The relationship between nest location and breeding success in the colonial nesting Azure-winged Magpie Cyanopica cyanus breeding in Japanese Yew Taxus cuspidata tree plantations

Abstract Raptor conservation programs should be based on knowledge of the birds’ ecology in both natural and urban habitats, justifying the inclusion of ecological studies in suburban zones into regional planning initiatives. The objectives of this study were (a) to determine the use by diurnal raptors of the habitat in a suburban area of a city in southern Chile, and (b) to characterize the different zones into five types of environment, and assess their raptor diversity for consideration in territorial planning. Acoustic surveys were conducted in auditory stations in addition to observations from fixed transects and trails. From a total of 161.39 hours of census, we obtained 664 sightings corresponding to ten species of diurnal raptors. The richest environment was dense forest (eight species), followed by grassland (six species), native forest regeneration (five species), shrubs (four species) and exotic tree plantations (three species). We discuss the relationship between the richness of diurnal raptors, the types of environment in the study area, and the spatial location of the sites, as well as the implications for territorial planning to support the conservation of birds of prey in the suburban zone studied.

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Relationships Between Black-Legged Kittiwake Nest-Site Characteristics and Susceptibility to Predation by Large Gulls

The Condor ◽

10.1093/condor/103.4.793 ◽

2001 ◽

Vol 103 (4) ◽

pp. 793-801 ◽

Cited By ~ 4

Author(s):

Melanie Massaro ◽

John W. Chardine ◽

Ian L. Jones

Keyword(s):

Nest Site ◽

Nest Density ◽

Nest Location ◽

Rissa Tridactyla ◽

Nest Sites ◽

Site Characteristics ◽

Risk Of Predation ◽

Breeding Failure ◽

Larus Marinus ◽

The Relationship

Abstract We quantified the relationship between Black-legged Kittiwake (Rissa tridactyla) nest-site characteristics and risk of predation by Great Black-backed (Larus marinus) and Herring (L. argentatus) Gulls at Gull Island, Newfoundland, Canada, during 1998 and 1999. We monitored kittiwake nesting cliffs to identify nest sites attacked by large gulls and compared characteristics of attacked and successful nests among four study plots. We also examined which nest sites were attacked by Herring or Great Black-backed Gulls during calm (≤10 km hr−1) or windy conditions (>10 km hr−1). We found that kittiwake nests on plots with fewer nests were more likely to be attacked by gulls and less likely to fledge young. Nest density and nest location relative to the cliffs' upper edges significantly affected the risk of gull predation. Breeding success was correlated with nest density and ledge width and differed significantly among plots. Regardless of wind conditions both gull species were more likely to attack nests located on upper sections of cliffs than nests on lower sections. However, during calm conditions, nest sites located on narrow ledges were less likely to be attacked by Great Black-backed Gulls. Our results demonstrate that for kittiwake colonies where predation is an important source of breeding failure, the size of subcolonies and nest density affect the survival of kittiwake offspring. Relación entre las Características de los Sitios de Nidificación de Rissa tridactyla y la Susceptibilidad a la Depredación por parte de Gaviotas Resumen. Cuantificamos la relación entre las características de los sitios de nidificación de Rissa tridactyla y el riesgo de depredación por parte de Larus marinus y L. argentatus en la Isla Gull, Newfoundland, Canadá, durante 1998 y 1999. Con el objetivo de identificar los nidos atacados por gaviotas de gran tamaño, monitoreamos acantilados de nidificación de R. tridactyla en cuatro localidades de estudio y comparamos las características de los nidos atacados y exitosos. También examinamos qué nidos fueron atacados por L. marinus o por L. argentatus durante condiciones de viento calmo (≤10 km hr−1) o ventosas (>10 km hr−1). Encontramos que los nidos de R. tridactyla ubicados en localidades con menor número de nidos tuvieron mayor probabilidad de ser atacados y menor probabilidad de criar volantones. Tanto la densidad como la ubicación de los nidos en relación al vértice superior del acantilado afectaron significativamente el riesgo de depredación por gaviotas. El éxito de cría se diferenció significativamente entre localidades y se correlacionó con la densidad de nidos y con el ancho de la plataforma. Independientemente de la velocidad del viento, las dos especies de gaviotas atacaron con mayor probabilidad a los nidos ubicados en las secciones superiores del acantilado que en las secciones inferiores. Sin embargo, durante condiciones de viento calmo, los nidos localizados en plataformas angostas presentaron una menor probabilidad de ser atacados por L. marinus. Nuestros resultados demuestran que para colonias de R. tridactyla en las cuales la depredación de nidos es un factor importante en el fracaso reproductivo, el tamaño de las subcolonias y la densidad de nidos afecta la supervivencia de la progenie de R. tridactyla.

