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1.
J Environ Manage ; 289: 112366, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33848883

RESUMO

Pro-environmental behaviours (PEBs) are important for mitigation and restoration efforts in the Anthropocene. As recreationists are motivated to engage in leisure activities to increase their own personal wellbeing, we submit that threats to wellbeing (an egocentric motivator) predict engagement in PEBs amongst recreationists. We also predict that differences in experiences across groups of recreationists leads to differences in PEB engagement. Using an online survey, we test our two hypotheses (if recreationists perceive there is a threat to their wellbeing and that their behaviours can yield environmental successes, then they will be more likely to engage in PEBs, and if recreationists differ in recreational experiences then they will demonstrate differences in PEB engagement) amongst outdoor recreationists, specifically Canadian rainbow trout and steelhead anglers in British Columbia (n = 894 respondents). We define 'threat to wellbeing' as the interaction of environmental threat-perceptions of used environments for fishing, and level of centrality fishing has to one's lifestyle. To test our first hypothesis, we conducted three linear regressions corresponding to three different PEBs related to catch-and-release (C&R) fishing. Our egocentric predictor 'threat to wellbeing' was only significant for one out of the three PEBs tested, showing mixed support for our first hypothesis. It is of note that 'environmental threat perceptions' and one's belief in successes resulting from PEB engagement were found to be significant predictors for all three PEBs tested. These results suggest that predictors of PEB may not always be transferable across PEBs relating to recreational activities, and environmental threat perception and one's belief in successes resulting from PEB engagement are strong predictors of PEBs amongst recreationists. To test our second hypothesis, we conducted a Kruskal Wallis test to determine if there were significant differences across angler groups in PEB predictor scores and PEB engagement and conducted pairwise population Z-tests to determine proportional participation rates across angler groups for the three PEBs and PEB predictors investigated. Experiences were found to shape predictors of PEBs, as well as likelihood to engage in PEBs, as different angler groups targeting different fish (i.e., rainbow trout vs steelhead) and using different aquatic habitats (i.e., rivers vs. lakes) demonstrated significantly different scores for PEB predictors, as well as significantly different likelihood to engage in two of the three PEBs tested. These findings support the notion that recreationists are not a homogenous group, and that their beliefs and resulting behaviours during recreational activities are determined by their experiences in nature and can be influenced by the species with which they interact, and the habitats they use for recreation.


Assuntos
Pesqueiros , Recreação , Animais , Colúmbia Britânica , Conservação dos Recursos Naturais , Ecossistema , Lagos
2.
Fish Res ; 240: 105961, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36540896

RESUMO

The COVID-19 pandemic and corresponding public health mitigation strategies have altered many facets of human life. And yet, little is known about how public health measures have impacted complex socio-ecological systems such as recreational fisheries. Using an online snowball survey, we targeted resident anglers in Ontario, Canada, to obtain preliminary insights on how the pandemic has impacted recreational fishing and related activity. We also explored angler perspectives on pandemic-related restrictions and other aspects of fisheries management. Our results point to the value of recreational fisheries for the mental and physical well-being of participants, as well as the value and popularity of outdoor recreation during a pandemic. Although angling effort and fish consumption appeared to decline during the early phases of the pandemic, approximately 21 % of the anglers who responded to our survey self-identified as new entrants who had begun or resumed fishing in that time. Self-reported motivations to fish during the pandemic suggest that free time, importance to mental and physical health, and desires for self-sufficiency caused some anglers to fish more, whereas a lack of free time, poor or uncertain accessibility, and perceived risks caused some anglers to fish less. Respondents also expressed their desires for more clear and consistent communication about COVID-19 fishing restrictions from governments, and viewed angling as a safe pandemic activity. Information on recreational angler behaviours, motivations, and perspectives during the pandemic may prove valuable to fisheries managers and policy makers looking to optimize their strategies for confronting this and other similar crises.

3.
J Therm Biol ; 47: 63-74, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25526656

RESUMO

Anthropogenic climate change is altering temperature regimes for coastal marine fishes. However, given that temperature changes will not occur in isolation of other stressors, it is necessary to explore the potential consequences of stress on the thermal tolerances and preferences of tropical marine fish in order to understand the thresholds for survival, and predict the associated coastal ecological consequences. In this study, we used exogenous cortisol injections to investigate the effects of a thermal challenge on checkered puffers (Sphoeroides testudineus) as a secondary stressor. There were no significant differences between control and cortisol-treated fish 48h following cortisol treatment for swimming ability (using a chase to exhaustion protocol), blood glucose concentrations or standard metabolic rate. In the lab, control and cortisol-treated puffers were exposed to ambient (29.1±1.5°C), ambient +5°C (heat shock) and ambient -5°C (cold shock) for 4h and to evaluate the consequences of abrupt temperature change on puff performance and blood physiology. Following cold shock, control fish exhibited increases in cortisol levels and weak 'puff' performance. Conversely, fish dosed with cortisol exhibited consistently high cortisol levels independent of thermal treatment, although there was a trend for an attenuated cortisol response in the cortisol-treated fish to the cold shock treatment. A 20-day complementary field study conducted in the puffer's natural habitat, a tidal creek in Eleuthera, The Bahamas, revealed that cortisol-injected fish selected significantly cooler temperatures, measured using accumulated thermal units, when compared to controls. These results, and particularly the discrepancies between consequences documented in the laboratory and the ecological trends observed in the field, highlight the need to establish the link between laboratory and field data to successfully develop management policies and conservation initiatives with regards to anthropogenic climate change.


