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Biological invasions cause species extinction but can also provide benefits. Wetlands, such as salt marshes, include little-known but important ecosystems that are sometimes severely invaded by exotic plants. Salt marshes in eastern South America are increasingly impacted by invasions of the African grass Urochloa arrecta. This study investigated the appearance of a population of the mangrove rail Rallus longirostris in areas dominated by U. arrecta and its disappearance with the eradication of this plant. We monitored four areas (54.47 ha) in the Guaratuba Bay estuary in southern Brazil, from 2006 to 2022, two of which contained four patches of U. arrecta as the dominant species. In 2012, we started to eradicate U. arrecta with mechanical management, and in 2020, it was eradicated locally. We recorded R. longirostris for the first time within a patch of U. arrecta in 2007. In subsequent years we saw the species in two other patches of the exotic plant. Rallus longirostris was no longer observed once U. arrecta was eradicated. Differences in patch occupancy between invaded and uninvaded habitats observed for R. longirostris and Pardirallus nigricans, and the disappearance of R. longirostris following the exotic plant management suggest competitive advantage and/or differential habitat preference and population density as hypotheses to explain observed patterns. The invasion of U. arrecta can increase the local populations of R. longirostris. Since this bird is not endangered, we encourage the management of U. arrecta because of its impact on salt marshes, including an endemic endangered bird. Supplementary information: The online version contains supplementary material available at 10.1007/s13157-022-01642-7.

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This study analyzed trace elements (As, Ba, Cd, Cu, Fe, Mn, Pb, Zn) and stable isotopes of carbon and nitrogen in egg yolk samples of female green turtles that nested in Rocas Atoll, Brazil, in 2017 and 2018. The trace elements concentration varied between years, with higher concentrations in 2017, suggesting that the nesting groups come from different foraging sites. The isotopic data indicated high overlap between years (73%), leading to an ambiguous interpretation on the turtles' foraging site. The Normalized Total Load presented a low association (0.01 < R2 < 0.41) with the stable isotopes. The Normalized Total Load that represents the trace element load in egg yolk is a holistic approach that can be applied elsewhere to predict ecotoxicology pathways in any animal species. We recommend a continuous monitoring to verify how the trace elements load behave in the nesting green turtles on Rocas Atoll.

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This study presents the first report on the concentration of trace elements (Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn) in the blood and egg fractions of green turtles from Rocas Atoll, a pristine nesting site in NE Brazil. The highest concentrations of all elements were in the blood or shell samples. In order, iron, Zn, Cu, Al and As presented the highest concentrations in all tissues. The nonessential trace elements were below the limit of detection for more than 50% of the yolk (Al, Cd and Pb) and albumen samples (Al, As, Ba, Cd and Pb). This study will serve as a baseline reference for future monitoring of the ecotoxicology of breeding green turtles in the southwestern Atlantic Ocean.

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ABSTRACT We report for the first time great quantities of floating Sargassum to Serranilla Bank, in the Central Caribbean. The island is an important nesting site for sea turtles, and by the time the Sargassum wave arrived, the baby turtles were disclosing. Due to the thick mat of Sargassum along the beach, the baby turtles may have troubles to reach the ocean.

RESUMEN Se reporta por primera vez una gran cantidad de Sargassum flotante en Cayo Serranilla, en el Caribe central. La isla es un sitio importante para anidamiento de tortugas marinas, y al momento de la llegada del Sargassum, los nidos estaban eclosionando. Debido al espeso tapete de algas en la playa, las tortuguas pueden tener problemas en llegar al mar.

