scholarly journals Aquatic systems in and adjacent to Agulhas National Park with particular reference to the fish fauna

Koedoe ◽  
2006 ◽  
Vol 49 (2) ◽  
Author(s):  
I.A. Russell ◽  
N.D. Impson
Keyword(s):  
National Park ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Fish Fauna ◽  
Freshwater Fishes ◽  
Low Salinity ◽  
Management Actions ◽  
Physico Chemical ◽  
Species Being ◽  
Indigenous Fishes

The study aimed to determine the distribution and relative abundance of freshwater fishes in and adjacent to Agulhas National Park. Fourteen fish species were collected during surveys carried out in the Heuningnes and Ratel river systems and a variety of endorheic pans from 2003 to 2005. Seven of the species are marine fishes tolerant of low salinity (Mugil cephalus, Liza richardsonii, Monodactylus falciformis, Caffrogobius gilchristi, Rhabdosargus holubi, Solea bleekeri, Gilchristella aestuaria) with the remaining seven species being primary freshwater fishes. Three are indigenous, including Pseudobarbus burchelli, Sandelia capensis, and Galaxias zebratus of which two morphological forms were recorded within Agulhas National Park. The remaining four species are invasive aliens (Cyprinus carpio, Lepomis macrochirus, Micropterus salmoides, Micropterus punctulatus). Classification using physico-chemical variables indicated four major wetland groups, with fishes occurring predominantly in the group comprising palustrine, lacustrine and riverine wetlands, and in one instance in a brackish endorheic pan. Management actions which should facilitate conservation of indigenous fishes in the Agulhas region are suggested.

scholarly journals Freshwater fishes of Bontebok National Park

Koedoe ◽  
2001 ◽  
Vol 44 (2) ◽  
Author(s):  
I.A. Russell
Keyword(s):  
South African ◽  
National Park ◽  
Fish Assemblages ◽  
Micropterus Salmoides ◽  
Clarias Gariepinus ◽  
Lepomis Macrochirus ◽  
River System ◽  
Indigenous Species ◽  
Freshwater Species ◽  
Micropterus Dolomieu

Fish assemblages were sampled at six sites in the Breede River in the Bontebok National Park during 1999 and 2000. A total of 380 fish from 12 species was recorded. Indigenous fish collected included one freshwater species (Barbus andrewi), two catodromous species (Anguilla mossambica, Myxus capensis). and three estuarine species (Gilchris- tella aestuaria, Monodactylusfalciformis, Mugil cephalus). Four of the species recorded were aliens (Tinea tinea, Lepomis macrochirus, Micropterus salmoides, Micropterus dolomieu) and two species translocated from other South African rivers (Tilapia sparrmanii, Clarias gariepinus). A further two indigenous species (Sandelia capensis, Pseudobarbus biirchelli) could potentially occur within the park, though the high abundance of alien predators means that there is little chance for recolonisation from tributaries higher in the Breede River system. There is little opportunity to meaningfully conserve most indigenous freshwater fish in Bontebok National Park.

scholarly journals Freshwater fishes of Tsitsikamma National Park

Koedoe ◽  
2002 ◽  
Vol 45 (2) ◽  
Author(s):  
I.A. Russell
Keyword(s):  
National Park ◽  
Salmo Trutta ◽  
Fish Assemblages ◽  
Micropterus Salmoides ◽  
Freshwater Fishes ◽  
Cape Floristic Region ◽  
Indigenous Species ◽  
Freshwater Species ◽  
Alien Fish ◽  
Alien Fish Species

This study aimed to determine the distribution and relative abundance of freshwater fishes in the Tsitsikamma National Park. Fish assemblages in six river systems were sampled in 2001, with a total of 323 fish from eight species recorded. Indigenous fish collected included four freshwater species (Pseudobarbus afer, Pseudobarbus tenuis, Sandelia capensis, Anguilla mossambica), three estuarine species (Monodactylus falciformis, Caffrogobius gilchristi, Myxus capensis), and one alien (Micropterus salmoides). One additional indigenous species (Galaxias zebratus) and two aliens (Salmo trutta, Oncorhynchus mykiss) could potentially occur within the park. The topography and locality of the park presents a unique opportunity to meaningfully conserve the endangered P. tenuis as well as other fish characteristic of the eastern reaches of the Cape Floristic Region. Management action is required to minimise opportunities for further establishment and spread of alien fish species and to conserve indigenous fish assemblages within the park.

