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1.
Environ Sci Policy ; 117: 34-45, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34744509

RESUMEN

The frequency and severity of shocks to food systems is accelerating globally, exemplified by the current COVID-19 outbreak. In low- and middle-income countries, the impacts have exacerbated existing food system vulnerabilities and poverty. Governments and donors must respond quickly, but few tools are available that identify interventions to build food system resilience, or emerging opportunities for transformation. In this paper we reflect on the application of a systems-based rapid assessment which we applied across 11 Indo-Pacific countries in May-July 2020. Our approach was shaped by three design parameters: the integration of key informants' perspectives engaged remotely within the countries, applicability to diverse food systems and COVID-19 experiences across the region, and the consideration of food systems as complex systems. For the rapid assessment we adopted an analytical framework proposed by Allen and Prosperi (2016). To include a development lens, we added the analysis of vulnerable groups and their exposure, impacts, recovery potential and resilience, and pro-poor interventions. We concluded that the framework and approach facilitated integration and triangulation of disparate knowledge types and data to identify priority interventions and was sufficiently flexible to be applied across food systems, at both national, sub-national and commodity scales. The step-wise method was simple and enabled structured inquiry and reporting. Although the systems concepts appeared more easily transferrable to key informants in some countries than others, potentially transformational interventions were identified, and also some risks of maladaptation. We present a refined framework that emphasises analysis of political, economic and institutional drivers of exposure and vulnerability, the constraints that they pose for building recovery potential and resilience, and trade-offs amongst winners and losers inherent in proposed interventions.

2.
Ecology ; 102(12): e03519, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34449876

RESUMEN

Species assemblages often have a non-random nested organization, which in vertebrate scavenger (carrion-consuming) assemblages is thought to be driven by facilitation in competitive environments. However, not all scavenger species play the same role in maintaining assemblage structure, as some species are obligate scavengers (i.e., vultures) and others are facultative, scavenging opportunistically. We used a database with 177 vertebrate scavenger species from 53 assemblages in 22 countries across five continents to identify which functional traits of scavenger species are key to maintaining the scavenging network structure. We used network analyses to relate ten traits hypothesized to affect assemblage structure with the "role" of each species in the scavenging assemblage in which it appeared. We characterized the role of a species in terms of both the proportion of monitored carcasses on which that species scavenged, or scavenging breadth (i.e., the species "normalized degree"), and the role of that species in the nested structure of the assemblage (i.e., the species "paired nested degree"), therefore identifying possible facilitative interactions among species. We found that species with high olfactory acuity, social foragers, and obligate scavengers had the widest scavenging breadth. We also found that social foragers had a large paired nested degree in scavenger assemblages, probably because their presence is easier to detect by other species to signal carcass occurrence. Our study highlights differences in the functional roles of scavenger species and can be used to identify key species for targeted conservation to maintain the ecological function of scavenger assemblages.


Asunto(s)
Falconiformes , Cadena Alimentaria , Animales , Peces , Fenotipo , Vertebrados
3.
Animals (Basel) ; 11(4)2021 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33918029

RESUMEN

Companion animal management in Australian remote Aboriginal communities (rAcs) is a complex problem with multiple stakeholders involved, with differing needs, knowledge, power and resources. The Comm4Unity (Cycle of Multiple Methods for Unity-For Community) approach was designed to address such problems. This study represents the second step of the Comm4Unity framework, where a causal loop analysis (CLA) was adapted and tested as a tool to address the issue of dog overpopulation in Wurrumiyanga, and in particular the systemic causes of the problem and necessary transformational management solutions. Ten focus group discussions (FGDs) were held amongst three of the four stakeholder groups identified during the first step in the analysis. The CLA identified 13 positive feedback loops, which drive vicious cycles and perpetuate the dog overpopulation issue. All three groups agreed and developed 22 solutions to address the causes of dog overpopulation. Despite the differences in the framings of the three groups, "training" and "education" were both the top priority solutions for all three groups. The majority of the solutions discussed by the groups were not only transformational but also social, requiring collaboration. This study was successful in so far as transformational actions were co-developed by all FGDs, which may have also built capacity and agency amongst the local community to implement them as a cohesive group.

