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1.
As natural wetlands have disappeared around the world, artificial wetlands have increased. We found interesting differences in waterbird communities of two natural (Bundala Ramsar site) and seven artificial wetlands (irrigation tanks, salt ponds, rice paddies) in south-east Sri Lanka. Eight species exclusively used natural and one species artificial wetlands. Migratory species (shorebirds 64%, terns 47%) dominated species’ richness of natural lagoons, with densities of shorebirds 3-6 times greater than on artificial wetlands. Contrastingly, resident species (dabbling ducks, gallinules) contributed most to the diversity (59%) and density of waterbirds on artificial irrigation tanks. Cattle egrets dominated waterbird density (>70%) of rice paddies. Waterbird communities reflected physical and chemical character of wetlands: natural wetlands were shallow (<2 m) and saline (EC > 1000 msm−1) compared to deep (>2 m) and freshwater (EC < 110 msm−1) artificial wetlands. Artificial inputs of water drained into the natural Embilikala lagoon changing its physico-chemical profile and disrupting the natural seasonal drying. Consequently its waterbird community was similar to artificial irrigation tanks, with shorebird species particularly impacted: densities half that of the other natural lagoon. Artificial salt ponds had similar physico-chemical properties to the natural Bundala lagoon and a similar waterbird community. Even though artificial wetlands supported waterbirds, they were not adequate replacements for loss of natural wetlands, favouring some species. Imposed hydrological stability degraded habitat quality for migratory shorebirds on one of our Ramsar site lagoons. 相似文献
2.
The Guadalquivir Marshes or Doñana wetland complex is the most important wintering site for migratory waterbirds in the Mediterranean region. However, there is a lack of previous information on the status of different species in this area. Using monthly aerial counts conducted from 1978 to 2005, we analysed the size of wintering populations of 21 waterbird species, their distribution within the Guadalquivir Marshes, and their long-term population trends. We used Underhill indices to replace missing values and to correct for flocks of unidentified ducks. Based on long-term means, we identified 16 species whose populations at Doñana exceed 1% of the biogeographical flyway population. For at least 1 month of the year, mean counts were around 10% of the flyway population for six species. The natural, temporary marshes of Doñana National Park were particularly important for Anatidae, ricefields for gulls, white storks and grey herons, fish ponds for flamingos, cormorants and avocets, and salt pans for shelduck. Four Anatidae species have undergone long-term declines and eight non-Anatidae have undergone long-term increases. Population trends were related with trophic guild, migratory status and habitat use. Winter visitors and herbivorous species showed more negative trends than resident, omnivorous-carnivorous species. Those species concentrated in strictly-protected natural marshes have tended to decline. The surface area of ricefields and fish ponds has increased over the study period, and bird species concentrated in these artificial wetlands have tended to increase. This raises questions about the value of waterbirds as flagship or umbrella species for wetland conservation. 相似文献
3.
Those sites designated under the Ramsar Convention on Wetlands of International Importance especially as Waterfowl Habitat constitute the most important wetland conservation network at a global level, with more than 1000 sites of international importance. With only seven designated sites, waterfowl and wetlands in Mexico are evidently under-represented in the list. We identify 34 currently undesignated sites in Mexico that qualify as wetlands of international importance, based on waterfowl count data from 1991-1997, using the Ramsar Convention criteria based on waterfowl. Using a complementarity approach implemented by linear integer programming, the sites were prioritised into two categories on the basis of their importance for designation. Twelve sites were categorised as Priority 1 (higher), and 22 sites as Priority 2 (lower). The Priority 1 set has held a waterfowl count average of 1.2 million individuals, and between 1% (ruddy duck, Oxyura j. jamaicensis) and 51% (black brant, Branta bernicla nigricans) of the populations of 10 species of waterfowl, and includes sites from eight biogeographic regions. 相似文献
4.
