Asymmetrical Resource Ownership Increases Owners’ and Reduces Non‐Owners’ Motivation to Fight in the Mangrove Rivulus,Kryptolebias marmoratus

Resource ownership often increases an individual's aggressiveness and its probability of defeating a competitor. Individuals contesting resource owners could therefore incur higher costs, making individuals reluctant to compete with owners. We tested the hypothesis that animals use asymmetry in resource ownership as a cue for contest costs and adjust contest decisions accordingly. Using a mangrove rivulus fish (Kryptolebias marmoratus), we staged (1) contests with a randomly assigned asymmetry in resource ownership (one fish was provided with a shelter) and (2) contests in which neither fish had a shelter. Owners that were in their shelters at the contest start showed a greater tendency to fight and won more contests than their intruder opponents; those outside the shelter at the start did not. Compared with fish in contests with no shelters at stake, shelter owners had a higher tendency to fight whether or not they were in their shelters at the start; intruders, however, had a lower tendency to fight only against owners that were inside the shelter at the start. These results demonstrate (1) that ownership status influences both owners’ and intruders’ contest decisions (and in opposite directions), producing a detectable ownership advantage and (2) that intruders required confirmation of their opponents’ ownership status before retreating without challenging them. Ownership status per se is therefore important to the fish's contest decisions.     

Assessing the status of British wild brown trout, Salmo trutta, stocks: a pilot study utilizing data from game fisheries

SUMMARY. 1. This paper describes an analysis of results from a questionnaire (Giles, 1987) which requested information on the status of game fish stocks (especially wild brown trout Salmo trutta L.) from those Game Conservancy members who own or manage fisheries. Also included are data arising from fishery log book records which are used to indicate trends in brown trout catch per unit effort (CPUE) over past decades.
2. The key finding from questionnaire returns was the widespread reporting of apparent declines of wild brown trout stocks in a total of twenty-seven sites throughout Britain. The affected waters are geographically widespread from the south-west of England through southern and south-east England, south Wales, northern England and Scotland including the Western Isles. Suspected stock declines of migratory (sea) trout, salmon Salmo salar L. and grayling Thymallus thymallus L. were also reported. Where brown trout occur alone, a significantly higher proportion of questionnaire returns recorded a stock decline compared with fisheries containing both brown and rainbow trout Salmo gairdneri Richardson.
3. Trout catch records from a small selection of differing fishery types are presented and the value of such data in fish stock assessment is discussed.     

Public Health Ethics and a Status for Pets as Person-Things

Within the field of medical ethics, discussions related to public health have mainly concentrated on issues that are closely tied to research and practice involving technologies and professional services, including vaccination, screening, and insurance coverage. Broader determinants of population health have received less attention, although this situation is rapidly changing. Against this backdrop, our specific contribution to the literature on ethics and law vis-à-vis promoting population health is to open up the ubiquitous presence of pets within cities and towns for further discussion. An expanding body of research suggests that pet animals are deeply relevant to people’s health (negatively and positively). Pet bylaws adopted by town and city councils have largely escaped notice, yet they are meaningful to consider in relation to everyday practices, social norms, and cultural values, and thus in relation to population health. Nevertheless, not least because they pivot on defining pets as private property belonging to individual people, pet bylaws raise emotionally charged ethical issues that have yet to be tackled in any of the health research on pet ownership. The literature in moral philosophy on animals is vast, and we do not claim to advance this field here. Rather, we pragmatically seek to reconcile philosophical objections to pet ownership with both animal welfare and public health. In doing so, we foreground theorizations of personhood and property from sociocultural anthropology.     

Legal Rights in Human Bodies, Body Parts and Tissue

This paper outlines the current common law principles that protect people’s interests in their bodies, excised body parts and tissue without conferring the rights of full legal ownership. It does not include the recent statutory amendments in jurisdictions such as New South Wales and the United Kingdom. It argues that at common law, people do not own their own bodies or excised bodily material. People can authorise the removal of their bodily material and its use, either during life or after their death, for medical or scientific purposes. Researchers who acquire human bodies, body parts or tissue pursuant to such an authority have a right to possess and use them according to the authorisation they have been given, but their rights fall short of full ownership because they are limited in the way that they can use the material. The legal rights of researchers who develop intellectual property and biological products from excised human tissue can be adequately protected by existing common law principles without the need for a new legal principle that people own body parts and tissue removed from their bodies.

