James Joseph Roper

Ars Artium Consulting

While bird diversity in the Atlantic Forest can be considered well-known, how the communities have been affected by deforestation and habitat fragmentation is not. We studied birds in 10 forest fragments of distinct sizes (all originally within the Atlantic Forest) in southern Bahia. In 5,391 bird encounters, we found 251 species, with 46 endemics...

Population dynamics are influenced by environmental variability and understanding abundance and persistence of individuals and populations is a fundamental goal of population ecology. Thus, estimating demographic parameters to identify the factors important for population variability is required to understand temporal and spatial dynamics. The stre...

The status of endemic and threatened birds of the Brazilian Atlantic Forest remains poorly understood. Citizen science offers information that helps fill this gap. In southern Brazil, traditional science was carried out in 15 of 50 municipalities in western Paraná state, reporting 82 endemic and 25 threatened species in a total of 467. WikiAves, th...

The mostly neotropical genus Philornis Meinert is associated with a variety of birds, where larvae can be free-living coprophagous, free-living semi-hematophagous, or subcutaneous hematophagous. The genus is taxonomically complicated because characters of some species are variable while others are more constant. Although most described Philornis sp...

We measured bird diversity over an 800 m range in altitude to test the factors that influence changes in diversity, in the Atlantic Forest in the state of São Paulo, Brazil. We counted forest birds in nine 100 m transects comprising three-point counts, the center of each separated by 200 m. A total of 108 species were found, and diversity was distr...

Cooperative breeding is rare in shorebirds, and when found is thought to be due to polygamous mating (cooperative polygamy). Here we describe the social structure of cooperatively breeding groups in Southern Lapwing Vanellus chilensis and test the prediction that offspring sex ratio is skewed towards the sex that helps. The social groups consisted...

Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morpho- logical variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological d...

Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data...

How are personalities maintained in wild animal populations? A possible mechanism is the existence of trade-offs between fitness components (survival and reproductive success) among behavioural types. We investigated this trade-off in white-rumped swallows ( Tachycineta leucorrhoa ) by capturing adults and monitoring their reproduction over time. W...

Food limitation may interact with nest predation and influence nesting patterns, such as breeding season length and renesting intervals. If so, reproductive effort should change with food availability. Thus, when food is limited, birds should have fewer attempts and shorter seasons than when food is not limiting. Here we experimentally test that in...

Many species of hummingbirds are sexually monochromatic. This is surprising because in all hummingbird species parental care is carried out by females, while males are promiscuous, and this mating system is usually associated with some form of sexual dimorphism. To study sexual selection in monochromatic species, the identification of sex is a prer...

Studies about personalities in wild animals usually focus on five categories of behavioral traits that do not easily accommodate all aspects of parental care, a class of behaviors with direct consequence to reproductive success. Parental care can vary consistently between individuals and constitute parenting styles. Here we investigate the consiste...

Theory predicts that, even within the same population, birds may vary their breeding investment with age. This may be due to an improvement in individual quality of old birds in body condition, foraging and in nesting experience. Birds commonly signal age and individual quality to potential mates and competitors through plumage colour. Young male a...

Poorly known species may be cryptically endangered, especially when they inhabit fragmented and threatened habitats. Heart-tongued frogs (genus Phyllodytes, family Hylidae, Lophyohylinae) comprise 17 species of poorly known frogs that have obligatory associations with tank bromeliads. The distributions of all species are restricted to a small, extr...

Here we present a brief review on how the loss of fauna can cause a concomitant loss in plant diversity in the state of Espírito Santo, focusing on the context of current habitat loss and fragmentation and the importance of the mutualistic interactions between animals and plants. We discuss the main groups of fauna that are involved in pollination...

Here we describe novel post-dispersal seed predation by Atlantic Forest squirrels (Guerlinguetus ingrami). We show that the squirrel preys on seeds defecated by lowland tapirs (Tapirus terrestris) in the Atlantic Forest, southeastern Brazil. The squirrel consumed seeds in tapir feces at a latrine, including Spondias macrocarpa, S. venulosa and Elae...

Coastal marine protected areas (MPAs) can adversely affect the livelihood of those dependent upon those areas for their source of food or income, especially poor fishermen. MPAs can create poverty traps by prohibiting or limiting access to resources. Avoiding the poverty trap requires understanding of socioeconomic sustainability of fishing activit...

Aim: Among the world’s three major nectar-feeding bird taxa, hummingbirds are the most phenotypically specialized for nectarivory, followed by sunbirds, while the honeyeaters are the least phenotypically specialized taxa. We tested whether this phenotypic specialization gradient is also found in the interaction patterns with their floral resources....