scholarly journals Freshwater fish of the Wilderness National Park

Koedoe ◽  
1999 ◽  
Vol 42 (1) ◽  
Author(s):  
I.A. Russell
Keyword(s):  
Freshwater Fish ◽  
National Park ◽  
Fish Assemblages ◽  
Micropterus Salmoides ◽  
Negative Influence ◽  
Catchment Management ◽  
Indigenous Species ◽  
Freshwater Species ◽  
Estuarine Species ◽  
Management Actions

The study aimed to determine the distribution and relative abundance of freshwater fish in the Wilderness National Park. Fish assemblages in the Touw and Duiwe rivers were sampled in 1997 and 1998, with a total of 327 fish from nine species recorded. Indigenous species included two freshwater species (Pseudobarbus afer, Sandelia capensis), two catadromous species (Anguilla mossambicus, Myxus capensis), and two estuarine species (Monodactylusfalciformis, Caffrogobius multifasciatus). Three of the nine recorded species were alien (Micropterus dolomieu, Micropterus salmoides, Gambusia affinis), with the Micropterus spp., in particular, likely to have a substantial negative influence on indigenous species. A further one indigenous species, two translocated indigenous species, and five estuarine species could potentially be recorded in these rivers. River catchment management actions to restore perennial flow to the Duiwe River, to prevent the attenuation of floods, and to prevent further establishment and spread of alien and translocated biota are required to conserve indigenous fish assemblages.

scholarly journals Freshwater fishes of Golden Gate Highlands National Park

Koedoe ◽  
2005 ◽  
Vol 48 (1) ◽  
Author(s):  
I.A. Russell ◽  
P.H. Skelton
Keyword(s):  
Oncorhynchus Mykiss ◽  
Alien Species ◽  
Relative Abundance ◽  
National Park ◽  
Freshwater Fishes ◽  
Indigenous Species ◽  
Golden Gate ◽  
Total Catch ◽  
Permanent Residents ◽  
Indigenous Fishes

The study aimed to determine the distribution and relative abundance of freshwater fishes in the Golden Gate Highlands National Park. A total of 1778 fish specimens from three species were collected during surveys carried out in the Little Caledon River during 2002. The chubbyhead barb Barbus anoplus was the only indigenous species recorded, and comprised 99.5 of the total catch. Two of the three recorded species were alien {Cypnnus carpio, Oncorhynchus mykiss}. A further nine indigenous species could potentially occur within the park, though are unlikely to be permanent residents. Barriers formed by instream impoundments may prevent temporary immigration of indigenous fishes, but also limit the further spread of alien species in the park's rivers.

scholarly journals Status, trends, and population demographics of selected sportfish species in the La Grange Reach of the Illinois River

2019 ◽  
Vol 42 ◽  
pp. 2019002 ◽  
Author(s):  
Levi Eric Solomon ◽  
Richard M Pendleton ◽  
Kristopher A Maxson ◽  
Daniel K Gibson-Reinemer ◽  
Cory A Anderson ◽  
...  
Keyword(s):  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Monitoring Program ◽  
Illinois River ◽  
Population Declines ◽  
Population Demographics ◽  
White Bass ◽  
Management Actions ◽  
Catch Rates

Abstract Sportfish species, specifically Yellow Bass Morone mississippiensis, White Bass Morone chrysops, Largemouth Bass Micropterus salmoides, Bluegill Lepomis macrochirus, Black Crappie Pomoxis nigromaculatus, and White Crappie P. annularis, often drive economically valuable fisheries in large river systems, including the Upper Mississippi River System (UMRS).  Within the Illinois River, part of the UMRS, these species are routinely sampled by an ongoing long-term fisheries monitoring program.  Through this program, we investigated long-term trends (1993-2017) in catch rates and relative weights and quantified demographic rates from 2012-2016. We found all six species, with the exception of Yellow Bass, to have declining catch rates with this decline being most stark in larger, older fishes.  Population demographics for Yellow Bass, White Bass, Bluegill, and Black Crappie suggest populations are dominated by younger individuals, with only Black Crappie regularly living to age 3 and older, which may be driving population declines.  There are many environmental stressors acting on the Illinois River that could be contributing to the lack of older and larger fishes, including, but not limited to, navigation efforts, altered hydrology, pollution, sedimentation, lack of overwintering habitat, and introduction of invasive species.  Results of this study demonstrate that additional research to understand mechanisms driving reduced abundance and stunted age structure are needed to identify effective management actions that would benefit populations of recreationally valuable sportfish species.

scholarly journals Distribution patterns of fish communities with respect to environmental gradients in Korean streams