Wetland creation aiming at a simultaneous increase in nutrient retention and species diversity in agricultural landscapes has recently become applied as a catchment-scale compensation measure for past wetland losses. Here, we evaluate if, and to what extend, dual-purpose wetlands benefit local and regional diversity of agricultural landscapes. We analysed composition and α, β, and γ diversity of aquatic macroinvertebrate assemblages among dual-purpose wetlands in an agricultural region in southwest Sweden in relation to local (water quality, wetland morphology, succession stage, proximity to other aquatic habitats) and landscape parameters (regional connectivity, wetland density). Diversity of mature agricultural ponds was used as a standard to evaluate the value of dual-purpose wetlands. Dual-purpose wetlands sustained α, β, and γ diversity similar to that of natural lentic water bodies in agricultural landscapes in the region and elsewhere. Over 80% of the overall species richness was attributed to β diversity, and each created wetland contributed to overall species accumulation. Ecosystem parameters explained 19% of the compositional variation among assemblages, but were only marginally related to diversity. Wetland density promoted α and γ diversity, while spatial heterogeneity (β) remained equally high, independent of wetland density. Our results indicate that catchment-scale wetland creation for simultaneous retention and diversity purposes benefits the biodiversity of agricultural landscapes, particularly if the density of aquatic habitats is increased by at least 30%. 相似文献
5.
While the importance of nearby terrestrial habitats is gaining recognition in contemporary wetland management strategies, it is rarely recognized that different wetlands are often diverse in their functions of meeting the annual or life-cycle requirements of many species, and that migration between these wetlands is also critical. Using radio-telemetry, we examined terrestrial habitat use and movements of 53 eastern long-necked turtles (Chelodina longicollis) in an area of southeast Australia characterized by spatially diverse and temporally variable wetlands. Male and female C. longicollis exhibited a high degree of dependence on terrestrial habitat, the majority (95%) of individuals using sites within 375 m of the wetland. Turtles also associated with more than one wetland, using permanent lakes during droughts and moving en masse to nearby temporary wetlands after flooding. Turtles used 2.4 ± 0.1 (range = 1-5) wetlands separated by 427 ± 62 (range = 40-1470) m and moved between these wetlands 2.6 ± 0.3 (range = 0-12) times over the course of a year. A literature review revealed that several species of reptiles from diverse taxonomic groups move between wetlands separated by a mean minimum and maximum distance of 499-1518 m. A high proportion of studies attributed movements to seasonal migrations (55%) and periodic drought (37%). In such cases we argue that the different wetlands offer complimentary resources and that managing wetlands as isolated units, even with generous terrestrial buffer zones, would not likely conserve core habitats needed to maintain local abundance or persistence of populations over the long term. Core management units should instead reflect heterogeneous groups of wetlands together with terrestrial buffer zones and travel corridors between wetlands. 相似文献
6.
Ecologists increasingly recognise the importance of spatial scale for conservation. This study focuses on threatened temporary wetland crustaceans, the fairy shrimp Branchinecta orientalis Sars (Anostraca) and the tadpole shrimp Triops cancriformis Bosc (Notostraca). Using redundancy analyses with a canonical variance partitioning approach, we studied how local habitat conditions and landscape features influence their densities at 4 spatial scales (100 m buffer strip around ponds, 1 km, 5 km and 10 km catchment scales). Branchinecta densities were negatively related with local conditions (trophic status) at all scales. Landscape effects (catchment:wetland size ratio) were only significant at the 10 km scale. However, trophic state conditions were influenced by local contamination rather than landscape conditions. Local degradation tended to be more pronounced in wetlands situated in catchments with a higher cover of natural vegetation compared to those in agricultural catchments. Triops was less influenced by local effects at all scales. The importance of landscape effects increased with landscape scale but effects were only significant at the 10 km scale, and were negatively explained by irrigated croplands. The importance of broad landscape scales and the difficulty to restore locally degraded sites challenges management. Because rationalisation of large-scale agricultural practises can conflict with socioeconomic demands, a first step to the conservation of actual Branchiopoda populations in this remnant wetland complex could benefit from the creation of vegetated buffer strips around the wetlands and/or hedgerows around agricultural fields to counteract atmosphere-mediated flux of particles and solutes from croplands to wetlands at broad landscape scales. 相似文献
7.
Estimates of the number of waterbirds (principally wildfowl) wintering in Great Britain are presented, based on data from the period 1994/1995-1998/1999. These update the previous estimates for 1987/1988-1991/1992. National estimates are used to derive 1% thresholds for waterbird species which in turn form the basis for the identification of nationally important wetland sites for subsequent conservation and protection. Estimates are also used to assess changes in numbers of those species for which monitoring data are insufficient to calculate annual indices of population change. Data for calculating the estimates come from a variety of sources including the Wetland Bird Survey (WeBS, a long-term scheme which counts waterbirds by day at wetlands), goose roost censuses, site-based surveys and published reviews. Generation of the estimates is made difficult by a number of methodological and data quality issues. To account for some of the methodological problems affecting WeBS data, new methods for generating estimates have been used which account for birds missed during the counts in a more comprehensive manner. These result in large increases in the estimated numbers for many of the relevant species, although most are still considered to be underestimates. To assess the biological change in numbers since the last assessment, estimates generated from the same methods used previously are also presented. These indicate that while the majority of species have experienced increases in numbers since the late 1980s there have been some notable declines. There is however scope for improving the accuracy of estimates derived from extensive, volunteer-based monitoring schemes such as WeBS. 相似文献
8.
