RESUMO
Conservationists often advocate for landscape approaches to wildlife management while others argue for physical separation between protected species and human communities, but direct empirical comparisons of these alternatives are scarce. We relate African lion population densities and population trends to contrasting management practices across 42 sites in 11 countries. Lion populations in fenced reserves are significantly closer to their estimated carrying capacities than unfenced populations. Whereas fenced reserves can maintain lions at 80% of their potential densities on annual management budgets of $500 km(-2) , unfenced populations require budgets in excess of $2000 km(-2) to attain half their potential densities. Lions in fenced reserves are primarily limited by density dependence, but lions in unfenced reserves are highly sensitive to human population densities in surrounding communities, and unfenced populations are frequently subjected to density-independent factors. Nearly half the unfenced lion populations may decline to near extinction over the next 20-40 years.
Assuntos
Carnívoros , Conservação dos Recursos Naturais/métodos , Leões , Densidade Demográfica , Animais , Conservação dos Recursos Naturais/economia , Gana , Humanos , Namíbia , Dinâmica Populacional , Setor Privado , África do SulRESUMO
This paper describes the development of a computerized system of temperature recording for the determination of pyrogenic substances in intravenous fluids, using the rabbit as test animal.
Assuntos
Temperatura Corporal , Pirogênios/análise , Termômetros , Animais , Computadores , Febre/induzido quimicamente , Injeções Intravenosas , Pirogênios/administração & dosagem , Pirogênios/toxicidade , CoelhosRESUMO
The keeping of animals in an enclosed area and their use for scientific work goes back to the beginning of the Christian era. This activity gradually developed into the specific science we know today. Principles of housing, animal care, equipment and management according to which, it is felt a modern animal facility should be designed, equipped and operated, are discussed.