High Mountain Streams Research Articles

High altitude mountain streams as a possible refuge habitat for the catfish Amphilius uranoscopus

Amphilius uranoscopus is a catfish species, restricted to rivers and streams in east, southern and central Africa. It is likely to be displaced due to both competition and predation by exotic trout and other introduced fish. In high altitude mountain streams it can be the only species occurring, which means that this habitat may act as a refuge for this species. Ecosystems like this are threatened by habitat alteration and are therefore in need of protection. The abiotic environment, population structure, behavior and feeding biology of Amphilius uranoscopus were studied in a small, high-altitude perennial tributary of the Limpopo River in the Soutpansberg mountain range, Limpopo Province, South Africa, during 2005–2006. Here A. uranoscopus showed nocturnal behavior. It used dark hollow crevices in rapids as shelters during the daytime. The rapids are characterized by a high flow rate, high dissolved oxygen content and coarse riverbed substrate consisting mainly of boulders without fallen leaves. In contrast to the adults, juveniles found shelter among the fallen leaves in pools. At night, A. uranoscopus moved out of the rapids into the open water of the pools. The main food of A. uranoscopus consisted of macroinvertebrates, mainly Trichoptera larvae. Amounts of algae and detritus in its diet were negligible. A. uranoscopus foraged mainly in rapids and on rock surfaces, spending less time foraging between the fallen leaves at the bottom of pools, in open water, at the surfaces of bottom and bank and near the water surface. At the water surface, it also fed opportunistically on terrestrial insects that dropped into the stream, like flying termites. A. uranoscopus was the top predator of the stream system and reached a high density (0.71 fish m−2). There was no competition from other fish species at the study site as they were lacking. A. uranoscopus showed a striking ability to climb and cling on to vertical substrates to conquer waterfalls and very shallow streams that sometimes become dry, using its fins, adhesive body and protruding mouth teeth.

Life history and larval feeding of some species of Ephemeroptera and Plecoptera (Insecta) in the Sierra Nevada (Southern Iberian Peninsula)

We monitored two high mountain streams from the Sierra Nevada (Southern Spain) monthly throughout an annual cycle, measuring and analyzing physical and chemical parameters. Temperature was hourly registered. We studied life cycles and larval feeding of four mayfly species [Serratella ignita (Poda, 1761), Serratella spinosa nevadensis (Alba-Tercedor, 1981), Alainites muticus (Linnaeus, 1758), and Baetis alpinus Pictet, 1843] and two stonefly species [Amphinemura triangularis (Ris, 1902) and Capnioneura mitis Despax, 1932]. Some species changed their strategies (growth rate, life cycle duration, and/or voltinism) in accordance with different conditions (depending on the altitude and temperature). The gut content data showed that species fed mainly on detritus (as collector-gatherers or as shredders), except B. alpinus that behaved as a scraper in one of the streams. Differences in the larval diet of the same species in different streams, and even through its life, support the idea of not using general models to extrapolate the function of a species from a higher taxonomical level.

Kryon - communities of high mountain streams

Kryon - communities of high mountain streams

Valuing the potential economic impact of climate change on the Taiwan trout

The purpose of this study is to estimate the value of the potential economic impact of climate change on the Taiwan trout (also referred to as Oncorhynchus masou formosanus), an endangered species that only lives in high mountain stream sections in which the water temperature is lower. A two-stage approach is adopted to estimate the value of the change in the Taiwan trout stock due to a change in climate. The first stage involves establishing the relationship between the Taiwan trout stock and climate change, while the second stage involves estimating the non-market value of the change in the Taiwan trout population using the double bound model associated with the contingent valuation method (CVM). Our results indicate that the total Taiwan trout population will decline from 1612 to 974, 560, and 146 if precipitation in Taiwan increases by 0.6 mm/day, while the temperature increases by 0.9 °C, 1.8 °C, and 2.7 °C, respectively. The mean willingness to pay per person per year to avoid a change in the trout stock caused by climate change is found to be US$16.22, US$25.72, and US$33.60, respectively.

