0000000000142031

AUTHOR

José A. Gil-delgado

Spatiotemporal patterns of dunlin (Calidris alpina) in continental lakes of the Iberian Peninsula

AbstractSpatiotemporal dynamics may present different levels of regional or local stability, generally attributed to local habitat and landscape factors, reflecting the tolerances and ecological requirements of the populations. In this study, we examined the variations of dunlin abundance and occurrence in twenty-three wetlands of the “La Mancha Húmeda” Biosphere Reserve, central Spain, between October 2010 and July 2017. In addition, we observed the variations of local abundance in the lakes of the Manjavacas lagoon complex, seeking to understand the factors that determine the local movements of the wintering individuals. Eleven lakes had records of dunlin, but most of individuals (ca. 90%…

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Invasion biology in non‐free‐living species: interactions between abiotic (climatic) and biotic (host availability) factors in geographical space in crayfish commensals (Ostracoda, Entocytheridae)

In invasion processes, both abiotic and biotic factors are considered essential, but the latter are usually disregarded when modeling the potential spread of exotic species. In the framework of set theory, interactions between biotic (B), abiotic (A), and movement-related (M) factors in the geographical space can be hypothesized with BAM diagrams and tested using ecological niche models (ENMs) to estimate A and B areas. The main aim of our survey was to evaluate the interactions between abiotic (climatic) and biotic (host availability) factors in geographical space for exotic symbionts (i.e., non-free-living species), using ENM techniques combined with a BAM framework and using exotic Entoc…

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Diet of the garden dormouse (Eliomys quercinus Linnaeus 1766) in orange groves: seasonal variation and use of available resources

Abstract The aim of this study was to describe the feeding habits of the garden dormouse Eliomys quercinus in orange groves of eastern Spain. The study area was an extensive orange grove near Sagunto (Valencia, Spain). This study combines two different non-invasive methods, the study of food store remains and the macroscopic analysis of feces. A total of 527 feces and the food remains of 172 food stores were recollected from nest boxes. Each feces was classified into five categories according to its characteristics: arthropods, gastropods, oranges, plants, and others. Throughout the year, the garden dormouse consumed all these types of food. The most consumed prey in summer and autumn were …

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Unravelling diet composition and niche segregation of colonial waterbirds in a Mediterranean wetland using stable isotopes

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Patterns of nestling provisioning by a single‐prey loader bird, Great TitParus major

Capsule Nestling provisioning rates depend on nestling age and number, and on time of season, but not on time of day. Aims To determine patterns of nestling provisioning, the effort made by the parents, and the factors which affect them. Methods Mechanical counters to determine food provisioning patterns in 229 Great Tit Parus major nests over 4 years. Results Feeding frequency per chick showed a linear increase with nestling age and total feeding frequency stabilized towards the end of the nestling period. The number of visits per nest increased linearly, while those per nestling decreased linearly with brood‐size. Feeding rates per nest declined throughout the breeding season parallel to …

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Seasonal survival in a non-hibernating Mediterranean garden dormouse population

The seasonal survival pattern of a garden dormouse Eliomys quercinus population was studied in a Mediterranean agricultural field area from East Spain, a geographical location in which this species does exhibit no hibernation. Individuals were captured from nest—boxes checked monthly during a 4-year period. Data were analysed using an open population Cormack–Jolly–Seber model including sex, age class and season as factors. Best models included the effect of age and differences in survival between adult males and females. Survival rate was more variable between seasons in males than in females or juveniles. Maximum adult male survival was reached in autumn, decreased in winter and dropped to…

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Presence of plastic particles in waterbirds faeces collected in Spanish lakes

Plastic intake by marine vertebrates has been widely reported, but information about its presence in continental waterfowl is scarce. Here we analyzed faeces of waterbirds species (European coot, Fulica atra, mallard, Anas platyrhynchos and shelduck, Tadorna tadorna) for plastic debris in five wetlands in Central Spain. We collected 89 faeces of shelduck distributed in four lakes, 43.8% of them presented plastic remnants. Sixty percent of 10 faeces of European coot and 45% of 40 faeces of mallard contained plastic debris. Plastic debris found was of two types, threads and fragments, and were identified as remnants of plastic objects used in agricultural fields surrounding the lakes. Differe…

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Prey preparation by adult Great Tits Parus major feeding nestlings

Some birds prepare food items before giving them to their nestlings. We studied the relationships between the degree of prey preparation and prey size, nestling age, brood size and time of season. We estimated the degree of preparation of 513 animal prey items, taken by using neck collars, brought to nestling Great Tits Parus major. Prey preparation increased with prey size and decreased as the nestlings grew older, as brood size increased and as the season progressed. Other factors, such as nutrient concentration (through removal of low-quality or deleterious parts) or palatability (considering scaly moth forewings unpalatable), seem also to be important in determining prey preparation. Ou…