Secondary transport of introduced species can be important in dispersing potentially invasive species, and vectors of transport are often the fouled hulls of small fishing and recreational boats. Likelihood of transport depends on many factors, including resistance of the species to drag forces due to boat velocity and resistance to desiccation. To...

We examine phytoplankton community structure and how it is influenced by commercial tilapia (Oreochromis niloticus L.) cage farming in three tropical lakes in eastern Brazil. Sampling occurred during both the wet and dry seasons for two treatments – within tilapia cages and outside the cages in the lake. Total ammonia, total phosphorus, chlorophyll...

We studied nesting in marked pairs of Star-Throated Antwrens (Rhopias gularis) over 3 years to examine whether breeding traits in subtropical Brazil are more similar to temperate patterns of breeding than is typical of the patterns observed within the mostly tropical Thamnophilidae. This Antwren is socially monogamous and permanently territorial, a...

Information on breeding biology of birds is fundamental for the understanding of life history evolution and conservation. This information is only beginning to accumulate for Neotropical birds but the southern subtropics are still overlooked. Here we describe the breeding biology of passerines in subtropical Brazilian Atlantic Forest. We monitored...

The island rule suggests that, when mainland animals are isolated on islands, large animals tend to become smaller, while small animals tend to become larger. A small frog in eastern Brazil, Phyllodytes luteolus (Wied-Neuwied, 1824), is widely distributed in association with bromeliads. At the end of the last glaciation, parts of the mainland becam...

Nest prospecting, that is, visiting potential fu- ture nest sites, may be a widespread bird behavior. Here we describe apparent prospecting while nesting by white- rumped swallows (Hirundinidae, Aves). In southern Brazil, birds tagged with passive-integrated transponders (PIT- tags) and breeding in nest boxes with PIT-tag readers: (1) often visited...

The Southern Lapwing (Vanellus chilesnis) is a common bird in Southern America and commonly found in any large open areas, including agriculture and urban. The lapwing is a facultative cooperative breeder and aggressively defends its breeding territory. Thus, the breeding system and their consequences for reproductive success are interesting for ev...

Edge effects have been studied extensively in fragmented landscapes, often with conflicting findings. Edge effects may also be important in other situations, such as linear clearings (e.g. along roads, power lines or train tracks). We tested for responses of small mammals to a narrow (c. 10 m) linear clearing created by a railway in the largest are...

Estimar a riqueza e a diversidade de espécies em ecossistemas naturais é um requisito central em pesquisas de conservação da natureza. Neste estudo foi comparada a riqueza da avifauna estimada para três ambientes antropizados inseridos em área de Mata Atlântica de Tabuleiro, a partir de curvas de acúmulo de espécies, e foi comparada a eficiência de...

Food limitation may interact with nest predation and influence nesting patterns, such as breeding season length and renesting intervals. If so, reproductive effort should change with food availability. Thus, when food is limited, birds should have fewer attempts and shorter seasons than when food is not limiting. Here we experimentally test that in...

Food limitation may interact with nest predation and influence nesting patterns, such as breeding season length and renesting intervals. If so, reproductive effort should change with food availability. Thus, when food is limited, birds should have fewer attempts and shorter seasons than when food is not limiting. Here we experimentally test that in...

Here we describe a small mammal community in nonfragmented Atlantic Forest in southern Brazil. A total of 146 individuals were live captured on the ground and in trees (total effort: 5600 trap-nights). Twelve species were identified by morphology, and identification of seven species was confirmed by DNA barcoding. Most species were terrestrial, wit...

Abstract. – The Peruvian Plantcutter (Phytotoma raimondii, Cotingidae), endemic to northwestern Peru, is endangered due to increasing habitat loss. Here, we describe the breeding cycle from which we attempt to infer life history patterns and possible conservation strategies. We captured and marked 16 pairs of plantcutters in 2011 at the Pómac Fores...

La estimación de parámetros poblacionales para especies amenazadas es crucial para la ejecución de prácticas adecuadas de conservación que conlleven a la recuperación y mantenimiento de las mismas. La Cortarrama Peruana (Phytotoma raimondii) es una especie en peligro y restringida al noroeste del Perú, de la que se conoce muy poco respecto a su tam...

Several methods are available to capture cavity-nesting birds but not all are equally easy to use. Here we propose an improved method, in which we use a modified fish basket placed over the opening to the nest using an extendible pole. When a bird enters the basket trap, the entrance to the trap is closed by pulling on a string that shuts the door...

