Influences of age, body condition, and structural size on mate selection by dabbling ducks

1995 ◽  
Vol 73 (12) ◽  
pp. 2251-2258 ◽  
Author(s):  
Mickey E. Heitmeyer
Keyword(s):  
Assortative Mating ◽  
Body Condition ◽  
Mate Selection ◽  
Reproductive Potential ◽  
The Body ◽  
Dabbling Ducks ◽  
Structural Size ◽  
Nutrient Reserve ◽  
Anas Clypeata ◽  
Similar Body

Both members of pairs of mallards (Anas platyrhynchos), northern pintails (Anas acuta), northern shovelers (Anas clypeata), and American wigeon (Anas americana) were collected early in the pairing periods in fall and during spring migration (several months after most birds were paired) to provide insights into whether (i) assortative mating occurs; (ii) body condition changes synchronously among pair members; and (iii) characteristics of selected individuals ultimately confer advantages in survival and recruitment. Both members in 19 of 21 mallard, 16 of 16 pintail, 14 of 14 shoveler, and 14 of 15 wigeon pairs were adults. The predominance of adults in pairs in fall indicates that adults pair earlier than juveniles and suggests at least some assortative mating in relation to age. Generally, body and nutrient reserve masses of males and females within a pair were correlated for all species in both fall and spring, suggesting that individuals tend to form pairs with others of relatively similar body condition, and also that once paired, the body condition of the two members tends to change at the same time. In contrast to body condition, measures of structural size of pair members were not correlated. Field data suggest that older and heavier ducks have greater survival and reproductive potential than young, lighter ducks; consequently, selection of old and heavy mates is probably evolutionarily advantageous.

Phenotypic assortative mating and within-pair sexual dimorphism and its influence on breeding success and offspring quality in Magellanic penguins

2001 ◽  
Vol 79 (8) ◽  
pp. 1414-1422 ◽  
Author(s):  
M G Forero ◽  
J L Tella ◽  
J A Donázar ◽  
G Blanco ◽  
M Bertellotti ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
Assortative Mating ◽  
Body Mass ◽  
Body Condition ◽  
Relative Difference ◽  
The Body ◽  
Phenotypic Traits ◽  
Magellanic Penguins ◽  
Patagonian Coast ◽  
Potential Factors

We examined within-pair sexual dimorphism and phenotypic assortative mating in Magellanic penguins (Spheniscus magellanicus) breeding in six colonies located on the Patagonian coast (Argentina). All measured phenotypic traits except the number of pectoral spots differed between the sexes; bill depth and flipper length were the most and least dimorphic traits, respectively. We found assortative mating by bill depth and body mass. The similarity in body condition within pairs was close to significant. When we performed separate correlations for birds that bred successfully, i.e., raised one or two offsprings, and birds that did not attempt to breed or bred unsuccessfully, only the successful breeders showed assortative mating by body mass. In addition, we attempted to relate the body size of each member of the pair and the degree of sexual dimorphism within pairs to the breeding performance of individuals, which was measured as brood size, and body condition and immunocompetence of offspring. We found that pairs that were less dimorphic in flipper length raised more offspring. This effect was due to female flipper length per se and not to the relative difference in flipper length between members of the pair. Females with larger flippers had a higher probability of raising two chicks. No effects of body measurements or degree of sexual dimorphism on body condition or T-cell-mediated immune response of offspring were found. We discuss these results in the context of potential factors responsible for the maintenance of sexual size dimorphism in this species.

scholarly journals Mate selection based on labile traits affects short-term fitness in a long-lived seabird

2020 ◽  
Vol 287 (1922) ◽  
pp. 20192578
Author(s):  
Erick González-Medina ◽  
José Alfredo Castillo-Guerrero ◽  
José A. Masero ◽  
Guillermo Fernández
Keyword(s):  
Assortative Mating ◽  
Body Condition ◽  
Mate Selection ◽  
Substantial Effect ◽  
Foraging Habitat ◽  
Short Term ◽  
Sula Nebouxii ◽  
Breeding Parameters ◽  
Social Species ◽  
Offspring Growth

