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Robert Nikolaus Malwina Schafft Andreas Maday Thomas Klefoth Christian Wolter Robert Arlinghaus 《水产资源保护:海洋与淡水生态系统》2021,31(1):153-172
- Humanity is facing a biodiversity crisis, with freshwater-associated biodiversity in a particularly dire state. Novel ecosystems created through human use of mineral resources, such as gravel pit lakes, can provide substitute habitats for the conservation of freshwater and riparian biodiversity. Many of these artificial ecosystems are subject to a high intensity of recreational use, however, which may limit their biodiversity potential.
- The species richness of several taxa (plants, amphibians, dragonflies, damselflies, waterfowl, and songbirds) was assessed and a range of taxonomic biodiversity metrics were compared between gravel pit lakes managed for recreational fisheries (n = 16) and unmanaged reference lakes (n = 10), controlling for non-fishing-related environmental variation.
- The average species richness of all the taxa examined was similar among lakes in both lake types and no substantial differences in species composition were found when examining the pooled species inventory. Similarly, there were no differences between lake types in the presence of rare species and in the Simpson diversity index across all of the taxa assessed.
- Variation in species richness among lakes was correlated with woody habitat, lake morphology (surface area and steepness), and land use, but was not correlated with the presence of recreational fisheries. Thus, non-fishing-related environmental variables had stronger effects on local species presence than recreational fisheries management or the presence of recreational anglers.
- Collectively, no evidence was found that anglers and recreational fisheries management constrain the development of aquatic and riparian biodiversity in gravel pit lakes in the study region; however, the conservation of species diversity in gravel pit lakes could benefit from an increasing reliance on habitat enhancement activities.
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Norman Mercado‐Silva John Lyons Edmundo Díaz‐Pardo Altagracia Gutirrez‐Hernndez Claudia Patricia Ornelas‐García Carlos Pedraza‐Lara M. Jake Vander Zanden 《水产资源保护:海洋与淡水生态系统》2006,16(5):533-546
- 1. The structure and composition of fish communities in rivers of central Mexico have been altered as a result of water over‐exploitation, habitat fragmentation, introduction of exotic species, and pollution. However, the specific pattern and degree of change are poorly documented.
- 2. Long‐term information from the Laja River (Guanajuato, Mexico) in the Lerma River basin was used to explore trends in fish species richness and community composition (species origin, trophic niche, tolerance, and preferred habitat) from the 1960s to the present in both river and reservoir sites.
- 3. Declines in native, sensitive, benthic native and carnivore species ranging from 11% to 30% per decade, and increases in the number of tolerant and exotic species by 9–20% per decade, are documented. Repeated measures ANOVA and sign tests revealed significant declines in the number of benthic, native, carnivore and sensitive species. Species richness, number of exotics, tolerant species and omnivore species did not change statistically, though statistical power was low. Some important changes occurred in these variables, such as the expansion and establishment of exotics such as Xiphophorus variatus and Micropterus salmoides, which pose a serious potential threat to native species.
- 4. The changes in fish community composition for the Laja portray how the fish communities in other rivers in central Mexico, for which long‐term data do not exist, have changed or could change if environmental deterioration continues.
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Arely Ramírez-García Omar Domínguez-Domínguez Eugenia López-López Rodrigo Moncayo-Estrada José De La Cruz-Agüero 《Ecology of Freshwater Fish》2023,32(1):53-63
In spring lakes, which have homogeneous environmental characteristics, it is expected that there will be no significant changes in the composition and structure of communities over time, and fluctuations will generally be related to the ecological attributes of the species. We studied the fish community in a small subtropical spring lake, Lake Zacapu, for two different decades to analyse its structural characteristics. Sampling was performed every 3 months at four sites from January to October 1995 and from May 2019 to May 2020. We determined the temporal variation (seasonal and decadal) in the fish community structure with respect to composition, abundance, diversity and dominance. We evaluated the association between species and water quality. Our results showed spatial homogeneity in most physicochemical variables that remained in the same range across decades, although some nutrients (NO3) recently increased. All species identified in the early samples were present in the recent surveys (eleven native and two nonnative species), indicating that the fish community composition had significant qualitative stability. However, the dominant littoral cyprinid in 1995 was replaced by the more limnetic atherinopsid in 2019–2020, and the diversity and abundance of sensitive fish decreased in recent samplings. Consequently, the current status of critically endangered species is supported for some restricted and microendemic fish. The changes in the community structure attributes, which show a tendency for reduction in native species, emphasise the need to implement efforts to conserve freshwater fish diversity in small spring lakes. 相似文献
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Antonella Carosi Lucia Ghetti Rosalba Padula Massimo Lorenzoni 《Fisheries Management and Ecology》2019,26(6):500-511
Global climate changes have led to a gradual warming of the planet, resulting in decreased precipitation and rising temperatures in Mediterranean inland waters. In Trasimeno Lake, the largest shallow lake in Italy, some non‐native fish species have probably benefited from these changes as they are thermophilic and characterised by wider habitat preferences. Fish data collected by gillnets and fyke nets between 1956 and 2016, and by electrofishing in 1993 and 2014, were used to analyse changes over time in the fish community in relation to environmental conditions. An explosion in goldfish Carassius auratus (L.), following its introduction in 1988, coupled with water level fluctuations and reduced transparency, contributed to the reduction in commercial fish catch in the lake, and to the decline of the endemic southern pike Esox cisalpinus Bianco & Delmastro, already threatened by reduced spawning habitat and interspecific competition with other non‐native predatory fishes. 相似文献
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- 1. Chilean rivers have a large potential for hydropower development, and they also contain a unique native fish fauna with a high level of endemism. Several diversion hydropower plants have recently been constructed in Chile; however, the response of fish communities to these new hydropower plant designs is not well known.