Assuntos
Resposta ao Choque Frio/efeitos dos fármacos , Resposta ao Choque Térmico/efeitos dos fármacos , Hidrocortisona/farmacologia , Tetraodontiformes/fisiologia , Animais , Bahamas , Glicemia , Natação , Temperatura , Tetraodontiformes/metabolismo
4.
J Fish Biol ; 76(9): 2261-86, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20557662

RESUMO

Recent global and regional exercises have been undertaken to identify 100 questions of relevance to policy makers that, if answered, would improve decision making and conservation actions. These were intentionally broad, but all included themes and questions of relevance to aquatic and fisheries professionals (e.g. exploitation, habitat alteration, effectiveness of protected areas, migratory connectivity and environmental effects of aquaculture). Here, the content of the global 100 question exercise relevant to aquatic and fisheries issues is summarized and a critical analysis is provided. Many of the questions addressed in apparently unrelated themes and topics (e.g. terrestrial, agriculture and energy policy) have potential relevance to fisheries and aquatic habitats, which underlines the connectivity between terrestrial and aquatic realms. Given the intimate link between aquatic environmental problems and human activities (including culture and economics), greater understanding of the human dimension is required to inform decision making. Stakeholder perspectives need to be included as a core component of the fisheries management triangle (i.e. managing fish, habitat and people). The benefits and risks of conducting a global 100 questions exercise with an exclusive focus on questions of relevance to fisheries and aquatic practitioners are also considered. There is no question that evidence-based approaches to conservation are essential for addressing the many threats that face aquatic ecosystems and reverse the imperilment trends among ichthyofauna. It is still unclear, however, as to the extent to which 100 questions exercises will help to achieve conservation and management targets for aquatic resources. A global 100 questions exercise that focused on fisheries and aquatic issues would certainly help to generate interest and awareness sufficient to justify such an exercise.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Pesqueiros , Política Pública , Tomada de Decisões , Inquéritos e Questionários
5.
J Fish Biol ; 77(4): 947-62, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20840622

RESUMO

Bonefish Albula vulpes (n = 7) exercised to exhaustion and air exposed for 1 min as part of a catch-and-release angling event were found to excrete both ammonia and urea, but cortisol and lactate were below detectable levels. Urea made up a greater proportion of total nitrogen excretion from these fish at all time points following an angling event. When captive juvenile lemon sharks Negaprion brevirostris (n = 12) were exposed to a 30 s pulse of these chemicals [ammonia (500 mM), cortisol (20 µg l(-1) ), lactate (6 mM) or urea (3 mM)], they showed a significant reduction in the frequency of resting behaviours when exposed to ammonia and urea than when exposed to control water. It appears that products excreted by A. vulpes, particularly ammonia and urea, may provide an olfactory cue for the post-release predation of A. vulpes by N. brevirostris during catch-and-release angling events.


Assuntos
Sinais (Psicologia) , Peixes/fisiologia , Comportamento Predatório , Tubarões/fisiologia , Amônia/química , Animais , Estresse Fisiológico , Ureia/química
6.
Conserv Physiol ; 7(1): coz023, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191906

RESUMO

Anadromous fishes such as steelhead trout, Oncorhynchus mykiss, are exposed to a suite of infectious agents and migratory challenges during their freshwater migrations. We assessed infectious agent load and richness and immune system gene expression in gill tissue of Bulkley River (British Columbia, CA) steelhead captured at and upstream of a migratory barrier to evaluate whether infectious burdens impacted migration success. We further considered the potential influences of water temperature, sex and fish size on host infectious agents and transcription profiles. There were eight infectious agents detected in steelhead gill tissue, with high prevalence of the bacteria Candidatus Branchiomonas cysticola (80%) and Flavobacterium psychrophilum (95%) and the microparasite Sphaerothecum destruens (53%). Fish sampled at the falls had significantly greater relative loads of Ca. B. cysticola and F. psychrophilum, higher infectious agent richness and differential gene expression compared to fish captured upstream. Flavobacterium psychrophilum was only associated with immune gene expression (particularly humoral immunity) of fish sampled at the falls, while water temperature was positively correlated with genes involved in the complement system, metabolic stress and oxidative stress for fish captured upstream. This work highlights interesting differences in agent-host interactions across fisheries and suggests that hydraulic barriers may reduce the passage of fish with the heaviest infectious agent burdens, emphasizing the selective role of areas of difficult passage. Further, this work expands our knowledge of infectious agent prevalence in wild salmonids and provides insight into the relationships between infectious agents and host physiology.

7.
J Parasitol ; 87(4): 744-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11534636

RESUMO

Annual, seasonal, and interlake variation in prevalence and intensity of Ornithodiplostomum ptychocheilus (Faust) metacercariae was assessed in populations of fathead minnows (Pimephales promelas) collected from 4 lakes in north-central Alberta. Mean metacercariae intensity in young-of-the-year minnows varied extensively (5-123 metacercariae/host) among year, month, and lakes. In 2 of the lakes, prevalence always reached 100%, and mean intensity always peaked in September or October. The high spatial and annual variation in metacercarial recruitment was partly attributable to variation in host size. but variation in water depth, temperature, snail densities, and bird visitation likely also played a role. A laboratory experiment demonstrated that host and metacercariae survival was intensity-independent during a period of simulated winter. Thus, metacercariae recruited in the fall survive until the following spring.


Assuntos
Cyprinidae/parasitologia , Infecções por Trematódeos/veterinária , Alberta/epidemiologia , Animais , Cyprinidae/crescimento & desenvolvimento , Doenças dos Peixes , Água Doce , Dinâmica Populacional , Estações do Ano , Infecções por Trematódeos/mortalidade
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