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Adult Diet (adult + diet)
Selected AbstractsVariation in the use of pasture by breeding European Golden Plovers Pluvialis apricaria in relation to prey availabilityIBIS, Issue 3 2003J. W. Pearce-Higgins European Golden Plover Pluvialis apricaria populations have declined across Western Europe. Changes to upland grasslands that are utilized by foraging off-duty birds may have contributed to this decline. The use of enclosed agricultural land by a stable breeding population of Golden Plovers in the South Pennines is described to examine this hypothesis. Fields contained foraging plovers from the end of February to the end of July. Off-duty incubating birds commuted to feed on fields, females during the day and males at night. During the day, adults flew from 6.6 to 7.2 km from the nest to feed, whilst at night birds commuted from 2.4 to 2.7 km. The length of time spent foraging by males was inversely dependent upon daylength. Following hatching, the use of pasture declined, although not as much as in other studies. Arable and improved fields received most use by 15 radiotagged birds, whilst the use of pasture throughout the breeding season was negatively correlated with sward height. Adult diet consisted largely of subsurface prey, particularly larval tipulids, although earthworms were an important component in March and April. The biomass of larval tipulids was strongly correlated with an index of the use of fields. The selection of fields by Golden Plovers is therefore dependent upon prey abundance and availability, and, consequently, is likely to be enhanced by summer grazing and poor drainage. These findings are discussed in the light of recent trends in pastoral management. [source] Amino acid sources in the adult diet do not affect life span and fecundity in the fruit-feeding butterfly Bicyclus anynanaECOLOGICAL ENTOMOLOGY, Issue 4 2008FREERK MOLLEMAN Abstract 1.,In tropical forests, the adults of many butterfly species feed on fruits rather than nectar from flowers and have long life spans. Rotting fruit and nectar differ from each other in many respects, including sources of amino acids and microbial life. If amino acids in the adult diet can be used for reproduction, this may have facilitated the evolution of extended life spans in this guild. 2.,This issue was addressed by investigating effects of banana, yeast, and amino acids in the adult diet of the fruit-feeding butterfly Bicyclus anynana (Lepidoptera) on longevity and female reproductive output in two experiments. 3.,Results showed that in the fruit-feeding butterfly B. anynana: (i) banana juice, but not sliced banana or added amino acids extend life span compared with a sugar solution of similar composition; (ii) compared with this sugar solution, other cohorts (banana juice-amino acid enriched) did not have significantly higher reproductive outputs; (iii) yeast does not represent a valuable source of nutrients; (iv) caloric restriction may cause decreased life span and rate of reproduction; and (v) increased rates of reproduction have a life span cost. [source] Life-history strategy in an oligophagous tephritid: the tomato fruit fly, Neoceratitis cyanescensECOLOGICAL ENTOMOLOGY, Issue 4 2008THIERRY BRÉVAULT Abstract 1.,In phytophagous insects, life-history traits mainly depend on host plant range. Substantial longevity, high fecundity and larval competition are the major traits of polyphagous Tephritidae while species with a restricted host range generally exhibit a lower longevity and fecundity as well as mechanisms to avoid larval competition. Our aim in this study was to investigate the life history of an oligophagous species, the tomato fruit fly, Neoceratitis cyanescens (Bezzi). 2.,We determined life tables under laboratory conditions in order to calculate the main demographic parameters of N. cyanescens and studied the influence of larval and adult diet on life-history traits. 3.,The mean longevity of N. cyanescens females was 40 days. There was a strong synchronisation of female maturity. Oviposition showed an early peak at 9,13 days after a short pre-oviposition period (6 days). The absence of proteins in the adult diet both delayed ovarian maturation and decreased female fecundity. In addition, females originating from tomato fruits produced significantly more eggs than females originating from bugweed or black nightshade, showing that even the larval host plant may strongly affect the subsequent fecundity of adult females. 4.,The traits of N. cyanescens are then discussed in the light of those documented for polyphagous and monophagous tephritids. Neoceratitis cyanescens displayed attributes intermediate between those of polyphagous and monophagous tephritids. Its smaller clutch size compared with polyphagous species and its specialisation on the Solanaceae family whose fruits contain toxic compounds may help in reducing intra- and inter-specific competition, respectively. [source] Burying beetle Nicrophorus investigator reproduction on Pacific salmon carcassesECOLOGICAL ENTOMOLOGY, Issue 1 2006M. D. Hocking Abstract., 1.,In many undisturbed watersheds along the Pacific Rim, anadromous salmon (Oncorhynchus spp.) provide a predictable source of carrion to the riparian zone, largely due to horizontal transfer of salmon carcasses by bears (Ursus spp.) and other vertebrates. 