It is proposed that where sexually selected vocal communication is an honest signal, the call production rate is predicted to change throughout the breeding season. Male leopard seals call underwater for many hours each day over their three- to four-month breeding season, and it is hypothesized that a decrease in calling rate would be associated with the declining body condition of smaller male...

Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. ...

A total of 1474 and 1935 production and reproduction records of crossbred cattle and Murrah buffaloes from the year 1992 to 2012 were utilized in the present study to investigate breeding efficiency (BE) and various performance traits. Breeding efficiency was calculated using Wilcox and Tomar methods and Least –squares of Harvey model was used to study the effects of various non-genetic factors...

Timing of reproduction in a seasonal cycle is a life history trait with important fitness consequences. Capital breeders produce offspring from stored resources and, by decoupling feeding and reproduction, may bend the constraints caused by seasonality in food or predation. Income breeders, on the other hand, produce offspring from concurrent food intake, with the disadvantage of less flexibili...

Knowledge of the basic reproductive physiology of snow leopards is required urgently in order to develop a suitable management conditions under captivity. In this study, the long-term monitoring of concentrations of three steroid hormones in fecal matter of three female snow leopards was performed using enzyme immunoassays: (1) estradiol-17β, (2) progesterone and (3) cortisol metabolite. Two of...

This study reports the gender and seasonal specificity of hormonal, behavioral, and coloration responses displayed by "resident" male lizards (Sceloporus undulatus) exposed to male or female "intruders" during staged encounters in outdoor enclosures. Resident males were engaged in staged encounters with males or females for 1 h per day on 9 consecutive days during the breeding and postbreeding ...

In birds, parents adjust their feeding behaviour according to breeding duties, which ultimately may lead to seasonal adjustments in nutritional physiology and hematology over the breeding season. Although avian physiology has been widely investigated in captivity, few studies have integrated individual changes in feeding and physiological ecology throughout the breeding season in wild birds. To...

The house mouse has adapted well to the cereal crops of south-eastern Australia where populations show aperiodic outbreaks over large areas. A 20-year population study has provided a wealth of information on breeding ecology, demographic changes, spatial behaviour and epidemiology. The breeding season can be as short as 4.5 months and as long as 10 months with litter size changing seasonally fr...

In order to attribute the behaviour of an animal to its personality it is important to study whether certain behavioural traits show up consistently across a variety of contexts. The aim of this study was to investigate whether breeding state males of the two-spotted goby, Gobiusculus flavescens, showed consistent degree of boldness when tested in four different behaviour assays. We also wanted...

The habitat suitability index, which reflects spatial variability in species occurrence probability, has been shown to exhibit various contrasting relationships with local demographic performances (survival, productivity) in several species. One proposed explanation for these discrepancies is that the link between the habitat suitability index and demography is influenced by density-dependent, ...