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1. The optimum dose and period of 17α-methyltestosterone immersion on masculinization of red tilapia (Oreochromis spp.)

Author:
Thuchapol Karaket; Aisawan Reungkhajorn; Pattareeya Ponza
Source:
Aquaculture and fisheries 2023 v.8 no.2 pp. 174-179
ISSN:
2468-550X
Subject:
sex ratio,   etc   ; Oreochromis; aquaculture; fish; glass; males; masculinization; survival rate;     Show all 8 Subjects
Abstract:
... This study was carried out to examine the effect of combining factors for immersion technique on masculinization of red tilapia (Oreochromis spp.). Three selected doses (1000, 1,500, and 2000 μg/L) of 17α-methyltestosterone (17 MT) immersion, 2 exposure times (3 and 6 h) once or twice a week, and interaction of these factors were tested. A total of 12 treatment combinations under 3 × 2 × 2 factori ...
DOI:
10.1016/j.aaf.2021.09.001

2. Reproductive biology of largehead hairtail (Trichiurus lepturus) in south-eastern Australia

Author:
Chantelle Clain; John Stewart; Ashley Fowler; Sandra Diamond
Source:
Aquaculture and fisheries 2023 v.8 no.2 pp. 148-158
ISSN:
2468-550X
Subject:
sex ratio,   etc   ; Trichiurus lepturus; aquaculture; estuaries; females; genetic variation; habitats; histology; life history; males; temperature; winter; Australia;     Show all 13 Subjects
Abstract:
... Knowledge of reproductive biology and life-history traits of populations exploited by fisheries is important for their sustainable management. We investigated the life-history traits of Trichiurus lepturus (largehead hairtail) in south-eastern Australia; a region of low exploitation for this otherwise heavily exploited circumglobal species, to investigate whether there were differences in the repr ...
DOI:
10.1016/j.aaf.2021.09.008

3. Estimation of Population Size and Sex Ratio of Ryukyu Scops Owl Otus elegans on Hateruma Island

Author:
Akira Sawada
Source:
Ornithological science 2022 v.21 no.2 pp. 245-251
ISSN:
1347-0558
Subject:
sex ratio,   etc   ; Otus; mark-recapture studies; models; population size;     Show all 5 Subjects
Abstract:
... Fundamental demographic data of insular populations of Otus owls are not available for most species. This study investigated the population size and the sex ratio of the Ryukyu Scops Owls Otus elegans on Hateruma Island. Capture-recapture data was obtained by intensive marking and route census surveys from July to September in 2021. Analysing the data using a site-occupancy model combined with a d ...
DOI:
10.2326/osj.21.245

4. Temperature-Specific and Sex-Specific Fitness Effects of Sympatric Mitochondrial and Mito-Nuclear Variation in Drosophila obscura

Author:
Pavle Erić; Aleksandra Patenković; Katarina Erić; Marija Tanasković; Slobodan Davidović; Mina Rakić; Marija Savić Veselinović; Marina Stamenković-Radak; Mihailo Jelić
Source:
Insects 2022 v.13 no.2 pp. -
ISSN:
2075-4450
Subject:
sex ratio,   etc   ; Drosophila obscura; genome; haplotypes; mitochondria; sympatry; temperature; viability;     Show all 8 Subjects
Abstract:
... The adaptive significance of sympatric mitochondrial (mtDNA) variation and the role of selective mechanisms that maintain it are debated to this day. Isofemale lines of Drosophila obscura collected from four populations were backcrossed within populations to construct experimental lines, with all combinations of mtDNA Cyt b haplotypes and nuclear genetic backgrounds (nuDNA). Individuals of both se ...
DOI:
10.3390/insects13020139

5. Bateman gradients reflect variation in sexual selection in a species with dynamic sex roles

Author:
Robin M. Hare; Leigh W. Simmons
Source:
Journal of evolutionary biology 2022 v.35 no.9 pp. 1206-1217
ISSN:
1010-061X
Subject:
sex ratio,   etc   ; Tettigoniidae; females; pollen; reproductive success; sexual selection; spermatophores;     Show all 7 Subjects
Abstract:
... Bateman gradients, the slope of the regression of reproductive success on mating success, are among the most commonly reported measures of sexual selection. They are particularly insightful in species with reversed sex roles, where females are expected to be under sexual selection. We measured Bateman gradients in replicate experimental populations of the spermatophore gift‐giving bushcricket Kawa ...
DOI:
10.1111/jeb.14070