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The Influence of Rainfall on Growth of Rubber Trees in Marginal Area of Northeast Thailand

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.844.7 ◽

2013 ◽

Vol 844 ◽

pp. 7-10

Author(s):

Niramol Sangchanda ◽

Supat Isarangkool Na Ayutthaya ◽

Somyot Meetha ◽

Patcharin Songsri

Keyword(s):

Rubber Tree ◽

Soil Surface ◽

Tree Planting ◽

Annual Rainfall ◽

Tree Plantations ◽

Northeast Thailand ◽

Positive Correlation ◽

Significant Difference ◽

Khon Kaen ◽

The Relationship

Rubber trees grow predominately in the southern and eastern areas of Thailand, where there is the majority of rainfall. However, the rubber tree plantations extend to north and northeastern areas, with lower annual rainfall. The aim of this study was to evaluate the effect of rainfall on growth of rubber tree in northeastern areas of Thailand. The outcome of this work should be helped to indicate the optimum area for rubber tree planting in northeast. The study was undertaken using rubber tree clone RRIM600 by comparing the girth at 150 cm at the soil surface, planted in areas of differing rainfall: in Nongkhai, Chaiyaphum, Khon Kaen, Roiet and Buriram provinces. The sample of 50 trees was selected in 3 plantations per province (150 trees per province). The results found that there was no significant difference in girth of the rubber trees in all areas. However, the rubber trees planted in Nongkhai, where had highest rainfall, had highest growth. Moreover, the relationship between rainfall and growth exhibited a positive correlation, demonstrating that higher rainfall increased the girth of rubber trees.

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Feral pigeons as a nest competitor for a small seabird

10.21203/rs.3.rs-550854/v1 ◽

2021 ◽

Author(s):

Beneharo Rodríguez ◽

Airam Rodríguez ◽

Felipe Siverio ◽

Juan Manuel Martínez ◽

Enrique Sacramento ◽

...

Keyword(s):

Breeding Success ◽

Columba Livia ◽

Pathogen Transmission ◽

Nest Density ◽

Nest Location ◽

Nest Sites ◽

Breeding Failure ◽

Nesting Sites ◽

Calonectris Borealis

Abstract Due to their life-history traits, the petrels are particularly sensitive to predation by introduced species. Therefore, many populations have constricted their original breeding distribution range, currently only occupying predator-free sites. In this scenario, interspecific competition for nesting sites can be detrimental for the petrel’ conservation. Here, we evaluate how the presence of introduced mammals (cats Felis catus and rats Rattus spp.) and potential competitors for nest sites (Cory’s shearwaters Calonectris borealis and feral rock pigeons Columba livia) shape the distribution, breeding density, and breeding performance of the Bulwer’s petrel Bulweria bulwerii on Tenerife, the largest and most densely populated of the Canary Islands. We estimated nest density, assessed the role of nest location and nest characteristics on breeding success, and determined causes of breeding failure by exotic predators and competitors. Nest density was higher in predator-free colonies on marine rocks. Cat presence was the best predictor for nest density, while presence or abundance of competitors had no correlation to nest density. Breeding success varied between years and colonies, but was not related to nest characteristics. Of the unequivocally determined causes of breeding failure, pigeon competition for nests was the most frequent (7.3%), followed by rat predation (6.3%). We also compared petrel and pigeon nest cavities and found a considerable overlap in nesting niche. Our study provides insight on an overlooked impact of the invasive rock pigeon: nest competition with small seabirds. We encourage more research on the effects of pigeons on nest density, disease and pathogen transmission, and vegetation changes within petrel colonies.

