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1.
Daniel Pauly 《Reviews in Fish Biology and Fisheries》1998,8(3):307-334
The extension into tropical areas of Beverton and Holt's yield per recruit approach for stock assessment represents a straightforward case of normal science, the common Kuhnian counterpart to his much rarer paradigm shifts. It is shown that the normal science which, in recent decades, has led to new methods for estimating growth, mortality and other statistics required for yield per recruit analyses in data-sparse environments, has not only enriched fisheries science and aquatic biology as a whole, but has also contributed to identify the limitations of the single-species research programme originally defined by Beverton and Holt. The most likely prospect for that programme, in the tropics and elsewhere, is to become a component of the multispecies, or rather ecosystem approach that is emerging, and to which Beverton and Holt will have contributed many of the concepts, and much of the rigour. 相似文献
2.
More than just a Long Paddock: Fostering native vegetation recovery in Riverina Travelling Stock Routes and Reserves
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Travelling Stock Reserves provide the most significant networks of natural habitat in the New South Wales Riverina. Substantial biodiversity gains at two sites over 10 years inspired similar works on more than 200 reserves with high levels of demonstrable change occurring. 相似文献
3.
Out-migration of Tagged Fishes from Marine Reef National Parks to Fisheries in Coastal Kenya 总被引:1,自引:0,他引:1
We evaluated movements of 25 species of coral reef fishes from Malindi and Watamu Marine National Parks (created 1968) in coastal Kenya from February 2001 to March 2002. Only three species, the commercially important whitespotted rabbitfish, Siganus sutor, the sky emperor (SEM), Lethrinus mahsena and the trumpet emperor, L. miniatus, exhibited consistent movements from the parks. At Malindi Park, more fishes were recaptured by fishermen off a fringing reef than off a patch reef. The rabbitfish had a higher monthly spillover rate from the fringing reef than from the patch reef. In contrast, the SEM had low monthly spillover rates from both reefs. The rabbitfish moved greater distances off the fringing reef than off the patch reef. At Watamu Park, the SEM, L. miniatus and the gold-spotted sweetlips, Gaterin flavomaculatus, had equal monthly spillover rates. In contrast, the rabbitfish had a lower monthly rate. The emperors showed no difference in net distance moved from the park boundary, however, L. miniatus traveled significantly longer distances than did the SEM. Distances between release and capture sites were either random (SEM), increasing (L. miniatus), or decreasing (rabbitfish) with respect to time at liberty. 相似文献
4.
A total of 76 reef fish species from 31 families was collected at two coral reef sites, one in a marine reserve and the other in an adjacent fished area of the Soufrière Marine Management Area (SMMA) in St. Lucia. Five families (Scaridae, Pomacentridae, Synodontidae, Apogonidae and Blennidae) dominated the collections at both sites while species of high commercial value were rare. Monthly patterns of larval supply differed among selected species, but overall trends were similar between the two sites for most species. However, despite the geographical proximity of the two sites, the fished area received a consistently higher abundance and diversity of larvae than the marine reserve throughout the study period. Patterns in larval supply generally were reflected in the settlement patterns of Stegastes partitus. Results suggest that local-scale variation in hydrodynamic and or biological features is influencing the arrival and hence settlement of larvae at the reef. 相似文献
5.
Johansson ML Banks MA Glunt KD Hassel-Finnegan HM Buonaccorsi VP 《Molecular ecology》2008,17(13):3051-3061
The copper rockfish is a benthic, nonmigratory, temperate rocky reef marine species with pelagic larvae and juveniles. A previous range-wide study of the population-genetic structure of copper rockfish revealed a pattern consistent with isolation-by-distance. This could arise from an intrinsically limited dispersal capability in the species or from regularly-spaced extrinsic barriers that restrict gene flow (offshore jets that advect larvae offshore and/or habitat patchiness). Tissue samples were collected along the West Coast of the contiguous USA between Neah Bay, WA and San Diego, CA, with dense sampling along Oregon. At the whole-coast scale (approximately 2200 km), significant population subdivision (F(ST) = 0.0042), and a significant correlation between genetic and geographical distance were observed based on 11 microsatellite DNA loci. Population divergence was also significant among Oregon collections (approximately 450 km, F(ST) = 0.001). Hierarchical amova identified a weak but significant 130-km habitat break as a possible barrier to gene flow within Oregon, across which we estimated that dispersal (N(e)m) is half that of the coast-wide average. However, individual-based Bayesian analyses failed to identify more than a single population along the Oregon coast. In addition, no correlation between pairwise population genetic and geographical distances was detected at this scale. The offshore jet at Cape Blanco was not a significant barrier to gene flow in this species. These findings are consistent with low larval dispersal distances calculated in previous studies on this species, support a mesoscale dispersal model, and highlight the importance of continuity of habitat and adult population size in maintaining gene flow. 相似文献
6.
