scholarly journals Feeding ecology of Auchenipterichthys longimanus (Siluriformes: Auchenipteridae) in a riparian flooded forest of Eastern Amazonia, Brazil

2011 ◽  
Vol 9 (3) ◽  
pp. 629-636 ◽  
Author(s):  
Tiago Magalhães da Silva Freitas ◽  
Vitor Hudson da Consolação Almeida ◽  
Roberta de Melo Valente ◽  
Luciano Fogaça de Assis Montag
Keyword(s):  
Amazon Basin ◽  
Diet Composition ◽  
Trophic Ecology ◽  
Feeding Habits ◽  
Biological Information ◽  
Adult Males ◽  
Terrestrial Invertebrates ◽  
Young Males ◽  
Young Females ◽  
Terrestrial Vertebrates

Feeding habits of the midnight catfish Auchenipterichthys longimanus collected in rivers of the Caxiuanã National Forest (Eastern Amazonia, Brazil) were investigated through the different hydrological periods (dry, filing, flood and drawdown). A total of 589 specimens were collected throughout seven samplings between July 2008 and July 2009, of which 74 were young males, 177 adult males, 89 young females and 249 adult females. The diet composition (Alimentary index - Ai%) was analyzed by a non-metric multidimensional scaling (nMDS) and by the analysis of similarity (ANOSIM), which included 37 items grouped into nine categories (Aquatic insects, Other aquatic invertebrates, Arthropods fragment, Fish, Plant fragment, Seeds, Terrestrial insects, Other terrestrial invertebrates, and Terrestrial vertebrates). We also calculated the niche breadth (Levins index) and the repletion index (RI%). Differences in the diet composition between hydrological seasons were registered, primarily on diet composition between dry and flood season, but changes related with sex and maturity were not observed. The midnight catfish showed more specialists feeder habit in the flood period (March 2009) and more generalist habits in the dry season (November 2008). The amount of food eaten by A. longimanus based on repletion index (RI%), did not differ significantly from sex and maturity. However, we evidenced differences in RI% when comparing the studied months. These results provide important biological information about the trophic ecology of auchenipterids fish. In view of the higher occurrence of allochthonous items, this research also underpins the importance of riparian forests as critical environments in the maintenance and conservation of wild populations of fish in the Amazon basin.

Effects of adults on survival and recruitment of Peromyscus leucopus

1987 ◽  
Vol 65 (10) ◽  
pp. 2519-2523
Author(s):  
Gregory H. Adler ◽  
Mark L. Wilson ◽  
Michael J. DeRosa
Keyword(s):  
Adult Female ◽  
Adult Male ◽  
Peromyscus Leucopus ◽  
Survival Rates ◽  
Adult Males ◽  
Control Grid ◽  
Young Males ◽  
Young Females ◽  
Breeding Seasons ◽  
And Control

A population of Peromyscus leucopus (white-footed mouse) in northeastern Massachusetts was manipulated for 3 years to determine the effects of adults on survival and recruitment. Two experimental grids were established, from which either all adult males or all adult females were removed continually. The effects of these two manipulations were compared with demography on a control grid. Manipulations had no apparent effect on breeding intensity of young, survival rates of adults, or residency rates of adults and young. Recruitment of adult males was higher on the adult male removal grid than on the control grid. Recruitment rates of adult males and of young males and young females were lower on the adult female removal grid than on the control grid. Survival rates of young males were higher on the adult female removal grid than on the control grid; this effect may have been due to either reduced adult female residency or adult male recruitment. All differences between experimental and control grids were noted only during breeding seasons. Adult males apparently limited recruitment of adult consexuals. The effects of manipulations on other measured parameters were inconclusive because of high immigration rates of adult males onto the adult male removal grid and reduced recruitment of adult males and decreased production of young on the adult female removal grid.

scholarly journals Reproductive seasonality, sex ratio and philopatry in Argentina's common vampire bats

2017 ◽  
Vol 4 (4) ◽  
pp. 160959 ◽  
Author(s):  
H. A. Delpietro ◽  
R. G. Russo ◽  
G. G. Carter ◽  
R. D. Lord ◽  
G. L. Delpietro
Keyword(s):  
Specific Information ◽  
Adult Males ◽  
Reproductive Seasonality ◽  
Tropical Regions ◽  
Young Males ◽  
Young Females ◽  
Vampire Bats ◽  
Lactating Females ◽  
Free Ranging