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The reproduction of titanosaur dinosaurs is still a complex and debated topic. Their Late Cretaceous nesting sites are distributed worldwide and their eggs display substantial morphological variations according to the parent species. In contrast to the typical 1.3-2.0 mm thick shells common to eggs of most titanosaur species (e.g., those that nested in Auca Mahuevo, Tama, Totesti or Boseong), the Cretaceous Sanagasta eggs of Argentina display an unusual shell thickness of up to 7.9 mm. Their oviposition was synchronous with a palaeogeothermal process, leading to the hypothesis that their extra thick eggshell was an adaptation to this particular nesting environment. Although this hypothesis has already been supported indirectly through several investigations, the mechanical implications of developing such thick shells and how this might have affected the success of hatching remains untested. Finite element analyses estimate that the breaking point of the thick-shelled Sanagasta eggs is 14-45 times higher than for other smaller and equally sized titanosaur eggs. The considerable energetic disadvantage for piping through these thick eggshells suggests that their dissolution during incubation would have been paramount for a successful hatching.

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ResumenEl éxito de anidación ha sido un indicador para evaluar los cambios ambientales que afectan el éxito reproductivo de aves, ya que permite analizar cambios que ocurren en la natalidad. En el presente estudio analizamos el éxito de anidación de Turdus grayi en el Centro Ecológico Recreativo "El Zapotal", Chiapas. Durante la temporada reproductiva del 2015, evaluamos las características del hábitat, presentes en los sitios de anidación a través de la búsqueda intensiva de nidos. Localizamos 56 nidos de los cuales, 27 (48.2 %) fueron exitosos y 29 (51.7 %) fueron fallidos. La mayoría de los nidos no exitosos (19) fueron depredados mientras que 8 (27.6 %) fueron abandonados y 2 (6.9 %) parasitados. El éxito de anidación fue de 46 %. La depredación fue el principal factor del fallo de los nidos. La incubación fue la etapa más susceptible a la depredación.Identificamos que las variables del sitio de anidación operaron a dos escalas espaciales: local y parche del nido. A través del análisis de regresión logística binaria se obtuvo un modelo para cada escala, el cual predijo qué variables incrementaron la probabilidad de éxito de anidación. Además realizamos un análisis de regresión logística multivariante para descartar posibles interacciones entre las variables. A escala local encontramos que la altura del nido a un intervalo de 4.2-5.1 m de altura incrementó el éxito del nido, mientras a escala parche del nido, la probabilidad de éxito de anidación fue mayor en los sitios con una densidad ≥ 12 árboles. Los análisis indicaron que la probabilidad de éxito de anidación no presentó una relación entre la escala local y parche del nido. Lo que sugiere un desacoplamiento de escalas y mecanismos. Por lo cual los cambios que ocurren en las variables que intervienen a escala local parecen no interferir en la escala de parche del nido. Los resultados obtenidos mostraron que la variación en las características de los sitios de anidación podría influir en la depredación además de que la depredación podría haberse presentado de manera aleatoria ya que los nidos que presentaron probabilidades medias y altas de ser exitosos fallaron por esta causa. De este modo, con el fin de comprender los factores, mecanismos y características de historia de vida que influyen en el éxito de anidación, sugerimos que además de las variables ambientales, los estudios futuros deberán considerar el comportamiento de las aves anidantes.

AbstractNesting success has been a surrogate to assess environmental changes that affect the reproductive success of birds, and to analyze changes that influence natality. We analyzed the nesting success of Turdus grayi at "El Zapotal" Recreational Ecological Preserve, Central Chiapas. During the 2015 breeding season, we intensively searched for active nests and evaluated habitat characteristics. We located a total of 56 nests of which 27 (48.2 %) were successful and 29 (51.7 %) were unsuccessful. Most unsuccessful nests (19) were depredated, while 8 (27.6 %) were abandoned and 2 (6.9 %) parasitized. Nesting success was 46 %. Depredation was the main mechanism of nest failure, mostly during incubation. We identified operating variables at site and patch scales. Through analysis of binary logistic regression models for each scale, we predicted which variables increased the probability of nesting success. We also performed a multivariate logistic regression analysis to rule out possible interactions among variables. At nest scale we found that nest height, ranging 4.2 - 5.1 m had increased nesting success, while at patch scale, the probability of nest success was greater at sites with a tree density ≥ 12. Our results indicated that the probability of nesting success did not show a relationship between scales. We suggest a decoupling between scales and mechanism. Thus, habitat changes occurring at local scale did not seem to interfere with the patch scale. Also, our results showed that variation in characteristics at nest scale could also influence depredation, when depredation had been presented at random, since nests with medium and high probability of being successful, failed also for this reason. Thus, in order to understand the factors, mechanisms and life history characteristics influencing nesting success, we suggest that in addition to the environmental variables, future studies should also consider the bird nesting behaviour. Rev. Biol. Trop. 65 (3): 925-938. Epub 2017 September 01.