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Geographical variation in egg size of the Great Tit Parus major: a new perspective

A recent study on geographical variation in egg size of Great Tits Parus major concluded that: (1) mean egg size tended to increase with increasing latitude; and (2) mean egg size was positively correlated with mean clutch size. Including new data on both egg and clutch size, we reanalysed the relationships between egg size, clutch size and latitude, and investigated the possible effects of habitat type, female body size and egg shape on these relationships. We found that (1) egg volume showed minimum values around 51 ° N, increasing both north and southwards; (2) female body size increased linearly with increasing latitude; (3) female body size was positively correlated with egg breadth, b…

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Populations of breeding birds in Byers Peninsula, Livingston Island, South Shetland Islands

Data about breeding populations of birds in the Antarctica are rare and fragmented. Thus, information about the status of the breeding populations of Antarctic birds is crucial given the current scenario of climate change, which is particularly acute in Antarctica. This paper presents new information about the populations of the Antarctic tern Sterna vittata, the kelp gull Larus dominicanus, the southern giant petrel Macronectes giganteus, the Antarctic skua Catharacta antarctica lonnbergi, the chinstrap penguin Pygoscelis antarctica and the gentoo penguin Pygoscelis papua on Byers Peninsula (Livingston Island, South Shetland Islands). We used line transects counts to estimate both densitie…

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Urban landscape selection by Eurasian collared dove (<i>Streptopelia decaocto</i>) in eastern Spain

The Eurasian collared dove (Streptopelia decaocto) is an invader species, and its distribution is continuously on the increase. Today its expansion has spread to the American continent. In this study we describe the effects of the urban environment on the Eurasian collared dove in eastern Spain. The abundance and presence of this dove were analyzed in 46 localities using counting points. Overall, 220-point counts were surveyed between autumn 2015 and late-winter 2016. A hierarchical partitioning analysis was used to identify explanatory variables of different types such as resources, climate and urban structure, and human presence, which may influence the presence and abundance of this spec…

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Recreational noise pollution of traditional festivals reduces the juvenile productivity of an avian urban bioindicator.

Noise is a pollutant of emergent concern for ecologists and conservation biologists. Recreational noise pollution, especially unpredictable and intermittent sounds, and its effects on wildlife and biodiversity have been poorly studied. Researchers have paid very little attention to the effect of noisy traditional festivals (fireworks and powder-guns). This study aimed to explore the effect of these recreational activities on the juvenile productivity of an urban avian bioindicator: the house sparrow. We studied five pairs of localities in the Valencia Region (E Spain) with noisy traditional festivals. Each pair was composed of one locality with festivals during the breeding season and the c…

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Differential endozoochory of aquatic invertebrates by two duck species in shallow lakes

Abstract Animal vectors are essential for the movement of invertebrate resting eggs between water bodies. However, differences in habitat preferences and feeding behaviour between bird species may result in variations in the dispersal of invertebrates via these birds, even if the different bird species live in the same lake. To test such effects, faecal samples from Anas platyrhynchos (collected in autumn and spring) and Tadorna tadorna (collected in spring) were cultured in water at 20° C and 12 L: 12 D conditions in order to quantify the resting eggs which could be internally transported by these birds. One half of each faecal sample was initially cultured at a conductivity of 0.6 mS cm −…

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Seasonal differences in drivers of species richness of waders in inland wetlands of La Mancha Húmeda Biosphere Reserve

This study forms part of the doctoral thesis of M. S. S. G., supported by a grant from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brazil. This study was jointly supported by the Ministry of Economy and Competitiveness of the Government of Spain (MINECO) and Competitiveness and the European Regional Development Fund (FEDER) ‘One way to make Europe’, through the projects: ‘CLIMAWET’ – Climate change mitigation and adaptation in the main types of Iberian Mediterranean wetlands: carbon budget and response models of species and habitats (CGL2015‐69557‐R); and ‘ECOLAKE’ – Ecological patterns in endorheic lakes: keys to their conservation (CGL2012‐38909).

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Habitat fragmentation compromises the population dynamic of the globally near-threatened Straight-billed Reedhaunter (Limnoctites rectirostris)

AbstractUnderstanding the consequences of habitat fragmentation to biological populations is crucial to develop sound conservation polices. The Straight-billed Reedhaunter (Limnoctites rectirostris) is a little known and threatened Passeriform that is highly dependent Erygo wetlands patches. Here, we evaluated the effects of habitat fragmentation on populations of the Straight-billed Reedhaunter, during the construction of a water reservoir in southern Brazil. During eight months, we monitored five Eryngo wetlands patches occupied (n=3) and no occupied (n=2) by Straight-billed Reedhaunter individuals, collecting data on their temporal occupancy patterns and registering new fragmentation eve…

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Breeding success of a colony of Boat-billed Herons Cochlearius cochlearius (Ciconiiformes: Ardeidae) in pasturelands of Costa Rica