6. Biological traits and field distribution of introduced Arhopalus species in Central Argentina

Author:
Romina Fachinetti; Mariano Pablo Grilli
Source:
International journal of pest management 2022 v.68 no.3 pp. 274-284
ISSN:
1366-5863
Subject:
sex ratio,   etc   ; Arhopalus rusticus; forest management; instars; larvae; pest management; Argentina;     Show all 7 Subjects
Abstract:
... Arhopalus rusticus rusticus and Arhopalus syriacus (Coleoptera: Cerambycidae) are exotic forestry pests that coexist in Córdoba (Argentina). To contribute to forest management strategies, we examined how their emergence, development, and abundance affect the sex ratio. We found a dispersal sex ratio of 0.5:0.5 (males:females) in both species. The birth sex ratio was 0.5:0.5 in A. syriacus and 0.6: ...
DOI:
10.1080/09670874.2020.1818871

7. New records of the not-so-rare males of the parthenogenetic scorpion Tityus stigmurus (Thorell, 1876) (Scorpiones: Buthidae)

Author:
Stenio Italo Araujo Foerster; Welton Dionisio-da-Silva; Adriana Barbosa dos Santos; Cleide Maria Ribeiro de Albuquerque; André Felipe de Araujo Lira
Source:
Journal of arachnology 2022 v.50 no.1 pp. 27-29
ISSN:
0161-8202
Subject:
sex ratio,   etc   ; Tityus; geographical distribution; natural history; parthenogenesis; ultraviolet radiation; Brazil;     Show all 7 Subjects
Abstract:
... Parthenogenesis and sex-ratio bias may lead to erroneous assumptions concerning the natural history of some arachnids. To help address this issue, this study provides new data on the sex ratio and geographic distribution of sexual populations of the scorpion Tityus stigmurus (Thorell, 1876). Ultraviolet light lanterns were used to detect specimens during nocturnal searches performed in both urban ...
DOI:
10.1636/JoA-S-21-009

8. Ecology and behavior of the troglobitic harvestman Jimeneziella decui Avram, 1970 (Arachnida: Opiliones)

Author:
Aylin Alegre Barroso; René Barba Díaz; Germán M. López Iborra
Source:
Journal of arachnology 2022 v.50 no.1 pp. 101-112
ISSN:
0161-8202
Subject:
sex ratio,   etc   ; Opiliones; Perla; ecology; endangered species; females; femur; males; Cuba;     Show all 9 Subjects
Abstract:
... The troglobitic harvestman Jimeneziella decuiAvram, 1970 is known from four neighboring caves (Cueva de Majana, Cueva de los Golondrinos, Cueva Perla del Agua, and Cueva de Máximo) located in eastern Cuba. We present the first ecological data on a population of this endangered species in Cueva de Máximo. The sex ratio of the population estimated in the main gallery of the cave was not different fr ...
DOI:
10.1636/JoA-S-20-089

9. The Reintroduction Analysis of European Bison (Bison bonasus L., 1758) in the North of Romania and the Identification of the Most Favourable Locations

Author:
Gabriel Dănilă; Sebastian Cătănoiu; Valerian Simioniuc; Sanda Roșca
Source:
Forests 2022 v.13 no.6 pp. -
ISSN:
1999-4907
Subject:
sex ratio,   etc   ; Bison bonasus; extinction; fauna; genetic improvement; periodicity; risk; Romania;     Show all 8 Subjects
Abstract:
... We analysed the possibility of reintroducing the European bison (Bison bonasus L.) in the north of Romania—in Suceava, Neamț, and Maramureș counties—as well as increasing the wild European bison population in Neamț county to improve the genetic quality of the existing population. Currently, there is a population of over 50 individuals in the wild in Vânători Neamț Natural Park, Romania. At the sam ...
DOI:
10.3390/f13060920

10. Age and growth of the Cape knifejaw Oplegnathus conwayi, an endemic South African teleost

Author:
RM Foster; A-R Childs; BQ Mann; WM Potts
Source:
African zoology 2022 v.57 no.1 pp. 1-11
ISSN:
2224-073X
Subject:
sex ratio,   etc   ; Oplegnathus; females; growth curves; males; population growth; zoology; South Africa;     Show all 8 Subjects
Abstract:
... The South African spearfishery targets a variety of data-deficient species, which are consequently poorly managed. This study aimed to describe the age and growth of one of these species, the Cape knifejaw, Oplegnathus conwayi, which is endemic to the southern and eastern coasts of South Africa. Monthly biological samples were collected through research spearfishing (n = 170) and augmented by recr ...
DOI:
10.1080/15627020.2022.2035254

