Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
ornithodoros (alectorobius) amblus (acarina: ixodoidea: argasidae): identity, marine bird and human hosts, virus infections, and distribution in peru.ornithodoros (alectorobius) amblus chamberlin 1920, adults previously were described inadequately. practically nothing was known regarding the identity, hosts, distribution, and biology of this species. we redescribe both sexes, describe the nymph and larva, and present criteria for differentiating these stages from those of other members of the o. (a.) capensis group in the western hemisphere. samples were collected from 13 localities on the pacific coast and on offshore islands of peru. hosts ...19807391872
proximate and ultimate roles of food amount in regulating egret sibling aggression.in facultatively siblicidal bird species, the amount of food delivered by parent birds to their young ("food amount") has been assumed to be both an important proximate and ultimate cause of fatal aggression. the proximate "food amount hypothesis" (fah) contends that sibling aggression will vary inversely with the quantity of food delivered by the parents, presumably mediated by chick hunger. at the ultimate level, food shortages are expected to influence whether the combined effects of aggressi ...198729357167
dominance between booby nestlings involves winner and loser effects.two-chick broods of the blue-footed booby, sula nebouxii, ordinarily exhibit stable dominance-subordinance, with the senior (first-hatched) chick habitually aggressive and the junior one habitually submissive (nelson 1978, the sulidae: gannets and boobies. london: oxford university press). but are both the subordinate and the dominant chick affected in their agonistic tendencies by early social experience? to answer this, we permanently paired subordinate and dominant chicks, 2-3 weeks old, with ...19989642010
the effects of an "el niño" southern oscillation event on reproduction in male and female blue-footed boobies, sula nebouxii.this study attempted to determine endocrine correlates of reproductive success in relation to major deleterious environmental conditions. in 1992, an el niño southern oscillation event resulted in complete reproductive failure in a colony of blue-footed boobies, sula nebouxi, on isla isabel in the pacific ocean off san blas, nayarit, mexico (21.5 degrees n, 105.5 degrees w). in 1993, the el niño event had waned and reproductive success was high. the mean sea surface temperature in 1992 was 26.69 ...199910208765
variably male-biased sex ratio in a marine bird with females larger than males.when the costs of rearing males and females differ progeny sex ratios are expected to be biased toward the less expensive sex. blue-footed booby (sula nebouxii) females are larger and roughly 32% heavier than males, thus presumably more costly to rear. we recorded hatching and fledging sex ratios in 1989, and fledging sex ratios during the next 5 years. in 1989, the sample of 751 chicks showed male bias at hatching (56%) and at fledging (57% at 90 days). fledging sex ratios during the five subse ...199920135156
nesting distributions of galápagos boobies (aves: sulidae): an apparent case of amensalism.blue-footed boobies (sula nebouxii) in the galápagos islands nest at coastal sites such as cliff edges if nazca boobies (s. granti) are absent. however, if sympatric with nesting nazca boobies, they nest nearby, but farther inland, in areas with little topographical relief. nazca boobies nest at the coastal sites whether blue-footed boobies are present or not. the segregated nesting pattern of these two species offers a model system to investigate factors influencing community structure. we test ...200228547420
buffered development: resilience after aggressive subordination in infancy.do aggressive dominance and subordination in vertebrate broods and litters affect development? we examined 1,167 fledglings from two-chick broods of the blue-footed booby (sula nebouxii), a species in which the first-hatched chick dominates with violent attacks throughout the nestling period and subordinates suffer lower fledging success, but if both broodmates survive, they grow to the same size. there was little evidence that dominant fledglings were more likely to recruit into the breeding po ...200312858285
pigment-based skin colour in the blue-footed booby: an honest signal of current condition used by females to adjust reproductive investment.in monogamous species, the value of present reproduction is affected by the current condition of the mate, and females may use male ornaments to evaluate his condition and adjust their level of investment according. many animals display colour in fleshy structures which may be accurate indicators of quality due to their potentially rapid response to changes in condition. here we show that in the blue-footed booby, sula nebouxii, male foot colour is structurally (collagen arrays) and pigment base ...200616821015