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Ant Community Evolution According to Aging in Brazilian Cocoa Tree Plantations

Sociobiology ◽

10.13102/sociobiology.v66i1.2705 ◽

2019 ◽

Vol 66 (1) ◽

pp. 33

Author(s):

Eltamara Souza da Conceição ◽

Terezinha Maria Castro Della Lucia ◽

Antonio De Oliveira Costa Neto ◽

Érica Dos Santos Araújo ◽

Elmo Borges de A. Koch ◽

...

Keyword(s):

Plant Development ◽

Agroforestry Systems ◽

Tree Plantations ◽

Agricultural Activity ◽

Ant Community ◽

Diversity Gradient ◽

Biotic Diversity ◽

Statistical Similarity ◽

The Relationship ◽

Cocoa Tree

Agriculture is frequently held accountable for the depletion of biotic diversity, although a few agroforestry systems support the conservation of a number of organisms. Cocoa farming is noteworthy as an example of an agricultural activity that benefits or maintains species richness. However, the mechanism by which the biodiversity persists throughout the entire process of plant development remains obscure. In Southeastern Bahia, Brazil, cacao tree plantations support the conservation of a large amount of organisms native to the Atlantic Forest, between them the ants. This study aims at recording the relationship between cocoa tree development and ant community structure. The experiment was carried out in a series of six cocoa tree plantations aged one, three, four, eight, fifteen and 33 years, distributed across the experimental grounds of the Cocoa Research Center at Ilhéus. 1,500 ant samples were collected using the sampling techniques: hand collection, honey and sardine baits, entomological blanket and “pitfall”. Highest values for diversity and richness were reported in the 15-years-old cocoa plantation. No significant correlations between diversity, richness or plant age were reported. Considering the faunistic composition, a statistical similarity was observed between the plantations close in age to one another. Plant aging did not exert any influence on the diversity gradient and richness in the succession process of the ant community. In young plantations, there are low differences between the ants found on the ground and the ones found on the young cocoa trees. In older plantations, the ant community divides in two distinct assemblages on the ground and on the trees. The variations observed in the ant community along the plant development were likely caused by the structural organization of the dominant species mosaic.

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ROLE OF PATHOLOGICAL NEW FORMATIONS AND THEIR AGENTS IN THE FUNCTIONING OF NATURAL ECOSYSTEMS OF FOREST PARK ZONES

Forestry Engineering Journal ◽

10.34220/issn.2222-7962/2020.3/3 ◽

2020 ◽

Vol 10 (3) ◽

pp. 26-34

Author(s):

Irina Kazbanova

Keyword(s):

Natural Environment ◽

Biologically Active ◽

Tree Plantations ◽

Natural Ecosystems ◽

Forest Park ◽

Artificial Ecosystems ◽

Biological Aspects ◽

The Relationship ◽

Active Substances

In recent years, there has been great interest in pathogenic growths in plants and their pathogens. This is explained by the possibilities of their use in various environmental spheres and covers biological aspects of natural and artificial ecosystems in normal and disturbed state, as well as the assessment and forecasting of natural cycles of biologically active substances, the ability of ecosystems to self-purify, and an assessment of the positive human impact on nature. That is why, it is extremely important (for the preservation and development of the normal functioning of natural ecosystems) to find out the real significance of natural factors and development of gall formation processes in natural ecosystems, as well as the actual scale of anthropogenic impact in them. This is especially important when disturbances have reached high levels and are critical in the natural environment in forest park zones. One of the important parts of the problem is assessment of predicting the natural environment in forest park zones. Therefore, it becomes necessary to consider the relationship between tree plantations in forest park zones and pathogens of pathological neoplasms. It is also necessary to find out what there is a relationship between tree plantations and pathogens of pathological growths.

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Does available foraging area, location or colony character control the size of multispecies egret colonies?