Economic and political differentiation among Galole Orma women*

The Orma are cattle‐herders living close to Tana River in Kenya. This paper gives an outline of Orma propertyholding and of women's contributions to production in terms of labor. The relationship between control over resources (either outright ownership, rights over use, or indirect control through children's ownership) is discussed in relation to the influence women wield in issues considering sale of stock, decisions to shift or not, and the use of child labor. Formal and informal positions of power held by Orma women are analysed in relation to the effectiveness of women's influence over production decisions. The access that Orma women have to property varies with the degree of integration into the cash economy and to one's position on the nomadic‐sedentary continuum. With greater sedentarization and integration into cash economy women seem to lose control over economic resources in terms of outright ownership. They participate less in manual tasks of production. However, by a variety of informal and formal means, they gain more control over economic decision‐making.     

The adaptation of biological membranes to temperature and pressure: Fish from the deep and cold

The homoeostatic regulation of bilayer order is a property of functional importance. Arguably, it is best studied in those organisms which experience and must overcome disturbances in bilayer order which may be imposed by variations in temperature of hydrostatic pressure. This article reviews our recent work on the adaptations of order in brain membranes of those fish which acclimate to seasonal changes in temperature or which have evolved in extreme thermal or abyssal habitats. The effects of temperature and pressure upon hydrocarbon order and phase state are reviewed to indicate the magnitude of the disturbances experienced by animals in their environments over the seasonal or evolutionary timescale. Acclimation of fish to altered temperature leads to a partial correction of order, while comparison of fish from extreme cold environments with those from temperate or tropical waters reveals a more complete adaptation. Fish from the deep sea also display adaptations of bilayer order which largely overcome the ordering effects of pressure.     

Exploited marine invertebrates: genetics and fisheries

The application of genetic techniques to invertebrate fisheries is in many ways essentially similar to that in vertebrate (i.e. finfish) fisheries, for which there is already an extensive body of published data. However, there are also relative differences which lead to particular problems in the use of genetic data to study commercially important invertebrate species. The main role for genetics of both vertebrates and invertebrates has been, and is likely to continue to be, the identification of groups of interbreeding individuals as the basis for a fishery. It is in the identification of the breeding unit that the genetic differences between vertebrates and invertebrates can be of practical significance. The genetic breeding unit, usually called a 'stock' in fisheries biology, generally shows a certain uniformity of size in most marine fish which have been studied. Smaller or less mobile fish (e.g. flatfish) may only range a few tens of kilometres to their breeding grounds, whilst in more mobile, particularly migratory pelagic species (e.g. Scombridae), the area occupied by a stock is likely to be far greater and for a few (e.g. large pelagic elasmobranchs), a single unit of stock may be almost circumglobal. However, marine fish generally, particularly those large or plentiful enough to be of commercial interest, are likely to be fairly mobile and in many cases the order of mobility is likely to be in the region we might predict from our knowledge of the biology and habits of the species. In the genetic assessment of `stocks' for invertebrate fisheries, we face a number of additional problems, mostly related to the large evolutionary range of invertebrates exploited and their widely different biology. Although in Europe and North America marine invertebrate fisheries may be thought of as being mainly for decapod crustaceans and bivalve molluscs, globally commercially important marine invertebrate fisheries range from sponges to squid and include such diverse groups as sea cucumbers, barnacles, krill, octopuses, cuttlefish, sea anemones, ascidians, polychaetes, sea urchins, gastropods and jellyfish. An obvious feature of many of these invertebrates is that the adult (i.e. commercial) stage of the life cycle is sessile (e.g. barnacles, sponges, ascidians) or of very limited mobility (e.g. sea anemones, sea urchins, bivalves, gastropods), with the result that the dispersive phase of the life cycle is the larva. Other groups (e.g. krill, jellyfish) are planktonic or nektonic and may cover very large distances, but, unlike fish, have little control over the distance or direction of travel, whilst some of the open ocean pelagic squid are more mobile than most fish and may migrate thousands or kilometres to spawning grounds. The very low mobility of both larva and adult in some invertebrates indicates that dispersal, and hence stock size, is likely to be low and that, therefore, stocks are far more vulnerable to overfishing than in most fish species. An additional difficulty is that genetic studies to date indicate a remarkably high incidence of cryptic speciation in marine invertebrates, sometimes even in comparatively well studied commercially important species. Thus, although to date marine invertebrate fisheries have not received the same level of attention from geneticist as finfish fisheries, it is clear that for invertebrate fisheries genetic data are relatively far more important if a fishery is to be exploited without being endangered.     

