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1.
Sci Total Environ ; 854: 158660, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36089011

RESUMO

There is increasing concern about the burgeoning effects of discarded plastic on the earth's biodiversity. Quantifying the presence of plastic and other anthropogenic waste in the environment can be logistically and financially challenging, although it is possible that bird' nests can be used as bioindicators. Many birds in heavily modified terrestrial ecoystems, such as urban environments, incorporate plastic and other anthropogenic materials into their nests but our understanding of the presence of discarded plastic in nests in rural woodlands remains poor. Here, we show that plastic and other anthropogenic materials were present in 35 % of 325 pied flycatcher (Ficedula hypoleuca) nests from 17 rural woodlands throughout Great Britain, although the woodlands did vary in the amount of material incorporated into nests. Then, in an experimental test at one study site, where flycatchers were provided with a choice of two types of natural and two types of anthropogenic nest materials, they preferentially selected one natural and one anthropogenic material. In another test, the flycatchers were provided with plastic of four colours and overwhelmingly selected white and avoided orange, blue and yellow plastic. Although the flycatcher's selectivity for certain material types and colours preclude their nests being a reliable indicator of plastic in the environment, our study nonetheless demonstrates that bird species incorporate anthropogenic materials, such as plastic, into their nests in rural woodlands.


Assuntos
Aves Canoras , Animais , Ecossistema , Florestas , Biodiversidade , Reino Unido , Comportamento de Nidação
2.
Behav Processes ; 164: 59-64, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31014981

RESUMO

Nest building is a taxonomically widespread behaviour that consists of the construction of a suitable receptacle with collected materials for the incubation of eggs and sometimes for the raising of offspring. The use of specific nest materials has important fitness consequences for avian parents and offspring because they help to determine the thermal, parasitic and bacterial environment within nests and may also influence parental investment via intraspecific signalling. However, we presently know very little about the process by which nest materials are selected from the wider environment and specifically, it is unclear whether wild birds randomly or non-randomly select nest materials in relation to their local availability. Here, we report an experiment in which we provided experimental pairs of pied flycatchers (Ficedula hypoleuca) with wool, feathers and deer hair - commonly used nest materials found in their woodland habitats - close to their nests during the nest building period whilst control pairs were not provided with any materials. We found that females at experimental nests showed very clear preferences for deer hair, whilst almost completely avoiding the wool and feathers, thereby demonstrating that females exhibited very strong preferences for certain nest materials but not others. We therefore conclude that birds select nest materials in a non-random manner and do not simply use the materials most commonly available to them.


Assuntos
Comportamento de Nidação , Passeriformes , Animais , Plumas , Feminino , Cabelo ,
3.
Mar Environ Res ; 123: 38-52, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27912074

RESUMO

The macrobenthos and megabenthos responses to long-term, recurring hypoxia on the Louisiana continental shelf were compared at four locations with different historical (2000-2010) episodes of annual exposure to bottom-water hypoxia. Measurements of abundance, biomass, species diversity, and community composition of the two size classes of benthos suggested that the macrobenthic response is driven chiefly by tolerance to hypoxia, whereas the megabenthic response was affected by the ability to migrate and the availability/unavailability of macrobenthos prey at the sediment surface. The site exposed to the historically lowest average bottom-water dissolved oxygen (BWDO) concentration exhibited the lowest species diversity for macrobenthos and the highest species diversity for megabenthos, exemplifying the differential effects of hypoxia on different size classes. The high diversity and smaller average size of the megabenthos at the lowest DO site was due to high abundance of invertebrates and a preponderance of small, less vagile fishes that appeared to remain in the area after larger dominant sciaenids had presumably emigrated. The average size and the depth of habitation in the sediment of macrobenthos prey may have also influenced the abundance and biomass of megabenthos foragers.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Invertebrados/fisiologia , Água do Mar/química , Animais , Biodiversidade , Biomassa , Eutrofização , Louisiana , Oxigênio/análise
4.
Environ Sci Technol ; 47(16): 9115-23, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23931746

RESUMO

Foraminifera responded to both heavy and light oiling of marshes relative to unoiled control sites by changes to both standing stock and depth of habitation (DOH) in sediment following the 2010 Macondo well blowout. Push cores were taken from the middle marsh at sites classified as unoiled, lightly oiled, and heavily oiled based on concentrations of total polycyclic aromatic hydrocarbons ([TPAH]). Cores were sliced and stained with rose Bengal to detect live specimens of foraminifera. Short-term, sediment-mixing depths were determined using the penetration depths of excess (234)Th, and sedimentary organic carbon and carbonate were measured to distinguish depositional environments. Marsh foraminifera reacted to the highest oil concentration (5,000-18,000 ng/g of TPAH) by reducing standing stock and shortening the DOH compared with the control sites. At a second, less heavily oiled site, foraminifera responded with a shallower DOH, but with a boom in standing stock. Deformed, dead foraminifera occurred in all heavily oiled cores-but not elsewhere. Live foraminifera responded with a population boom at lightly oiled sites with [TPAH] near 1,100 ng/g. Changes in standing stock and DOH with [TPAH] suggest disturbance to the marsh food web, apparently due to oil pollution, and support the use of foraminifera as sentinel species.


Assuntos
Foraminíferos , Sedimentos Geológicos/parasitologia , Poluição por Petróleo , Louisiana , Mississippi
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