4.
Animals (Basel) ; 11(3)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652768

RESUMEN

Companion animal management in Australian remote Aboriginal communities (rAcs) is a complex problem, with multiple stakeholders involved with differing needs, knowledge, power and resources. We present our CoMM4Unity approach, a participatory systemic action research process designed to address such problems. In the first step, frame analysis is used to analyse stakeholders' perspectives, knowledge types and power dynamics to determine their relative roles in animal management. Twenty individuals were interviewed from stakeholder groups involved in animal management in the remote, island rAc of Wurrumiyanga, Tiwi Islands. Frame analysis indicated that stakeholders aligned into four groups with distinct identity frames, knowledge types and power frames: Indigenous Locals, Indigenous Rangers, Non-Indigenous Locals and Animal Managers. All four groups shared overlapping perceptions about companion animals in Wurrumiyanga, and agreed that dog overpopulation was the primary issue. However, the groups differed in their strength of opinions about how dogs should be managed. Therefore, the situation is not one of diametrically opposing frames but more a misalignment of goals and values. Our application showed that frame analysis can reveal subtle variations in stakeholder groups' identities, goals and values, and hence how they prioritise management measures.

5.
Agric Syst ; 191: 103137, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36570634

RESUMEN

Context: The COVID-19 pandemic has impacted global food systems. This has led to different strategies by communities, governments, and businesses involved in food systems to mitigate and adapt to the unfolding pandemic. Small Island Developing States are particularly exposed to the conflation of risks from COVID-19 disease, economic downturns, underlying climate vulnerabilities and biosecurity risks. Objective: Our study aimed to identify the food systems vulnerabilities, impacts, and opportunities for supporting resilience and sustainable development in selected Pacific Island countries, Papua New Guinea, and Timor-Leste. The study focused on the impacts from the first six months of the pandemic (February-July 2020), with remote data collection and analysis done between May and July 2020. Methods: We conducted 67 interviews, and triangulated information with desktop and news sources emerging at the time. We present results on the effect on smallholder livelihoods, supply chains, governance, communities and employment. Overall, the major impacts of COVID-19 have been on economies, posing risks to future food security and further hampering progress towards key Sustainable Development Goals. Results and conclusions: We found that unemployment and economic contraction have been the most severe effects to date, with long-term consequences for food value chains and smallholder farmers. Disruptions to tourism, labour migration, and remittances have led to varying socio-economic impacts throughout the region. Vulnerable groups, notably women, urban poor, and youth, have been disproportionately affected by unemployment. Timor-Leste has had some social protection measures, whereas in Pacific Countries these have been varied. The lockdowns and State of Emergency initially influenced the distribution and marketing of food, but local food economies are starting to stabilise. The continued functioning of international food supply chains reduced the risk of food insecurity in high import dependent nations, notably import dependent countries like Tuvalu and Kiribati. Significance: The results have significance for three recovery pathways. The first recovery pathway relates to revisiting value chains in light of restricted travel. The second recovery pathway exists through leveraging the adaptive capacities of communities to stimulate innovative agriculture that also integrates climate adaptation and nutrition. The third recovery pathway relates to addressing the structural challenges that perpetuate inequalities and poverty while finding new ways of implementing inclusive policies and research. Our study presents a set of comparative examples of managing a food system shock that can inform future systems-oriented research and policy for sustainable development.

6.
Glob Chang Biol ; 25(9): 3005-3017, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31127672

RESUMEN

Understanding the distribution of biodiversity across the Earth is one of the most challenging questions in biology. Much research has been directed at explaining the species latitudinal pattern showing that communities are richer in tropical areas; however, despite decades of research, a general consensus has not yet emerged. In addition, global biodiversity patterns are being rapidly altered by human activities. Here, we aim to describe large-scale patterns of species richness and diversity in terrestrial vertebrate scavenger (carrion-consuming) assemblages, which provide key ecosystem functions and services. We used a worldwide dataset comprising 43 sites, where vertebrate scavenger assemblages were identified using 2,485 carcasses monitored between 1991 and 2018. First, we evaluated how scavenger richness (number of species) and diversity (Shannon diversity index) varied among seasons (cold vs. warm, wet vs. dry). Then, we studied the potential effects of human impact and a set of macroecological variables related to climatic conditions on the scavenger assemblages. Vertebrate scavenger richness ranged from species-poor to species rich assemblages (4-30 species). Both scavenger richness and diversity also showed some seasonal variation. However, in general, climatic variables did not drive latitudinal patterns, as scavenger richness and diversity were not affected by temperature or rainfall. Rainfall seasonality slightly increased the number of species in the community, but its effect was weak. Instead, the human impact index included in our study was the main predictor of scavenger richness. Scavenger assemblages in highly human-impacted areas sustained the smallest number of scavenger species, suggesting human activity may be overriding other macroecological processes in shaping scavenger communities. Our results highlight the effect of human impact at a global scale. As species-rich assemblages tend to be more functional, we warn about possible reductions in ecosystem functions and the services provided by scavengers in human-dominated landscapes in the Anthropocene.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Clima , Peces , Humanos , Vertebrados
7.
Trop Med Infect Dis ; 3(4)2018 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-30297603