Threatened fishes of the world: Kirikuchi charr, Salvelinus leucomaenis japonicus (Oshima 1961) (Salmonidae)

Common name: Kirikuchi (Japanese). Conservation status: Kirikuchi char (Salvelinus leucomaenis japonicus) is the southernmost population of the genus Salvelinus. Isolated from the main rivers in the drainages (Endangered, IUCN 1996; Threatened local populations, Tanaka 2003 Red Data Book of Japan 2003). Parts of the natural habitat have been designated as the natural protected area of Nara Prefecture. Identification: Kirikuchi char constitute geographically and genetically distinct local populations of Yamato char S. leucomaenis japonicus, a subspecies of the typical Japanese char S. leucomaenis leucomaenis, which belongs to a different clade of the Yamato char in a maximum parsimony tree of haplotypes (Yamamoto et al. 2004). Kirikuchi char differ morphologically from other Japanese chars: they have reddish golden bodies, few white spots on the lateral sides, darkish squash spots around the lateral lines, and relatively short snouts (Hosoya 2000). Photograph by Yuichi Kano. Distribution: Originally, Kirikuchi char were common in the Totsu and the Hidaka River systems in the Kii Peninsula, western Japan. However, only six small populations remain in the two upper drainages of the Totsu River system (34 5¢N, 135 33¢E; 34 13¢N, 135 53¢E), isolated from the main rivers in the drainages (Tanaka 2003, Sato & Watanabe 2004). Abundance: Its largest population comprises approximately 600 fish (100 mm and over in SL); the smallest, which might become extinct in the near future, comprises a few dozen individuals. Estimated effective population sizes of the largest two populations are not more than 100 individuals (Sato unpublished data). Habitat and ecology: Adapted to cold-water high mountain streams in which maximum temperatures are less than 18 C. Only the stream resident form has been observed. Specimens rarely reach 300 mm SL, and the average body size is approximately 160 –180 mm SL. Kirikuchi char preferably inhabit pools with refuges, woody debris and/or rocks, and feed mainly on aquatic and terrestrial insects. Reproduction: They spawn during October–November. Threats: Kirikuchi char face a high risk of extinction primarily from: (1) habitat deterioration by riparian forest logging or habitat fragmentation; (2) hybridization and competition with introduced non-native Nikko char S. leucomaenis pluvius, which has been commonly cultured and stocked in Japan; and (3) overharvesting, including poaching, by fishermen (Sato & Watanabe 2004). Moreover, because of their small isolated population structures, inbreeding depression might affect their viability. Conservation actions: Effective management measures have not been implemented, but a few volunteers are carrying out surveillance for prevention of poaching. Conservation education programs have also been launched for children of local communities. Conservation recommendations: Practical preservation techniques are urgently required for remaining populations. Habitat restoration, removal of non-native char, and re-establishment of new populations would be effective. Furthermore, rehabilitation of riparian forest is essential for conserving self-sustaining populations in the future. Remarks: Kirikuchi char is of biogeographical, evolutionary, and ecological interest.

Life Cycle of Himalopsyche japonica (Morton) (Trichoptera: Rhyacophilidae) in Two High Mountain Streams in Nagano, Central Japan

The life cycle of Himalopsyche japonica (Morton) was studied in two high mountain streams at about 1500 m a.s.l. from September 2000 to May 2002 in central Japan. The life cycles in both streams are univoltine. Larval development in upper streams with cooler water is slower than in lower streams with warmer water. The relationships between voltinism or larval size and water temperature are discussed.

Macroinvertebrates assemblages of high altitude lakes, inlets and outlets in the southern Alps

The invertebrate fauna of 21 high altitude lakes on the southern side of the Alps (Italy and Switzerland) were sampled once in the 1990 s. A total of 193 taxa was identified in 48 samples: 66 taxa were exclusive to the littoral zone, 17 to the outlets and 23 to the inlets. Chironomids prevailed in all environments with few exceptions. Inlets and littoral zones proved to be the richest habitats in number of taxa, while the littoral zones were richest in number of individuals. In all, 17,778 individuals were found in the Pennine-Lepontine Alps and 1966 in the Rhaetian ones. The number of taxa was 108 and 122, respectively. 69 taxa were exclusive to the former and 83 to the latter. Four groups of lakes have been distinguished by DCCA analysis applied to the littoral chironomid community. Water temperature, altitude, hydrochemistry, and lake area were the abiotic variables mostly related to chironomid distribution. Many steno-thermal species, typical of oligotrophic waters and high mountain streams were found, such as Zavrelimyia punctatissima, Diamesa latitarsis gr., Orthocladius frigidus, Prosimulium latimucro, Dictyogenus fontium, Baetis alpinus and Crenobia alpina. Only a few taxa such as D. fontium, Halesus radiatus, Plectrocnemia conspersa, Heterotris-socladius marcidus, Ablabesmyia sp., and Procladius sp. appeared to be tolerant to acidic conditions. These findings, as well as the rarity of molluscs, indicated that these environments are slightly acidic or at risk of acidification. Further studies on macroinvertebrates are required if they are to be used as possible indicators of local and global changes (e.g. acid deposition) in remote regions.