John Thorbjarnarson Xiaoming WangShao Ming Lijun HeYouzhong Ding Yuelong WuScott T McMurry 《Biological conservation》2002,103(1):93-102
The Chinese alligator, Alligator sinensis, is on the verge of becoming extinct in the wild as a result of loss of natural wetlands in the lower Changjiang valley. Chinese alligators are only known from a small region in southeastern Anhui province, a fraction of its former distribution. Within this area, a 433 km2 reserve has been declared that contains 13 designated habitat sites totaling 41 ha. The sites consist of small ponds located within or adjacent to villages, are completely surrounded by rice fields, or are biologically marginal oligotrophic ponds set in low hills. Alligators are only present at 10 of the 13 designated sites, with the largest groups containing a maximum of 10-11 animals and one adult female. In recent years nesting is known from only four areas, but the eggs are routinely collected and hatchlings retained in the Anhui alligator breeding center. The total population of wild Chinese alligators is probably <130 and is declining at an annual rate of 4-6%. If present trends continue, the Chinese alligator will be the first species of crocodilian to become extinct in the wild in historical times. Conservation efforts need to focus on protection of remaining wetlands and wetland restoration, and the inclusion of Chinese alligators in the active management of protected wetlands sites throughout the species' historic distribution. 相似文献
9.
Multistate assessment of wetland restoration on CO2 and N2O emissions and soil bacterial communities
Over the last 200 years, wetlands have been converted to other land uses leading to the loss of approximately 53% of wetlands in the continental United States. In the late 1980's, policies were instated to mitigate further wetland loss through wetland creation and restoration. Restored wetlands provide important ecosystem services, such as filtration of nutrients and wildlife habitat. However, these benefits could be offset by increased greenhouse gas production. We assessed the impact of wetland conversion to agriculture and restoration on CO2 and N2O emissions and microbial communities in three land use types: wetlands with native vegetation (natural); wetlands converted to agricultural management (converted); and restored wetlands (restored). Soil properties varied among land use types. Most notably, soils from restored and converted sites had the lowest C and N, and higher pH. Multivariate analysis of soil properties showed the pocosin wetlands in North Carolina separating from all other locations, regardless of land use. Soil bacterial communities showed a similar trend with communities from North Carolina soils separating from the others with no significant effect of land use or season. Furthermore, land use did not have a significant effect on CO2 or N2O emissions, although there was significant temporal variation in CO2 emissions. These findings indicate that while wetland conversion and restoration may alter some soil properties, these alterations do not appear to be great enough to override the underlying geographic and edaphic influences on soil bacterial communities. Furthermore, wetland restoration did not lead to increased N2O emission at the dates sampled. 相似文献
10.
Shallow open water wetlands provide critical habitat for numerous species, yet they have become increasingly vulnerable to drought and warming temperatures and are often reduced in size and depth or disappear during drought. We examined how temperature, precipitation and beaver (Castor canadensis) activity influenced the area of open water in wetlands over a 54-year period in the mixed-wood boreal region of east-central Alberta, Canada. This entire glacial landscape with intermittently connected drainage patterns and shallow wetland lakes with few streams lost all beaver in the 19th century, with beaver returning to the study area in 1954. We assessed the area of open water in wetlands using 12 aerial photo mosaics from 1948 to 2002, which covered wet and dry periods, when beaver were absent on the landscape to a time when they had become well established. The number of active beaver lodges explained over 80% of the variability in the area of open water during that period. Temperature, precipitation and climatic variables were much less important than beaver in maintaining open water areas. In addition, during wet and dry years, the presence of beaver was associated with a 9-fold increase in open water area when compared to a period when beaver were absent from those same sites. Thus, beaver have a dramatic influence on the creation and maintenance of wetlands even during extreme drought. Given the important role of beaver in wetland preservation and in light of a drying climate in this region, their removal should be considered a wetland disturbance that should be avoided. 相似文献
11.