- 2. Responses of native and non‐native fish to the construction and operation of a new hydropower plant that diverts water from two rivers were quantified. The Laja River is highly regulated and manipulated with three older (40 yr) dam‐based hydropower plants and irrigation diversions located upstream from the new facility. In contrast, the Rucúe River has no other hydropower facilities and is comparatively undisturbed.
- 3. Prior to construction, the Laja River had a fish community with lower species richness compared with the Rucúe River. The fish community structure in the Laja River was dramatically altered after the new hydropower facility began operation. On the other hand, in the Rucúe River, even though abundance of fish declined, there was less of a change in the total fish community structure. The fish community in the Rucúe River exhibited greater resistance to change compared with the Laja River.
- 4. The species most affected were the introduced salmonids and an endangered native species Percilia irwini.
- 5. Although diversion hydropower designs may have less impact than traditional dam‐based hydropower facilities, results of this study indicate that diversion hydropower structures can cause large changes in the fish community.
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Tributaries of the Colorado River Basin, historically home to a complex of endemic omnivores collectively referred to as the ‘three species’; flannelmouth sucker (Catostomus latipinnis), bluehead sucker (C. discobolus) and roundtail chub (Gila robusta), have experienced the establishment of numerous non‐native fish species. In this study, we examine the impacts of the trophic ecology of non‐native fishes on the ‘three species’ in the San Rafael River, Utah, USA. We employ a suite of abundance comparisons, stable isotope techniques and size‐at‐age back‐calculation analyses to compare food web structure and growth rates of the ‘three species’ in study areas with and without established populations of non‐native species. We found that the ‘three species’ are more abundant in areas with few non‐native fishes present, regardless of habitat complexity. Stable isotope analyses indicate non‐native fishes lengthen the food chain by 0.5 trophic positions. Further, the trophic niche spaces of the native fishes shift and are narrower in the presence of non‐native fishes, as several non‐native species’ trophic niche spaces overlap almost entirely with each of the ‘three species’ (bluehead sucker and flannelmouth sucker 100%, roundtail chub 98.5%) indicating strong potential for competition. However, the ‘three species’ demonstrated no evidence of reduced growth in the presence of these non‐native fishes. Collectively, these results suggest that while non‐native fishes alter the food web structure presenting novel sources of predation and competition, mechanisms other than competition are controlling the size‐structure of ‘three species’ populations in the San Rafael River. 相似文献
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Assessing long‐term fish responses and short‐term solutions to flow regulation in a dryland river basin 
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下载免费PDF全文 Water resource development and non‐native species have been cited as primary drivers associated with the decline of native fishes in dryland rivers. To explore this topic, long‐term trends in the fish community composition of the Bill Williams River basin were studied over a 30‐year period (Arizona, USA). We sampled 31 sites throughout the basin that were included in fish surveys by Arizona Game and Fish in 1994–97 and the Bureau of Land Management in 1979–80. We found that non‐native species have proliferated throughout the entire basin, with greater densities in the lower elevations. Native species have persisted throughout most of the major river segments, but have experienced significant declines in frequency of occurrence and abundance in areas also containing high abundances of non‐native species. Next, we assessed the short‐term response of the fish assemblage to an experimental flood event from the system's only dam (i.e. Alamo Dam). In response to the flood, we observed a short‐term reduction in the abundance of non‐native species in sites close to the dam, but the fish assemblage returned to its preflood composition within 8 days of the event, with the exception of small‐bodied fish, which sustained lower postflood densities. Our findings demonstrate the importance of natural flow regime on the balance of native and non‐native species at the basin scale within dryland rivers and highlight minimal effects on non‐native fishes in response to short duration flood releases below dams. 相似文献
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A simple approach for assigning the conservation status of freshwater fish based on their natural variability – a case study from the Iberian Ecoregion 下载免费PDF全文