Widespread primary,but geographically restricted secondary,human introductions of wall lizards,Podarcis muralis

Establishing the introduction pathways of alien species is a fundamental task in invasion biology. The common wall lizard, Podarcis muralis, has been widely introduced outside of its native range in both Europe and North America, primarily through escaped pets or deliberate release of animals from captive or wild populations. Here, we use Bayesian clustering, approximate Bayesian computation (ABC) methods and network analyses to reconstruct the origin and colonization history of 23 non‐native populations of wall lizards in England. Our analyses show that established populations in southern England originate from at least nine separate sources of animals from native populations in France and Italy. Secondary introductions from previously established non‐native populations were supported for eleven (47%) populations. In contrast to the primary introductions, secondary introductions were highly restricted geographically and appear to have occurred within a limited time frame rather than being increasingly common. Together, these data suggest that extant wall lizard populations in England are the result of isolated accidental and deliberate releases of imported animals since the 1970s, with only local translocation of animals from established non‐native populations. Given that populations introduced as recently as 25 years ago show evidence of having adapted to cool climate, discouraging further translocations may be important to prevent more extensive establishment on the south coast of England.     

Physiological seawater adaptation in juvenile Atlantic salmon (Salmo salar) autumn migrants

Summary

• 1 About 25 % of juvenile Atlantic salmon (Salmo salar) migrating downstream in the River Frome in southern England do so in the autumn rather than in the spring. Here, we examine the physiological status of these fish with regard to those features that adapt them to sea water during the parr–smolt transformation (i.e. gill Na⁺K⁺ ATPase activity; the number, size and type of chloride cells on the gill lamellae; salinity tolerance and relative plasma thyroid levels).
• 2 Autumn migrants, and those fish which subsequently reside in the tidal reaches during the winter, are not sufficiently physiologically adapted to permit permanent or early, entry into the marine environment.
• 3 It is not known what proportion of autumn migrating fish survive and return to spawn as adults. If significant numbers do return, however, the production from tidal reach habitats must be taken into account in the development of salmon stock management strategies, especially monitoring and assessment programmes, and in the evaluation of factors affecting stocks.

     

Western anthropological concepts in stateless societies: A retrospective and introspective look at the Dagaaba

Conclusion Anthropological legal concepts of the so-called primitive societies originally induced by prevailing Western philosophical ideas, political thought and jurisprudence require a serious review. The current emphasis by scholars in the anthropology of law on dispute processes in Africa is fulfilling an important need. Given the constantly transforming and unstable nature of modern African political systems, a clearer understanding of native concepts and fundamental value systems is essential. For instance, concepts such as ownership, property rights in land, legal obligation, individual or collective rights must be thoroughly understood within the framework of history and state transformation to be able to help to mediate and settle major inter and intra ethnic disputes in such areas as land tenure, marriage and succession.It is apparent that among the Dagaaba, the obligation to obey the law of the modern state is seriously complicated by the existing native concept of legal obligation which requires the evaluation of laws. To the extent that coercive sanctions are imposed, obedience may be achieved, but the values embodied in the laws may not be internalized. Thus, the laws of the modern state may simply constitute ordar (plural of ordir), that is, coercive commands with no necessary utility or rationality behind them. Such ordar would then not constitute a solid enough basis for dispute resolution when the modern legal system falters in a political crisis.The importance of continuing legal research in fundamental normative systems, concepts and values of tradition society can be seen from our discussion of legal obligation and the mental requirements for culpable conduct among the Dagaaba. These concepts help explain not only some of the institutional structures of the Dagaaba, but also the Dagaaba vision of their own native reality and the legal choices made. Without such studies, one would have only a partial view of African societies. Such research should employ original language techniques such that the full implications of concepts such as collective rights, individuality, and similar group-based legal rights and duties can be properly analyzed. With particular reference to the Dagaaba, further research should address the full implications of the yir, yiiluu and balu in terms of ownership, use of or access to property, and succession to various types of property. It should also examine the effects of customary, statutory and Christian marriage on the group concepts and the implications for succession to property. Since the Dagaaba appear to have been a male dominated society, it will be important in future work to focus attention on women's rights within the framework of these groups. Finally, to explore more fully the concept of balu and its legal implications fieldwork should include the Dagaaba in Burkina Fasso, where the concept appears to have been developed more functionally.Kojo Yelpaala is Professor of Law at the McGeorge School of Law, University of the Pacific, Sacramento, California.     

Variation in some biological characteristics of British sea trout, Salmo trutta L.