senescent birds redouble reproductive effort when ill: confirmation of the terminal investment hypothesis.this study reports an experimental confirmation of the terminal investment hypothesis, a longstanding theoretical idea that animals should increase their reproductive effort as they age and their prospects for survival and reproduction decline. previous correlational and experimental attempts to test this hypothesis have yielded contradictory results. in the blue-footed booby, sula nebouxii, a long-lived bird, after initial increase, male reproductive success declines progressively with age. bef ...200616777735
does extra corticosterone elicit increased begging and submissiveness in subordinate booby (sula nebouxii) chicks?we tested whether in two-chick broods of the blue-footed booby (sula nebouxii) elevated circulating corticosterone in the socially subordinate broodmate facilitates submissive behavior and/or enhances food solicitation. implanting corticosterone in 17 subordinate chicks (experimental broods) produced changes in the behavior of chicks and parents over the first two days, relative to 17 matched families (control broods) where subordinate chicks were implanted with empty capsules. experimental broo ...200616530762
male reproductive senescence: the price of immune-induced oxidative damage on sexual attractiveness in the blue-footed booby.in animals, male reproduction is commonly a function of sexual attractiveness, based on the expression of sexually dimorphic traits that advertise genuinely the male's quality. male performance may decline with age because physiological functions underlying sexual attractiveness may be affected by senescence. here we show that a sexual signal (foot colour) declines with age, due probably to the deleterious effects of oxidative damage. we found that in the blue-footed booby sula nebouxii foot col ...200717922712
effects of breeding success, mate fidelity and senescence on breeding dispersal of male and female blue-footed boobies.1. understanding the effects of individual and population factors on variation in breeding dispersal (the movement of individuals between successive breeding sites) is key to identifying the strategies behind breeders' movements. dispersal is often influenced by multiple factors and these can be confounded with each other. we used 13 years of data on the locations, mates, breeding success and ages of individuals to tease apart the factors influencing breeding dispersal in a colonially breeding l ...200717439464
perinatal androgens and adult behavior vary with nestling social system in siblicidal boobies.exposure to androgens early in development, while activating adaptive aggressive behavior, may also exert long-lasting effects on non-target components of phenotype. here we compare these organizational effects of perinatal androgens in closely related nazca (sula granti) and blue-footed (s. nebouxii) boobies that differ in neonatal social system. the older of two nazca booby hatchlings unconditionally attacks and ejects the younger from the nest within days of hatching, while blue-footed booby ...200818560542
simultaneous positive and negative density-dependent dispersal in a colonial bird species.contradictory patterns of density-dependent animal dispersal can potentially be reconciled by integrating the conspecific attraction hypothesis with the traditional competition hypothesis. we propose a hypothesis that predicts a u-shaped relationship between density and both natal and breeding dispersal distance. using 10 years of observations on a breeding colony of the blue-footed booby (sula nebouxii), the hypothesis was confirmed by documenting simultaneous positive and negative density-depe ...200919294928
permanent genetic resources added to molecular ecology resources database 1 october 2009-30 november 2009.this article documents the addition of 411 microsatellite marker loci and 15 pairs of single nucleotide polymorphism (snp) sequencing primers to the molecular ecology resources database. loci were developed for the following species: acanthopagrus schlegeli, anopheles lesteri, aspergillus clavatus, aspergillus flavus, aspergillus fumigatus, aspergillus oryzae, aspergillus terreus, branchiostoma japonicum, branchiostoma belcheri, colias behrii, coryphopterus personatus, cynogolssus semilaevis, cy ...201021565039
