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1.
The small, genetically distinct population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Port Stephens, New South Wales (NSW), is the target of the largest dolphin-watching industry in Australia and falls within the recently created Port Stephens—Great Lakes Marine Park. The effectiveness of Speed Restriction Zones (SRZs) as a management tool in this area was investigated during their second year of implementation by comparing dolphin usage and behaviour to adjacent Control Zones (CZs) of similar habitat. For this purpose, boat-based surveys and focal follows of dolphin groups were carried out in the zones between August 2008 and August 2009. Results showed that SRZs were more intensely used by dolphin-watching boats in summer. There was no change in dolphins’ behaviour and group structure in the presence of dolphin-watching boats in SRZs when compared to dolphin groups within CZs in any season. Dolphin groups including calves used SRZs less during summer. The latter may indicate a shift in area utilisation for those groups during intense boat traffic by dolphin-watching operators. CZs were more important than SRZs as foraging grounds for dolphins in summer. This indicates that SRZs as specified are not effective at minimising boating impacts and that the location of these zones should in time be revised. This is important information for management of dolphin-watching within this marine park and an example of adaptive management in progress. Moreover these results are relevant for conservation of dolphins and the management of dolphin-watching industries elsewhere, particularly new industries, where management strategies may incorporate marine protected areas including zoning plans.  相似文献   

2.
White stumpnose Rhabdosargus globiceps is the main target of the linefishery in Saldanha Bay. Increased fishing pressure over the last three decades, particularly by the recreational sector, has led to concerns regarding sustainability of the local white stumpnose stock. The fishery was exceptionally productive between 2006 and 2008, with an estimated annual catch of 141.2 tonnes (t). Only 3% of boat outings surveyed were commercial boats targeting white stumpnose, yet this sector accounted for 39.3 t (31%) of the average annual catch. The recreational boat sector accounted for most of the catch (70.0 t), and the recreational shore sector the least (31.9 t). Commercial boat catch per unit effort (CPUE; 3.7 fish angler–1 h–1) was more than 10 times that of recreational boats (0.3 fish angler–1 h–1). White stumpnose catch length-frequency differed significantly (p < 0.01) between the fishing sectors, with the commercial sector retaining larger fish (34.7 cm [SD 5.9]) than the recreational boat (33.9 cm [SD 5.9]) and shore (30.4 cm [SD 5.8]) sectors. A decline in commercial CPUE (2000–2015) of approximately 40% and a concomitant severe decline (>95%) in survey data for juvenile white stumpnose CPUE (2007–2016) indicate that the current rate of exploitation is not sustainable. Recovery of the white stumpnose stock will require a decrease in fishing mortality. Possible management regulations include sector-specific effort limitations, extending the ‘no take’ marine protected area, reducing the recreational-sector bag limit to 5 fish person–1 day–1, implementing a commercial-sector bag limit, and increasing the minimum size limit to 30 cm TL.  相似文献   

3.
橡皮艇的种类繁多、型号各异,有部队作战用的军用艇、武警防汛救援的防汛艇、专门追求速度的挂机艇、完全手动的皮划艇、体验激流乐趣的漂流艇、用于近海垂钓的钓鱼艇等。中国的橡皮艇业在近几年有着飞速的发展。文章从硬底橡皮工作艇基本特点和生产知识、概念设计目的和意义,以及概念设计对产品设计重要性等方面进行介绍,运用Solidworks软件对橡皮工作艇进行尺寸选择和结构布局设计,从而体现外观设计的人性化。通过对橡皮工作艇基本知识和主要设计理论的介绍,加强对橡皮工作艇设计方面的掌握。  相似文献   