Common vampire bats ( Desmodus rotundus ) are a key rabies vector in South America. Improved management of this species requires long-term, region-specific information. To investigate patterns of demography and dispersal, we analysed 13 642 captures of common vampire bats in Northern Argentina from the period 1969–2004. In contrast with findings from more tropical regions, we found reproductive seasonality with peak pregnancy in September and peak lactation in February. Curiously, sex ratios were consistently male-biased both in maternity roosts and at foraging sites. Males comprised 57% of 9509 adults caught at night, 57% of 1078 juveniles caught at night, 57% of 603 juveniles caught in roosts during the day, and 55% of 103 newborns and mature fetuses. Most observed roosts were in man-made structures. Movements of 1.5–54 km were most frequent in adult males, followed by young males, adult females and young females. At night, males visited maternity roosts, and non-pregnant, non-lactating females visited bachelor roosts. Males fed earlier in the night. Finally, we report new longevity records for free-ranging vampire bats: 16 and 17 years of age for a female and male, respectively. Our results are consistent with model predictions that sex-biased movements might play a key role in rabies transmission between vampire bat populations.

Factors Affecting the Distribution of Mallards Wintering in the Mississippi Alluvial Valley

The Auk ◽  
1983 ◽  
Vol 100 (4) ◽  
pp. 932-946 ◽  
Author(s):  
James D. Nichols ◽  
Kenneth J. Reinecke ◽  
James E. Hines
Keyword(s):  
Population Size ◽  
Mississippi Alluvial Valley ◽  
Adult Males ◽  
Alluvial Valley ◽  
Factors Affecting ◽  
Young Males ◽  
Young Females ◽  
Winter Distribution ◽  
Wintering Areas ◽  
Males And Females

Abstract The Mississippi Alluvial Valley (MAV) is the principal wintering area for Mallards (Anas platyrhynchos) in the Mississippi Flyway. Here, we consider it a distinct habitat (sensu Fretwell 1972), i.e. fitness is relatively homogeneous among ducks within the MAV but different from that of ducks in other such habitats. We analyzed recovery distributions of Mallards banded preseason (July-September 1950-1980) to test hypotheses concerning the effects of winter temperatures, precipitation, and population levels on Mallard winter distribution. When two groups of years that comprised extremes of warm and cold winter weather were compared, recovery distributions of all four age and sex classes (adult males and females, young males and females) differed significantly; recoveries were located farther south in cold years. Recovery distributions also differed between wet and dry years in the MAV for all groups except adult males, higher proportions of recoveries of adult females and of young males and females occurring in the MAV during wet winters. Although differences in continental Mallard population size were associated with differences in recovery distributions only of adult males and young females, the proportion of young males and of all young Mallards recovered in the MAV increased during years of low populations. We conclude that temperature, water conditions, and population size affect the habitat suitability of Mallard wintering areas and that Mallards exhibit considerable flexibility in winter distribution associated with these factors.

Benefits, Costs, and Determinants of Dominance in American Black Ducks

Behaviour ◽  
1989 ◽  
Vol 109 (3-4) ◽  
pp. 222-234 ◽  
Author(s):  
Gary R. Hepp
Keyword(s):  
Body Mass ◽  
Dominance Rank ◽  
Positive Association ◽  
Adult Males ◽  
Restricted Diet ◽  
Significant Positive Association ◽  
Young Males ◽  
Young Females ◽  
American Black ◽  
Ad Libitum

