Densities of individually marked migrants away from the marking site to estimate population sizes : a test with three wader populations

Capsule Population estimates based on the mark–resighting method can be a useful alternative to population-wide counts.

Aims To investigate whether the mark–resighting method can be used as an alternative to counts to estimate the size of wader populations.

Methods Individual colour-marking and subsequent resightings allowed accurate estimates of annual survival for three populations of waders, on which basis we could estimate the actual number of marked birds alive. Densities of marked birds were determined on sites away (2000–4300 km) from the ringing locations expecting marked birds to be randomly distributed among non-marked conspecifics. Population sizes are estimated by combining these densities with the number of marked birds alive.

Results We found indications that the distribution of marked birds was indeed random in the locations away from the site of marking. The estimated population size of Red Knot Calidris canutus canutus was in accordance with the most recent estimates based on counts. Our estimate of the Calidris c. islandica population was somewhat lower, and that of the Bar-tailed Godwit Limosa lapponica taymyrensis population was considerably lower than the latest estimates based on counts.

Conclusion Population estimates based on the mark–resighting method can be a useful alternative for, or addition to, population-wide counts, as long as the assumption of random distribution of marked birds at the reading sites is taken into account. We conclude that the Afro-Siberian Bar-tailed Godwit population has recently decreased in size or has been substantially overestimated during the counts.

The execution of Van Nguyen: an Australian perspective

The execution of 25-year-old Melbourne man, Van Nguyen, by Singaporean authorities on 2 December 2005 for attempting to smuggle 400 grams of heroin out of Singapore was cruel. It was also futile. Yet, there are three important lessons that can be learned from his killing. The first lesson is that if Australia is to exert genuine moral pressure on nations to abolish the death penalty it must do so in a principled manner, rather than making expedient pleas when Australians happen to be on the wrong end of the cruel practice. Secondly, sentencing practice in Australia, while not condoning capital punishment, is unjustifiably punitive and we should ameliorate the harshness of some of our sentencing laws. Finally, the death of Nguyen, while tragic, was no more tragic than the millions of other preventable deaths that occur daily throughout the world. The compassion displayed toward Nguyen should be used as a catalyst for enlarging our sympathy gland in relation to all preventable deaths. I now discuss these in further detail.

Defuturing an architecture of destruction: a reconciliation of Van Berkel and Bos to the new design philosophy of Tony Fry

For some time now Tony Fry has promoted the idea of 'The Sustainment', an idea that asserts a paradigm shift in attitudes to consumption. 'The Sustainment' recognises that increasingly human futures are products of self-determination and not chance. Fry’s hypothesis can be understood through his concept of Defuturing, a philosophy that questions the role of design and the responsibility of designers to facilitating the ability to sustain (Fry 1999).
Central to Fry’s philosophy is an awareness that it is in the best interests of designers and their clients, as inhabitants of cultures increasingly driven by technology, to be aware of the relationships between the products and theories of design and the processes and implications of technological change. This is an awareness that is central to the concepts, work, and methodologies of the ‘UN Studio’ of Van Berkel and Bos described and elaborated upon in Move – Imagination, Techniques, and Effects (Van Berkel & Bos 1999). Here, Ben Van Berkel defines the parameters and methodologies employed by UN Studio in an environment of technological and socio-economic change. The Dutch practice could be said to exemplify something of a zeitgeist in current architectural design that sees architects, as Van Berkel and Bos view them, as “fashion designers of the future, dressing events to come and holding up a mirror to the world (Van Berkel & Bos 1999, back cover).” It is a zeitgeist that Fry might see as aligned to the resilient hype of ‘new creativity’, ‘globalisation’ the ‘romance with technology’, and the vacuous-ness of the world of fashion. (Fry The Voice of Sustainment: on Design Intelligence 2005).
A source of breaking down such design propaganda is identified by Fry in the notion of ‘scenarios,’ which “provide a mechanism for politico-practice assemblage in which dialogues and narratives of change can be rehearsed in ways that enable participants to re-educate themselves via critical confrontations” (Fry The Voice of Sustainment: on Design Intelligence 2005). From such a perspective this paper aims to practically illustrate and ground the Defuturing of Fry by establishing a dialogue between his writings and the theories that have generated the architectural designs of Van Berkel and Bos and there UN Studio. This will be a ‘scenario’ that examines therefore an appropriation and transformation of the applied intellectual practice of Van Berkel and Bos. Through this confrontation we shall explore the question of why sustainability appears to be so low in the agenda of many pre-eminent contemporary architects, and how we might refocus therefore practice and theory on the ability to sustain.