4.
Mexico's Federal Programme of Actions for the Conservation of the Blue Whale (PACE) (Balaenoptera musculus) prioritizes whale watching (WW) research in the Loreto Bay National Park due to the increase of this activity. The aim of this study was to investigate whether whale watchers’ socioeconomic characteristics, motivations, attitudes towards whale conservation, and boat crowding influence the potential demand for WW for both first visits and the willingness to return to Loreto Bay National Park. A total of 143 structured surveys were conducted during the 2014 winter season after WW boats had returned to port. Logit econometric models in STATA were used in this analysis. The results show that the first WW experience is determined significantly by gender, nationality, whether hotel activities are a motivation for travelling, and knowledge about whales. The willingness to return depends on gender, nationality, sun and beach beauty, plans for WW before leaving home, and attitudes towards whale conservation. The results show that the reported crowding of whale mothers and calves and the willingness to accept more boats is negatively related to the willingness to return. Management recommendations are to maintain the current legislation, continue with passive observation and optimize the number of trips and tourists per boat. Differences in the demand determinants and in the type of tourists for first and repeat visitors suggest the possibility of creating different market segments. A national programme for WW that considers WW diversity and conservation initiatives would enhance sustainable wildlife tourism as part of marine policies.  相似文献   

5.
The underwater acoustic noise of five representative whale-watching boats used in the waters of west Maui was measured in order to study the effects of boat noise on humpback whales. The first set of measurements were performed on 9 and 10 March, close to the peak of the whale season. The ambient noise was relatively high with the major contribution from many chorusing humpback whales. Measurements of boat sounds were contaminated by this high ambient background noise. A second set of measurements was performed on 28 and 29 April, towards the end of the humpback whale season. In both sets of measurements, two of the boats were inflatables with outboard engines, two were larger coastal boats with twin inboard diesel engines and the fifth was a small water plane area twin hull (SWATH) ship with inter-island cruise capabilities. The inflatable boats with outboard engines produced very complex sounds with many bands of tonal-like components. The boats with inboard engines produced less intense sounds with fewer tonal bands. One-third octave band measurements of ambient noise measured on 9 March indicated a maximum sound pressure level of about 123 dB re 1 microPa at 315 Hz. The maximum sound pressure level of 127 dB at 315 Hz was measured for the SWATH ship. One of the boats with outboard engines produced sounds between 2 and 4 kHz that were about 8-10 dB greater than the level of background humpback whale sounds at the peak of the whale season. We concluded that it is unlikely that the levels of sounds produced by the boats in our study would have any grave effects on the auditory system of humpback whales.  相似文献   

6.
Being able to accurately locate and describe recreational use within marine parks is essential for their sustainable management. Given the difficulty in accessing many marine parks, as well as their large size, the surveys to obtain these much-needed data are often logistically challenging and expensive. Aerial surveys are one potential method for obtaining accurate, timely data and this paper details the design for one such survey conducted in the Ningaloo Marine Park, off the northwestern coast of Australia. Ningaloo has been nominated as a world heritage site and the fringing coral reef that forms the centrepiece of the Marine Park extends for 300 km along the coastline. The survey involved 34 temporally stratified flights conducted over a 12-month period. All vessels and people were geo-referenced and where possible, their activities were recorded, providing data that clearly illustrates dramatic expansions and contractions in recreational use. Not only does the spatial extent of use expand in the peak visitor season (April-October), the density of use correspondingly increases. High densities of recreational activity in the Park’s waters were accompanied by increased numbers of vehicles, camps, boat trailers and boats on the adjacent shoreline. Aerial surveys proved to be an effective method for rapidly obtaining recreational data with high spatial accuracy. Such a method has broad applicability to marine parks as it provides comprehensive data to benchmark existing recreational use, as well as monitor future changes in activity patterns, which are essential for the informed management that must underpin sustainability efforts.  相似文献   