AbstractBehavioural dominance was studied in captive American black ducks (Anas rubripes) during October-December 1984. Eighty ducks were marked individually, and groups of 10 ducks consisting of 5 adults (3 males and 2 females) and 5 juveniles (3 males and 2 females) were assigned to each of 8 experimental pens. Ducks in 4 pens received an ad libitum diet, and ducks in the other 4 pens were given a restricted diet. Dominance structure within pens was linear. Adults were dominant to young, and body mass had no influence on dominance rank. The effect of sex on dominance rank was age-specific. Adult males were dominant to adult females and to young black ducks of both sexes; however, dominance rank of young males did not differ from adult or young females. Paired adults were dominant to unpaired adults and to young individuals that were either paired or unpaired. Paired young black ducks were similar in dominance rank to unpaired adults and unpaired young indicating that pairing did not make these individuals more dominant. Ducks on the restricted diet gained less body mass than ducks on the ad libitum diet (HEPP, 1986), but dominant and subordinate black ducks within treatment groups experienced similar changes in body mass during the early winter. Dominant black ducks interacted more frequently and were more likely to form pair bonds than subordinates, thus higher energy costs of dominant individuals may explain the poor relationship between physical condition and dominance rank. There was a significant positive association between the dominance ranks of pair members.

scholarly journals Diet composition of Plagioscion squamosissimus (Heckel, 1840), a fish introduced into the Tietê River system

2009 ◽  
Vol 69 (3) ◽  
pp. 805-812 ◽  
Author(s):  
PM. Stefani ◽  
O. Rocha
Keyword(s):  
Aquatic Insects ◽  
Amazon Basin ◽  
Diet Composition ◽  
Feeding Habits ◽  
River System ◽  
Similarity Coefficient ◽  
Feeding Habit ◽  
Ontogenetic Changes ◽  
Taxonomic Level ◽  
Tietê River

Plagioscion squamosissimus is a species from the Amazon basin that was introduced into the Tietê River system. The present study aimed to analyse the feeding habits of this species in Bariri Reservoir and to verify the possible occurrence of ontogenetic changes in its diet composition. The samples were gathered in four periods of the year: February, June, September and November 2003. The fish were gathered with different fishing net meshes in three different reservoir portions. The alimentary items found in the stomachs were identified to the lowest possible taxonomic level and had abundance, occurrence frequency, volume and biomass determined. The Alimentary Index (IAi) was calculated for each alimentary item consumed by "corvina" for each studied period. Comparisons among the diet of different size classes of P. squamosissimus were done using the similarity coefficient of Jaccard and the Cluster Analysis (UPGMA). The Friedman proof was performed to verify if there is a significant ontogenetic variation in the species diet and changes in the consumption of different alimentary categories by P. squamosissimus among the sampled periods. P. squamosissimus presented a piscivorous feeding habit, although other items were also consumed. The biggest values of IAi were obtained for the alimentary item fish in the months of June (0.47) and November (0.39). The item Ephemeroptera (Campsurinae) was the most representative in February (0.30) and June (0.45). Despite the fact that P. squamosissimus consumed an ample spectrum of alimentary items, the ontogenetic changes were evident through the exploration of aquatic insects by the younger classes and by a diet mainly composed of fish in adult individuals. The alimentary plasticity of P. squamosissimus evidenced in this study might have contributed to the success of this species in Bariri Reservoir.

A Previously Unknown Plumage of First-Year Indigo Buntings and Theories of Delayed Plumage Maturation

The Auk ◽  
1986 ◽  
Vol 103 (2) ◽  
pp. 281-292 ◽  
Author(s):  
Sievert Rohwer
Keyword(s):  
The United States ◽  
The Body ◽  
First Year ◽  
Adult Males ◽  
Young Males ◽  
Young Females ◽  
Female Mimicry ◽  
Breeding Plumage ◽  
Almost All ◽  
Wintering Ground

Abstract First-year, but not adult, Indigo Buntings (Passerina cyanea) have a previously unknown supplemental plumage. The presupplemental molt includes all of the rectrices, the outermost but not the innermost primaries, and, typically, the three innermost secondaries and all body feathers. In this molt, young females exchange one adult-femalelike plumage for another, while young males exchange an adult-femalelike plumage for one that matches that of adult males in winter. Thus, in their first year Indigo Buntings wear: first, the juvenile plumage, the body feathers of which begin replacement before the tail is fully grown; second, the first basic plumage, which in both sexes is entirely femalelike in coloration and includes the juvenile remiges and rectrices; third, the supplemental plumage, assumed either prior to fall migration (<10% of individuals) or on the wintering ground (>90% of individuals) and in which obvious sexual dichromatism is first achieved; and fourth, the first alternate plumage, acquired in a prolonged and often incomplete prealternate molt of body feathers that occurs during February, March, and April on the wintering ground and during the spring in the United States. Because almost all of the femalelike first basic plumage of young males is lost in the presupplemental molt, this plumage almost certainly is an adaptation to conditions encountered either in the fall or early in the first winter. Furthermore, the ensuing supplemental plumage cannot be compromised by color requirements of the first breeding season because of the intervening prealternate molt; thus, the adult-malelike plumage produced by the presupplemental molt likely evolved to meet a change in signaling requirements that occurs in early winter. The signaling function of this plumage is unknown. Because this supplemental plumage of young males resembles the winter plumage of adult males and because all feathers grown by young males in their first prealternate molt resemble those of the adult male breeding plumage, the female mimicry hypothesis of Rohwer et al. (1980) is untenable for the subadult breeding plumage of yearling male Indigo Buntings.