In long-lived monogamous social species, partner compatibility can play a crucial role in reproductive success. We evaluated assortative mating based on body condition (plasma triglyceride concentration), diet (δ 15 N), and foraging habitat (δ 13 C) in the blue-footed booby Sula nebouxii , a long-lived monogamous seabird. We investigated the effects of assortative mating (sum of triglycerides in a pair) and asymmetry within pairs (residuals from regression of female–male triglycerides) on reproductive performance and offspring growth (alkaline phosphatase, ALP). We found that strong assortative mating determined by body condition and diet seemed to be related to a signalling mechanism (nutritional state). This mating pattern had a substantial effect on the breeding parameters and influenced offspring ALP. Within-pair asymmetry did not influence any reproductive parameters, but the ALP of offspring was related to the within-pair relative female condition. Overall, our results indicate that individuals seek the best possible match to maximize their breeding investment and/or individuals are limited in their mate options by their current body condition, which has consequences for offspring fitness in the short term. Our findings show that assortative mating based on body condition produces notable variation in the joint condition of the pair, which determines their breeding success.

scholarly journals Reproductive potential of a vole pest (Arvicola scherman) in Spanish apple orchards

2016 ◽  
Vol 14 (4) ◽  
pp. e1008 ◽  
Author(s):  
Aitor Somoano ◽  
Marcos Miñarro ◽  
Jacint Ventura
Keyword(s):  
Body Condition ◽  
Life Histories ◽  
Management Practices ◽  
Reproductive Potential ◽  
The Body ◽  
Crop Damage ◽  
First Year ◽  
Apple Orchards ◽  
Tree Roots ◽  
Second Year

Fossorial water voles, Arvicola scherman, feed on tree roots causing important damages in European apple orchards. Since the intensity of crop damage produced by rodents ultimately depends on their inherent capacity to increase their population, the main goal of this study was to determine the reproductive potential of the subspecies A. scherman cantabriae in apple orchards from Asturias (NW Spain), where voles breed over the whole year. Our results were compared with those reported for the subspecies A. scherman monticola from the Spanish Pyrenees (where reproduction ceases in winter). Sexual characteristics, body condition, relative age class and number of embryos were recorded from 422 females caught in apple orchards along two years. We found pregnant females all along the year, which were able to produce a high number of litters per year (7.30) although litter size was relatively moderate (first year: 3.87 embryos/female; second year: 3.63 embryos/females). The potential number of pups per female and year (first year: 28.25; second year: 26.50) was substantially higher than that reported for Pyrenean voles, what is probably related with differences in the length of the breeding season and in life histories between subspecies. In our population, the number of implanted embryos correlated positively with the body condition of the mother. Our results reveal that management efforts should not be seasonal as they used to be so far and invite to explore the physiological consequences of management practices.

scholarly journals Relation of Automated Body Condition Scoring System and Inline Biomarkers (Milk Yield, β-Hydroxybutyrate, Lactate Dehydrogenase and Progesterone in Milk) with Cow’s Pregnancy Success

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1414
Author(s):  
Ramūnas Antanaitis ◽  
Vida Juozaitienė ◽  
Dovilė Malašauskienė ◽  
Mindaugas Televičius ◽  
Mingaudas Urbutis ◽  
...  
Keyword(s):  
Lactate Dehydrogenase ◽  
Reproductive Success ◽  
Milk Yield ◽  
Body Condition ◽  
Body Condition Score ◽  
The Body ◽  
Time Analyzer ◽  
Condition Score ◽  
Pregnancy Status ◽  
Body Condition Scoring

The aim of the current study was to evaluate the relation of automatically determined body condition score (BCS) and inline biomarkers such as β-hydroxybutyrate (BHB), milk yield (MY), lactate dehydrogenase (LDH), and progesterone (mP4) with the pregnancy success of cows. The cows (n = 281) had 2.1 ± 0.1. lactations on average, were 151.6 ± 0.06 days postpartum, and were once tested with “Easy scan” ultrasound (IMV imaging, Scotland) at 30–35 d post-insemination. According to their reproductive status, cows were grouped into two groups: non-pregnant (n = 194 or 69.0% of cows) and pregnant (n = 87 or 31.0% of cows). Data concerning their BCS, mP4, MY, BHB, and LDH were collected each day from the day of insemination for 7 days. The BCS was collected with body condition score camera (DeLaval Inc., Tumba, Sweden); mP4, MY, BHB, and LDH were collected with the fully automated real-time analyzer Herd Navigator™ (Lattec I/S, Hillerød, Denmark) in combination with a DeLaval milking robot (DeLaval Inc., Tumba, Sweden). Of all the biomarkers, three differences between groups were significant. The body condition score (BCS) of the pregnant cows was higher (+0.49 score), the milk yield (MY) was lower (−4.36 kg), and milk progesterone in pregnant cows was (+6.11 ng/mL) higher compared to the group of non-pregnant cows (p < 0.001). The pregnancy status of the cows was associated with their BCS assessment (p < 0.001). We estimated that cows with BCS > 3.2 were 22 times more likely to have reproductive success than cows with BCS ≤ 3.2.