下载免费PDF全文 A simple, non‐lethal method for assigning conservation status is proposed based on three conservation classes (favourable, unfavourable/inadequate and unfavourable/bad) to fish species based on their natural population variability. To demonstrate this approach, conservation classes were allocated to three native fish species (brown trout Salmo trutta L., northern Iberian chub Squalius carolitertii (Doadrio), and northern straight‐mouth nase, Pseudochondrostoma duriense (Coelho) based on basic population variables (density and biomass) using a 9‐year dataset (2004–2012) from 15 different sampling sites in Spain. The classification of the population variables into conservation classes was made using previously described nonparametric methods and percentiles categorisation, and the current conservation status of the studied species was established. Temporal trend analyses showed that S. carolitertii experienced a progressive significant decrease during the study period, whereas both S. trutta and P. duriense exhibited weak increases in density. The study exemplifies the need to quantify the natural variability of fish resources to reveal their current conservation status and to determine whether short‐term and long‐term management actions are needed to rehabilitate native fish assemblages. The proposed approach could easily be employed by fisheries managers to monitor the conservational status of other native species. 相似文献
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Larissa Faria Mhairi E. Alexander Jean R. S. Vitule 《Fisheries Management and Ecology》2019,26(6):570-577
In the metric “Relative Impact Potential” (RIP), the functional response (FR) of a non‐native species can be compared with that of a native analogue and combined with the species abundance to predict its environmental impact. Here, using the River Guaraguaçu (Brazil) as a case study, this methodology was implemented to identify the impacts of the non‐native channel catfish Ictalurus punctatus (Rafinesque) compared with a native species Rhamdia quelen (Quoy & Gaimard) towards small prey fish. Both species exhibited Type II FRs, but handling times were lower for I. punctatus, resulting in a greater maximum feeding rate in this species. Consequently, an RIP > 1 was found, indicating that I. punctatus represents a superior impact to prey compared with its native analogue. These results demonstrate that I. punctatus is a potential threat to small endangered fish species; therefore, policies to avoid escapes from aquaculture should be created and the abundance of I. punctatus controlled. 相似文献
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Can underwater refuges protect fish populations against cormorant predation? Evidence from a large‐scale multiple pond experiment 下载免费PDF全文
下载免费PDF全文 Artificial structures can protect fish against predation by cormorants (Phalacocorax spp.). However, their effectiveness in larger water bodies with different fish communities in the presence of natural vegetation still needs to be explored. Using a large‐scale field experiment with 24 ponds stocked with differently composed fish communities, the present study investigates the extent to which the effect of artificial refuges on fish is species‐specific and determined by the characteristics of the fish community. This study provides strong experimental evidence for artificial refuges protecting fish against predation from cormorants, even in the presence of submerged vegetation. The effect of refuges was, however, highly species‐specific and depended on the composition of the fish community. Strong positive effects of refuges on rudd, Scardinius erythrophthalmus (L.), and roach, Rutilus rutilus (L.), populations were observed, especially in ponds where these species dominated. Overall, the total biomass of young‐of‐the‐year, 1‐year‐old and adult rudd and roach was on average 500, 7 and 15 times lower in ponds without than in ponds with refuges, respectively. No effect of artificial refuges on other fish species was found. This study indicates that artificial refuges can facilitate the coexistence of predation vulnerable fish populations with cormorants in lakes and ponds. 相似文献
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Nixie C. Boddy Kevin M. Fraley Helen J. Warburton Phillip G. Jellyman Doug J. Booker Dave Kelly Angus R. McIntosh 《水产资源保护:海洋与淡水生态系统》2020,30(1):159-172
- Abstractions and diversions are prevalent in river networks worldwide; however, specific mechanisms and measures reflecting changes in functional characteristics of aquatic assemblages in response to flow abstraction have not been well established. In particular, the influence of small takes on fish assemblages is poorly understood.