RESUMEN

The impacts of free-roaming canids (domestic and wild) on public health have long been a concern in Australian Indigenous communities. We investigated the prevalence of zoonotic helminth diseases in dogs and sympatric dingoes, and used radio telemetry to measure their spatial overlap, in an Aboriginal community in the Wet Tropics of Australia. Samples collected from dingoes and dogs showed high levels of infection with the zoonotic hookworm, Ancylostoma caninum. Dingoes were also positive for A. ceylanicum infection (11.4%), but dogs were infection free. Whipworm, Trichuris vulpis, infection was far more prevalent in necropsies of domestic dogs (78.6%) than dingoes (3.7%). Dogs were free from Dirofilaria immitis infection, while dingoes recorded 46.2% infection. Eleven dingoes and seven free-roaming domestic dogs were fitted with Global Positioning System collars and tracked over an extended period. Dingo home-ranges almost completely overlapped those of the domestic dogs. However, dingoes and dogs did not utilise the same area at the same time, and dogs may have avoided dingoes. This spatial overlap in resource use presents an opportunity for the indirect spill-over and spill-back of parasites between dogs and dingoes. Tracking and camera traps showed that the community rubbish tip and animal carcasses were areas of concentrated activity for dogs and dingoes.

8.
Animals (Basel) ; 8(5)2018 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-29702585

RESUMEN

As the global population of free-ranging domestic dogs grows, there is increasing concern about impacts on human health and wildlife conservation. Effective management of dog populations requires reliable information on their diet, feeding behavior, and social ecology. Free-ranging dogs are reliant on humans, but anthropogenic food subsidies, particularly human faeces (i.e., coprophagy) have not previously been fully quantified. In this study we assess the contributions of different food types to the diet, and their influences on the social behaviour of free-ranging dogs in communal lands of rural Zimbabwe, with a focus on coprophagy. Free-ranging dog diets, body condition, and sociology were studied amongst 72 dogs over 18 months using scat analysis and direct observations. Human faeces constituted the fourth most common item in scats (56% occurrence) and contributed 21% by mass to the observed diet. Human faeces represented a valuable resource because relative to other food items it was consistently available, and of higher nutritional value than ‘sadza’ (maize porridge, the human staple and primary human-derived food), yielding 18.7% crude protein and 18.7 KJ/kg gross energy, compared to 8.3% and 18.5 KJ/kg for sadza, respectively. Human faeces had protein and energy values equivalent to mammal remains, another important food item. Dog condition was generally good, with 64% of adult females and 74% of adult males in the highest two body condition scores (on a five point scale), suggesting a plentiful and high quality food supply. Dogs largely fed alone, perhaps as a consequence of the small, inert, and spatially dispersed items that comprise their diet, and its abundance. We discuss the relationships between sanitation, human development, the supply of human faeces, female dog fertility, and population control.

9.
Animals (Basel) ; 8(5)2018 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-29701647

RESUMEN

This study examined dog and cat demographics, roaming behaviours, and interspecific interactions in a remote Aboriginal island community using multiple methods. Our results revealed temporal differences between the roaming behaviours of dogs, cats, and wildlife. Dogs showed crepuscular behaviour, being active around dawn (5:30 a.m. to 9:30 a.m.) and dusk (6:00 p.m. and 11:35 p.m.). The majority of cats were active between dawn (6:30 a.m.) and dusk (7:30 p.m.) and travelled shorter distances than dogs. However, some cats were also observed roaming between dusk and dawn, and were likely to be hunting since flightless wildlife were also recorded on our remote-sensing cameras during this time. These baseline data provide evidence to suggest that new management programs are needed to reduce the number of roaming cats and therefore their potential impacts on native wildlife. Collaborations between Aboriginal owners and other stakeholders is necessary to design innovative and effective animal management and policy on the island.