parental conflict and blue egg coloration in a seabird.when both parents provide offspring care, equal sharing of costly parental duties may enhance reproductive success. this is crucial for longlived species, where increased parental effort in current reproduction profoundly affects future reproduction. indication of reproductive value or willingness to invest in reproduction may promote matching responses by mates, thus reducing the conflict over care. in birds with biparental care, blue-green eggshell color may function as a signal of reproductiv ...201020128107
senescence of maternal effects: aging influences egg quality and rearing capacities of a long-lived bird.senescence could depress prenatal and postnatal capacities of mothers to invest in offspring. longitudinal observations on the blue-footed booby (sula nebouxii) revealed a quadratic effect of female age on fledgling production and cohort differences in rate of reproductive decline. by swapping clutches between females of different ages, we tested whether reproductive senescence is due to decline in egg quality or capacity to care. as laying mothers aged, egg size, ulna length of 5-day-old chicks ...201020175680
climatic influence on demographic parameters of a tropical seabird varies with age and sex.in marine ecosystems climatic fluctuation and other physical variables greatly influence population dynamics, but differential effects of physical variables on the demographic parameters of the two sexes and different age classes are largely unexplored. we analyzed the effects of climate on the survival and recruitment of both sexes and several age classes of a long-lived tropical seabird, the blue-footed booby (sula nebouxii), using long-term observations on marked individuals. results demonstr ...201020462134
evolvability of an avian life history trait declines with father's age.studies of laboratory organisms have suggested that parental age affects the genetic variance of offspring traits. this effect can engender age-specific variance in genetic contributions to evolutionary change in heritable traits under directional selection, particularly in age-structured populations. using long-term population data of the blue-footed booby (sula nebouxii), we tested whether genetic variance of recruiting age varies with parental age. using robust quantitative genetic models fit ...201121044208
effects of recruiting age on senescence, lifespan and lifetime reproductive success in a long-lived seabird.theories of ageing predict that early reproduction should be associated with accelerated reproductive senescence and reduced longevity. here, the influence of age of first reproduction on reproductive senescence and lifespan, and consequences for lifetime reproductive success (lrs), were examined using longitudinal reproductive records of male and female blue-footed boobies (sula nebouxii) from two cohorts (1989 and 1991). the two sexes showed different relationships between age of first reprodu ...201121286924
senescent males carry premutagenic lesions in sperm.as organisms age, dna of somatic cells deteriorates, but it is believed that germ cells are protected from dna-damaging agents. in recent years, this vision has been challenged by studies on humans indicating that genomic instability in germ cells increases with age. however, nothing is known about germ line senescence in wild animals. here, we examine dna damage in sperm of a wild vertebrate, the blue-footed booby sula nebouxii. one of the major types of premutagenic dna damage generated by oxi ...201121332857
el niño in the warm tropics: local sea temperature predicts breeding parameters and growth of blue-footed boobies.1. there is increasing interest in the impacts of el niño southern oscillation (enso) on reproduction of apical predators such as seabirds and marine mammals. long-term studies documenting enso effects on reproduction of seabirds in the warm tropics are scarce, and differential sensitivity of breeding parameters to enso has rarely been explored. 2. analysis of 18 years of breeding data from a colony of the blue-footed booby sula nebouxii (milne-edwards) showed a delay in onset of breeding when t ...201121366563
natural 'poor start' does not increase mortality over the lifetime.poor nutrition and other challenges during infancy can impose delayed costs, and it has been proposed that expression of costs during adulthood should involve increased mortality rather than reduced reproduction. demonstrations of delayed costs come mostly from experimental manipulations of the diet and hormones of captive infants of short-lived species, and we know very little about how natural poor starts in life affect wild animals over their lifetimes. in the blue-footed booby, sibling confl ...201121450729
