نتایج جستجو برای: breeding periods

تعداد نتایج: 171368  

2009
Steven P. Washburn

#10 Seasonal breeding and calving is often used. Seasonal breeding and calving are not required to have a successful pasture-based dairy farm but cows bred to calve in one or possibly two compact seasons can simplify animal management. Use of two calving seasons allows more consistent year-round production of milk if that is of concern for cash flow or is a requirement for marketing milk. Poten...

Journal: :Biology letters 2015
Peter P Marra Emily B Cohen Scott R Loss Jordan E Rutter Christopher M Tonra

For vertebrates, annual cycles are organized into a series of breeding and non-breeding periods that vary in duration and location but are inextricably linked biologically. Here, we show that our understanding of the fundamental ecology of four vertebrate classes has been limited by a severe breeding season research bias and that studies of individual and population-level responses to natural a...

2004

Migratory species are of special concern in the face of global climate change, since they may be affected by changes in the wintering area, along the migration route and at the breeding grounds. Here we show that migration and breeding times of a trans-Saharan migrant, the pied flycatcher Ficedula hypoleuca, closely follow local temperatures along the migration route and at the breeding grounds...

2008
Paul G. McDonald Anahita J.N. Kazem Michael F. Clarke Jonathan Wright

Despite many studies on the evolution of cooperative breeding and helping at the nest, relatively few have explored the possibility that helping functions as a signal to gain social advantage within groups (the ‘‘pay to stay’’ and ‘‘social prestige’’ hypotheses). One of the most promising candidates for such a signaling system is the cooperatively breeding bell miner, Manorina melanophrys. Larg...

Journal: :Environmental monitoring and assessment 2009
P M Regular F Shuhood T Power W A Montevecchi G J Robertson D Ballam J F Piatt B Nakashima

To ensure energy demands for reproduction are met, it is essential that marine birds breed during periods of peak food availability. We examined associations of the breeding chronology of common murres (Uria aalge) with the timing of the inshore arrival of their primary prey, capelin (Mallotus villosus) from 1980 to 2006 across a period of pervasive change in the Northwest Atlantic ecosystem. W...

Journal: :Revista do Instituto de Medicina Tropical de Sao Paulo 2007
Lucy Nagm José Francisco Luitgards-Moura César de Souza Neucamp Fábio Saito Monteiro-de-Barros Nildimar Alves Honório Pantelis Tsouris Maria Goreti Rosa-Freitas

As for the entire Amazon Region, malaria continues to be a major health public problem in Roraima that presented an Annual Parasitic Index of 85.4 in 2005, the highest in Brazil. Information on anopheline breeding sites is an essential component in malaria control strategies. Aiming to contribute to the limited knowledge on anopheline immature forms in Roraima, collections and breeding site obs...

2017
Phoeve Macario Mauro Pichorim Paul F Doherty Guilherme S Toledo-Lima Tonny M Oliveira-Júnior Thanyria P F Câmara Shirley Macjane Melo João Lucas S Silveira Juliana C Araújo Leonardo F França

Understanding latitudinal variation in avian life-history traits has been a focus of many demographic studies around the world. However, we still know little about annual or intra-annual demographic variation within tropical regions or about how factors such as breeding season and precipitation influence demographic rates. In this study, we estimated intra-annual apparent survival of the White-...

Journal: :Proceedings. Biological sciences 2011
Brian D Todd David E Scott Joseph H K Pechmann J Whitfield Gibbons

Climate change has had a significant impact globally on the timing of ecological events such as reproduction and migration in many species. Here, we examined the phenology of reproductive migrations in 10 amphibian species at a wetland in South Carolina, USA using a 30 year dataset. We show for the first time that two autumn-breeding amphibians are breeding increasingly later in recent years, c...

2017
JOSHUA M. OSBORN

Western Tennessee is an important region for waterfowl during non-breeding periods, supporting >40% of the Mississippi Flyway population of American black ducks (Anas rubripes). Understanding habitat selection and activities of waterfowl during the non-breeding period is important for directed habitat management on national wildlife refuges and in other wetlands important in meeting regional wa...

2007
Joan Navarro Jacob González-Solís Ginés Viscor

In birds, parents adjust their feeding behaviour according to breeding duties, which ultimately may lead to seasonal adjustments in nutritional physiology and hematology over the breeding season. Although avian physiology has been widely investigated in captivity, few studies have integrated individual changes in feeding and physiological ecology throughout the breeding season in wild birds. To...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید