Tormod V. Burkey

• PhD
• Researcher at University of Oslo

To study the effect of habitat fragmentation on population viability, I used extinction rates on islands in archipelagoes and estimated the relative probability of extinction per species on single large islands and sets of smaller islands with the same total area. Data on lizards, birds, and mammals on oceanic islands and mammals on mountaintops an...

A stochastic simulation model of extinction in nature reserves is presented. The model yields clear guidelines for minimizing the probability of stochastic extinction in reserves. Simulation time is crucial to how the risk of extinction changes with fragmentation. For short to moderate time spans the probability of extinction increases exponentiall...

Extinction rates have risen to perhaps 104 the background rate. Much of this increase is due to projected influences of habitat loss on regions of the world with tropical moist forest. This ecosystem, home to a disproportionate amount of global biodiversity and a major regulator of regional and global climate, also faces disproportionately severe t...

Depredation of seeds and eggs in a Belizian rainforest was investigated using peanuts and hen's eggs. Seed predation rates were significantly higher 500 m into the forest from the edge than 30 m and 100 m from the edge. Conversely, egg predation was higher in a 100 m zone near the edge. These edge effects were evident even though the edge was a min...

Extinction is notoriously difficult to study because of the long timescales involved and the difficulty in ascertaining that extinction has actually occurred. The effect of habitat subdivision, or fragmentation, on extinction risk is even harder to study, as it requires copious replication of habitat patches on large spatial scales and control of a...

Why are we not acting to save the world? A lot of people say humans won’t act until we physically feel the repercussions ourselves, but by then it will be too late. “Saving the world” is just a shorthand for fixing problems with international dimension and that involve ecological tipping points. Our culture is not used to dealing with issues where...

http://www.spartacus.no/index.php?ID=Bok&ID2=706 https://itunes.apple.com/us/book/hvem-er-villest-i-landet-her/id888747624

Schemes that aim to prioritize species based on their conservation value

blundell burkey table.

Biodiversity offsets are conservation projects used mainly by business to counterbalance the environmental impacts of their operations, with the aim of achieving a net neutral or even beneficial outcome for biodiversity. Companies considering offsets need to know: (1) if there are areas of such biological importance that no impact is acceptable, an...

Across the globe, much current research reflects concerns over the effect of habitat fragmentation on the viability of species and populations. This is an immediate and important concern for the Kingdom of Thailand, where decisions about land use are at a critical juncture. Thailand is in danger of losing species that play a special role in Thai cu...

Habitat loss, the reduction of the habitat area available, is known to greatly reduce resident species' expected time to extinction. This process is widely recognized, if not adequately understood or quantified except in very simple models. However, it is not well understood how the time to extinction will change if the remaining habitat is distrib...

Landscapes in the Mediterranean basin have been modified by human exploitation for ages. Currently, European Community (EC) agricultural policies are reshaping land use patterns and vegetation disturbance regimes. It is uncertain how vegetation and animal population dynamics will be modified by the novel spatial patterns of habitat fragmentation an...

1. Density-independent weather effects can have important consequences for the demography of terrestrial herbivores because precipitation, temperature and insolation influence plant phenology, forage quality and biomass production, which in turn affects the habitat carrying capacity. Since forage digestibility influences intake and weight gain, lif...

PhD Thesis, Princeton University 1995.

Soulé et al. (Biol. Conserv., 1979, 15, 259-72) predicted that without intensive management, East African game reserves would lose a large proportion of their large mammal faunas if they became completely insularized (isolated from other habitat areas with healthy wildlife populations). They based their predictions on the loss of large mammal speci...

Ordered categorical (or semi-quantitative) data are frequently encountered in ecology (e.g., Steen et al. 1990; Ménard et al. 1993). Researchers often resort to semi-quantitative measures (to describe abundance patterns, age or stage structures, environmental factors, etc.) to reduce processing time and/or because of financial constraints, while re...

Part I: Analysis and methodology. Can ecological theory cross the land-sea interface? A modern view of applied time series analysis The great ocean conveyer Integration of spatial analysis in long-term ecological studies A general review of dynamical systems Analysis of long-time series Part II: Comparisons of scales. Physical and biological scales...

To test the premises and predictions of the Janzen-Connell model (Janzen's spacing mechanism), seeds of the rainforest canopy tree, Brosimum alicastrum, were placed at different distances from the parent tree and their removal observed over 3 weeks. The number and density of naturally occurring seeds at different distances from the parent tree were...

We present a seasonal model of a population in which there are differences between individuals. Dominant individuals defend breeding/feeding territories and are always assumed to obtain sufficient resources during the summer; in the winter there is no breeding, no territorial defence, and no individual differences. During the summer there is contes...

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This paper reviews the basic principles that anyone working on projects that affect natural habitats must take into consideration — kind of "everything you need to know about ecology but were afraid to ask". It is also a quick guide to people concerned about the environment, covering the mechanisms we have to worry about which human activity may be...