Wildlife Research ◽

10.1071/wr95006 ◽

1998 ◽

Vol 25 (1) ◽

pp. 23 ◽

Cited By ~ 9

Author(s):

G. S. Baxter ◽

P. G. Fairweather

Keyword(s):

Colony Size ◽

Native Species ◽

New South ◽

Colonial Nesting ◽

Foraging Area ◽

South Wales ◽

Feeding Habitat ◽

Bird Colonies ◽

The Relationship

Food supply is commonly regarded as ultimately controlling the size of bird colonies. Most studies examining this problem have been on seabirds, and all in the Northern Hemisphere. To search more widely for evidence of the importance of food as a factor controlling the size of bird colonies, we investigated egret colonies in a Southern Hemisphere region. We examined the relationship between colony size and the area of potential feeding habitat around each colony, compared with variables associated with the location and the physical characteristics of each colony. All colonies (13 in total) along 800 km of coastline in New South Wales, Australia, were studied. Colony size ranged from 7 to more than 2000 nests. There were very few correlations between the number of nests and the areas of different types of feeding habitat within 20 km of colonies. However, the available area of saltmarshes proved to be a significant predictor of colony size for great (Ardea alba), intermediate (A. intermedia) and little egrets (Egretta garzetta). Saltmarshes may be stable, long-term feeding habitats for these three native ‘aquatic feeders’, but not for the terrestrially feeding cattle egret (Ardea ibis). Nest numbers of this latter species were related positively to the area of saltmarshes, and negatively to latitude, suggesting that nest numbers of this exotic species may be influenced by climate, with proximate factors such as colonial nesting with the three native species also being important. Because of the numerical dominance of cattle egrets, the numbers of nests of all species followed the same pattern as that for cattle egrets.

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The Relationship Between Food Supply, Reproductive Effort and Breeding Success in Arctic Terns Sterna paradisaea

Journal of Animal Ecology ◽

10.2307/4999 ◽

1989 ◽

Vol 58 (1) ◽

pp. 261 ◽

Cited By ~ 132

Author(s):

P. Monaghan ◽

J. D. Uttley ◽

M. D. Burns ◽

C. Thaine ◽

J. Blackwood

Keyword(s):

Breeding Success ◽

Food Supply ◽

Reproductive Effort ◽

Sterna Paradisaea ◽

The Relationship

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Maternal glucocorticoid levels during incubation predict breeding success, but not reproductive investment, in a free-ranging bird

Biology Open ◽

10.1242/bio.045898 ◽

2020 ◽

Vol 9 (10) ◽

pp. bio045898

Author(s):

Devin Fischer ◽

Robby R. Marrotte ◽

Eunice H. Chin ◽

Smolly Coulson ◽

Gary Burness

Keyword(s):

Breeding Success ◽

Positive Relationship ◽

Negative Relationship ◽

Reproductive Investment ◽

Egg Laying ◽

Maternal Survival ◽

Adaptation Hypothesis ◽

Breeding Seasons ◽

Free Ranging ◽

The Relationship

ABSTRACTThe hormone corticosterone (CORT) has been hypothesized to be linked with fitness, but the directionality of the relationship is unclear. The ‘CORT-fitness hypothesis’ proposes that high levels of CORT arise from challenging environmental conditions, resulting in lower reproductive success (a negative relationship). In contrast, the CORT-adaptation hypothesis suggests that, during energetically demanding periods, CORT will mediate physiological or behavioral changes that result in increased reproductive investment and success (a positive relationship). During two breeding seasons, we experimentally manipulated circulating CORT levels in female tree swallows (Tachycineta bicolor) prior to egg laying, and measured subsequent reproductive effort, breeding success, and maternal survival. When females were recaptured during egg incubation and again during the nestling stage, the CORT levels were similar among individuals in each treatment group, and maternal treatment had no effect on indices of fitness. By considering variation among females, we found support for the CORT-adaptation hypothesis; there was a significant positive relationship between CORT levels during incubation and hatching and fledging success. During the nestling stage CORT levels were unrelated to any measure of investment or success. Within the environmental context of our study, relationships between maternal glucocorticoid levels and indices of fitness vary across reproductive stages.

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