7.
The Narragansett Bay in Rhode Island is a complex mosaic of human activities and environmental features and while spatial distributions of physical, chemical, and biological elements are well documented in the Bay, there are limited data on spatial distributions of human activities. In this study, human uses of coastal waters in the upper Narragansett Bay are examined using an approach for characterizing and analyzing fine scale spatial and temporal data on human activities. Shipboard transect surveys of active water activities were conducted in the upper Bay on 50 days during the summer months of 2006–2007. The composition and configuration of different vessel types (recreational motor, recreational sail, row boat, commercial fishing, industrial, service, and official) were analyzed, and the impacts of proposed changes in land use policies and wastewater treatment technologies were investigated. Results indicated that recreational boaters comprised almost two-thirds of the upper Bay's users and used over one-half of the study area. Industrial activity was concentrated near Providence where RI's main port is located, and there was an active commercial fishery in the southern portion of the study area. Conditions like increasing cloud cover, weekend days, and the July 4th holiday were related to increased recreational use, while the closure of an upper Bay beach to swimming was associated with fewer commercial fishing vessels and more official boats, recreational motor boats, and service vessels. Findings indicated that upper Bay waters near land converted from industrial zones to zones where residential housing or marinas are encouraged are likely to see a change in composition of vessels, with fewer industrial and official boats and more recreational motor boats, row boats, and service vessels. Enhanced wastewater treatment technologies and the resulting improvements in water quality are likely to make more waters in the upper Bay available to shellfish harvesting, spreading out existing fishing grounds and potential pressures on the ecosystem and on other users. By characterizing the spatial and temporal heterogeneity of human uses in the marine environment and analyzing how these uses relate to the complex human and natural systems in which they are embedded, this study and others like it can positively contribute to marine spatial planning and management efforts designed to achieve ecological, economic, and social objectives.  相似文献   

8.
本文是在对两国渔业发展情况调查研究的基础上,对比了两国渔船在性能方面的差异,分析了日本渔船的发展趋势,提出了中国渔船近期发展的方向。日本渔船改为节能型后,两国渔船的船型相近,其稳定与适航性指标亦相差不大。日本渔船的装备优于中国的渔船,平均单船功率为46.5kW/艘,中国的平均单船功率为23.03kw/艘。日本渔船的助渔设备、机电设备、制冷设备均较先进,主机推进系统多采用可变螺距螺旋浆或多级减速,中国渔船的推进方式多为定距浆,现在正推广多级减速装置。日本渔船业的发展趋势为:控制规模,提高性能,确保安全,改善适居性。我国渔船的发展方向是:减少渔船的数量,适度发展外海和远洋作业渔船,改善渔船装备,改造小型渔船,大力发展FRP渔船。  相似文献   

9.
Yachts and recreational boats have been growing in popularity throughout the world. In the United States alone they have a 2% annual growth rate. This growth has created the market for new boats built with improved hull materials and new hull forms, propulsion motors and fabrication techniques. With this growth in boat designs and technology developments, it is useful to examine the current trends in pleasure boat design. This paper addresses the development and utilization of a relational pleasure boat database BOATDSS–Boat Decision Support System. The BOATDSS database contains the data on 850 boat designs. The Decision Support System portion of the BOATDSS is organized to use this data for decision support such as a buyer shopping or a builder examining the potential of a new boat entering the present boat market. Several results from BOATDSS are presented to illustrate its use during the conception and preliminary design of recreational boats.  相似文献   