2011 ◽  
Vol 47 ◽  
pp. S63-S71 ◽  
Author(s):  
Ju-Duk Yoon ◽  
Jeong-Hui Kim ◽  
Myeong-Seop Byeon ◽  
Hyung-Jae Yang ◽  
Jong-Young Park ◽  
...  
Keyword(s):  
Fish Species ◽  
Large Scale ◽  
Environmental Changes ◽  
Environmental Gradients ◽  
Anthropogenic Activities ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Fish Communities ◽  
Fish Fauna ◽  
Distribution Patterns

Stream development can generate environmental changes that impact fish communities. In temperate streams, the distribution of fish species is associated with environmental gradients. To analyze the relevant factors, large-scale exploration is required. Thus, to evaluate the distribution patterns of fish in Korea, sampling was conducted on a national scale at 720 sites over a 6-week period in 2009. A total of 124 fish species in 27 families were identified; Zacco platypus and Zacco koreanus of the Cyprinidae were the dominant and subdominant species, respectively. Of the species found, 46 (37.1%) were endemic and 4 (3.2%) exotic; of the latter, Micropterus salmoides and Lepomis macrochirus were widely distributed. Upon canonical correspondence analysis (CCA), both altitude and biological oxygen demand (BOD) were highly correlated with CCA axes 1 and 2, respectively. This explained 62.5% of the species–environment relationship. Altitude and stream order were longitudinally related to species distribution. The numbers of both total and endemic species gradually increased as streams grew in size to the fourth–fifth-order, and decreased in sixth-order, streams. Overall, fish communities were stable throughout the entire watershed, whereas some species showed site-specific occurrence patterns due to the paleogeomorphological characteristics of Korean peninsula. However, various anthropogenic activities may negatively affect fish communities. Therefore, both short- and long-term sustainable management strategies are required to conserve native fish fauna.

Mouth and Body Form Relative to Feeding Ecology in the Fish Fauna of a Small Lake, Lake Opinicon, Ontario

1966 ◽  
Vol 23 (12) ◽  
pp. 1845-1874 ◽  
Author(s):  
Allen Keast ◽  
Deirdre Webb
Keyword(s):  
Micropterus Salmoides ◽  
Habitat Preferences ◽  
Lepomis Macrochirus ◽  
Fish Fauna ◽  
Cylindrical Body ◽  
The Body ◽  
Pectoral Fins ◽  
Ictalurus Nebulosus ◽  
Wide Mouth ◽  
Basic Body

In 14 cohabiting fish species in a small freshwater lake, mouth and body structures combine with food specializations and habitat preferences to greatly restrict interspecific competition within the fauna.The species differ quantitatively in a large number of structures and, individually and in combination, these are clearly adapted for distinctive roles. The mouth is particularly plastic, varying in position, in aperture width, and in overall form, with structures as diverse as a scoop, a beak, and a tube being found. Six basic body types occur and these, combined with varying fin morphologies, result in a range of distinctive forms, including the following. Micropterus salmoides, with a compressed fusiform body and a wide mouth, is a strong-swimming, widely ranging piscivore. Notemigonus crysopterus, with a long, slender caudal peduncle, subfalcate pectoral fins, and a deeply forked caudal fin, has great maneuverability that permits it to catch individual zooplankters. Lepomis macrochirus is a "sedentary," gibbose-bodied water-hanger. Umbra limi has a stubby, cylindrical body that favours life in dense vegetation. Labidesthes sicculus, with an almost straight dorsal line to the body, a low dorsal fin, and a beak-like snout with tweezer-like teeth, is modified for surface feeding and leaping out of the water. Ictalurus nebulosus has chemotactile barbels that favour bottom feeding and paired fins that function partly as hydrofoils, keeping the body inclined downwards as the mouth sweeps the bottom.The structural specializations give their owners a decided ecological advantage in certain situations. Only a few species, however, are limited by them to restricted ways of life. In most cases, a considerable measure of feeding flexibility is retained, presumably important for survival in cold temperate lakes.

Managing rivers for conservation and ecotourism in the Kruger National Park

1995 ◽  
Vol 32 (5-6) ◽  
pp. 227-233 ◽  
Author(s):  
F. J. Venter ◽  
A. R. Deacon
Keyword(s):  
National Park ◽  
Good Condition ◽  
Kruger National Park ◽  
Rapid Expansion ◽  
Natural Environments ◽  
The West ◽  
The Past ◽  
Management Actions ◽  
Flow Through ◽  
Three Rivers