Larval diet of the frog Alsodes gargola (Leptodactylidae: Telmatobiinae) and some ecological considerations on its role in alpine and mountain aquatic environments in Patagonia

AbstractAlsodes gargola is an endemic species from northwest Patagonia, Argentina. Its tadpoles inhabit oligotrophic high altitude lakes and mountain streams from their sources. Tadpole diet is an important yet still unknown feature of its biology. This study analyzes alimentary tract content from A. gargola tadpoles collected from several of the species' typical habitats. For each group of items eaten, frequency of occurrence and its importance in the diet according to biovolume was calculated. Tadpole feeding behavior was also observed. The most common items were periphyton and plant material. The predominant algae were diatoms (typically periphytic), chlorophytes (periphytic and some planktonic) and a few cyanobacteria. Planktonic components were found in low proportion in all samples. The animal component (mainly from periphyton) was represented by ciliates, flagellates and amoebae, and varied according to the habitats, as did vascular plant fragments. There was a wide size range of ingested particles (from 10 to 400 μm) and a wide variety of components, according to the features of each habitat. These results suggest that tadpole of A. gargola are grazers of the periphytic community and detritus gatherers. The larval diet matches the tadpole's morphological and structural adaptations to a lotic-benthic habitat (depressed body, ventral subterminal oral disc capable of adherence, dorsal eyes, low, subparallel fins) and direct observation of behavior in natural environments (slow-swimming bottom-dwelling tadpoles in still water or streams with slow-flowing microhabitats). We discuss the ecological role of slow-developing tadpoles (regulation of periphyton development), which attain large biomass in their particular ecosystems, where they are the only aquatic vertebrates.

Microdistribution of chironomids (Diptera: Chironomidae) in Alpine streams: an autoecological perspective

Chironomid communities from three glacial and three non-glacial high mountain streams in three Alpine river basins were analyzed (Conca, Niscli, Cornisello, NE Italy, 46° N, 10° E). Eighteen sampling reaches belonging to five stream types (kryal, subkryal, glacio-rhithral, kreno-rhithral, outlet) were investigated. At each reach, geomorphological, physical, chemical and biological data were collected. Field surveys were carried out during three periods per year from 1996 to 1998: immediately after spring snowmelt, in mid-summer and in early autumn. In all, 439 zoobenthos samples were collected from 5 to 10 microhabitats of 0.1 m2 in each reach and date using a standard pond net (mesh size of 250 μm). About 50% of individuals collected were chironomids (26 673 specimens, 53 taxa), with densities ranging from 4 to 2652 ind m−2. With few exceptions, they dominated as number of taxa and individuals in all reaches. Chironomid subfamilies Diamesinae and Orthocladiinae were most abundant, especially in glacial reaches, where Diamesa spp. constituted up to 100% of the total fauna. Chironomid distribution was analyzed in relation to 37 abiotic variables, referring to stream origin, hydrology, geomorphology, physics and chemistry. Diamesa steinboecki, D. latitarsis gr. A and Pseudokiefferiella parva were the taxa best associated with ‘glacial’ conditions (i.e. high channel instability or presence of bedrock, high suspended solids and total phosphorous content, low conductivity and silica content, highly variable diel discharge and low mean temperature), while Pseudodiamesa branickii, Corynoneura spp., Eukiefferiella spp., Parorthocladius nudipennis, Tvetenia calvescens/bavarica, Thienemaniella spp. and Micropsectra atrofasciata were mostly associated with ‘non-glacial’ conditions. Substratum particle size, water depth, current velocity, the presence of riffles/pools and of mosses/algae (Hydrurus foetidus) were the major factors affecting microdistribution of chironomids in the investigated streams.

Are macroinvertebrates in high altitude streams affected by oxygen deficiency?