10.
Agric Syst ; 165: 344-353, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32287945

RESUMEN

Food insecurity persists in many parts of Africa and Asia, despite ongoing agricultural research for development (AR4D) interventions. This is resulting in a growing demand for alternative approaches to designing and evaluating interventions in complex systems. Theory of Change (ToC) is an approach which may be useful because it enables stakeholders to present and test their theories and assumptions about why and how impact may occur, ideally within an environment conducive to iterative reflection and learning. However, ToC is yet to be appropriately mainstreamed into development by donors, researchers and practitioners. We carried out a literature review, triangulated by interviews with 26 experts in African and Asian food security, consisting of researchers, advisors to programs, and donors. Although 17 (65%) of the experts had adopted ToC, their responses and the literature revealed four challenges to mainstreaming: (i) different interpretations of ToC; (ii) incoherence in relationships among the constituent concepts of ToC; (iii) confused relationships between ToC and project "logframes"; and (iv) limitations in necessary skills and commitment for enacting ToC. A case study of the evolution of a ToC in a West African AR4D project over 4 years which exemplified these challenges is presented. Five recommendations arise to assist the mainstreaming of ToC: (i) select a type of ToC suited to the relative complexity of the problem and focal system of interest; (ii) state a theory or hypotheses to be tested as the intervention progresses; (iii) articulate the relationship between the ToC and parallel approaches (e.g. logframe); (iv) accept that a ToC is a process, and (v) allow time and resources for implementers and researchers to develop ToC thinking within projects. Finally, we suggest that communities of practice should be established among AR4D and donor organisations to test, evaluate and improve the contribution that ToCs can make to sustainable food security and agricultural development.

11.
Ecol Evol ; 7(21): 8927-8935, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29152188

RESUMEN

In Australia, dingoes (Canis lupus dingo) have been implicated in the decline and extinction of a number of vertebrate species. The lowland Wet Tropics of Queensland, Australia is a biologically rich area with many species of rainforest-restricted vertebrates that could be threatened by dingoes; however, the ecological impacts of dingoes in this region are poorly understood. We determined the potential threat posed by dingoes to native vertebrates in the lowland Wet Tropics using dingo scat/stomach content and stable isotope analyses of hair from dingoes and potential prey species. Common mammals dominated dingo diets. We found no evidence of predation on threatened taxa or rainforest specialists within our study areas. The most significant prey species were northern brown bandicoots (Isoodon macrourus), canefield rats (Rattus sordidus), and agile wallabies (Macropus agilis). All are common species associated with relatively open grass/woodland habitats. Stable isotope analysis suggested that prey species sourced their nutrients primarily from open habitats and that prey choice, as identified by scat/stomach analysis alone, was a poor indicator of primary foraging habitats. In general, we find that prey use by dingoes in the lowland Wet Tropics does not pose a major threat to native and/or threatened fauna, including rainforest specialists. In fact, our results suggest that dingo predation on "pest" species may represent an important ecological service that outweighs potential biodiversity threats. A more targeted approach to managing wild canids is needed if the ecosystem services they provide in these contested landscapes are to be maintained, while simultaneously avoiding negative conservation or economic impacts.

12.
One Health ; 3: 66-69, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28616506

RESUMEN

Ancylostoma ceylanicum is the common hookworm of domestic dogs and cats throughout Asia, and is an emerging but little understood public health risk in tropical northern Australia. We investigated the prevalence of A. ceylanicum in soil and free-ranging domestic dogs at six rainforest locations in Far North Queensland that are Indigenous Australian communities and popular tourist attractions within the Wet Tropics World Heritage Area. By combining PCR-based techniques with traditional methods of hookworm species identification, we found the prevalence of hookworm in Indigenous community dogs was high (96.3% and 91.9% from necropsy and faecal samples, respectively). The majority of these infections were A. caninum. We also observed, for the first time, the presence of A. ceylanicum infection in domestic dogs (21.7%) and soil (55.6%) in an Indigenous community. A. ceylanicum was present in soil samples from two out of the three popular tourist locations sampled. Our results contribute to the understanding of dogs as a public health risk to Indigenous communities and tourists in the Wet Tropics. Dog health needs to be more fully addressed as part of the Australian Government's commitments to "closing the gap" in chronic disease between Indigenous and other Australians, and encouraging tourism in similar locations.