Artikel 3(1) en (2) van die Mineral and Petroleum Resources Development Act 28 van 2002: 'n herbeskouing

Sections 3(1) and 3(2) of the Mineral and Petroleum Resources Development Act 28 of 2002
This contribution entails a discussion of the impact of section 3 of the Mineral and Petroleum Resources Development Act on various aspects of the new mineral and petroleum law. At the core of the discussion is the question of how this section is interpreted by various commentators, and the implications of the different opinions on the application of the section. The initial discussion highlights problems with the new definition of a "mineral": Soil, including topsoil is at present included in die definition of a "mineral" in the act. The definition should be rectified by the legislature as it has far-reaching consequences in respect of the extent of the state's power in terms of section 3(2) of the act to grant entitlements in respect of minerals, including topsoil. The implications of section 3 for the control and management of minerals are discussed and placed in the context of the question about the constitutionality of the act. It is argued that legislative guidance is urgently needed to clarify continuing uncertainty, caused by sloppy drafting and different opinions about the connection between private law and public law in relation to minerals and the actual position of existing right holders.

God, gratuitous evil, and van Inwagen's attempt to reconcile the two

Both critics and advocates of evidential arguments from evil often assume that theistic belief is not compatible with gratuitous evil. It is often assumed, in other words, that an omniscient, omnipotent, perfectly good being would not permit an evil unless he had a morally sufcient reason to permit it. However, this cornerstone of evidential arguments from evil has come under increasing re of late, in particular by Peter van Inwagen. The aim of this paper is to outline and then assess van Inwagen's attempt to reconcile theism with gratuitous evil.

L. Bernard Hall and the feminine in Australian painting 1885-1935

This thesis draws on images to explore the processes by which an individual - Lindsay Bernard Hall - and a categorical concept - the feminine - became devalued in Australia's national tradition. It celebrates Hall's contribution to Australia's cultural heritage and the significance of his art in the visual record of modernising womanhood.

Do Red Knots (Calidris Canutus Islandica) routinely skip Iceland during southward migration?

Subspecies Calidris canutus islandica of the Red Knot breeds on the arctic tundra of northeastern Canada and northern Greenland and winters along the coasts of northwestern Europe. During northward migration, it stops over in either Iceland or northern Norway. It has been assumed that it does the same during southward migration. Using ratios of stable carbon isotopes (δ ¹³ C) in whole blood, blood cells, and plasma, we investigated evidence for a stopover in Iceland en route from the breeding grounds to the Dutch Wadden Sea. With the expected diet (shellfish) and stopover duration at Iceland (12-15 days, maximum 17 days) and the turnover rates of blood cells (15.1 days) and plasma (6.0 days), Red Knots that stopped in Iceland should arrive with a blood (cell) δ ¹³ C midway between a tundra (-24.7[per thousand]) and a marine value (-14.0[per thousand]) and a plasma δ¹³ C approaching the marine value (-15.3[per thousand]). However, many adults arriving at the Wadden Sea had δ¹³ C ratios in blood (cells) and plasma below these levels, and some arrived with clear tundra signals in blood cells, suggesting that they skipped Iceland during southward migration. Surprisingly, available data suggest this also to be true for juveniles during their first southward migration. The δ ¹³ C signature of second-year birds confirmed that they oversummered in the Wadden Sea. Our findings contradict the largely untested idea that juvenile shorebirds make more stopovers than adults as well as the idea that the migration between the Nearctic and Europe is necessarily a two-leg process.