scholarly journals Ecological and Physiological Factors Affecting Brood Patch Area and Prolactin Levels in Arctic-Nesting Geese

The Auk ◽  
2006 ◽  
Vol 123 (2) ◽  
pp. 405-418 ◽  
Author(s):  
Jón Einar Jónsson ◽  
Alan D. Afton ◽  
Ray T. Alisauskas ◽  
Cynthia K. Bluhm ◽  
Mohamed E. El Halawani
Keyword(s):  
Body Condition ◽  
The Body ◽  
Nest Size ◽  
Patch Area ◽  
Physiological Factors ◽  
Factors Affecting ◽  
Chen Caerulescens ◽  
Brood Patch ◽  
Snow Geese ◽  
Ross's Geese

AbstractWe investigated effects of ecological and physiological factors on brood patch area and prolactin levels in free-ranging Lesser Snow Geese (Chen caerulescens caerulescens; hereafter “Snow Geese”) and Ross's Geese (C. rossii). On the basis of the body-size hypothesis, we predicted that the relationships between prolactin levels, brood patch area, and body condition would be stronger in Ross's Geese than in the larger Snow Geese. We found that brood patch area was positively related to clutch volume and inversely related to prolactin levels in Ross's Geese, but not in Snow Geese. Nest size, nest habitat, and first egg date did not affect brood patch area in either species. Prolactin levels increased as incubation progressed in female Snow Geese, but this relationship was not significant in Ross's Geese. Prolactin levels and body condition (as indexed by size-adjusted body mass) were inversely related in Ross's Geese, but not in Snow Geese. Our findings are consistent with the prediction that relationships between prolactin levels, brood patch area, and body condition are relatively stronger in Ross's Geese, because they mobilize endogenous reserves at faster rates than Snow Geese.Factores Ecológicos y Fisiológicos que Afectan el Área del Parche de Incubación y los Niveles de Prolactina en Gansos Nidificantes del Ártico

Implications of body condition and seasonality on morphological and functional parameters of testes of Myotis nigricans (Chiroptera: Vespertilionidae)

2018 ◽  
Vol 30 (7) ◽  
pp. 1029
Author(s):  
Marcelo Ferreira ◽  
Aline Soldati ◽  
Sirlene S. S. Rodrigues ◽  
Laércio dos Anjos Benjamin
Keyword(s):  
Light Microscopy ◽  
Body Condition ◽  
Environmental Variables ◽  
Reproductive Strategies ◽  
Leydig Cells ◽  
Dry Season ◽  
The Body ◽  
Reproductive Capacity ◽  
Seminiferous Tubules ◽  
The Mean

The insectivorous bat Myotis nigricans is widely distributed throughout the Neotropics, including Brazil, and has a reproductive biology that is affected by climate and food availability. To evaluate the reproductive capacity of this species, morphofunctional parameters of the testes were correlated with environmental variables and the body condition of individuals captured. After bats had been killed, their testes were removed, fixed in Karnovsky’s fluid for 24 h and embedded in resin for evaluation by light microscopy. The mean annual tubulosomatic index (0.58%) and the percentage of seminiferous tubules in the testes (88.96%) were the highest ever recorded for the Order Chiroptera. The percentage of Leydig cells and volume of the cytoplasm of Leydig cells were higher in the rainy than dry season (80.62 ± 3.19% and 573.57 ± 166.95 μm, respectively; mean ± s.d.). Conversely, the percentage of nuclei of the Leydig cells in the dry season (26.17 ± 3.70%; mean ± s.d.) and the total number of Leydig cells (6.38 ± 1.84 × 109; mean ± s.d.) were higher in the dry season. The results of the present study could help in future conservation of these bats because they provide a better understanding of the bats’ reproductive strategies and how the species can adapt to changes.

scholarly journals Decline in body condition in the Antarctic minke whale (Balaenoptera bonaerensis) in the Southern Ocean during the 1990s