11. Effect of parent flock age on hatching, growth rate, and features of both sexes goose carcasses

Author:
Joanna Kucharska-Gaca; Marek Adamski; Jakub Biesek
Source:
Poultry science 2022 v.101 no.8 pp. 101920
ISSN:
0032-5791
Subject:
sex ratio,   etc   ; abdominal fat; body weight; dissection; flocks; muscles; oats; slaughter; waterfowl;     Show all 9 Subjects
Abstract:
... The study aimed to assess the hatchability of goslings from parent flocks of geese in 4 laying seasons and to analyze the growth, carcass, and muscles characteristics. The hatching eggs from the White Kołuda geese from the 1st to 4th laying season were incubated by the waterfowl hatching technology. Hatchability rates were calculated. 40 goslings were selected from each group. The geese were reare ...
DOI:
10.1016/j.psj.2022.101920

12. Rare occurrences of polygyny in the monogamous Florida Scrub-Jay (Aphelocoma coerulescens): Synthesis of 97 combined years of population monitoring across 3 populations

Author:
Rebecca L. Windsor; Angela Tringali; Michelle Dent; Reed Bowman
Source:
Wilson journal of ornithology 2022 v.133 no.3 pp. 484-490
ISSN:
1559-4491
Subject:
sex ratio,   etc   ; Aphelocoma coerulescens; females; landscapes; monogamy; ornithology; polygyny; reproductive performance; wildland;     Show all 9 Subjects
Abstract:
... Polygamy is common in many taxa, particularly birds. Several hypotheses support evolutionary or ecological explanations for the presence of polygamous mating systems, but these may not explain rare occurrences of polygamy in predominantly monogamous systems. We identified 12 cases of polygyny in 3 populations of varying landscape structure (contiguous wildlands, fragmented wildlands, and suburban) ...
DOI:
10.1676/20-00070

13. Thermal reaction norm for sexualization: The missing link between temperature and sex ratio for temperature-dependent sex determination

Author:
Jonathan R. Monsinjon; Jean-Michel Guillon; Jeanette Wyneken; Marc Girondot
Source:
Ecological modelling 2022 v.473 pp. 110119
ISSN:
0304-3800
Subject:
sex ratio,   etc   ; Caretta caretta; climate change; feminization; masculinization; prediction; sex determination; temperature;     Show all 8 Subjects
Abstract:
... Species with temperature-dependent sex determination (TSD) can experience biased sex ratios in natural conditions, which raises questions the vulnerability of populations in the face of climate change. Studies addressing the adaptive significance TSD have been hampered by the difficulty of accurately estimating sex ratios under natural incubation conditions. Here we introduce the thermal reaction ...
DOI:
10.1016/j.ecolmodel.2022.110119

14. Catch composition of mobulid rays (Mobula spp.) in northern Peru reveals a potential nursery area for M. mobular

Author:
Adriana González-Pestana
Source:
Environmental biology of fishes 2022 v.105 no.7 pp. 963-969
ISSN:
0378-1909
Subject:
sex ratio,   etc   ; Mobula; body size; catch composition; fisheries; habitats; immatures; stakeholders; Peru;     Show all 9 Subjects
Abstract:
... Peru presents an important habitat and fishery area for mobulid rays in the Eastern Pacific in which five mobulid species interact with fisheries. Yet, management is weak and species-specific fishery information is limited for this group. Therefore, this study describes species, body size, and sex composition of mobulid rays caught by small-scale fisheries in northern Peru at four landing points. ...
DOI:
10.1007/s10641-022-01301-0

15. Inter-sexual differences in contributions of helpers in a tropical population of the cooperatively breeding Grey-crowned Babbler Pomatostomus temporalis

Author:
Kazuhiro Eguchi; Katsura Mikami; Noriyuki Yamaguchi; Richard A. Noske
Source:
Emu 2022 v.122 no.2 pp. 77-86
ISSN:
1448-5540
Subject:
sex ratio,   etc   ; emus; females; group size; kin selection; males; nests; philopatry; progeny;     Show all 9 Subjects
Abstract:
... The Grey-crowned Babbler Pomatostomus temporalis is a group-living, cooperatively breeding species in which offspring of both sexes are equally philopatric, but only male helpers inherit the natal territory. We quantified helping efforts in a tropical population of the babbler, and tested the hypothesis that inter-sexual differences in helping efforts are related to the chance of inheriting their ...
DOI:
10.1080/01584197.2022.2072347