Marine reserves and optimal harvesting 总被引:6,自引:1,他引:6
Michael G. Neubert 《Ecology letters》2003,6(9):843-849
Advocates of no‐take marine reserves emphasize their conservation benefits. Critics counter that reserves would decrease fisheries yield. Analysis of a spatially explicit harvesting model, however, shows that no‐take marine reserves are always part of an optimal harvest designed to maximize yield. The optimal harvest generates a spatial source–sink structure with source populations placed in reserves. The sizes and locations of the optimal reserves depend on a dimensionless length parameter. For small values of this parameter, the maximum yield is obtained by placing a large reserve in the centre of the habitat. For large values of this parameter, the optimal harvesting strategy is a spatial ‘chattering control’ with infinite sequences of reserves alternating with areas of intense fishing. Such a chattering strategy would be impossible to actually implement, but in these cases an approximate yet practicable policy, utilizing a small number of reserves, can be constructed. 相似文献
7.
Understanding patterns of connectivity among marine fish populations with demersal adults and pelagic larvae is critical for
effective conservation of west coast rockfishes. The brown rockfish (Sebastes auriculatus) occurs in nearshore habitat and is common from northern Baja California, Mexico to northern California, rare off the outer
coast of Oregon and Washington and again common in the inland waters of Puget Sound, Washington. Here we examine patterns
of microsatellite DNA diversity from throughout the species’ range as an indirect measure of long-term trends in larval dispersal.
Genetic divergence was large and highly significant over all populations (F
ST=0.056, P<0.0001), and was significantly correlated with geographic distance when considering coastal populations. The best estimates
of mean coastal dispersal distance were on the order of 10 km or less per generation. Diversity was relatively low in the
Puget Sound, suggesting that Puget Sound rockfish populations experienced a post-glacial founder effect followed by genetic
isolation and low effective population size. Puget Sound individuals appeared to have recent mixed ancestry as a result of
introgression with S. maliger and S. caurinus. Genetic isolation of Puget Sound fish provides a basis for consideration as a Distinct Population Segment (DPS) under the
provisions of the Endangered Species Act. We recommend that coastal brown rockfish fisheries be managed at regional rather
than coast-wide scales, and that design of marine reserve networks considers the surprisingly low realized dispersal distance
of some species with high dispersal potential. 相似文献
8.
A recent study ( White et al. 2008 ) claimed that fishery profits will often be higher with management that employs no‐take marine reserves than conventional fisheries management alone. However, this conclusion was based on the erroneous assumption that all landed fish have equal value regardless of size, and questionable assumptions regarding density‐dependence. Examination of an age‐structured version of the White et al. (2008) model demonstrates that their results are not robust to these assumptions. Models with more realistic assumptions generally do not indicate increased fishery yield or profits from marine reserves except for overfished stocks. 相似文献
9.
Highly protected marine reserves are areas of the sea in which human disturbances are minimised so that the full natural biological
diversity is maintained or, more often, allowed to recover to a more natural state. Europe has very few marine reserves;
they are very small and almost all are in the Mediterranean. There are at present no official plans to create effective systems
of marine reserves. Europe has many so-called Marine Protected Areas (MPAs). These are marine areas with some extra regulations
or planning procedures. MPAs aim to make human activities more efficient and more sustainable. MPAs are user-orientated, knowledge-based,
locality-dependent, problem-solving extensions of standard marine planning and management. Marine reserves are quite different.
All extractive and potentially disturbing human activities are prohibited. The burden of proof is reversed; no evidence of
damage or danger to particular species or habitats is required; all marine life is protected on principle. The concept of
marine reserves is simple and practical, but because it is new, different and additional to existing marine management, the
idea is seen by many as revolutionary. Basic biological principles and practical experience in many countries make it clear
that marine reserves are important to science and education, essential for conservation and useful in resource management.
These features apply in all regions and ecosystems. They are independent of climate, biogeography, current human activities
and the present management. Representative and viable systems of marine reserves are needed in all regions. Fishing and other
human disturbances have been widespread and intensive for so long that it is very difficult to predict the stages of recovery
that occur in marine reserves. Furthermore, while some features change rapidly (e.g. numbers of previously targeted species),
recovery continues for a long time (e.g. fourth- and fifth-order trophic and structural changes after >25 years). None of
this alters the fact that, in scientific terms, marine reserves are controls not manipulations. Such controls are required
if scientists are to understand the intrinsic processes and obtain data that are not confounded by human activities (e.g.
separating natural variation from fishing effects). No significant progress will be made to establish marine reserves in
Europe until scientists speak out strongly and clearly on the issue. We consider it is part of our professional duty as marine
biologists to state publicly and frequently the need for a representative, replicated, networked and sustainable system of
highly protected marine reserves. We doubt if our grandchildren will accept any excuses if we fail.