Polar Biology ◽  
2021 ◽  
Vol 44 (2) ◽  
pp. 259-273
Author(s):  
Céline Cunen ◽  
Lars Walløe ◽  
Kenji Konishi ◽  
Nils Lid Hjort
Keyword(s):  
Model Selection ◽  
Body Condition ◽  
Model Building ◽  
Research Question ◽  
Information Criterion ◽  
The Body ◽  
Antarctic Minke Whale ◽  
Minke Whales ◽  
Balaenoptera Bonaerensis ◽  
The Antarctic

AbstractChanges in the body condition of Antarctic minke whales (Balaenoptera bonaerensis) have been investigated in a number of studies, but remain contested. Here we provide a new analysis of body condition measurements, with particularly careful attention to the statistical model building and to model selection issues. We analyse body condition data for a large number (4704) of minke whales caught between 1987 and 2005. The data consist of five different variables related to body condition (fat weight, blubber thickness and girth) and a number of temporal, spatial and biological covariates. The body condition variables are analysed using linear mixed-effects models, for which we provide sound biological motivation. Further, we conduct model selection with the focused information criterion (FIC), reflecting the fact that we have a clearly specified research question, which leads us to a clear focus parameter of particular interest. We find that there has been a substantial decline in body condition over the study period (the net declines are estimated to 10% for fat weight, 7% for blubber thickness and 3% for the girth). Interestingly, there seems to be some differences in body condition trends between males and females and in different regions of the Antarctic. The decline in body condition could indicate major changes in the Antarctic ecosystem, in particular, increased competition from some larger krill-eating whale species.

Ntrauterine programming of women’s health as a determinant of the reproductive potential of a population

2017 ◽  
pp. 10-15
Author(s):  
L.G. Nazarenko ◽  
◽  
N.S. Nestertsova ◽  
Keyword(s):  
World Literature ◽  
System Development ◽  
Reproductive Potential ◽  
The Body ◽  
Large For Gestational Age ◽  
Relevant Research ◽  
Gynecological Diseases ◽  
The World ◽  
Oncological Diseases ◽  
The Relationship

The relationship between the body weight of women at birth and the development in the future of gynecological diseases or deviations in the development of the reproductive system, development of oncological diseases and the timing of menopause have been analyzed. The results of clinical studies conducted at different times in different countries of the world, which cover the topic of this article, are presented. An overview of the world literature presented in the article, substantiates the relevance of conducting relevant research in the Ukrainian population. Key words: low birth weight, large-for-gestational-age fetus, gynecology disease.

scholarly journals Reproductive strategies of two Curimatidae species in a Mogi Guaçu impoundment, upper Paraná River basin, São Paulo, Brazil

2012 ◽  
Vol 10 (4) ◽  
pp. 847-854 ◽  
Author(s):  
Alexandre Peressin ◽  
Cristina da Silva Gonçalves ◽  
Francisco Manoel de Souza Braga
Keyword(s):  
Body Condition ◽  
Reproductive Strategies ◽  
Feeding Activity ◽  
Reproductive Period ◽  
The Body ◽  
Management Plans ◽  
Dry Seasons ◽  
Upper Paraná River ◽  
Upper Paraná River Basin ◽  
Wet And Dry Seasons

Considering that reproduction studies are fundamental to understand the life cycle of organisms, this study aimed to investigate the reproductive strategies of saguirus Cyphocharax nagelii and Steindachnerina insculpta in a dam of Mogi Guaçu River, (SP). Specimens were collected between August 2005 and July 2006 using gillnets with mesh sizes ranging from 1.5 to 5.0 cm between adjacent knots. Reproductive dynamics, body condition, reproductive period, spawning type and fecundity were analyzed in both species. The body condition reflected the reproductive dynamics, and differed significantly between the wet and dry seasons. During the dry season, the feeding activity and the accumulation of fat in the visceral cavity were higher. The reproductive period of both species covered the months between August and February, with peaks in October and December, and the distribution of the diameters of oocytes allowed to classify them as total spawners. The fecundity increased with weight and length, reaching 28,800 and 27,906 oocytes per female for C. nagelii and S. insculpta, respectively, whereas the amplitude of oocyte diameters varied between 50-1025 µm for the former and 75-975 µm for the later species. Taking into account that species with different reproductive strategies also respond differently to environmental impacts, our findings provide important information to subsidize management plans for these curimatid species.

Sign in / Sign up

Export Citation Format

Share Document