- Field surveys and stable‐isotope analyses were used to evaluate the impact of differing levels of flow abstraction on fish assemblage structure, and native–non‐native patterns of coexistence, associated with small surface water abstractions in four streams in New Zealand. Study design accounted for longitudinal processes (spatial autocorrelation) to isolate the effects of abstractions on fish assemblages.
- Reaches with reduced flows downstream of abstraction points had significantly lower fish abundances per metre of stream length, probably because of decreased habitat size, altered interspecific interactions and barriers to movement. The loss of larger fish in reaches with high abstraction resulted in shallower mass–abundance slopes and shorter stable isotope‐derived food‐chain lengths, likely to have been caused by fewer trophic links in the food web. The large fish absent from these reaches were flow‐sensitive introduced salmonids, resulting in higher relative abundances of small‐bodied native fish, probably as a result of predatory and competitive release.
- Quantification of metrics designed to characterize ecosystem functioning as well as abundance and species composition indicated that small water abstractions can alter both the structure and composition of stream fish assemblages and modify the outcomes of native–non‐native species interactions. Thus, a better understanding of the effects of small abstractions could be used to improve the strategic management of fish in invaded riverscapes.
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Trophic overlap between non‐native brown bullhead (Ameiurus nebulosus) and native shortfin eel (Anguilla australis) in shallow lakes 下载免费PDF全文
下载免费PDF全文 Kevin J. Collier Michael A. Pingram Laura Francis Jeremy Garrett‐Walker Michele Melchior 《Ecology of Freshwater Fish》2018,27(4):888-897
We quantified trophic overlap between the invasive, non‐native catfish brown bullhead (Ameiurus nebulosus) and the New Zealand native shortfin eel (Anguilla australis) in four peat and riverine lakes using stable isotope (δ13C and δ15N) and gut content analyses. Across all lakes and fish sizes over the austral spring–summer period, shortfin eel guts were dominated numerically by fish prey (57% occurrence cf 42% in brown bullhead), while Diptera larvae were most commonly encountered in guts of brown bullhead (45% cf 14% in eels). Significant differences in % composition of animal contents in guts were detected between fish species and sampling occasions (n = 4) but not between lakes. In contrast, stable isotope signatures of brown bullhead and shortfin eel did differ significantly between lakes but not between sampling occasions, indicating enduring sources of nutrition despite apparently differing ingestion patterns over time. The R mixing model MixSIAR indicated that shortfins likely assimilated higher proportions of fish prey carbon compared to brown bullheads, which appeared to show greater assimilation of invertebrates, consistent with the results of gut content analyses. Isotopic niche regions, calculated in nicheROVER using probabilistic ellipses, indicated that shortfin eels occupied at least c.60% of brown bullhead trophic niche, which occupied less than 30% of eel trophic niche in all but one lake. These estimates suggest that brown bullhead has higher potential to influence shortfin eel nutrition than vice versa, or that a broad trophic niche occupied by eels provides resilience to the effects of overlapping consumption patterns with invasive omnivores. 相似文献
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Biodiversity values of remnant freshwater floodplain lagoons in agricultural catchments: evidence for fish of the Wet Tropics bioregion,northern Australia 总被引：1，自引：0，他引：1 下载免费PDF全文
下载免费PDF全文 Angela H. Arthington Paul C. Godfrey Richard G. Pearson Fazlul Karim Jim Wallace 《水产资源保护:海洋与淡水生态系统》2015,25(3):336-352
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Nishikant Gupta Mark Everard Prakash Nautiyal Ishaan Kochhar Kuppusamy Sivakumar Jeyaraj Antony Johnson Atul Borgohain 《水产资源保护:海洋与淡水生态系统》2020,30(2):394-401
- Mahseer (Tor) fish species are critical components of locally adapted freshwater food webs across the Indian Himalayan biodiversity hotspot; however, multiple human stressors compounded by climate change have significantly depleted their populations over recent decades.
- Mahseer species are now considered locally vulnerable or endangered in many regions. Hydropower projects in particular have fragmented populations, impairing genetic exchange, obstructing migratory paths, and changing the structure and functioning of riverine habitats, especially of formerly fast‐flowing rivers.
- Worryingly, a literature survey and group discussions reveal that the increasing spread of non‐native fish species further compounds threats to mahseer and overall freshwater ecology. A better understanding of the current distribution, habitat requirement, and dispersal of non‐native fish is therefore essential to manage the growing threats to mahseer in the Indian Himalayan region.