sibling bullying during infancy does not make wimpy adults.despite frequent suggestions that dominance-subordination relationships in infancy can affect subsequent agonistic potential during adult life, to our knowledge no explicit test has been made. experiments have shown that adverse conditions during early development can have long-term effects on a variety of traits ranging from growth to competitive behaviour. in many vertebrate species, the main social setting in which the infant develops is a sibling group where competition is often mediated by ...201121697164
parental age and lifespan influence offspring recruitment: a long-term study in a seabird.recent studies of wild populations provide compelling evidence that survival and reproduction decrease with age because of senescence, a decline in functional capacities at old ages. however, in the wild, little is known about effects of parental senescence on offspring quality. we used data from a 21-year study to examine the role of parental age on offspring probability of recruitment in a long-lived bird, the blue-footed booby (sula nebouxii). offspring probability of recruiting into the bree ...201122087271
helminth parasites of the blue-footed booby on isla isabel, méxico.a survey of the helminth fauna of the blue-footed booby, sula nebouxii, on isla isabel, off the pacific coast of méxico, is presented. eight parasite species were found: 4 digeneans (galactosomum puffini , mesostephanus microbursa, opisthometra planicollis, and renicola thapari), 3 nematodes (contracaecum sp., porrocaecum sp., and tetrameres sp.), and 1 cestode (tetrabothrius sp). all these species are reported for the first time in the blue-footed booby, and they represent 8 new locality record ...201121506815
costs of growing up as a subordinate sibling are passed to the next generation in blue-footed boobies.as stresses in early development may generate costs in adult life, sibling competition and conflict in infancy are expected to diminish the reproductive value of surviving low-status members of broods and litters. we analysed delayed costs to blue-footed booby fledglings, sula nebouxii, of junior status in the brood, which involves aggressive subordination, food deprivation and elevated corticosterone, but little or no deficit in size at fledging. in ten cohorts observed for up to 16 years, juni ...201323305448
evidence for asymmetrical divergence-gene flow of nuclear loci, but not mitochondrial loci, between seabird sister species: blue-footed (sula nebouxii) and peruvian (s. variegata) boobies.understanding the process of speciation requires understanding how gene flow influences divergence. recent analyses indicate that divergence can take place despite gene flow and that the sex chromosomes can exhibit different levels of gene flow than autosomes and mitochondrial dna. using an eight marker dataset including autosomal, z-linked, and mitochondrial loci we tested the hypothesis that blue-footed (sula nebouxii) and peruvian (s. variegata) boobies diverged from their common ancestor wit ...201323614045
better stay together: pair bond duration increases individual fitness independent of age-related variation.prolonged pair bonds have the potential to improve reproductive performance of socially monogamous animals by increasing pair familiarity and enhancing coordination and cooperation between pair members. however, this has proved very difficult to test robustly because of important confounds such as age and reproductive experience. here, we address limitations of previous studies and provide a rigorous test of the mate familiarity effect in the socially monogamous blue-footed booby, sula nebouxii, ...201424827435
enhanced male coloration after immune challenge increases reproductive potential.in many animal species, females select a mate on the basis of the expression of secondary sexual traits. a prevalent theory suggests that male ornaments are reliable indicators of immunocompetence, because the cost of immune function prevents cheating. however, sexual signalling is a component of male reproductive effort, and an immune challenge may also alter his perceived future prospects and hence signalling effort. in this study, blue-footed booby males (sula nebouxii) were inoculated with a ...201424846565
comparative ectoparasite loads of five seabird species in the galapagos islands.in this paper we describe the ectoparasitic lice (insecta: phthiraptera) found on 5 species of seabirds (magnificent frigatebird fregata magnificens; great frigatebird fregata minor ; nazca booby sula granti ; blue-footed booby sula nebouxii ; and red-footed booby sula sula ) on the galapagos archipelago. we found 9 species of ectoparasitic lice: 5 species of pectinopygus ischnocerans, 1 infesting each host; 2 species of colpocephalum amblyceran lice, 1 on each frigatebird species; and 2 shared ...201424911632