Song learning in birds has been intensively studied, mostly in the suborder Oscines. While studying the black-cheeked gnateater Conopophaga melanops (Suboscine) in southern Brazil nestling vocalizations were observed. Adult and nestlings vocalizations were described and compared to examine age-specific variation in song structure. Nestling vocaliza...

Here we described some observations on the reproduction of Phytotoma raimondii collected in the year 2012 during an ongoing research for estimating reproductive success inside the protected area ‘Bosque de Pomac’ Historical Sanctuary. We report the first complete nesting intervals for the species and include additional descriptive information about...

In the northern hemisphere, bird counts have been fundamental in gathering data to understand population trends. Due to the seasonality of the northern hemisphere, counts take place during two clearly defined moments in time: the breeding season (resident birds) and winter (after migration). Depending on location, Neotropical birds may breed at any...

Survival and consequent implications for population dynamics in the subtropical Striped Frog Hypsiboas leptolineatus was studied for 1 year in the southern Brazilian state of Paraná. By means of capture‐marking‐recapture, we estimated survival and capture probabilities in an open population. A total of 583 captures of 374 individuals, comprising 96...

The possibility of assessing endogenous adrenal activity in the collared peccary (Pecari tajacu) was tested by using an adrenocorticotropic hormone (ACTH) challenge in a fecal glucocorticoid metabolite (FGM) assay. Feces were collected from 12 captive adult male peccaries beginning 48 hr prior to challenge; six of these animals received the challen...

We report the nesting biology of birds in the Cerrado (savanna, both natural and anthropic) of the Federal District of central Brazil, with emphasis on nests, eggs, nesting periods, brood patches, reproductive behavior and period of nesting activity. With 196 nests of 42 species found from 2002 through 2009, we found that most species nested from S...

Three primates (Alouatta caraya, Sapajus nigritus and Sapajus cay) are found in riparian areas of the Upper Paraná River in southern Brazil. Population densities of these three species were estimated from October 2004 through September 2005 by counts on linear transects in riparian forests on two riverine islands and adjacent shores in the states o...

Editor's note: This paper is a contribution to the proceedings of the 3rd International Invasive Sea Squirt Conference held in Woods Hole, Massachusetts, USA, on 26–28 April 2010. The conference provided a venue for the exchange of information on the biogeography, ecology, genetics, impacts, risk assessment and management of invasive tunicates worl...

Sibling competition may reduce reproductive success as well as growth and future survival of the offspring involved. In birds, this may influence the evolution of reproductive strategies concerning how adults may control or limit such competition. For example, it is hypothesized that size hierarchy in the young may reduce sibling competition and re...

Exotic species invasions are one of the greatest threats to marine systems and ascidians have many characteristics that favor transport, colonization and establishment into new regions. Didemnum perlucidum is a widespread species that has been introduced into tropical ports around the world. Here we examine the colonizing ability of D. perlucidum b...

Nest predation is the most important cause of nest failure in most birds and latitudinal differences in nest predation rates and life histories suggest that nest predation has been influential in life history evolution. All else equal, natural selection should favor reduction of nest predation, yet evidence is equivocal. We used Monte Carlo simulat...

Este trabalho teve por objetivo acompanhar e analisar as interações inter e intra-específicas de beija-flores e como estas interações mudaram ao longo do ano. O estudo foi realizado em um remanescente de floresta no município de Piraquara, Paraná. Beija-flores foram filmados mensalmente entre março de 2008 e abril de 2009. Foi possível identificar...

Population structure and dynamics of the black-cheeked gnateater (Conopophaga melanops) were studied at Salto Morato Nature Reserve, in Paran, southern Brazil, from October 2006 to September 2007. Territory size and population density, breeding season (timing and length), reproductive success and annual survival rates were estimated from sightings...

Populations of Asterina stellifera Mobius, 1859 are declining in southern Brazil and today the species is on the Brazilian list of endangered species. Here we experimentally investigate the ecological role played by A. stellifera as a predator on the rocky substrate community by increasing densities of this species. Starfish taken from other, nearb...

Theory predicts that when males provision females with nuptial gifts that include nutrients, the degree of polyandry should be positively correlated with the size or quality of the gift. This is because larger and more nutritious gifts tend to increase female refractory period, reducing the chances the female will remate soon. This decreases the li...

Playback of recorded bird songs is often used to attract birds for sighting as well for captures. The combined use of playbacks and captures may in fact change the behavior of birds such that the response to playbacks does not reflect responses to natural songs. Here we studied whether the use of playbacks changes detectability of the birds. Birds...