Guest editors: J. Davenport, G. Burnell, T. Cross, M. Emmerson, R. McAllen, R. Ramsay & E. Rogan
Challenges to Marine Ecosystems 相似文献
10.
Cermeño P 《Proceedings. Biological sciences / The Royal Society》2012,279(1728):474-479
In the geological past, changes in climate and tectonic activity are thought to have spurred the tempo of evolutionary change among major taxonomic groups of plants and animals. However, the extent to which these historical contingencies increased the risk of extinction of microbial plankton species remains largely unknown. Here, I analyse fossil records of marine planktonic diatoms and calcareous nannoplankton over the past 65 million years from the world oceans and show that the probability of species' extinction is not correlated with secular changes in climatic instability. Further supporting these results, analyses of genera survivorship curves based on fossil data concurred with the predictions of a birth-death model that simulates the extinction of genera through time assuming stochastically constant rates of speciation and extinction. However, my results also show that these marine microbes responded to exceptional climatic contingencies in a manner that appears to have promoted net diversification. These results highlight the ability of marine planktonic microbes to survive climatic instabilities in the geological past, and point to different mechanisms underlying the processes of speciation and extinction in these micro-organisms. 相似文献
11.
我们从南海海底沉积环境分离了一株放线菌SCSIO1635,经16S rDNA的序列分析将该株菌鉴定为链霉菌属。我们从该菌的发酵液中分离得到了4个化合物,经质谱和核磁共振波谱解析,确定为抗霉素类化合物:异构体antimycin A1a和A1b(1)、deisovalerylblastmycin(2)、kitamycin A(3)和antimycin A9(4)。 相似文献
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14.
On the fraction of habitat allocated to marine reserves 总被引:1,自引:0,他引:1
M. Mangel 《Ecology letters》2000,3(1):15-22
The case for marine reserves is strengthening, and both deterministic and stochastic calculations show that fisheries management using reserves may achieve harvests comparable with management without reserves. Thus, depending upon the metric used, reserves need not disadvantage harvest. Reserves provide a buffer that increases the chances of sustainability of the stock, and thus the fishery. In this paper, I develop methods (deterministic and stochastic) that allow one to determine how much habitat needs to be set aside as reserve, once societal decisions concerning the goals of reserves are made. The answer to the question: "how much habitat needs to be allocated to reserves" is not a simple single number. Rather, it is a procedure that can be employed once biological, operational and social information are provided. The methods also apply to reserves used to aid stock recovery. 相似文献
15.
The histories of management of the Sumilon and Apo marine reserves in the Philippines provide a stark contrast. Both began
with marine conservation and education programs at the community level, initiated by the Marine Laboratory of Silliman University
in 1973 at Sumilon, and in 1976 at Apo. At both islands community support for the “no take” reserve concept evolved gradually,
via perceived benefits of increased local fish yields and income from tourism. However, Sumilon reserve has been fished down
twice (in 1984,1992), and was still being fished in December 1998. Apo reserve has been protected from fishing successfully
for 16 y (1982–1998). The management histories of these two marine reserves are the longest and most detailed available for
coral reefs. Scientific data spanning 1976–1993 for Sumilon and 1980–1993 for Apo have provided some of the best available
evidence of the utility of such reserves as management tools in coral reef fisheries. At Sumilon, collapse of reserve protection
in 1984, after 9.5 y of restrictions on fishing, led to significant declines in reef fisheries yields in areas adjacent to
the reserve. At Apo, continuous protection from 1982 to 1993 has led to consistent build up of fish in the reserve and some
evidence that local fish yields have increased. The unique time series of scientific data obtained from Sumilon and Apo islands
are the result of their distinct management histories. The greater success of management at Apo was due to community support
for the reserve concept being actively maintained for the past 16 y. Socio-political factors caused the level of community
support for the Sumilon reserve to wax and wane over this period. Both case histories have had a profound effect on marine
resource management in the Philippines. As marine reserve models they had substantial influence on the design of the National
Integrated Protected Area System (NIPAS). Policy now encourages co-management between the National government and local communities,
with a strong emphasis on decentralization of decision making and recognition of local territorial use rights in fisheries.
Accepted: 14 May 1999 相似文献
16.