16. A Test of Deriving Sex‐Composition Data for the Directed Pacific Halibut Fishery via At‐Sea Marking

Author:
Timothy Loher; Orion McCarthy; Lauri L. Sadorus; Lara M. Erikson; Anna Simeon; Daniel P. Drinan; Lorenz Hauser; Josep V. Planas; Ian J. Stewart
Source:
Marine and coastal fisheries 2022 v.14 no.4 pp. e10218
ISSN:
1942-5120
Subject:
sex ratio,   etc   ; Hippoglossus stenolepis; data quality; fins; fish; fisheries; outreach; uncertainty; variance;     Show all 9 Subjects
Abstract:
... Sensitivity analyses have identified uncertainty regarding sex ratios within commercial landings of Pacific Halibut Hippoglossus stenolepis as an influential source of variance within annual stock assessments for this species in U.S. and Canadian waters. Sex composition of dockside landings cannot be directly observed because all retained fish must be eviscerated at sea, and sex cannot be visually ...
DOI:
10.1002/mcf2.10218

17. Local male breeding density affects extra‐pair paternity in a south temperate population of grass wrens Cistothorus platensis

Author:
Ramiro S. Arrieta; Leonardo Campagna; Bettina Mahler; Irby Lovette; Paulo E. Llambías
Source:
Journal of avian biology 2022 v.2022 no.4 pp. e02887
ISSN:
0908-8857
Subject:
sex ratio,   etc   ; Cistothorus; adults; genotyping; grasses; males; nests; paternity; progeny; space and time;     Show all 10 Subjects
Abstract:
... Demographic factors can affect the frequency of extra‐pair paternity (EPP) in birds, as the distribution and availability of potential mates in both space and time influence the rate of encounters between females and males. Over three breeding seasons, we intensively studied the breeding system of a south temperate population of grass wrens Cistothorus platensis by genotyping 73 broods (319 nestli ...
DOI:
10.1111/jav.02887

18. Performance of Ferrolure+ pheromone in the red palm weevil, Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) management in date palm growing areas of Sindh, Pakistan

Author:
Mushtaq Hussain Soomro; Jan Muhammad Mari; Imtiaz Ahmed Nizamani; Arfan Ahmed Gilal
Source:
Journal of the Saudi Society of Agricultural Sciences 2022 v.21 no.2 pp. 114-124
ISSN:
1658-077X
Subject:
sex ratio,   etc   ; Phoenix dactylifera; Rhynchophorus ferrugineus; hibernation; relative humidity; temperature; Costa Rica; Pakistan;     Show all 8 Subjects
Abstract:
... Red palm weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) has caused huge losses to date palm in Sindh province, main producer of dates in Pakistan. Due to lack of knowledge and availability regarding aggregation pheromones, mainly pesticides are used for its management. Therefore, seasonal monitoring of RPW was conducted at five talukas of Khairpur (Khairpur, KIngri, Kot Diji) ...
DOI:
10.1016/j.jssas.2021.07.004

19. Pollinating fig wasps’ simple solutions to complex sex ratio problems: a review

Author:
Jaco M. Greeff; Finn Kjellberg
Source:
Frontiers in zoology 2022 v.19 no.1 pp. 3
ISSN:
1742-9994
Subject:
sex ratio,   etc   ; eggs; females; figs; males; mating competitiveness; mortality; natural selection; oviposition; wasps;     Show all 10 Subjects
Abstract:
... Local mate competition (LMC) favours female biased clutch sex ratios because it reduces competition between brothers and provides extra mating opportunities for sons. Fig wasps seem to fit LMC model assumptions and lay female-biased sex ratios as predicted. These female biased sex ratios increase fitness greatly. In line with predictions, their sex ratios become less female-biased as the number of ...
DOI:
10.1186/s12983-021-00447-4

20. Management of Centris analis (Hymenoptera: Apidae): Investigating the Ideal Dimensions of Trap Nests for Use in Crop Pollination

Author:
Geoge Carlos Vieira; Paulo Fellipe Cristaldo; Daniele Regina Parizotto
Source:
Neotropical entomology 2022 v.51 no.3 pp. 397-403
ISSN:
1678-8052
Subject:
sex ratio,   etc   ; Apidae; Centris; Neotropics; bees; entomology; females; mortality; nests; parasitism; pollination; pollinators;     Show all 12 Subjects
Abstract:
... Centris analis (Fabricius, 1804) is a solitary, cavity-nesting bee that is often recorded in studies through the use of trap nests. This species is considered to be a good candidate as a manageable pollinator for some orchards. However, further studies are still needed to optimize its rational rearing. This study sought to analyze female preference for different lengths and diameters of trap nests ...
DOI:
10.1007/s13744-022-00959-6