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In birds, the environmental variables and intrinsic characteristics of the nest have important fitness consequences through its influence on the selection of nesting sites. However, the extent to which these variables interact with variables that operate at the landscape scale, and whether there is a hierarchy among the different scales that influences nest-site selection, is unknown. This interaction could be crucial in burrowing birds, which depend heavily on the availability of suitable nesting locations. One representative of this group is the burrowing parrot, Cyanoliseus patagonus that breeds on specific ravines and forms large breeding colonies. At a particular site, breeding aggregations require the concentration of adequate environmental elements for cavity nesting, which are provided by within ravine characteristics. Therefore, intrinsic ravine characteristics should be more important in determining nest site selection compared to landscape level characteristics. Here, we assess this hypothesis by comparing the importance of ravine characteristics operating at different scales on nest-site selection and their interrelation with reproductive success. We quantified 12 characteristics of 105 ravines in their reproductive habitat. For each ravine we quantified morphological variables, distance to resources and disturbance as well as nest number and egg production in order to compare selected and non-selected ravines and determine the interrelationship among variables in explaining ravine differences. In addition, the number of nests and egg production for each reproductive ravine was related to ravine characteristics to assess their relation to reproductive success. We found significant differences between non-reproductive and reproductive ravines in both intrinsic and extrinsic characteristics. The multidimensional environmental gradient of variation between ravines, however, shows that differences are mainly related to intrinsic morphological characteristics followed by extrinsic variables associated to human disturbance. Likewise, within reproductive ravines, intrinsic characteristics are more strongly related to the number of nests. The probability of producing eggs, however, was related only to distance to roads and human settlements. Patterns suggest that C. patagonus mainly selects nesting sites based on intrinsic morphological characteristics of ravines. Scale differences in the importance of ravine characteristics could be a consequence of the particular orography of the breeding habitat. The arrangement of resources is associated to the location of the gullies rather than to individual ravines, determining the spatial availability and disposition of resources and disturbances. Thus, nest selection is influenced by intrinsic characteristics that maximize the fitness of individuals. Scaling in nest-selection is discussed under an optimality approach that partitions patch selection based on foraging theory.

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Titanosauria is a globally distributed clade of sometimes extremely large Mesozoic herbivorous sauropod dinosaurs. On the basis of current evidence these giant dinosaurs seem to have reproduced in specific and localized nesting sites. However, no investigations have been performed to understand the possible ecological and geological biases that acted for the selection of these nesting sites worldwide. In this study, observations were performed on the best-known Cretaceous nesting sites around the world. Our observations strongly suggest their eggs were incubated with environmental sources of heat, in burial conditions. Taking into account the clutch composition and geometry, the nature and properties of the sediments, the eggshells' structures and conductance, it would appear that titanosaurs adopted nesting behaviors comparable to the modern Australasian megapodes, using burrow-nesting in diverse media and mound-building strategies.