In the environs of the town of El Kala in northeast Algeria there are some extensive wetlands of great ornithological, and probably also other biological, importance. The most important are ‘Lake’ Tonga, a marsh of about 2700 ha with much Scirpus lacustris; Lake Oubeïra, a freshwater lake of about 2200 ha; Lake Mellah, where fresh water from brooks and sea water meet, of about 800 ha; Garaet el Mekhada, a Scirpus maritimus marsh of about 5600 ha and swamp forests, which could not be investigated.Many species of waterfowl were seen in the second half of May, 1976. From these and some other observations probable breeding may be derived in many cases. Important species in the region are: squacco heron Ardeola ralloides (about 100 seen), cattle egret Bubulcus ibis (about 2000 seen), little egret Egretta garzetta (about 65 seen), grey heron Ardea cinerea (rare), purple heron Ardea purpurea (about 60 seen, possibly far more present), little bittern Ixobrychus minutus, bittern Butaurus stellaris and night heron Nycticorax nycticorax.Beside herons, the following species were seen: ferruginous duck Aythya nyroca (about 100 seen, probably far more numerous and hidden by the vegetation), white-headed duck Oxyura leucocephala (some 50 seen, probably present in greater numbers), marbled teal Anas angustirostris, purple gallinule Porphyrio porphyrio (common in Tonga). Interesting birds of prey in the region were griffon vulture Gyps fulvus (up to 30), marsh harrier Circus aeruginosus (rather numerous in Tonga), tawny eagle Aquila rapax (probably breeding on one place) and Eleonora's falcon Falco eleonorae (up to 5).As to probable breeding birds, Tonga has the greatest density of species and individuals, but other wetlands also have important aspects.Probably the most important lake for breeding birds, Fetzara (near Annaba), was drained in 1937. Marbled teal, ferruginous duck and purple gallinule were very common there, and white-headed duck, purple heron, squacco heron, night heron, little egret, spoonbill Platalea leucorodia, glossy ibis Plegadis falcinellus, grey-lag goose Anser anser, red-crested pochard Netta rufina and gadwall Anas strepera used to breed.A brief review is given of wintering waterfowl, mainly based on counts by different observers in the period 1971–1979. Large numbers of waterfowl have been seen in Lake Oubeïra; up to 5000 pintail Anas acuta, up to 14000 wigeon Anas penelope, up to 27000 pochard Aythya ferina, up to 9000 tufted duck Aythya fuligula and up to 32000 coot Fulica atra, up to 850 black-necked grebe Podiceps nigricollis and up to 2300 little grebe Tachybaptus ruficollis.In Lake Mellah up to 9000 pochard have been seen, up to 12000 tufted duck, and up to 35000 coot.In Garaet al Mekhada up to 25000 wigeon, up to 5000 coot and up to 8000 grey-lag geese have been seen. It seems quite possible that the 95000 wigeon seen by Smart in the artificial lake of the Barrage de la Cheffia in 1974 fed in Mekhada. An insight of waterfowl averages during the different counts can be obtained from the reports, mentioned in the references.All large wetlands mentioned have a high, actual or potential, ecological value. Each of them deserves protection and, from the ecological viewpoint, Fetzara merits inundation. Protection should be aimed at the preservation of the special character of each of the wetlands and of their mutual relationship for birds.The region is the most important in Algeria for wintering duck and coot (an average of 93000 from 1974–1978) and probably also for breeding waterfowl (especially Tonga) in spite of the high quality of La Macta in West Algeria.For the preservation of this diversity, several factors are essential, e.g., water level, water quality, absence of exotic elements in the water fauna and a relatively low shooting pressure (with little disturbance). It is important to prevent drainage of the lakes and of their surroundings, afforestation of the adjacent land, deforestration and erosion in the catchment areas, introduction of exotic fish species—and it is important to introduce good rules concerning shooting.This complex of wetlands is part and parcel of an extensive area of high biological interest, of which the marine habitats and large semi-natural forests are also remarkable.It is to be hoped that this entity will be efficiently protected in the framework of the National Park of El Kala Project. 相似文献
12.
A. Guillet 《Biological conservation》1978,13(1):39-49
The report deals with the distribution of the shoebill stork (Balaeniceps rex) in wetlands in the southern Sudan. The shoebill is a highly specialised bird requiring resources which are limited and which are discontinuously distributed in time and space. The bird's habitat is affected by a variety of artificial factors which are contributing to increasingly widespread ecological degradation of the natural wetlands. The survival of the shoebill is threatened, and the declining status of the species merits international recognition and conservation attention. 相似文献
13.
We used models integrating road maps, traffic volume, and snake movements to examine the potential for roads to contribute to mortality in two species of water snakes that differ in their vagility, use of terrestrial habitats, and conservation status. Road networks and traffic volumes typical of three regions in Indiana, USA, may account for mortality of 14-21% of the population per year in the more vagile, terrestrial, and imperiled copperbelly water snake (Nerodia erythrogaster neglecta) but only 3-5% mortality in the more sedentary, aquatic, and common northern water snake (Nerodia sipedon). The majority (>91%) of road crossings and associated mortality are predicted to occur during overland migrations to other wetlands, suggesting roads bisecting travel routes between wetlands may function as mortality sinks. Our models highlight the proportionately greater risk of mortality for the more vagile and imperiled species, N. e. neglecta, and suggest current wetland conservation strategies that focus on the wetland alone are unlikely to adequately protect wetland biodiversity from certain types of anthropogenic habitat modification. What is needed is a landscape approach to wetland conservation that considers not only the quality of wetlands and nearby terrestrial habitats, but also ensures that terrestrial corridors between wetlands remain permeable and offer safe passage for wildlife. 相似文献
14.
Walter H PiperMargaret Klich Keren B TischlerAmy Dolsen 《Biological conservation》2002,104(2):199-203
Many southern populations of the common loon (Gavia immer) face threats from lead and methylmercury contamination, lake acidification, shoreline development and human recreation. It is now clear that the task of conserving loon populations will depend upon mitigating these varied threats. In a controlled experiment, we examined the efficacy of using floating nest platforms to increase reproductive success of loons and thus help sustain local populations. Platforms were attractive nesting sites both on lakes that had consistently hatched chicks from natural sites and on lakes where chick production had been sporadic. When compared to natural nest sites, platforms increased hatching success by 69% and fledging success by 32%, apparently through reduction in mammalian egg predation. A well-managed effort to introduce nesting platforms might be a viable strategy to help sustain threatened populations. 相似文献
15.
Luba V BalianMamikon G Ghasabian Martin S Adamian Daniel Klem Jr 《Biological conservation》2002,106(2):157-163
Waterbird species richness (Gaviiformes, Podicipediformes, Pelecaniformes, Ciconiiformes, Phoenicopteriformes, Falconiformes, Anseriformes, Gruiformes, Charadriiformes, Passeriformes) has been significantly affected by a 19.5 m lowering of the water level in Lake Sevan (1933-2000), and the complete draining of nearby Lake Gilli (1960-2000) in the Republic of Armenia. Twenty-three former breeders are currently nonbreeders in the area. Four former breeders (black stork Ciconia nigra, glossy ibis Plegadis falcinellus, white-winged scoter Melanitta fusca, little crake Porzana parva) have been extirpated from the area. Four former nonbreeders (cattle egret Bubulcus ibis, red-breasted goose Branta ruficollis, sociable lapwing Chettusia gregaria, lesser black-backed gull Larus fuscus) have been absent from the area for at least 20 years. The red-breasted merganser Mergus serrator is the only former nonbreeder discovered breeding in the Lake Sevan basin. We recommend that management plans of the 1960s and 1970s be used to further develop and enact new efforts to increase the water level of Lake Sevan by at least 6 m, and that Lake Gilli and its surrounding wetlands be restored as a means of increasing waterbird species richness overall, and protecting regional populations of globally threatened or near-threatened species (Dalmatian pelican Pelecanus crispus, red-breasted goose Branta ruficollis, ferruginous pochard Aythya nyroca, white-headed duck Oxyura leucocephala, corn crake Crex crex, great snipe Gallinago media, black-winged pratincole Glareola nordmanni, white-tailed eagle Haliaeetus albicilla). 相似文献
16.