The aim of this article is to shed some light on an appropriate criterion for assessing risk/consequences in the maritime transport industry, with respect to the view of society. A major problem is how to derive credible and exploitable data from/for the society and try to understand how it reacts to accidents (i.e., misfortunes) of different scale. Therefore the set problem is the assessment of the maximum risk that the society will tolerate for a specific activity. In the shipping industry, the problem is complicated due to the fact that a single maritime incident can produce consequences of different types, for example, both human losses and oil spillage can result from the same accident. In effect, this article focuses on the integration of different consequences of an accident into one metric that will allow the direct and exploitable comparison of accidents of different scales and characteristics and therefore present a clearer picture of the risks that the society takes and/or is willing to accept. Hence, a new framework for marine risk assessment is introduced, which is able to project the risk that a group of people (i.e., the society) can accept for accidents of different size or type. 相似文献
17.
C. Wiencke J. Rahmel U. Karsten G. Weykam G. O. Kirst 《Plant biology (Stuttgart, Germany)》1993,106(1):78-87
The photosynthetic performance of macroalgae isolated in Antarctica was studied in the laboratory. Species investigated were the brown algae Himantothallus grandifolius, Desmarestia anceps, Ascoseira mirabilis, the red algae Palmaria decipiens, Iridaea cordata, Gigartina skottsbergii, and the green algae Enteromorpha bulbosa, Acrosiphonia arcta, Ulothrix subflaccida and U. implexa. Unialgal cultures of the brown and red algae were maintained at 0°C, the green algae were cultivated at 10°C. IK values were between 18 and 53 μmol m?2 s?1 characteristic or low light adapted algae. Only the two Ulothrix species showed higher IK values between 70 and 74 μmol m?2 s?1. Photosynthesis compensated dark respiration at very low photon fluence rates between 1.6 and 10.6 μmol m?2 s?1. Values of α were high: between 0.4 and 1.1 μmol O2 g?1 FW h?1 (μmol m?2 s?1)?1 in the brown and red algae and between 2.1 and 4.9 μmol O2 g?1 FW h?1 (μmol m?2 s?1)?1 in the green algal species. At 0°C Pmax values of the brown and red algae ranged from 6.8 to 19.1 μmol O2 g?1 FW h?1 and were similarly high or higher than those of comparable Arctic-cold temperate species. Optimum temperatures for photosynthesis were 5 to 10°C in A. mirabilis, 10°C in H. grandifolius, 15°C in G. skottsbergii and 20°C or higher in D. anceps and I. cordata. P: R ratios strongly decreased in most brown and red algae with increasing temperatures due to different Q10 values for photosynthesis (1.4 to 2.5) and dark respiration (2.5 to 4.1). These features indicate considerable physiological adaptation to the prevailing low light conditions and temperatures of Antarctic waters. In this respect the lower depth distribution limits and the northern distribution boundaries of these species partly depend on the physiological properties described here. 相似文献
18.
The taxonomic distribution, structure, and biological activity of halogenated alkaloids isolated from marine microorganisms and sponges are reviewed. The structures of nearly 140 natural bromo- and iodo-containing alkaloids are shown. 相似文献
19.
Dependence of sustainability on the configuration of marine reserves and larval dispersal distance 总被引:7,自引:0,他引:7
Marine reserves hold promise for maintaining biodiversity and sustainable fishery management, but studies supporting them have not addressed a crucial aspect of sustainability: the reduction in viability of populations with planktonic larvae dispersing along a coastal habitat with noncontiguous marine reserves. We show how sustainability depends on the fraction of natural larval settlement (FNLS) remaining after reserves are implemented, which in turn depends on reserve configuration and larval dispersal distance. Sustainability requires FNLS to be greater than an empir-ically determined minimum. Maintaining an adequate value for all species requires either a large, unlikely fraction (> 35%) of coastline in reserves, or reserves that are larger than the mean larval dispersal distance of the target species. FNLS is greater for species dispersing shorter distances, which implies reserves can lead to: (1) changes in community composition and (2) genetic selection for shorter dispersal distance. Dependence of sustainability on dispersal distance is a new source of uncertainty. 相似文献
20.
A diverse fouling community discovered encrusting a barge intended for deployment at subantarctic Macquarie Island is described and its role as a transport vector for non-indigenous marine organisms is discussed. The barge proved to be a potential vector capable of transporting entire epi-bethic communities, 20 species in total, from a temperate estuarine system (Derwent River, Tasmania, Australia) into the subantarctic. For one invasive amphipod species Monocorophium acherusicum, over 136000 individuals including ovigerous females were calculated to be associated with the barge fouling community. Although distinct differences exist between the thermal ranges of Macquarie Island and the Bruny bioregion of Tasmania, a hazard assessment based on the Gower similarity coefficient suggested sufficient similarity between the two environments to allow for survival of transported organisms for eight months of the year. Several invasive species are able to survive the thermal conditions of the subantarctic irrespective of the time of year. This study identifies the need for effective quarantine measures aimed at identifying and managing marine biosecurity hazards in association with human activities in high latitude regions. 相似文献