scholarly journals POLA PENGGUNAAN RUANG DAN WAKTU RUSA SAMBAR (Rusa unicolor) DI RAGUNAN

2021 ◽  
Vol 1 (3) ◽  
pp. 129-135
Author(s):  
Julaili Irni
Keyword(s):  
Time Use ◽  
Time Allocation ◽  
Time Budget ◽  
Daily Activities ◽  
Adult Males ◽  
Young Males ◽  
Young Females ◽  
Age Class ◽  
Allocation Of Time ◽  
Sambar Deer

Daily activities are all activities carried out by animals daily starting from the morning out of the nest until late in the evening and back again to the nest. This study aims to determine the activity pattern of sambar deer (Rusa unicolor). This observation was carried out at the Ragunan zoo which was carried out in 3 stages, namely morning, afternoon and evening. This study observed the patterns of time use and space use observed in sambar deer with 5 age class categories, namely adult males, adult females, young males and young females. The results of the research obtained from the activity of the sambar deer in the morning, namely the allocation of time for daily activities in the morning for each different age class, the allocation of time for feeding, moving, and resting activities during the daytime period for each individual age class of the deer is different and the time allocation for daily activities in the afternoon for each age class is different. Most of the sambar deer in Ragunan prefer to be in the grass below the stands for their activities. Time allocation (time budget) for sambar deer in age class and sex is influenced by the time of activity (morning-afternoon-evening).

Evidence for male-biased dispersal in a reintroduced population of burrowing bettongs Bettongia lesueur at Heirisson Prong, Western Australia.

2002 ◽  
Vol 24 (2) ◽  
pp. 219 ◽  
Author(s):  
BC Parsons ◽  
JC Short ◽  
MC Calver
Keyword(s):  
Western Australia ◽  
Radio Telemetry ◽  
Adult Males ◽  
Resource Quality ◽  
Young Males ◽  
Young Females ◽  
Shark Bay ◽  
Mating Opportunities ◽  
Reintroduced Population ◽  
Dispersal Distances

The pattern of dispersal of burrowing bettongs (Bettongia lesueur) was studied in a population reintroduced to a peninsula protected from exotic predators at Heirisson Prong in Shark Bay, Western Australia. The reintroduced population was growing strongly in numbers and expanding in area during the study. Young were first marked in the pouch and subsequently monitored by trapping and radio-telemetry after independence to establish their movements relative to those of their mothers. B. lesueur on Heirisson Prong dispersed between the ages of 170 and 250 days, coinciding with the period from weaning to sexual maturity. Dispersal was male-biased. Young males dispersed significantly further than young females with mean dispersal distances of 4600 m and 1100 m respectively. Male B. lesueur also frequented significantly more warrens than females, being located at a mean of 0.37 warrens per daily radio-tracking fix compared with a mean of 0.24 per fix for females. Scarring from intraspecific aggression occurred in male bettongs only. Males may disperse to the periphery of the population to escape aggressive interactions with established adult males and visit more warrens to increase mating opportunities. Dispersal in females may be related to resource quality or inbreeding avoidance.

