نتایج جستجو برای: population dynamics

تعداد نتایج: 1090949  

2017
Jeffrey F. Bromaghin Ryan M. Nielson Jeffrey J. Hard JEFFREY F. BROMAGHIN RYAN M. NIELSON

Concern regarding the potential for selective fisheries to degrade desirable characteristics of exploited fish populations is growing worldwide. Although the occurrence of fishery-induced evolution in a wild population has not been irrefutably documented, considerable theoretical and empirical evidence for that possibility exists. Environmental conditions influence survival and growth in many s...

2001
Grace Chan

In the past, ecologists have been debating about the relative importance of density-dependent versus density-independent factors in determining population dynamics. Between 1989 and 1992, an experiment was conducted at the University of Reading for studying how both densityindependent and density-dependent factors affect greenbottle blowfly population dynamic structure. See Daniels (1994). Taki...

2000
Reginald H. Barrett BARRY R. NOON

Population models have great potential as management tools, as they use information about the life history of a species to summarize estimates of fecundity and survival into a description of population change. Models provide a framework for projecting future populations, determining the effects of management decisions on future population dynamics, evaluating extinction probabilities, and addre...

2003
KENNETH B. ARMITAGE

Rates of amicable and agonistic behaviour are not correlated either within or between two colonies of Marmota flaviventris nor is there any consistent pattern of rates being higher in one colony than in the other . Rates of social behaviour are related to population density, the age-sex structure of the population, the individual behavioural characteristics of the residents and potential recrui...

2012
Venyton N. L. Izidoro Leandro N. de Castro Angelo C. Loula Charbel N. El-Hani

Calangos is an under development educational game based on the fauna and flora of the desert-like field of the sand dunes in the middle São Francisco River, located within the Caatinga biome in Brazil. One of the player’s goals is to manage the behavior of species of lizards that inhabit this biome, with consequences to their ecology and evolution. For the development of the game, a prototype, ...

2006
Mary Beth Decker

of Proposed Work (250 words or less): The Bering Sea shelf has experienced significant climatic changes over the past 30 years. During this period of intense physical variation, dramatic and unexpected changes have taken place in the southeastern Bering Sea ecosystem, including large fluctuations in jellyfish biomass. To explore to effects of climate change on jellyfish populations, we will use...

2006
S. P. Rushton D.J.A. Wood P.W.W. Lurz J. L. Koprowski

The Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis; MGRS) is among the most critically endangered mammals in the United States and is isolated on the periphery of the species’ range, potentially increasing its conservation priority. To investigate potential threats to the population and provide a tool for land managers, we developed a spatially explicit population dynamics model. ...

2012
Lori M. Hunter

RAND is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND ® is a registered trademark. RAND's publications do not necessarily reflect the opinions or policies of its research sponsors. All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or informat...

2006
L. PERSSON A. BERTOLO A. M. DE ROOS

The population total length (LT) structures and individual growth trajectories for three stream living pike Esox lucius populations were studied for 7 years. All three populations exhibited small variation in both population LT structure and individual growth trajectories over time. These dynamics contrasted to the much more variable population LT structure of perch Perca fluviatilis studied pr...

2010
Winfried Lampert

Many cyclopoid copepods change their feeding habits during development. Young stages are herbivorous, whereas adults are carnivores or omnivores. A demographic model based on physiological parameters is developed to study the effect of cannibalism on the population dynamics of cyclopoids and their prey. If alternative prey are available and their potential growth rate is higher than the potenti...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید