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- 1. Current selection of marine protected areas in South Africa is based on objective criteria including biogeographic representation and habitat heterogeneity. This paper specifically examines rocky shores on the west coast of South Africa to determine whether they are divisible into discrete ‘habitats’ that need independent conservation.
- 2. Seventeen rocky shores spanning the full spectrum of wave exposure were compared in terms of maximum wave forces, biomass, species richness and diversity among zones and sites. Three biotic assemblages were identified, characterizing sheltered, semi‐exposed to exposed, and very exposed habitats. Differences among these were clear‐cut low on the shore but disappeared at the top of the shore where wave action was attenuated and desiccation uniformly intense.
- 3. The recognition of three discrete biologically‐defined habitats means that rocky shores cannot be regarded as a uniform habitat for conservation purposes. All three components need protection if the full spectrum of rocky‐shore communities is to be conserved.
- 4. It is argued that this approach allows habitats to be defined in an objective manner, and that once this has been done, habitat heterogeneity constitutes a better measure of conservation value of an area than a ‘hotspot’ approach based on species richness and endemism.
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The intertidal cockle Austrovenus stutchburyi, also known as tuangi or littleneck clam, is endemic to New Zealand, where it commonly occurs in sheltered sandflats and
estuaries. While it is still abundant in some places, recreational collecting and habitat change have resulted in the losses
of shellfish beds. This paper reviews the current status of cockle beds in New Zealand and outlines some of the methods that
are being used to try to re-establish them. Cockle populations differ both within and between locations, and recent research
suggests that this is often site-specific and correlated with sediment properties, salinity and contamination levels. The
role of Customary Fishing Regulations and the management of Maori Marine Reserves in promoting cockles as a sustainable shellfishery
is discussed, together with the role of closures. The transfer of adult stock may be the most promising technique for restoration.
There is, however, a need to identify the potential risks and choose the sites carefully to ensure that shellfish are sustainable
and that they improve ecosystem function. 相似文献
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- This paper describes how a series of papers published in Aquatic Conservation have had a clear impact on the conservation process run at Rapa Nui by the Chilean Government and the Rapanui community.
- Exploratory expeditions set the scientific basis for the creation of Rapa Nui Multiple Use Marine Protected Area.
- Past conservation initiatives lacked proper participative processes and were strongly resisted by the local communities.
- Science transfer through capacity building was key for a local transformation towards embracing marine conservation objectives.
- Publications showed the importance of participation, a good balance between political will and a local wish for protection of the sea, and the incorporation of a local worldview, for a successful conservation process.
- Strong differences between the socio‐ecological systems in mainland Chile and that in Rapa Nui were recognized and helped to build a new conservation strategy for Rapa Nui between the Chilean Government and Rapanui community.
- International experience exchanges also helped to develop the conservation process in Rapa Nui, and recent ecological studies will help future Marine Protected Area implementation.
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Paolo Guidetti Piero Addis Fabrizio Atzori Simona Bussotti Antonio Cal Alessandro Cau Jean‐Michel Culioli Giuseppe De Lucia Antonio Di Franco Manfredi Di Lorenzo Maria Cristina Follesa Vittorio Gazale Giorgio Massaro Francesco Mura Augusto Navone David Pala Pier Augusto Panzalis Antonio Pusceddu Alberto Ruiu Angelo Cau 《水产资源保护:海洋与淡水生态系统》2019,29(4):537-545
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Takuzo Abe Toshihiro Wada Masato Aritaki Nagaaki Sato Takashi Minami 《Fisheries Science》2013,79(5):767-777
This report first describes the morphological and habitat characteristics of larval and juvenile Roughscale Sole Clidoderma asperrimum. Five metamorphosing larvae (22.1–31.7 mm standard length, SL) and 12 juveniles (23.7–46.4 mm SL) were collected from two locations in coastal waters of northeastern Japan, Shizugawa Bay (rocky habitats, 6–12 m depth) and Iwaki (sandy habitats, 10–50 m depth), respectively, using a hand net while SCUBA diving and a small trawl net during May–August in 2008 and 2010. Underwater observation in Shizugawa Bay revealed that metamorphosing larvae and juveniles that had settled on rocks or stones showed transparent and variegated body coloration, which is cryptic to a rocky habitat. Juveniles in Iwaki showed monotonic coloration. The settlement would occur during metamorphosis because the same larva observed on a stone subsequently swam with a left-lateralized body posture. The larval morphology was characterized by a dense covering of fine spines on the whole body surface. Spines on the ocular side developed steadily, gradually forming bony tubercles with growth, whereas those on the blind side regressed with development and finally disappeared in metamorphosed juveniles. Our results indicate that Roughscale Sole can settle and adapt to rocky and sandy habitats in coastal waters with wide depth range. 相似文献
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Shiang‐Lin Huang Haiping Wu Xianyan Wang Chongwei Peng Chun‐Chieh Wang 《水产资源保护:海洋与淡水生态系统》2020,30(9):1775-1782
- Protecting critical habitats of the Indo‐Pacific humpback dolphin, Sousa chinensis, is a hot topic of discussion for marine biodiversity conservation in China and many Southeast Asian countries. In practice, sound habitat protection action (HPA) planning often suffers from information gaps in macroscopic habitat configurations and changes in the habitat conditions of humpback dolphins.
- Recent publications in the journal Aquatic Conservation: Marine and Freshwater Ecosystems (AQC) have served to advance humpback dolphin conservation in Chinese waters by resolving such habitat configurations and indicating significant changes in distribution patterns and habitat characteristics under intense coastal anthropogenic activity.
- We highlight an integrative research framework to investigate habitat configuration and long‐term habitat changes when planning a holistic HPA programme for humpback dolphins. When constructing habitat configuration baselines, field surveys should be designed and conducted in a systematic manner to ensure survey efforts cover diverse environments equally, in either a spatially stratified or gridded pattern, to minimize potential spatial sampling biases. Long‐term habitat changes can be revealed by comparing satellite images from different decades. Changes in habitat preferences and habitat characteristics can be explored through questionnaire surveys on local ecological knowledge, associating historical occurrences with coastline features and projecting historical habitat configuration by species distribution modelling exercises.
- A lack of good communication and sharing of information between research and management sectors can still be an obstacle to the implementation of sound conservation practices, however, even though there is robust scientific evidence to fill knowledge gaps in distribution and habitat baselines. We have addressed the need to establish a mechanism to improve and streamline information sharing between research teams, management sectors, and stakeholder groups.
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- 1. The identification and protection of known breeding grounds is a high priority for the conservation of marine biodiversity. Here, we examine the intertidal habitats used by marine gastropods for the deposition of benthic egg masses along a wave‐exposed coastline in New South Wales, Australia.
- 2. A total of 200 surveys were conducted on 13 intertidal reefs. The egg masses of 46 species were identified, with a further eight distinct types recorded but remaining unidentified. Over half of the gastropods were found to deposit egg masses exclusively on the underside of boulders. Other intertidal substrata used for gastropod egg mass deposition included vertical and horizontal exposed rock surfaces, algal fronds and sand. Only eight species were found to attach their egg masses to more than one type of substratum.
- 3. Twelve reefs were classified into three categories according to exposure to wave action and habitat diversity. The mean number of species found depositing egg masses was compared using a standard eight surveys from each site. Sub‐maximally wave‐exposed reefs with maximal habitat diversity were found to support a significantly higher species richness of gastropod egg masses, compared with maximally wave‐exposed reefs with either maximal or sub‐maximal habitat diversity (p=0.000).
- 4. Gastropods that deposit egg masses on the underside of boulders were more likely to be found on sub‐maximally wave‐exposed reefs, whereas species that deposit egg masses in all other microhabitats were equally likely to be found breeding on sub‐maximally or maximally exposed reefs.
- 5. Gastropods with pelagic larvae tended to occur at a greater number of sites than those that hatch post‐metamorphosis. A significant difference was found between species grouped according to these two developmental modes for the mean number of sites at which egg masses were recorded (p=0.008).
- 6. Variation in the species richness of gastropods found depositing egg masses on different intertidal reefs appears to be influenced by the availability of suitable boulders and exposure to wave action. These factors should be taken into consideration during the selection of locations for intertidal protected areas.
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1. This paper describes the use of multivariate analytical techniques as an aid to classifying and assessing the nature conservation value of rocky intertidal communities round the Northern Ireland coastline. 2. Semiquantitative species abundance data from 128 rocky shore transects distributed round the coastline were subject to multivariate analysis in order to formulate a classification scheme for shore communities. Several different techniques were used on the grounds that a robust classification scheme should not be dependent upon the details of statistical methodology. Cluster analysis (three strategies) and TWINSPAN were used to produce hierarchical classification schemes, and ordination was used to assess the validity of suggested community boundaries. 3. The resulting classification scheme of rocky shore communities is presented and discussed in terms of the six scientific/ecological criteria which Mitchell (1987) identified for the comparative evaluation of marine habitats and communities for nature conservation purposes. 相似文献
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1. The effect of habitat fragmentation was investigated in two adjacent, yet separate, intertidal Zostera marina beds in the Salcombe Estuary, Devon, UK. The seagrass bed on the west bank comprised a continuous meadow of ca. 2.3 ha, whilst the bed on the east bank of the estuary was fragmented into patches of 6–9 m2. 2. Three 10 cm diameter core samples for infaunal macroinvertebrates were taken from three stations within each bed. No significant difference was found in univariate community parameters between beds, or in measured seagrass parameters. However, multivariate analysis revealed a significant difference in community composition, due mainly to small changes in species abundance rather than differences in the species present. 3. The species contributing most to the dissimilarity between the two communities were polychaetes generally associated with unvegetated habitats (e.g. Magelona mirabilis) and found to be more common in the fragmented bed. 4. A significant difference in median grain size and sorting coefficient was recorded between the two beds, and median grain size was found to be the variable best explaining multivariate community patterns. 5. The results of the study provide evidence for the effects of habitat fragmentation on the communities associated with seagrass beds, habitats which are of high conservation importance. As the infaunal community is perhaps intuitively the component least likely to be affected by fragmentation at the scale observed, the significant difference in community composition recorded has consequences for more sensitive and high‐profile parts of the biota (e.g. fish), and thus for the conservation of seagrass habitats and their associated communities. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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Spatiotemporal patterns of distribution of sea bass, Dicentrarchus labrax, and sea bream, Sparus aurata, and their influence on artisanal fisheries are explored before and after an escape event that released 1.5 million fish into the wild off La Palma (Canary Islands). Data were collected by in situ visual census and first sale data as a proxy of artisanal fisheries landings. Permutational anova of escapee abundances in shallow coastal habitats revealed consistent spatial patterns that linked densities of these fish to distance from escape point, whereas temporal patterns were related to a higher biomass released during winter. A nearby marine protected area did not show different densities of escaped fish. Local artisanal fleet catches accurately reflected the massive escape event and offer the main contingency force to mitigate the potential negative effects of massive escape events over shallow coastal habitats. 相似文献