2.,Burying beetles are important members of the north-temperate carrion fauna, and may utilise salmon carcasses and remnants for breeding. In this study, isotopic and observational data are reported that demonstrate previously unrecognised Nicrophorus investigator (Zetterstedt) reproduction on large salmon carcasses from five watersheds in coastal British Columbia. 3.,Stable isotope signatures (,15N and ,13C) of adult beetles collected in autumn indicate a diet of salmon origin in all but one individual from all watersheds, suggesting that this beetle,salmon association is widespread. Comparison of autumn isotope signatures to individuals collected randomly in summer suggests that isotope signatures represent the larval carrion source from the previous autumn rather than immediate adult diet. 4.,In a survey of N. investigator use of salmon carcasses from two watersheds, 35 broods were observed on chum and pink salmon carcasses, including 16 natural brood complexes containing over 100 larvae, and five ranging from 250 to 750 larvae. 5.,Overall, north-coastal populations of N. investigator breed on the rich and reliable salmon resource and may exhibit a system of communal breeding on these carcasses. This is most relevant when the dramatic reduction in salmon spawning biomass over the last century is considered. [source] Relationship between diet composition and the fecundity of Musca domesticaENTOMOLOGICAL RESEARCH, Issue 6 2009Ran WON Abstract A study of the relationship between diet compositions of housefly Musca domestica and the fecundity of the insect was carried out. Fecundity was increased more than 30% by adding a protein source and inorganic salts into the larval and adult diets. Also, adding a protein source into the adult diet prolonged the oviposition period of adult houseflies. [source] Diet and Its Relationship with Grip Strength in Community-Dwelling Older Men and Women: The Hertfordshire Cohort StudyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 1 2008Sian M. Robinson PhD OBJECTIVES: To examine relationships between diet and grip strength in older men and women and to determine whether prenatal growth modifies these relationships. DESIGN: Cross-sectional and retrospective cohort study. SETTING: Hertfordshire, United Kingdom. PARTICIPANTS: Two thousand nine hundred eighty-three men and women aged 59 to 73 who were born and still living in Hertfordshire, United Kingdom. MEASUREMENTS: Weight at birth recorded in Health Visitor ledgers; current food and nutrient intake assessed using an administered food frequency questionnaire; and grip strength measured using a handheld dynamometer. RESULTS: Grip strength was positively associated with height and weight at birth and inversely related to age (all P<.001). Of the dietary factors considered in relation to grip strength, the most important was fatty fish consumption. An increase in grip strength of 0.43 kg (95% confidence interval (CI)=0.13,0.74) in men (P=.005) and 0.48 kg (95% CI=0.24,0.72) in women (P<.001) was observed for each additional portion of fatty fish consumed per week. These relationships were independent of adult height, age, and birth weight, each of which had additive effects on grip strength. There was no evidence of interactive effects of weight at birth and adult diet on grip strength. CONCLUSION: These data suggest that fatty fish consumption can have an important influence on muscle function in older men and women. This raises the possibility that the antiinflammatory actions of omega-3 fatty acids may play a role in the prevention of sarcopenia. [source] Begging for information: mother,offspring food sharing among wild Bornean orangutansAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2008Adrian V. Jaeggi Abstract Transfer of solid food from mothers or other adults to dependent offspring is commonly observed in various primate species and both nutritional and informational benefits have been proposed to explain the function of such food sharing. Predictions from these hypotheses are tested using observational data on wild orangutans (Pongo pygmaeus wurmbii) at Tuanan, Central Borneo, Indonesia. In 1,145,hr of focal observation and 458 recorded food interactions between four pairs of females with offspring it was found that virtually all transfers were initiated by the offspring and that younger infants solicited food more often and did so for a greater variety of items than older offspring. All offspring primarily solicited food that was difficult to process, i.e., inaccessible to them. Furthermore, the amount of food solicitation was negatively correlated with ecological competence. Hence food sharing seemed to be related to an offspring's skill level, as suggested by the informational hypothesis. In contrast, offspring did not solicit high-quality items more than low-quality items and food sharing did not peak around the age of weaning, as predicted by the nutritional hypothesis. Mothers were usually passively tolerant, allowing offspring to take food but hardly ever provisioned. Parent,offspring conflict concerning food sharing was only observed well after weaning. Thus, by taking food directly from the mother, young orangutans were able to obtain information about the affordances and nutritional value of food items that were otherwise out of their reach and could familiarize themselves with the mother's diet. In species such as orangutans or other apes, characterized by a broad diet that requires extractive foraging, informational food transfer may be vital for an immature to acquire complex feeding skills and adult diet. Am. J. Primatol. 