological limitation has played a major role in the evolution of philopatry and possibly cooperative breeding in an avian species.