13.
Vet Parasitol ; 215: 6-10, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26790730

RESUMEN

Heartworm (Dirofilaria immitis) is a parasitic nematode responsible for canine and feline cardiopulmonary dirofilariasis and human zoonotic filariosis in both tropical and temperate regions throughout the world. Importantly, this study in the Wet Tropics of Far North Queensland found D. immitis remains at high prevalence (72.7%) in wild dingoes in low density housing areas in Australia. This prevalence is equivalent to the highest levels seen in wild dogs in Australia and represents an ongoing risk to domestic dogs, cats and humans. In contrast, in higher density residential areas prevalence was significantly lower (16.7%, p=0.001). It is possible that chemotherapeutic heartworm (HW) prevention in domestic dogs in these higher density housing areas is helping to control infection in the resident dingo population. Five dingoes killed in council control operations around Atherton, a non-endemic HW region in the Wet Tropics, were all negative for HW likely due to the colder climate of the region restricting transmission of the disease. This survey highlights the importance of dingoes as reservoir hosts of HW disease and that the subsequent risk of infection to companion animals and humans depends on local factors such as housing density, possibly linked to chemotherapeutic HW control in domestic dogs and climate. Our findings show that veterinary clinicians need to ensure that pet owners are aware of HW disease and do not become complacent about HW chemoprohylaxis in areas which support dingo populations.


Asunto(s)
Dirofilaria immitis/aislamiento & purificación , Dirofilariasis/parasitología , Reservorios de Enfermedades/veterinaria , Enfermedades de los Perros/parasitología , Animales , Antígenos Helmínticos , Australia/epidemiología , Dirofilariasis/epidemiología , Enfermedades de los Perros/epidemiología , Perros , Femenino , Masculino
14.
Conserv Biol ; 30(4): 816-26, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26511405

RESUMEN

Community-based conservation programs in developing countries are often based on the assumption that heteronomous motivation (e.g., extrinsic incentives such as economic rewards and pressure or coercion to act) will incite local communities to adopt conservation behaviors. However, this may not be as effective or sustainable as autonomous motivations (e.g., an intrinsic desire to act due to inherent enjoyment or self-identification with a behavior and through freedom of choice). We analyzed the comparative effectiveness of heteronomous versus autonomous approaches to community-based conservation programs through a case study of Sumatran orangutan (Pongo abelii) conservation in 3 villages in Indonesia. Each village had a different conservation program design. We surveyed people (n = 240) to determine their motivations for and behavior changes relative to orangutan and orangutan habitat (forest) protection. Heteronomous motivations (e.g., income from tourism) led to greater self-reporting of behavior change toward orangutan protection. However, they did not change self-reported behavior toward forest (i.e., orangutan habitat) protection. The most effective approach to creating self-reported behavior change throughout the community was a combination of autonomous and heteronomous motivations. Individuals who were heteronomously motivated to protect the orangutan were more likely to have changed attitudes than to have changed their self-reported behavior. These findings demonstrate that the current paradigm of motivating communities in developing countries to adopt conservation behaviors primarily through monetary incentives and rewards should consider integrating autonomous motivational techniques that promote the intrinsic values of conservation. Such a combination has a greater potential to achieve sustainable and cost-effective conservation outcomes. Our results highlight the importance of using in-depth sociopsychological analyses to inform the design and implementation of community-based conservation programs.


Asunto(s)
Conservación de los Recursos Naturales , Motivación , Pongo abelii , Animales , Ecosistema , Humanos , Indonesia , Opinión Pública
15.
N S W Public Health Bull ; 21(5-6): 139-45, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20637171

RESUMEN

The evident and unresolved health disparity between Aboriginal and other Australians is testament to a history of systematic disenfranchisement. Stigma, lack of appropriate services and the expense of delivering services in remote settings make it impossible to adequately address mental health needs, including suicide, solely using a mainstream medical approach. Nor do mainstream approaches accommodate the relationship between Aboriginal health and connectedness to land, whether traditional or new land, remote or metropolitan. This review describes how caring-for-country projects on traditional lands in remote locations may provide a novel way to achieve the linked goals of climate change adaptation with co-benefits for social and emotional wellbeing.


