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Context. Large reserves have potential to provide important refugia for fragmentation-sensitive species as they lack many aspects of habitat degradation associated with fragmented regions. However, large reserves often have a history of deleterious management practices that may affect the restoration of biological diversity. One significant symptom of habitat fragmentation and disturbance in Australia is the increased occurrence of the aggressive noisy miner (Manorina melanocephala). In Queensland, however, even large continuous areas of woodland appear to be dominated by the noisy miner.
Aims.We examined the severity of this phenomenon by identifying the interactions between habitat structure, noisy miner abundance and avian assemblages in a private and a public conservation reserve in central Queensland. We investigated potential constraints on restoration of avian diversity including: (1) how changes in habitat structure as a result of grazing by feral animals and burning regimes affect bird assemblages; and (2) how the noisy miner impacts on avian assemblages in these unfragmented woodlands.
Methods. Bird surveys and habitat assessments were conducted in 49 sites on three separate occasions. Fire history and intensity of grazing pressure were determined for each site with direct and indirect observations. Sampling for lerp from insects of the family Psyllidae was also undertaken during the survey periods. A Bayesian model averaging (BMA) approach was used to model avian response to each of the habitat variables.
Key results. The noisy miner dominated most of the study area, reducing small passerine abundance and species richness. Noisy miners were advantaged where shrub cover was low and feral grazing impacts were evident. Disturbance factors including recent wildfire and heavy grazing strongly reduced small passerine bird richness and abundance.
Conclusions. Reducing the abundance of this 'reverse keystone' species requires control of feral herbivore populations and modification of fire regimes to achieve a mosaic including patches with a dense shrub layer.
Implications. Deleterious interactions with competitive native species, such as noisy miners, are obstacles to bird conservation not only in fragmented landscapes but also in large, continuous woodland areas. Land mangers of protected areas need to be aware of shifts in interactions among native species driven by habitat disturbance, which may ultimately affect conservation outcomes.

'Tactical voting' refers to voting contrary to one's nominal preferences. The usual form of tactical voting described in the literature consists of 'third' party supporters in plurality electoral settings voting for one of the two major parties in their constituency. This Note aims to demonstrate both theoretically and empirically the existence of the converse phenomenon, i.e. followers of one of the two big parties voting for a small one. We shall call this phenomenon 'inverse tactical voting' (ITV).

International audience ; —In the future battlefields, communication between commanders and soldiers will be a decisive factor to complete an assigned mission. In such military tactical scenarios, network topology is constrained by the dynamics of dismounted soldiers in the battlefield. In the battlefield area, soldiers may be divided into a number of squads and fire teams with each one having its own mission, especially in some critical situation (e.g., a military response to an enemy attack or a sweep operation of houses). This situation may cause an unpredictable behavior in terms of wireless network topology state, thus increasing the susceptibility of network topology to decomposition in multiple components. This paper presents a Group Mobility Model simulating realistic battlefield behaviors and movement techniques. We also analyze wireless communication between dismounted soldiers and their squad leader deployed in a mobile ad hoc network (MANET) under different packet sending rate and perturbation factor modeled as a standard deviation parameter which may affect soldiers' mobility. A discussion of results follows, using several performance metrics according to network behavior (such as throughput, relaying rate of unrelated packets and path length).

AbstractRussia and the US have significantly reduced their tactical nuclear weapons over the past twenty years. The remaining weapons have been moved from active service and stored separate from their delivery systems. However, both still keep tactical nuclear weapons available for eventual deployment, and Moscow maintains not only a larger but also a much more diverse stockpile of such weapons than the US. The prospects for designing an arms control regime covering TNW are complicated by a series of factors. Technically, verifying any limitations or reductions of non-deployed weapons is an extremely sensitive and challenging task as it would require opening nuclear depots for inspection. Politically, the two countries differ in the assessment of a future role of nuclear arms. While the US anticipates that further development of its advanced conventional capabilities would lead to diminishing the role of nuclear weapons, it is exactly the weakness of its conventional forces which causes the Russian defence establishment to project a growing role for nuclear weapons. These two distinct trajectories largely explain the differences in the two countries' approaches to the TNW arms control and make any agreement less likely to materialize any time soon. They also explain why Moscow has become increasingly sceptical with regard to including TNW within an arms control regime.

"15 July 1992." ; Shipping list no.: 92-0536-P. ; "Supersedes TB 43-0002-81, dated 16 November 1983." ; Mode of access: Internet. ; 2