Sexual and asexual reproduction and associated population dynamics were investigated in the colonial ascidian Didemnum rodriguesi Rocha & Monniot, 1993 (Didemnidae) in southern Brazil. Investment in sexual (production of new individuals) and asexual (colony growth) reproduction was compared between seasons. Permanently marked quadrats were repeated...

Biscutate swift Streptoprocne biscutata nests are usually built on protected rocky cliff walls. Birds often renest at the same location. Remains of previous nests may offer information about potential nests and quality of nest-sites. Here, we experimentally study nest-site selection to test the hypothesis that information from previous nests is use...

Annual patterns of fecal corticoid excretion were analyzed in the threatened Red-tailed parrot (Amazona brasiliensis) in captivity. Corticoid concentration over the 15 months of the study (mean +/- standard error, 12.6 +/- 0.32 ng g(-1), n = 585) was lowest around May (the southern Fall), and greatest around September (late winter), just prior to t...

Maternal care of offspring is ubiquitous among primates, but its duration varies across species due to factors such as dispersal patterns and social dynamics, which influence opportunities for and potential benefits of maternal investment in older offspring, respectively. We examined mother-offspring associations in wild northern muriquis (Brachyte...

Dillapiol, a phenylpropanoid isolate from essential oils of leaves of Piper aduncum (Piperaceae), has insecticidal, fungicidal and antimicrobial activities. The insecticidal activity of dillapiol was tested in vivo on the larvae and pupae of Aedes aegypti, the mosquito vector of dengue. Specifically, the effect of dillapiol on the formation of micr...

Ports are important locations for the introduction of marine species, while marinas and pontoons often serve as secondary habitats for these species. In a marina near Paranaguá Port, a major international port in southern Brazil, the encrusting community was studied to (i) identify possibly introduced species, and (ii) examine the use of artificial...

The Rufous Hornero (Furnarius rufus: Family Furnariidae), common in southern Brazil, is a territorial, sexually monomorphic bird in which pairs sing duets. This family of birds is known for its lack of sexual dimorphism and for the simplicity of its song types. Here I report that each sex consistently sings a distinct song during the duet: the song...

Os cromossomos e a variação de conteúdo de DNA nuclear foram estudados em sete amostras de Synbranchus marmoratus das bacias dos rios Paraguai e Paraná com o objetivo de avaliar se diferenças no cariótipo e no conteúdo de DNA nuclear poderiam fornecer informações para a caracterização de linhagens evolutivas independentes no gênero e para a elabora...

Successful reproduction for birds in systems with high nest predation rates may be explained by two alternatives. The first hypothesis is that nest-predation is avoided, perhaps by nest-site or territory selection, parental behavior and so on. This hypothesis renders the prediction that within-pair consistency, or repeatability, in nesting success...

Senna multijuga (Rich.) H. S. Irwin & Barneby (Caesalpinaceae) is a native ornamental tree common in southeastern Brazil and susceptible to seed damage due to bruchines. To identify seed predators and determine their population cycles, fruits from five trees were collected in 2000 and 2001 and stored in a green house until adult emerged. Seed beetl...

Phenological patterns in tropical plants usually are associated with the clear seasonality of rainfall associated with very different wet and dry seasons. In southern Brazil, in a subtropical forest with no pronounced dry season (average annual precipitation = 1389 mm, minimum monthly average c. 75 mm), plant phenology was studied to test for patte...

Small clutches in tropical species of passerine birds may be a response to nest predation. The Skutch hypothesis predicts that nest predation increases with activity at nests, and activity at nests is assumed to increase with clutch size. This suggests that predation should be greatest when activity is greatest, all else being equal. If true, then...

Nest predation is a major cause of reproduction failure for many species of passerine birds. Thus, nest predation has received much attention regarding its influence on the evolution of avian life histories and nest-site and habitat selection. Differences between tropical and temperate birds in these life history and nest-site traits have often bee...

Audubon's Hermit Thrushes (Catharus guttatus auduboni) in central Arizona have a low nesting success (7 to 20%) due almost exclusively to nest predation. We examine the sites chosen for nesting and compare them to nonuse sites randomly selected within the vegetation types associated with nests. Hermit Thrush nest sites differ from nonuse sites prim...

Orientador : James Joseph Roper Dissertaçăo (mestrado) - Universidade Federal do Paraná, Setor de Cięncias Biológicas, Programa de Pós-Graduaçăo em Ecologia e Conservaçao. Defesa: Curitiba, 2007 Inclui bibliografia

Thesis (M.S.)--Arizona State University, 1989. Vita. Includes bibliographical references (leaves [40]-44).