lineage sorting in multihost parasites: eidmanniella albescens and fregatiella aurifasciata on seabirds from the galapagos islands.parasites comprise a significant percentage of the biodiversity of the planet and are useful systems to test evolutionary and ecological hypotheses. in this study, we analyze the effect of host species identity and the immediate local species assemblage within mixed species colonies of nesting seabirds on patterns of genetic clustering within two species of multihost ectoparasitic lice. we use three genetic markers (one mitochondrial, coi, and two nuclear, ef1-α and wingless) and maximum likelih ...201526380662
tough beginnings on galapagos, baby blue footed booby. 201525758758
viability of booby offspring is maximized by having one young parent and one old parent.it is widely expected that the quality of offspring will vary with the age of their parents and that this variation should influence animals' choice of mates. however, theoretical predictions for age effects are contradictory and, to our knowledge, we do not know for any wild animal how the quality of offspring is affected by both parents' ages across their lifespans, or whether mothers' and fathers' ages interact. we tackled this question using long-term data on a highly philopatric, insular po ...201526221951
female infidelity is constrained by el niño conditions in a long-lived bird.explaining the remarkable variation in socially monogamous females' extrapair (ep) behaviour revealed by decades of molecular paternity testing remains an important challenge. one hypothesis proposes that restrictive environmental conditions (e.g. extreme weather, food scarcity) limit females' resources and increase ep behaviour costs, forcing females to reduce ep reproductive behaviours. for the first time, we tested this hypothesis by directly quantifying within-pair and ep behaviours rather t ...201627119773
lead, cadmium and mercury in the blood of the blue-footed booby (sula nebouxii) from the coast of sinaloa, gulf of california, mexico.we used blood samples of the blue-footed booby, considering sex (female and male) and age-class (adult and chick) of individuals at different breeding stages during two breeding seasons (2010-2011 and 2011-2012) in isla el rancho, sinaloa, to determine lead, cadmium, and mercury concentrations. lead and cadmium concentrations were below our detection limit (0.05 and 0.36ppm, respectively). a higher concentration of mercury was found in early stages of breeding, likely related to changes in mercu ...201627318761
local and interannual variations in mercury and cadmium in eggs of eight seabird species of the sinaloa coast, méxico.mercury (hg) and cadmium (cd) concentrations in eggs of 8 seabird species inhabiting 5 coastal ecosystems in sinaloa, méxico were determined during 2 breeding seasons (2012 and 2013): blue-footed booby (sula nebouxii), brown booby (sula leucogaster), double-crested cormorant (phalacrocorax auritus), magnificent frigatebird (fregata magnificens), brown pelican (pelecanus occidentalis), royal tern (thalasseus maximus), laughing gull (leucophaeus atricilla), and heermann's gull (larus heermanni). t ...201626887632
high quality diet improves lipid metabolic profile and breeding performance in the blue-footed booby, a long-lived seabird.understanding the role of diet in the physiological condition of adults during reproduction and hence its effect on reproductive performance is fundamental to understand reproductive strategies in long-lived animals. in birds, little is known about the influence of the quality of food consumed at the beginning of the reproductive period and its short-term effects on reproductive performance. to assess the role of diet in the physiological condition of female blue-footed booby, sula nebouxii (bfb ...201829462199
correction: high quality diet improves lipid metabolic profile and breeding performance in the blue-footed booby, a long-lived seabird.[this corrects the article doi: 10.1371/journal.pone.0193136.].201829672585
experiencing el niño conditions during early life reduces recruiting probabilities but not adult survival.in wild long-lived animals, analysis of impacts of stressful natal conditions on adult performance has rarely embraced the entire age span, and the possibility that costs are expressed late in life has seldom been examined. using 26 years of data from 8541 fledglings and 1310 adults of the blue-footed booby (sula nebouxii), a marine bird that can live up to 23 years, we tested whether experiencing the warm waters and food scarcity associated with el niño in the natal year reduces recruitment or ...201829410788
mate selection based on labile traits affects short-term fitness in a long-lived seabird.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 (δ15n), and foraging habitat (δ13c) 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 reproductiv ...202032126956
Displaying items 1 - 41 of 41