Six major rivers flow through the Kruger National Park (KNP). All these rivers originate outside and to the west of the KNP and are highly utilized. They are crucially important for the conservation of the unique natural environments of the KNP. The human population growth in the Lowveld during the past two decades brought with it the rapid expansion of irrigation farming, exotic afforestation and land grazed by domestic stock, as well as the establishment of large towns, mines, dams and industries. Along with these developments came overgrazing, erosion, over-utilization and pollution of rivers, as well as clearing of indigenous forests from large areas outside the borders of the KNP. Over-utilization of the rivers which ultimately flow through the KNP poses one of the most serious challenges to the KNP's management. This paper gives the background to the development in the catchments and highlights the problems which these have caused for the KNP. Management actions which have been taken as well as their results are discussed and solutions to certain problems proposed. Three rivers, namely the Letaba, Olifants and Sabie are respectively described as examples of an over-utilized river, a polluted river and a river which is still in a fairly good condition.

scholarly journals Effect of the Human Utilization of Northern Snakehead (Channa argus Cantor, 1842) on the Settlement of Exotic Fish and Cladoceran Community Structure

2021 ◽  
Vol 13 (5) ◽  
pp. 2486
Author(s):  
Jong-Yun Choi ◽  
Seong-Ki Kim
Keyword(s):  
Community Structure ◽  
Fish Species ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Nakdong River ◽  
Exotic Fish ◽  
Carnivorous Fish ◽  
Channa Argus ◽  
The Nakdong River ◽  
Exotic Fish Species

Empirical studies suggest that changes in the density of top predators, such as carnivorous fish, in freshwater food webs, strongly affect not only fish communities but also various primary and secondary consumers. Based on these findings, we explored how differences in the utilization of carnivorous fish (i.e., Northern Snakehead, Channa argus) by humans affected the fish and cladoceran community structure as well as the settlement of exotic fish species (i.e., Lepomis macrochirus and Micropterus salmoides) in 30 wetlands located in the upper and lower reaches of the Nakdong River. Our results show that in the mid–lower reaches of the Nakdong River, the density of C. argus was low, while high densities of L. macrochirus and M. salmoides were observed. Exotic fish species are frequently consumed by C. argus, leading to a low density of L. macrochirus and M. salmoides in the upper reaches, which supported a high density of C. argus. However, in the mid–lower reaches, the density of L. macrochirus was high because of the frequent collection of C. argus by fishing activities. The dominance of L. macrochirus significantly changed the structure of cladoceran communities. L. macrochirus mainly feeds on pelagic species, increasing the density of epiphytic species in the mid–lower reaches. The continued utilization of C. argus by humans induced a stable settlement of exotic fish species and strongly affected the community structures of primary consumers in the 30 wetlands. The frequency of C. argus collection has to be reduced to secure biodiversity in the mid–lower reaches of the Nakdong River, which will reduce the proportion of exotic fish species and increase the conservation of native fish.

Bridled Quail-dove Geotrygon mystacea population assessment after hurricanes Irma and Maria, St. Eustatius, Caribbean Netherlands

2021 ◽  
pp. 1-12
Author(s):  
FRANK F. RIVERA-MILÁN ◽  
HANNAH MADDEN ◽  
KEVIN VERDEL
Keyword(s):  
National Park ◽  
Food Limitation ◽  
Distance Sampling ◽  
Population Status ◽  
Management Actions ◽  
Abundance Estimates ◽  
Detection Mode ◽  
Limited Food ◽  
Seed Eating ◽  
Free Ranging

Summary Structural vegetation damage and food limitation are important effects of major hurricanes, particularly for fruit/seed-eating, forest-dependent Caribbean birds with restricted distributions and small populations, such as the Bridled Quail-dove Geotrygon mystacea. Motivated by the lack of abundance estimates, corrected for detection probability, we conducted distance-sampling surveys inside and outside the Quill National Park each May in 2016-2019. Detection mode was the most important covariate, with others receiving no support from the data. Detectability of available single individuals and clusters of individuals within 60 m of transect centrelines averaged 0.957 ± 0.114 standard error for audio detections, 0.434 ± 0.052 for visual detections, and 0.693 ± 0.064 for detection modes combined. Availability averaged 0.475 ± 0.138 and the product of detectability and availability averaged 0.329 ± 0.098. Density averaged 1.459 ± 0.277 individuals ha-1 and population size averaged 642 ± 122 individuals in 440 ha. Density did not differ along and away from forest trails, but was higher inside than outside the park and at elevations within 201-400 m than 100-200 m and 401-600 m. Density declined by 76% after hurricanes Irma and Maria in 2017. We suggest that major hurricanes together with free-ranging livestock overgrazing degraded foraging habitats, limited food supply, and caused a population bottleneck. Our methodology can be implemented across the distribution range to assess population status and trends and evaluate the result of management actions at key conservation sites. Bridled Quail-dove populations probably were declining on most islands before the 2017 hurricanes and population status warrants revision.

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