Almost 50 assessments of British sea trout are available in the literature and the objective in this work is to examine variation in the parameters by which the fish are usually described and to discover biological criteria on which stocks may be classified. Eight statistics are common to the majority of stock evaluations: mean smolt age, proportion of finnock to spawn, mean age of a stock at first maturation, size achieved by the smolt at migration, rate of growth at sea, survival at sea, diversity of age categories in a stock and condition factor of sea-run fish. When the influence of each factor on the others is tested two characteristics emerge as being of key importance in the biology of adult sea-trout; the life expectancy and the weight: percentage previous spawners in a sample. The distribution of stocks is discussed in this context and two main groupings of British sea trout, corresponding geographically with the Irish sea and the Atlantic sea-board, are proposed.     

Genetic stock identification of Atlantic salmon (Salmo salar) populations in the southern part of the European range

Background

Anadromous migratory fish species such as Atlantic salmon (Salmo salar) have significant economic, cultural and ecological importance, but present a complex case for management and conservation due to the range of their migration. Atlantic salmon exist in rivers across the North Atlantic, returning to their river of birth with a high degree of accuracy; however, despite continuing efforts and improvements in in-river conservation, they are in steep decline across their range. Salmon from rivers across Europe migrate along similar routes, where they have, historically, been subject to commercial netting. This mixed stock exploitation has the potential to devastate weak and declining populations where they are exploited indiscriminately. Despite various tagging and marking studies, the effect of marine exploitation and the marine element of the salmon lifecycle in general, remain the "black-box" of salmon management. In a number of Pacific salmonid species and in several regions within the range of the Atlantic salmon, genetic stock identification and mixed stock analysis have been used successfully to quantify exploitation rates and identify the natal origins of fish outside their home waters - to date this has not been attempted for Atlantic salmon in the south of their European range.

Results

To facilitate mixed stock analysis (MSA) of Atlantic salmon, we have produced a baseline of genetic data for salmon populations originating from the largest rivers from Spain to northern Scotland, a region in which declines have been particularly marked. Using 12 microsatellites, 3,730 individual fish from 57 river catchments have been genotyped. Detailed patterns of population genetic diversity of Atlantic salmon at a sub-continent-wide level have been evaluated, demonstrating the existence of regional genetic signatures. Critically, these appear to be independent of more commonly recognised terrestrial biogeographical and political boundaries, allowing reporting regions to be defined. The implications of these results on the accuracy of MSA are evaluated and indicate that the success of MSA is not uniform across the range studied; our findings indicate large differences in the relative accuracy of stock composition estimates and MSA apportioning across the geographical range of the study, with a much higher degree of accuracy achieved when assigning and apportioning to populations in the south of the area studied. This result probably reflects the more genetically distinct nature of populations in the database from Spain, northwest France and southern England. Genetic stock identification has been undertaken and validation of the baseline microsatellite dataset with rod-and-line and estuary net fisheries of known origin has produced realistic estimates of stock composition at a regional scale.

Conclusions

This southern European database and supporting phylogeographic and mixed-stock analyses of net samples provide a unique tool for Atlantic salmon research and management, in both their natal rivers and the marine environment. However, the success of MSA is not uniform across the area studied, with large differences in the relative accuracy of stock composition estimates and MSA apportioning, with a much higher degree of accuracy achieved when assigning and apportioning to populations in the south of the region. More broadly, this study provides a basis for long-term salmon management across the region and confirms the value of this genetic approach for fisheries management of anadromous species.     

Variation in Gillraker Number During Growth of the Sea Bass, Dicentrarchus labrax (Perciformes: Moronidae), Reared at Different Salinities

A marked salinity-related decrease in gillraker number in sea bass samples during growth was documented. All specimens share the same genetic stock and rearing conditions were constant during early ontogeny. Variation in gillraker number could be related to the ecophenotypism of this character but selection can not be excluded. Results obtained from reared specimens were compared with those reported in the literature and with data collected from wild stocks. Attention is focused on the pitfalls that the use of this character may have on the taxonomy of fish species.     

It is the economy,stupid! Projecting the fate of fish populations using ecological–economic modeling

Four marine fish species are among the most important on the world market: cod, salmon, tuna, and sea bass. While the supply of North American and European markets for two of these species – Atlantic salmon and European sea bass – mainly comes from fish farming, Atlantic cod and tunas are mainly caught from wild stocks. We address the question what will be the status of these wild stocks in the midterm future, in the year 2048, to be specific. Whereas the effects of climate change and ecological driving forces on fish stocks have already gained much attention, our prime interest is in studying the effects of changing economic drivers, as well as the impact of variable management effectiveness. Using a process‐based ecological–economic multispecies optimization model, we assess the future stock status under different scenarios of change. We simulate (i) technological progress in fishing, (ii) increasing demand for fish, and (iii) increasing supply of farmed fish, as well as the interplay of these driving forces under different scenarios of (limited) fishery management effectiveness. We find that economic change has a substantial effect on fish populations. Increasing aquaculture production can dampen the fishing pressure on wild stocks, but this effect is likely to be overwhelmed by increasing demand and technological progress, both increasing fishing pressure. The only solution to avoid collapse of the majority of stocks is institutional change to improve management effectiveness significantly above the current state. We conclude that full recognition of economic drivers of change will be needed to successfully develop an integrated ecosystem management and to sustain the wild fish stocks until 2048 and beyond.     