10.
Anticipating the impacts of a new policy before implementation on a complex social–ecological system is a challenging task for managers and policymakers. This paper reports on the development and use of an agent-based model (ABM) dedicated to support marine park managers in their effort to devise policies to sustainably manage whale-watching activities. The ABM, called the Marine Mammal and Maritime Traffic Simulator (3MTSim), represents the spatiotemporal dynamics of marine mammals and navigation activities in and around the Saguenay–St. Lawrence Marine Park in Canada. In the context of updating the current regulations on whale-watching in the Marine Park, 3MTSim was run to evaluate the merits of a proposed set of rules compared to the current regulations. To do so, a set of variables related to policies’ impacts on the three spheres of sustainable development, namely the impact on whales (Environment), on whale-watching companies (Economy), and tourist experience (Society) was analysed. 3MTSim's simulations highlighted that the proposed rules are expected to improve the situation regarding whale conservation and tourist experience with only marginal impact on the whale-watching industry. In the proposed regulations, one rule is expected to be very influential on whale-watching activities. This rule limits to 10 the number of whale-watching boats allowed to stand within 926 m of any boat in observation mode. Assuming efficient law enforcement, 3MTSim predicts a significant decrease in overall boat concentration around whales in the Marine Park, which is one of the management objectives benefiting both whales and tourists. Interestingly, 3MTSim reveals that this rule could indirectly force some boats to observe second-choice whales present in higher abundance rather than some more attractive species scarcer in the region. This highlights the following management tradeoffs: Reducing boat exposure for the humpback whale and endangered blue whale is likely to increase it for the more abundant fin whale listed as of special concern (Canada's Species at Risk Act) and minke whale. This work demonstrates the utility of ABMs to support policy analysis in the context of sustainable management in a Marine Park. ABMs developed in close relationship with end-users are unarguably a tool of choice to manage complex social–ecological systems since they provide insight into phenomena hard or impossible to measure in the real system. Despite the labour intensive nature of their implementation, this investment is worth the effort.  相似文献   

11.
Over the last several years, significant regulatory changes related to Pacific halibut Hippoglossus stenolepis have occurred in the for-hire recreational charter boat fishing sector in Alaska. In addition to limited entry restrictions and adoption of a catch sharing plan that provides a formal means of determining allocation between the commercial and charter boat fishing sectors, more restrictive harvest regulations were placed on anglers fishing from charter boats. This article provides insights into how the value anglers place on charter boat fishing is affected by these regulations, principally bag and size limits. Such information is helpful in assessing the trade-offs in economic benefits associated with different regulatory tools used to manage angler harvest levels. Stated preference choice experiment data from a 2012 survey are analyzed using a panel rank-ordered mixed logit model to estimate the economic value, or willingness to pay (WTP), non-resident anglers place on saltwater charter boat fishing trips in Alaska and to assess how changes in characteristics of fishing trips, particularly harvest restrictions related to Pacific halibut, affect this value. The model specification accounts for a wide array of size and bag limit restrictions that have been recently implemented or are under consideration by Pacific halibut fishery managers. The results indicate that very strict harvest restrictions have the effect of driving WTP to zero, while allowing at least one (potentially) large fish to be caught is valuable to anglers. The results also suggest that WTP for fishing trips with bag limits that allow two or more fish to be harvested with no size restrictions on the first fish harvested are not statistically different from the value for trips for larger bag limits or for the case where all the fish in the limit can be any size. This suggests that fishery managers can restrict the size of the second fish in a two-fish bag limit and still maintain economic values for fishing trips.  相似文献   

12.
Taiwanese fishing boats have been hijacked many times this year. Trouble at sea can usually be attributed to communication problems, inappropriate management and an unfair salary system. The majority of boats hijacked are high sea (long-line) fishing boats. Although fishery authorities ask the fishing boats to set up vessel monitoring systems (VMSs), this precaution has not been sufficient. There is a further need for improved management by the fishing boat owner and for an improved employment policy for seamen. The issue of maritime security is not new, but it remains a major concern and continues to be a threat to Taiwan and other countries. To date, there have been many cases of hijacking in the South China Sea. This paper analyzes the reasons for the hijackings and provides potential strategies to prevent future incidents.  相似文献   