The breeding success of a double-brooding colony of Boat-billed Herons Cochlearius cochlearius was studied in pasturelands of Costa Rica. Mean clutch size in the first clutches (2.9 eggs/nest) was higher than in second and repeat clutches (2.3 eggs/nest). Breeding success was similar in the first attempt and second attempts(20.7 % and 21.7 %, respectively). In both attempts earlier nests enjoyed a higher breeding success. Starvation of the youngest chicks within the nest and destruction of nests by bad weather conditions were the main factors related to nestling death. No effects of human activity on the reproduction of the breeding colony were observed. Rev. Biol. Trop. 54 (4): 1131-1134. …

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Laying date and clutch size of Great Tits(Parus major) in the Mediterranean region: a comparison of four habitat types

Laying data and clutch size of Great Tits were studied in four different habitats in eastern Spain: two holm oak(Quercus ilex) forests, at 500 and 900–950 m a.s.l., a zeen oak(Quercus faginea) forest, at 900–1100 m a.s.l., a pine(Pinus sylvestris) forest, at 1000–1050 m a.s.l., and orange(Citrus aurantium) plantations, at 30 m a.s.l. All sites were placed at about the same latitude (39–41°N), and all were studied during the same years (1992–95). Our results show that (1) laying date did not differ between the natural habitats at the same altitude (range of the means of yearly means 4–8 May); (2) within the same habitat type (holm oak forest) laying date was earlier at low altitude (30 April…

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Seasonal clutch size variation of multi-brooded bird species: comparisons between breeding season and latitudes

Single- and multi-brooded species of birds differ in their seasonal patterns of clutch size. Single-brooded species start with a maximum clutch size that declines continuously as the season progresses, whereas the clutch sizes of multi-brooded species usually increase to a mid-season maximum peak and then decrease progressively until the end of the breeding season. Previous studies have shown that multi-brooded migrant species present seasonal patterns that are similar to single-brooded species at high latitudes but similar to multi-brooded non-migratory species at lower latitudes. We studied the Greenfinch Carduelis chloris and Goldfinch C. carduelis populations in eastern Spain (Sagunto, …

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Position of Blackbird (Turdus Merula) Nests in Orange Trees

Nest placement affects the risk of predation and determines the microclimate for incubation. We have analysed the nest placement of the blackbird nests and the temperatures at which they are exposed in an orange plantation from Eastern Spain. The data come from a 16.9 ha of an orange plantation. In this plot, nest searching techniques were applied. Nest placement and the temperatures at midday were recorded from a sample of 84 nests. Furthermore, a sample of 16 nests was used to determine the daily variation between 8:00 and 20:00 hours. We measured the nest height, tree height, and distance from the tree centre to the nest, and the length of the longest branch. The temperatures inside the…

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Communal nesting in the garden dormouse (Eliomys quercinus)

Communal nesting has been described in many rodents including some dormouse species. In this study, we report the existence of this reproductive strategy in the garden dormouse Eliomys quercinus. Data was recorded by checking natural nests and nest-boxes from 2003 to 2013 in SE Spain. Pups and adults dormice found in nests were captured and marked. Overall, 198 nests were found: 161 (81.31%) were singular nests and 37 (18.69%) were communal nests. Communal nests were composed by different combinations of one up to three females together with one up to three different size litters. The number of communal nests varied from year to year in accordance with the number of singular nests and no se…

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Competition for nest-boxes among four vertebrate species: an experimental study in orange groves

The experiment was carried out in eastern Spain from 1986 to 1988. The nest-boxes were placed at the height where natural holes occur, visited twice a week, and cleaned after every breeding season. Four vertebrate species used the nest-boxes: great tit Parus major, house sparrow Passer domesticus, tree sparrow Passer montanus, and black rat Rattus rattus. The first species to occupy the nest-boxes, the great tit, was the least able to defend them. During the third year breeding by the great tit in the nest-boxes decreased markedly, probably due to the increase of house sparrow and black rat occupation. We suggest that differences among species in their ability to discover and use new holes …

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Aspects of the breeding ecology of Rufous Bush RobinsCercotrichas galactotesin southeast Spain

The breeding ecology of Rufous Bush Robin Cercotrichas galactotes was studied over 4 years in southeast Spain. The vegetation of the study area was made up mainly of Olives, Almonds and small shrubs. The density of this species decreased from 0.36 pairs 10 ha-1 in 1980 to 0.7 pairs 10 ha-1 in 1984, a decrease similar to one observed in other parts of Spain. The breeding season lasted from late May or early June to late August. About two-thirds of the pairs laid 2 clutches. Mean clutch size was 3.6 eggs. The incubation period lasted about 13 days and nestlings left the nest after 10 days. Mortality was greater in first clutches, mainly because of predation, which did not occur in second clut…

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