Refuge use by fish as a function of body length-related metabolic expenditure and predation risks

Theory predicts that staying in a refuge has benefits in terms of predator avoidance and costs in terms of lost feeding opportunities. In this study, we investigated how the relative importance of these costs and benefits changes with increasing body length. This is of particular interest in animals such as fish, which show continuous growth throughout their lives. Our results suggest that larger fish are subject to lower predation risks and are less affected by food deprivation than small fish, with fish decreasing their responses to food-deprivation treatments more strongly with increasing body length than to predation treatments. This may explain our observation that large fish emerged later from a refuge than small ones and spent shorter times outside the refuge. The key role of differential responses to food deprivation was further illustrated by the finding that the relative weight loss of individual fish was strongly correlated with a reduction in hiding time even in the absence of body length differences. The importance of inter-individual differences in metabolic rates for the decision-making behaviour of animals is discussed.     

Biomass estimation of orange roughy: a summary and evaluation of techniques for measuring stock size of a deep-water fish species in New Zealand

A number of techniques have been employed to measure biomass of orange roughy in New Zealand. Time series of stratified random trawl surveys in a number of areas over periods of 5–10 years have given relative abundance indices, which have been used in stock reduction analyses to estimate true biomass. This has given confident results for the Chatham Rise stock, and surveys have also shown strong trends in other regions. Acoustic surveys have been carried out on three grounds. They can give relative indices of orange roughy abundance in areas of fiat or medium sloping bottom, and have the potential for estimation of absolute biomass from a single survey. Egg production surveys have been employed on two grounds on the east coast of the North Island, where conditions of tight spawning aggregations and steep bottom topography have limited the success of other methods. Both daily fecundity reduction and annual egg production methods have been used. These have given estimates of true biomass from one-off surveys, although results are imprecise. Both unstandardized and standardized analyses of commercial catch-per-unit-effort data have given relative indices of abundance, which have formed an important part of stock assessment for several fisheries. No single technique used to measure the size of orange roughy stocks has proven ideal or appropriate in all New Zealand situations. All have advantages and disadvantages, depending on the characteristics of the fishing area and fish behaviour. For two areas, a combination of methods have been applied, which has given more confident results than those from a single technique.     

Precautionary Coastal States’ Jurisdiction

Throughout the life of the 1959 Antarctic Treaty there has been considerable development in the law of the sea. Negotiated following the 1958 First United Nations Conference on the Law of the Sea, at which the customary international law concepts of the territorial sea and continental shelf were codified into treaty law, the law of the sea has since developed through state practice and most importantly through the 1982 United Nations Convention on the Law of the Sea. Whatever the merits of examining the interaction between Antarctica and the law of the sea have been in the past, there is much to suggest that the general significance of such issues is growing, especially as states seek to determine the outer limits of their continental shelf claims and in doing so determine Antarctic baselines. This article examines these issues from a general law of the sea perspective, taking into account the impact of the Antarctic Treaty while reviewing Australian practice in particular.     

Assigned Territories, Family/Clan/Communal Holdings, and Common-Pool Resources in the Taimyr Autonomous Region, Northern Russia

This paper describes an indigenous hunting/fishing/trapping economy in the Taimyr Autonomous Region, northern Russia, and traces the continuities and developments in property since the collapse of the Soviet command economy in 1991. Indigenous relations to hunting grounds and renewable resources are discussed with ethnographic case material from Dolgan and Nganasan communities. Land tenure is analyzed in terms of inclusive and exclusive property and informal and formal resource management. The asymmetric growth and distribution of common-pool territories and private holdings is a central issue. A number of factors when examined together appear to favor common property and traditional management including ancestral frames of morality and access, crosscutting kin relationships, principles of ownership and mutual aid, cooperative hunting, sharing of meat and fish, as well as migration patterns of prey species and relative increases in the cost of freight transport since 1991. In addition, private holdings often make commercial sales and generally have better access to urban centers, while they are more closely regulated through land, tax, and environment offices of local government.