13.
The Oceania population of humpback whales (Megaptera novaeangliae) using Tongan waters is a listed Endangered subpopulation that supports a large swim-with whale industry focussed primarily on mothers and calves. This raises concerns about the industry's potential to impact on the subpopulation's breeding success and recovery. This study investigated whether whales responded differently to approaches by swimmers from boats than to boat approaches alone and whether different types of swimming (quiet approach, loud splashing or diving following a quiet approach) induced different avoidance responses. An avoidance response was defined as whales moving away from boats or swimmers and the strength of the response was defined by how far the whales moved away and whether there was an increase in surface activity. Animals responded more quickly to a loud splashing approach than to quiet approaches. There were no significant differences in measures relating to the strength of the response caused by swim type, however closer approaches by a boat did significantly increase the level of whale activity. These results suggest that managing swimmer behaviour around whales, particularly ensuring quiet approaches, will contribute to the ability of the industry to minimise disturbance of the animals and support the industry's sustainability.  相似文献   

14.
Ecosystem-based management is more successful when a great diversity of stakeholders is engaged early in a decision-making process. Implementation of the California Marine Life Protection Act (MLPA) has been stakeholder-based, coordinating the participation of a wide range of people including divers, fishermen, conservationists, local officials, business owners and coastal residents. Although commercial and recreational fishermen have actively participated throughout the MLPA implementation process, and research related to California’s sport and commercial fisheries has been integrated into the process, pier and shore anglers have been relatively unengaged as stakeholders. This study was completed to generate information about pier angler understanding and sentiment towards marine protected areas (MPAs), as well as to educate anglers on the MLPA implementation process in southern California and inform them on involvement opportunities. Of the 3030 pier anglers surveyed over 12 months, 78% only fish for subsistence from piers and from shore (never from boats); 84.6% are of non-White/Euro-American ethnicity and speak English as a second language; and 82% indicated that they were supportive of establishing a strong network of MPAs in southern California, specifically fully-protective no-take marine reserves. This study is an example of an alternative and customized method of outreach designed to reach a unique and previously unengaged stakeholder group, which stands to be affected by the implementation of the MLPA in California. Engaging such non-traditional stakeholders in public policy may be critical for decision makers to gauge all views from those standing to be affected by a policy—not just the views of those that regularly attend policy meetings—and for the ultimate success of policy implementation and community support.  相似文献   

15.
This study examined the perceptions of fishers from two fishing communities with differing use histories and involvement in the long-standing (16 yr) multiple use Mafia Island marine protected area (MIMP), Tanzania. A randomly distributed questionnaire indicated that 94% of fishers believed that without the MIMP, there would be overfishing, dynamite use, destroyed habitats, and few fish. Fishers were more positive about core zones (no-take fishery closures) than general use zones (areas allowing selective fishing) as a consequence of increases in fishing pressure. Those that reported increased catches and sizes of fish since the creation of the MIMP were more likely to agree with present zone locations and more positive in general about fisheries and conservation planning. Most thought that fish size and gear restrictions were preferable to permanent closures. Perceptions differed among communities and gear users. Community and gear type explained 46% of the variance in responses about the perception that fisheries and conservation are compatible goals. Somewhat surprisingly, these effects were more important than catch increases or involvement in MIMP-related activities. The differences in perception between communities may be partly attributed to different fishing histories. Multiple-use zoning provides a means to identify and resolve conflicts and achieve what are likely universal objectives for fisheries sustainability and conservation.  相似文献   

16.
玻璃钢渔船有很多优异的性能,因而有逐渐取代本质渔船的趋势,为推进玻璃钢渔船的产业化进程,作者查痒了大量国内外有关资料,并进行了玻璃钢渔船船体材料切片的灼烧试验,最终提出了我国玻璃钢渔船船体材料切片的灼烧试验的试验规程,以供我国今后制定玻璃钢渔船材料试验标准作参考。  相似文献   