Asunto(s)
Cambio Climático , Servicios de Salud del Indígena , Salud Mental , Nativos de Hawái y Otras Islas del Pacífico , Humanos , Terapias Mente-Cuerpo , Características de la Residencia
16.
Genet Res (Camb) ; 91(6): 395-412, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20122296

RESUMEN

Effective population size (Ne) is an important parameter in the conservation of genetic diversity. Comparative studies of empirical data that gauge the relative accuracy of Ne methods are limited, and a better understanding of the limitations and potential of Ne estimators is needed. This paper investigates genetic diversity and Ne in four populations of wild anadromous Atlantic salmon (Salmo salar L.) in Europe, from the Rivers Oir and Scorff (France) and Spey and Shin (Scotland). We aimed to understand present diversity and historical processes influencing current population structure. Our results showed high genetic diversity for all populations studied, despite their wide range of current effective sizes. To improve understanding of high genetic diversity observed in the populations with low effective size, we developed a model predicting present diversity as a function of past demographic history. This suggested that high genetic diversity could be explained by a bottleneck occurring within recent centuries rather than by gene flow. Previous studies have demonstrated the efficiency of coalescence models to estimate Ne. Using nine subsets from 37 microsatellite DNA markers from the four salmon populations, we compared three coalescence estimators based on single and dual samples. Comparing Ne estimates confirmed the efficiency of increasing the number and variability of microsatellite markers. This efficiency was more accentuated for the smaller populations. Analysis with low numbers of neutral markers revealed uneven distributions of allelic frequencies and overestimated short-term Ne. In addition, we found evidence of artificial stock enhancement using native and non-native origin. We propose estimates of Ne for the four populations, and their applications for salmon conservation and management are discussed.


Asunto(s)
Variación Genética , Salmo salar/genética , Migración Animal , Animales , Genética de Población , Densidad de Población
17.
Pest Manag Sci ; 58(6): 595-608; discussion 622-9, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12138626

RESUMEN

The sea louse (Lepeophtheirus salmonis Krøyer) is a major health problem for both farmed and wild salmonids. This paper investigates louse epidemiology and management in the salmon-farming zone of western Scotland. Based on a review of the marine ecology of wild salmon (Salmo salar L) and sea trout (Salmo trutta L), and catch and farm production statistics, best estimates were made for numbers of wild and farm hosts present in coastal waters in March-June 2000. Applying data for ovigerous female louse infections and fecundity, the sources and risks of larval transmission to wild salmon and sea trout were modelled. Farm salmon in the second spring of production were the primary host group (98% of fish), while numbers of wild salmonids (< 1%) and escaped farm salmon (2%) were relatively insignificant. Farm salmon produced 97% of louse eggs at high levels (eight ovigerous lice per fish), and 78% at low levels (one per fish). Wild salmonids produced < 1% of eggs under both scenarios, but escaped farm salmon produced 3% and 21%, respectively. All hosts potentially cross-infect one another, but farm salmon are more likely to infect wild and farm smolts, and also other farm salmon. Monitoring of lice on sea trout in June 1998-2000 by the Association of West Coast Fisheries Trusts corroborated the model's conclusions. Localised epizootics occurred every year and coincided with the presence of ovigerous lice on local farms. In areas of mixed-year class production on farms, epizootics were evident every spring, but occurred every second spring in areas of single-year class production. In 1998-2000 at least 14-40% of sea trout were infected with potentially lethal infestations of lice. Ovigerous louse levels of < 0.005 per fish were required on farm salmon in the spring of 2000 to produce less eggs than those emitted by wild salmonids. With the industry's continued expansion, and thus increased numbers of farm salmon, a target of zero ovigerous lice will be required on farms to minimise impacts on wild salmonids. Due to the limited long-term efficacy and availability of louse medicines, management strategies are discussed which will improve control, including single-year class production over large areas, alternate S1-S1/2 smolt inputs, and 11-month production cycles.


Asunto(s)
Animales Salvajes/parasitología , Copépodos/fisiología , Enfermedades de los Peces/epidemiología , Explotaciones Pesqueras/métodos , Enfermedades Parasitarias en Animales/epidemiología , Salmonidae/parasitología , Animales , Antiparasitarios/uso terapéutico , Ecología , Femenino , Enfermedades de los Peces/tratamiento farmacológico , Enfermedades de los Peces/parasitología , Interacciones Huésped-Parásitos , Masculino , Modelos Biológicos , Enfermedades Parasitarias en Animales/tratamiento farmacológico , Control de Plagas , Salmonidae/crecimiento & desarrollo , Escocia/epidemiología , Agua de Mar , Factores de Tiempo
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