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The more common lodger bee occurring in the dry forest of Costa Rica, Centris bicornuta Muscáry), has been observed nesting in new nest cavities drilled into wooden blocks placed next to cavities used by another female within 2-3 days. In contrast, new nest cavities placed in similar areas with no nesting Centris nearby were not used for weeks. These observations suggest that the presence of nesting bees may play a role in nest site selection. To confirm our observations, new nest cavities were placed in areas with or without nesting. We found nest initiation in newly placed nest cavities only in areas where bees were actively nesting. To examine the possibility that nesting locations are not unique, we placed new nest cavities in new locations either with (a) a number of completed nest cavities or (b) placed alone. Within three days we only found bees nesting in the newly placed nest cavities in situation "a". The results suggested that odor might be involved. We next compared nesting in new cavities placed alone with cavities contaminated with either (a) nest entrance plug material, (b) nest nectar, (c) nest pollen or (d) a combination of pollen and nectar. Nesting was significantly low in cavities placed next to cavities with nest entrance plug material (a), and high in cavities placed next to cavities "b, c, or d". The results suggest that pollen and /or nectar odor play a role in the location of potential nest sites.

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Turtle species in which the sex determination is dependent of incubation temperature, the nest site and the laying moment will affect more than embryo sex determination. The influence of the laying site extends all over the embryonic development, affecting hatching weight and size. The time of the egg-laying will bring consequences to the nest thermal environment, as the temperature and humidity change throughout the year. The humidity will be decisive in gaseous and hydric exchanges between eggs and the environment, affecting yolk absorption and embryo growth. Floods and inundation are important factors related to nest loss in freshwater turtle species. Egg laying at the appropriated time makes a safe incubation possible, without the interference of nest inundation and subsequent embryo death. The nest predation varies according to the egg-laying site, type and abundance of predator and nest depth. The choice of areas in the middle of vegetation, where the predation rate is generally smaller, is not always the most used strategy by turtles, since this procedure can decrease the hatching success or provoke changes in sex ratio.

Para as espécies de tartaruga que apresentam a determinação sexual dependente da temperatura da incubação o local e o momento da desova, exercem influências que vão além da definição do sexo dos embriões. A influência do local da desova se estende a todo o desenvolvimento embrionário afetando o comportamento e o tamanho dos filhotes. O momento em que ocorre a desova trará conseqüências ao ambiente térmico dos ninhos à medida que a temperatura e a umidade variam ao longo do ano. A umidade será decisiva nas trocas hídricas e gasosas entre os ovos e o meio afetando a absorção do vitelo e o crescimento dos embriões. As cheias e os alagamentos são importantes fatores de perda de ninhos nas espécies de tartaruga de água doce. A desova no momento adequado possibilita uma incubação segura, sem a interferência de alagamentos dos ninhos e conseqüente morte dos embriões. A predação dos ninhos varia de acordo com o local da desova, o tipo e a abundância de predadores e a profundidade da câmara de ovos. A escolha de pontos de desova no interior da vegetação, onde a taxa de predação é geralmente menor, nem sempre é a estratégia mais frequentemente adotada pelas tartarugas, uma vez que esse procedimento pode levar a uma maior exposição das fêmeas aos predadores, à diminuição do sucesso da eclosão ou a alterações na razão sexual provocadas por diferenças na temperatura da incubação.

RESUMO

Para as espécies de tartaruga que apresentam a determinação sexual dependente da temperatura da incubação o local e o momento da desova, exercem influências que vão além da definição do sexo dos embriões. A influência do local da desova se estende a todo o desenvolvimento embrionário afetando o comportamento e o tamanho dos filhotes. O momento em que ocorre a desova trará conseqüências ao ambiente térmico dos ninhos à medida que a temperatura e a umidade variam ao longo do ano. A umidade será decisiva nas trocas hídricas e gasosas entre os ovos e o meio afetando a absorção do vitelo e o crescimento dos embriões. As cheias e os alagamentos são importantes fatores de perda de ninhos nas espécies de tartaruga de água doce. A desova no momento adequado possibilita uma incubação segura, sem a interferência de alagamentos dos ninhos e conseqüente morte dos embriões. A predação dos ninhos varia de acordo com o local da desova, o tipo e a abundância de predadores e a profundidade da câmara de ovos. A escolha de pontos de desova no interior da vegetação, onde a taxa de predação é geralmente menor, nem sempre é a estratégia mais frequentemente adotada pelas tartarugas, uma vez que esse procedimento pode levar a uma maior exposição das fêmeas aos predadores, à diminuição do sucesso da eclosão ou a alterações na razão sexual provocadas por diferenças na temperatura da incubação.

