State-dependent decisions in long-term fasting king penguins, Aptenodytes patagonicus, during courtship and incubation
Using an automatic identification and weighing system, we investigated changes in adult body mass in relation to reproductive behaviour during courtship and incubation in free-living king penguins. Despite stressful nutritional conditions and variability of fast length, the majority of pairs incubated successfully by accumulating large body reserves before fasting, which provided flexibility in fasting strategies. […]
Assessment of body condition in Asian elephants (Elephas maximus)
Abstract 10.1002/zoo.20099.abs A method of assessing body condition of Asian elephants (Elephas maximus) is presented. The method uses visual assessment to assign numerical scores to six different regions of the body, which are totaled to give a numerical index ranging from 0–11. The relationship between the index and morphometric variables is compared for a sample […]
Behavior of giant pandas (Ailuropoda melanoleuca) in captive conditions: Gender differences and enclosure effects
Abstract 10.1002/zoo.10076.abs The behavior of giant pandas (Ailuropoda melanoleuca) was studied under captive conditions. Both male and female pandas spent similar amounts of time engaged in eating and locomotion. Males performed anogenital-marking more but rested less than females, which suggests a sexually dimorphic pattern of behavior. Furthermore, females housed in the seminatural environment spent significantly […]
Food consumption and growth of California sea lions (Zalophus californianus californianus)
Abstract 10.1002/1098-2361(2000)19:23.3.CO;2-F The daily food consumption of 26 California sea lions at the Harderwijk Marine Mammal Park was recorded. Average annual food consumption of males increased with age to stabilize at approximately 4,000 kg/year by the age of 10 years. Females showed a rapid increase in average annual food consumption until they were 3 years […]
Determinants of vertebrate invasion success in Europe and North America
Species that are frequently introduced to an exotic range have a high potential of becoming invasive. Besides propagule pressure, however, no other generally strong determinant of invasion success is known. Although evidence has accumulated that human affiliates (domesticates, pets, human commensals) also have high invasion success, existing studies do not distinguish whether this success can […]
Studies on UV reflection in feathers of some 1000 bird species: are UV peaks in feathers correlated with violet-sensitive and ultraviolet-sensitive cones?
Nine hundred and sixty-eight bird species, covering all orders, were studied in search of distinctive ultraviolet reflections. All species in the following orders were completely surveyed: Struthioniformes, Tinamiformes, Craciformes, Turniciformes, Galbuliformes, Upupiformes, Coliiformes, Apodiformes and Musophagiformes. The coloured plumage regions in particular exhibited high proportions of UV-reflecting feathers. Bird orders with species which are believed […]
Functional significance of a phylogenetically widespread sexual dimorphism in vasotocin/vasopressin production
Male-biased production of arginine vasotocin/vasopressin (VT/VP) in the medial bed nucleus of the stria terminalis (BSTm) represents one of the largest and most phylogenetically widespread sexual dimorphisms in the vertebrate brain. Although this sex difference was identified 30 years ago, the function of the dimorphism has yet to be determined. Because 1) rapid transcriptional activation […]