霍林河流域湿地土地利用/土地覆被类型的渐变过程 总被引：6，自引：5，他引：6
研究了霍林河流域自然湿地和人工湿地的面积动态变化以及土地利用/覆被变化过程——渐变过程,结果表明1986～2000年期间自然湿地的面积呈缩减变化,而人工湿地面积则呈增长变化;1986～1996年期间除河流湿地没有发生渐变过程外,其它类型湿地之间普遍存在着渐变过程,其中沼泽的渐变过程最为显著,表现为大幅度缩减,而滩地、湖泊、水库坑塘和水田在渐变过程中则表现为增加变化。1996～2000年期间各类型湿地之间普遍存在着渐变过程,但不同的是,沼泽湿地面积在渐变过程中表现为大幅度增加,而河流、滩地、湖泊和水库坑塘却表现为大幅度缩减;同时沼泽、滩地、湖泊以及水库坑塘在此期间都有向水田发生转变,表明人类的活动范围在不断的扩展,对湿地的开垦力度也在不断加强。 相似文献
17.
Christophe Tourenq Robert E. Bennetts Hubert Kowalski Emmanuel Vialet Jean-Laurent Lucchesi Yves Kayser Paul Isenmann 《Biological conservation》2001,100(3):335-343
Rice cultivation has frequently been suggested to provide an important wetland habitat for waterbirds. However, in contrast to most other regions of the Mediterranean, the Camargue still has a substantial amount of surface area of natural marshes. Thus, we compared the abundance, species richness, and community composition of waterbirds in ricefields and natural marshes of the Camargue, during a one-year study. Based on surveys conducted at 4–7 day intervals in 1997–1998, our results suggest that natural marshes had substantially greater abundance of waterbirds, with ca. 99% of the individuals having been observed in natural marshes. Estimates of species richness and associated parameters further indicated that ricefields were clearly less rich than natural marshes. Although our results were rather striking for the Camargue, they may not be applicable to other regions because of the relatively high availability of natural marshes and differences in management of ricefields. 相似文献
18.
Invasive plants can threaten diversity and ecosystem function. We examined the relationship between the invasive Phalaris arundinacea (reed canarygrass) and species richness in beaver wetlands in Oregon, USA. Four basins (drainages) were chosen and three sites each of beaver impoundments, unimpounded areas and areas upstream of debris jams were randomly chosen in each basin for further study (n = 36). Analysis of covariance (ANCOVA) showed that the relationship between Phalaris and species richness differed significantly (p = 0.01) by site type. Dam sites (beaver impoundments) exhibited a strong inverse relationship between Phalaris and species richness (bD = −0.15), with one species lost for each 7% increase in Phalaris cover. In contrast, there was essentially no relationship between Phalaris cover and species richness in jam sites (debris jam impoundments formed by flooding; bJ = +0.01) and unimpounded sites (bU = −0.03). The cycle of beaver impoundment and abandonment both disrupts the native community and provides an ideal environment for Phalaris, which once established tends to exclude development of herbaceous communities and limits species richness. Because beaver wetlands are a dominant wetland type in the Coast Range, Phalaris invasion presents a real threat to landscape heterogeneity and ecosystem function in the region. 相似文献
19.
洞庭湖区湿地景观变化分析 总被引：3，自引：0，他引：3
洞庭湖湿地是我国最重要湿地系统之一,具有多方面功能和价值,主要由河流、湖泊、水田、沼泽、滩地、库塘等几种类型组成。本文利用1980年、1990年、2000年3个时段的Landsat MSS和TM影像及GIS技术对洞庭湖区湿地景观变化进行研究。结果表明,洞庭湖区湿地总面积呈减少趋势,人工湿地面积有所增加,自然湿地面积减少,其中湖泊面积减少最多。这是人类和自然共同作用的结果,其中人类对湿地的改造是导致变化的主要原因,但洞庭湖的泥沙淤积是湖泊面积减少的根本原因。湿地景观的改变导致该区生态环境质量下降,生态功能退化。 相似文献
20.
Experiments were conducted in two Danish coastal wetland areas to assess the applicability of regulating wildfowling in marsh areas by restricting shooting to a period of the day as an alternative to apply spatial regulation. Teal (Anas crecca) showed a 2-97-fold increase when shore-based shooting was totally banned, compared with years when shore-based shooting was unregulated or diurnally regulated. The same result was found for common snipe (Gallinago gallinago) at its one studied area (15-39-fold increase). Shelduck (Tadorna tadorna), teal and mallard (A. platyrhynchos) spent more time in the zones nearest to the shoreline when shore-based shooting was totally banned than when evening shooting was permitted. It is concluded (1) that disturbance levels were not sufficiently reduced by temporal regulation to prevent teal and snipe from abandoning otherwise attractive staging areas, and (2) that reserves should incorporate adjacent marshes in the non-shooting refuge to ensure high species diversity. 相似文献