نتایج جستجو برای: wintering

تعداد نتایج: 2246  

Journal: :Journal of wildlife diseases 2003
David A Haukos Jim Neaville

The cloacal cestode Cloacotaenia megalops is one of the most common helminths of waterfowl. We investigated the effect of this parasite on the body condition of wintering waterfowl populations and compared prevalence among age-sex classes, over time and between habitat types on the upper Gulf Coast of Texas (USA) from October 1986-February 2000. Greater than 9,500 birds of 25 waterfowl species ...

2009
O Crowe J Wilson I Aznar SJ More

Ireland is characterised by its diversity and large abundance of wetlands, making it attractive to a wide variety of waterbirds throughout the year. This paper presents an overview of Ireland's waterbirds, including ecological factors relevant to the potential introduction, maintenance, transmission and spread of infectious agents, including the H5N1 avian influenza virus, in Ireland. Particula...

Journal: :Proceedings. Biological sciences 2004
D Ryan Norris Peter P Marra T Kurt Kyser Thomas W Sherry Laurene M Ratcliffe

Identifying the factors that control population dynamics in migratory animals has been constrained by our inability to track individuals throughout the annual cycle. Using stable carbon isotopes, we show that the reproductive success of a long-distance migratory bird is influenced by the quality of habitat located thousands of kilometres away on tropical wintering grounds. For male American red...

2011
KRISTIN RASMUSSEN JOHN CALAMBOKIDIS GRETCHEN H. STEIGER

Here, we examine the distribution, habitat use, and migratory destinations of North Pacific humpback whales wintering off Central America. Coastal boat surveys were conducted off Costa Rica and Panama between 1996 and 2003. In 1999, a broader survey was conducted along most of Central America. Over 23,000 km were surveyed, with the greatest effort off southern Costa Rica. We made 191 sightings ...

2013
Cyril Eraud Marcel Rivière Hervé Lormée James W. Fox Jean-Jacques Ducamp Jean-Marie Boutin

The identification of migration routes, wintering grounds and stopover sites are crucial issues for the understanding of the Palearctic-African bird migration system as well as for the development of relevant conservation strategies for trans-Saharan migrants. Using miniaturized light-level geolocators we report a comprehensive and detailed year round track of a granivorous trans-Saharan migran...

Journal: :Journal of insect physiology 2012
Fabio Sgolastra William P Kemp Stefano Maini Jordi Bosch

Osmia (Osmia) bees are strictly univoltine and winter as diapausing adults. In these species, the timing of adult eclosion with the onset of wintering conditions is critical, because adults exposed to long pre-wintering periods show increased lipid loss and winter mortality. Populations from warm areas fly in February-March and are exposed to longer growth seasons than populations from colder a...

2010
Denise Bewsell Margaret Brown

Dairy farming has the potential to pollute waterways through the loss of nitrogen (N), Phosphorus (P) and Faecal Indicator Organisms (FIO). Two on-farm management actions that can reduce losses of N, P and FIOs are the use of wintering feedpads, and the application of nitrification inhibitors. In this paper we outline the results of research undertaken to explore the adoption of these amongst d...

2005
Nikita Chernetsov Falk Huettmann

Bird populations are known to be affected by climate and habitat change. Here we assess on a continental scale the relationship of a bird population index for the Pied Flycatcher (Ficedula hypoleuca) with spatially explicit long-term climate data. For 1971-2001 and using multiple linear regression and AIC selection methods for candidate models we found that log-transformed 30 year long-term fal...

2010
Stephen R. Jones

Wintering raptor populations were monitored between 1983 and 1988 in a 35 km2 study area centered 8 km north-northeast of the city of Boulder, Colorado. Raptors congregated around active prairie dog (Cynomys sp.) colonies. Golden eagles (Aquila chrysaetos) , ferruginous hawks (Buteo regalis), and red-tailed hawks (Buteo jamaicensis ) were observed hunting and capturing prairie dogs. Bald eagles...

2017
Nana USHINE Tatsuo SATO Takuya KATO Shin-ichi HAYAMA

During the autumn migration of many waterfowls, body mass is lowest upon arrival at the wintering area and gradually increases during the winter. Consequently, body mass is highest before the spring migration. We studied the pattern of body mass changes in the Black-Headed Gull (Larus ridibundus) from December 2010 to December 2016 in the Shinhama area of Chiba, Japan. Based on 327 captured ani...

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