70:533,541, 2008. © 2008 Wiley-Liss, Inc. [source] Relationship between diet composition and the fecundity of Musca domesticaENTOMOLOGICAL RESEARCH, Issue 6 2009Ran WON Abstract A study of the relationship between diet compositions of housefly Musca domestica and the fecundity of the insect was carried out. Fecundity was increased more than 30% by adding a protein source and inorganic salts into the larval and adult diets. Also, adding a protein source into the adult diet prolonged the oviposition period of adult houseflies. [source] Sex differences in grey seal diet reflect seasonal variation in foraging behaviour and reproductive expenditure: evidence from quantitative fatty acid signature analysisJOURNAL OF ANIMAL ECOLOGY, Issue 3 2007CARRIE A. BECK Summary 1Intraspecific variation in diet can be an important component of a species niche breadth. We tested the hypothesis that sex differences in seasonal foraging behaviour and energy storage of sexually size dimorphic grey seals Halichoerus grypus (Fabrisius 1971) are reflected in differences in the diet and niche breadth. Diet composition was estimated for 496 adult (226 males, 270 females) and 91 juvenile (46 males/45 females; all 6 months old) grey seals sampled between 1993 and 2000 using quantitative fatty acid signature analysis. Niche breadth and overlap were estimated using the Shannon,Weaver diversity index (H,) and the Morisita,Horn index (CH), respectively. 2Sand lance Ammodytes dubius (Reinhardt 1837) and redfish Sebastes sp. (Cuvier 1829) accounted for a high proportion of the diet in both sexes and age groups. However, the diets of adult males were significantly more diverse across all seasons (H,: males 0·36 ± 0·007 vs. females 0·28 ± 0·007) and less energy dense in spring (male 5·3 ± 0·07 kJ g,1 vs. females 5·6 ± 0·09 kJ g,1) than those of adult females. 3Season and sex explained most of the observed variation in adult diets, but there were significant sex,season interactions. These differences were most evident during the post-breeding (spring) foraging period when energy acquisition is important to female recovery of nutrient stores needed to support pregnancy. Females selected fewer and higher quality prey species in spring than males. 4There were no sex differences in the diets of juvenile grey seals. Although many of the species overlapped with those eaten by adults, juvenile niche breadth (H,: 0·41 ± 0·014, n = 91) was significantly broader than that of adults (H,: 0·30 ± 0·011, n = 115). Juvenile diets were also of lower energy density (5·3 ± 0·04 kJ g,1) than those of adults (5·6 ± 0·09 kJ g,1), suggesting less selectivity in these young and relatively naïve predators. 5Sex-specific seasonal changes in diet correspond to seasonal changes in diving behaviour and rate of body energy accumulation of adult males and females. Sex-specific reproductive requirements appear to be a primary factor generating the intraspecific variation in the seasonal foraging ecology of this large marine carnivore. However, sex differences in the breadth and energy content of diets also suggest the influence of body-size dimorphism as a factor shaping the diet of this species. [source] DIET OF HARBOR PORPOISES IN THE KATTEGAT AND SKAGERRAK SEAS: ACCOUNTING FOR INDIVIDUAL VARIATION AND SAMPLE SIZEMARINE MAMMAL SCIENCE, Issue 1 2003Patrik Börjesson Abstract Stomach contents of 112 bycaught harbor porpoises (Phocoena phocoena) collected between 1989 and 1996 in the Kattegat and Skagerrak seas were analyzed to describe diet composition and estimate prey size, to examine sample size requirements, and to compare juvenile and adult diets. Although porpoises preyed on a variety of species, only a few contributed substantially to the diet. Atlantic herring (Clupea harengus) was the dominating prey species for both juveniles and adults. Our results, in combination with those from previous studies, suggest that where herring is a dominant food source, porpoises prey primarily on size classes containing mature or maturing individuals. Further, we also show that Atlantic hagfish (Myxine glutinosa) may be an important food resource, at least for adult porpoises. Examination of sample size requirement showed that, depending on the taxonomic level used to describe the diet, a minimum of 35,71 stomachs are needed to be confident that all common prey species will be found. [source] | ||||||||||