17.
A new sledge net system using propulsion vehicles has been developed to sample more efficiently the demersal juveniles of marine organisms. A net attached to a sledge maneuvered by a SCUBA diver who uses operating switches on a steering handle to adjust the altitude of the sledge and the position of the tickler chains to ensure that the footcloth of the mouth of the net remains in constant contact with the bottom surface. Video camera, flow meter, compass, and dive computers are positioned on the sledge net in the view of the diver. Given that the system can attain speeds of 70 cm s−1, the net can be employed to capture highly mobile fish. Unlike most boat-based net sampling methods, the use of propulsion vehicles means that there are no sound or vibration disturbances due to the boat and tow ropes typically used to maneuver these types of sampling nets. Marine fauna was collected at monthly intervals over a two-year period in a sampling area along the southern coast of Hokkaido, Japan. A total of 2641 specimens comprising 61 species and including five species which were the first records for the region were collected. These findings suggest that the new sledge net system employing propulsion vehicles was effective for sampling demersal juveniles, particularly in situations where sledge nets towed by boats or push nets cannot be deployed.  相似文献   

18.
The European Commission has repeatedly requested its Member States to fully implement one of the world's oldest nature legislation laws, the Birds Directive, by designating Special Protection Areas (SPAs) in the marine environment. The current work analyses the spatial coverage offered by the SPA network to the 82 species of seabirds that occur in EU waters, and compare it to that of Important Bird and Biodiversity Areas (IBAs), as defined by BirdLife International. Marine SPAs represent 3.9% of the EU's marine area, while the IBA network represents 4.4%. On average, only 0.05% of the EU marine area is protected, and there are enormous regional differences. On average, SPAs and IBAs both cover 16.0% of the breeding distribution range of seabird species, but only1.4% of their non-breeding distribution range. SPAs cover more than 50% of the breeding range of only one seabird family, Procellariidae, and both SPA and IBA networks offer greater coverage to threatened species than to non-threatened ones. The year when Member States were legally obliged (2008 onwards) to declare their marine SPA networks is not significantly related to their network size, and that those species subjected to tracking studies or have well known breeding colonies benefit from higher coverage. Methodological challenges that were once posed to implement the Birds Directive at sea are largely overcome, and political will is the main driver for identifying, designating and managing a complete network of marine SPAs in the EU.  相似文献   

19.
Marine protected areas (MPAs) have proliferated globally in the past three decades. However, inadequate funding often prevents these management regimes from fulfilling their missions. Managers have become increasingly aware that successful protection of marine ecosystems is dependent not only upon an understanding of their biological and physical processes, but also their associated social and economic aspects. Unfortunately, economic values associated with MPAs and the natural resources they protect are rarely considered in decision-making and policy development. This study addresses this information gap by examining scuba divers’ willingness to pay for access to quality recreational sites in the Bonaire National Marine Park, Bonaire, Netherlands Antilles. The findings indicate that the US$10 annual diver user fee in effect at the time of the study could be increased substantially without a significant adverse effect on island tourism. Depending on question format, mean willingness to pay for annual access ranged from US$61 to US$134 (2002$). All model specifications support the conclusion that doubling the US$10 user fee would have virtually no impact on visitation rates. The increased revenue generated from this sustainable financing mechanism is more than sufficient to fund both current and enhanced marine park operations.  相似文献   

20.
Recent international policy developments require states to conserve at least 10% of coastal and marine areas by creating effectively managed and ecologically coherent networks of protected areas in the marine environment. In the framework of the PANACHE project, the current status of designation, management and monitoring of the network of marine protected areas (MPAs) of an important environmental, social and economic marine area: the English Channel (the Channel) was examined. Currently 224 MPAs exist belonging to 12 different designation categories and covering 17 440 km2, or approximately 20.3% of the project area in the Channel. International protection targets in the marine environment are thus met at this regional scale, although the individual contributions of the UK and France are considerably different, with French MPAs accounting for nearly 80% of the total area protected. Differences between countries are also found regarding MPA designation categories (11 in France, 6 in the UK, 1 in the Channel Islands) and management structures (with more actors involved in the UK) and approach, whereas the monitoring techniques used are similar, although more standardised in the UK. Pending challenges include greater within-country and cross-country MPA designation, monitoring and management simplicity, integration and coordination as well as the assessment of management effectiveness and ecological coherence of the Channel network of MPAs.  相似文献   

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