Comparative assessment of average clinical smile parameters in male and female patients with orthognathic occlusion

2020 ◽  
Vol 25 (2) ◽  
pp. 121-126
Author(s):  
V. G. Galonsky ◽  
N. V. Tarasova ◽  
V. V. Aliamovskii ◽  
I. S. Leonovich
Keyword(s):  
Sexual Dimorphism ◽  
Male And Female ◽  
Young Males ◽  
Young Females ◽  
Female Patients ◽  
Evaluation Of Parameters ◽  
Distinguishing Features ◽  
Vertical Size ◽  
Relative Concept ◽  
The Ideal

Relevance. Separate issues in anthropomorphic sizes of relative norm of the ideal smile, its qualitative and qualitative parameters have not been addressed to sufficiently and are not properly reflected in scientific literature.Purpose. To determine distinguishing features in average smile parameters of the smile in male and female patients with orthognathic occlusion.Materials and methods. A clinical and anthropometric evaluation of parameters in main smile types was carried out for 150 young males and 150 young females aged 19-24 who had identical physiological development parameters.Results. It has been revealed that occurrence frequency of main smile types in patients with orthognathic occlusion has pronounced signs of sexual dimorphism which in over one half of the cases lies in predominance of the incisal smile type in males (52.7%) and the fascial type in females (55.3%). Occurence frequency of the cervical smile type totaled 25% among the studied patients of both genders. Average vertical size parameters in the incisal smile lies within the diapason of 3.91-4.91mm with surpassing by 1mm in males. Analogical data for the fascial smile type form the diapason of 6.21-6.73mm with surpassing by 0.52mm in females. The cervical smile type is characterised by larger vertical size forming the diapason of 7.94-8.91mm with surpassing by 0.97mm in males.Conclusion. The results of the study have shown that the “beautiful and ideal smile” is a relative concept having varied anthropometric characteristics and pronounced signs of sexual dimorphism lying in a broad spectrum of the dentofacial system norm notion with specific vectors for individual morphological deviations.

scholarly journals Correlates and Treatment Outcome of Risky Sexual Behaviour in Young Males with ADHD and Comorbid Alcohol Use Disorder: A Prospective Study

2019 ◽  
Vol 1 (1) ◽  
pp. 62-69
Author(s):  
Shankar Kumar ◽  
Yamini Devendran ◽  
Madhumitha N. S. ◽  
Javagal Amith Thejas
Keyword(s):  
Sexual Behavior ◽  
Alcohol Use ◽  
Perceived Stress ◽  
Risky Sexual Behavior ◽  
Alcohol Use Disorder ◽  
Self Report ◽  
Adult Males ◽  
Young Males ◽  
Severity Scores ◽  
Inattention And Hyperactivity

Background: Attention-deficit/hyperactivity disorder (ADHD) is associated with risky sexual behavior (RSB). Alcohol use and high perceived stress in young adulthood contributes to this association. Previous studies have not found methylphenidate to reduce RSB in ADHD, as the population had comorbidities such as mood disorders and antisocial personality disorder. We aimed to study (a) the association of RSB with ADHD and severity of alcohol use among adolescents and young adult males with ADHD who had comorbid alcohol use disorder and (b) the effect of treatment of ADHD using methylphenidate on RSB in this population at 3- and 6-month follow-ups. Methodology: The study had 31 participants who were selected by screening for RSBs using the sexual behavior section of the HIV Risk-taking Behavior Scale (HRBS) manual among a cohort of individuals with ADHD and early onset alcohol use. These individuals were also administered WHO ADHD self-report scale (ASRS), alcohol-use disorders identification test (AUDIT), perceived stress scale (PSS), and HRBS-sexual behavior section. They were then treated with methylphenidate and these assessments were repeated at 3 and 6 months. Results: Those having ADHD with RSB had higher total ADHD score ( P = .007) and inattention score ( p = .0001) than those without RSB. There was a significant correlation between the ADHD total score with alcohol-use severity ( r = 0.47), with RSB ( r = 0.34), and ADHD hyperactivity scores with alcohol-use severity ( r = 0.49) and with RSB ( r = 0.34). There was also a significant reduction of ADHD total, inattention and hyperactivity scores, alcohol-use severity scores, RSB and perceived stress scores with use of methylphenidate at 3- and 6-month follow-ups. Multiple logistic regression predicted reduction in ADHD total scores to reduce RSB (odds ratio [OR] = 1.26, P = .01). Conclusion: RSB was associated with severity of ADHD and alcohol use. Methylphenidate not only reduced ADHD severity but also alcohol-use severity and RSB, whose reduction was predicted by reduction in ADHD severity.

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