Turtle species in which the sex determination is dependent of incubation temperature, the nest site and the laying moment will affect more than embryo sex determination. The influence of the laying site extends all over the embryonic development, affecting hatching weight and size. The time of the egg-laying will bring consequences to the nest thermal environment, as the temperature and humidity change throughout the year. The humidity will be decisive in gaseous and hydric exchanges between eggs and the environment, affecting yolk absorption and embryo growth. Floods and inundation are important factors related to nest loss in freshwater turtle species. Egg laying at the appropriated time makes a safe incubation possible, without the interference of nest inundation and subsequent embryo death. The nest predation varies according to the egg-laying site, type and abundance of predator and nest depth. The choice of areas in the middle of vegetation, where the predation rate is generally smaller, is not always the most used strategy by turtles, since this procedure can decrease the hatching success or provoke changes in sex ratio.

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Existem poucos dados na literatura sobre a reprodução de Hydromedusa tectifera (Chelidae), e estes se referem a indivíduos de cativeiro. A ecologia reprodutiva da espécie foi verificada através de monitoramentos não sistemáticos entre 1996 e 2002 na Estação Ecológica do Taim, no extremo sul do Brasil, com a intenção de reunir informações sobre a reprodução da espécie em ambiente natural. Foram encontrados 46 ninhos da espécie, entre intactos e predados. As ninhadas tiveram, em média, 11,6 ovos que apresentaram um tamanho médio de 36,5 x 23,9 mm. A média do peso dos ovos foi de 11,1 g e o seu volume individual resultou em uma média de 10148,31 mm³. Os ninhos alcançaram uma profundidade média de 11,1 e 5,8 cm da superfície ao primeiro ovo. A variação do volume dos ovos de um mesmo ninho foi menor (CV = 4,71 por cento) do que entre diferentes ninhos (CV = 12,32 por cento). A largura dos ovos foi positivamente dependente do seu comprimento. Já em uma mesma ninhada, o número de ovos não dependeu do seu tamanho e do seu volume. Foram observadas desovas nos meses de novembro e dezembro, mas a maioria delas ocorreu na segunda quinzena de novembro. A espécie desovou com maior freqüência no período das 18 às 20 horas, e em áreas com certa inclinação do substrato, entre 20º e 30º de declividade. A maior abundância de ninhos foi observada até 5 m de distância da lagoa. Os resultados encontrados demonstram congruência entre os dados obtidos para H. tectifera e aqueles existentes para cágados-de-pescoço-comprido da Austrália e para as espécies de Chelidae do extremo sul do Brasil.

The few available information on the reproductive behavior of Hydromedusa tectifera (Chelidae) are based on captive individuals. The H. tectifera reproductive biology was verified from 1996 to 2002 by non-systematic surveys in the Estação Ecológica do Taim, southern Brazil. Forty-six intact and damaged nests of the species were found. Mean clutch size was 11.6 eggs which exhibited a mean size of 36.5 x 23.9 mm and an average weight of 11.5 g. Individual mean eggs volume resulted an average of 10148.31 mm³. Nests had an average depth of 11.1 and 5.8 cm from the surface to the first egg. The eggs volume variation in the same nest was smaller (CV = 4.71 percent) than among different nests (CV = 12.32 percent). The eggs width was positively dependent of their length. In the same hatch the number of eggs did not depended of their size or volume. Nesting behavior was observed in November and December. The species showed higher frequency for nesting between 6 and 8 p.m., in areas with certain inclination of the substratum, between 20º and 30º of declivity. Higher nest abundance was verified up to 5 m from the lagoon. The results show that the data obtained for H. tectifera are similar to those previously reported for Australian snake-necked turtles and for species of Chelidae from southern Brazil.

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