Summary1. The solubility of oxygen in water increases with decreasing temperature. This has led to a general perception of cold, high mountain streams as more oxygen rich than warmer lowland streams, and that macroinvertebrates inhabiting high altitude streams have had no need to adapt to critical oxygen conditions. However, this fails to take into account that oxygen solubility declines with decreasing atmospheric pressure, which may be of importance at high altitudes.2. Based on samples of macroinvertebrate benthos and in situ measurements of respiratory oxygen demand of macroinvertebrates in small streams from sea level to 4000 m a.s.l. in Ecuador, we determined predicted oxygen availability, oxygen demand and macroinvertebrate assemblage structure along this wide altitudinal gradient.3. We show that the predicted oxygen availability at 4000 m a.s.l. is only one fifth of that at sea level, whereas the mean weight‐specific respiratory rate of macroinvertebrates declined by only 50%, from 400 to 3800 m. We suggest that this disproportionately large gap between availability and demand of oxygen at high altitudes may imply a potential oxygen deficiency for the fauna, and we discuss how oxygen deficiency can be expected to affect macroinvertebrates in high altitude streams.4. Finally, we present preliminary data on the predicted response to oxygen deficiency of macroinvertebrate assemblages in high altitude streams. Compared with lowland streams, assemblages in natural high altitude streams include relatively few groups normally regarded as oxygen‐sensitive. Nevertheless, high altitude assemblages react more strongly to lowering of oxygen saturation, and are thus more sensitive to organic pollution.5. Oxygen deficiency has been overlooked completely in studies of the altitudinal distribution of species and aquatic communities. We argue that oxygen deficiency may be a potentially important factor, and that more focus on this topic is likely to produce significant new insights in aquatic community ecology.

Benthic Invertebrates and Metabolism of West Carpathian (Slovakia) Rivers

AbstractWe examined benthic invertebrates and metabolism on the basis of the annual sampling of 9 types of running waters in the West Carpathians. Headwaters in general represent typical heterotrophic systems, except where they are high mountain streams, which are autotrophic. Lower down, the upper reaches of brooks are transition zones between heterotrophic and autotrophic systems. After the transition to an autotrophic system (which depends mainly on the primary producers) there is a considerable decrease in secondary production. Production is higher in the rivers of the Carpathian basin, as well as lower down the valley (submontane rivers and lower tributaries of submontane streams) where, within the autotrophic systems, there is a shift of metabolism from the bottom to the water column. The temperature days, altitude and slope of the stream and concentration of calcium influence production of macrozoobenthos.

High-Mountain Lakes and Streams: Indicators of a Changing World

(2001). High-Mountain Lakes and Streams: Indicators of a Changing World. Arctic, Antarctic, and Alpine Research: Vol. 33, High Mountain Lakes and Streams: Indicators of the Changing World, pp. 383-384.

Geographic patterns of genetic and morphological divergence amongst populations of a river crab (Decapoda, Potamonautidae) with the description of a new species from mountain streams in the Western Cape, South Africa

Recent systematic research has revealed that Potamonautes brincki comprises two genetically and morphologically distinct population groups. The systematic affinities between these population groups have remained uncertain. In the present study, the relationship between the population groups was examined. Eleven populations were collected from high mountain streams in the Western Cape, South Africa and used in the genetic and morphological analyses. Allozyme electrophoresis of 13 protein coding loci separated two main population groups: group A (Cape Peninsular groups) and group B (Hottentot’s Holland) at I = 0.73. Two additional genetic groups were evident, with group B being conspecific to group A, and group D being conspecific to group C. Morphological examination of pleopod 1 and the terminal segment of the mandibular palp showed considerable differences between the two main population groups, with groups A and B being similar and groups C and D being similar. The morphometric data for the four main groups were examined using discriminant functions analysis and the two main groups were compared using analyses of covariance. Discriminant functions analysis showed a moderate degree of overlap between the groups. Additional morphometric data showed a clear discrimination between the two main population groups. The genetic and morphometric data sets exhibited congruent patterns of variation and the data showed the presence of a species boundary. A new freshwater crab species, P. parvicorpus sp. n., is described. The results of the present study are discussed in the light of historical and contemporary factors that are likely to have contributed to speciation.

Two New Harpellales Living in Ephemeroptera Nymphs in Colorado Rocky Mountain Streams

Two new species of harpellid gut fungi (Zygomycota: Trichomycetes) are described from the hindguts of mayfly nymphs inhabiting high altitude Rocky Mountain streams: the new genus and species Legeriosimilis tricaudata living in Ameletus sp. (Siphlonuridae), and the new species Glotzia coloradense from Baetis tricaudatus (Baetidae). Legeriomyces aenigmaticus is reported from a new site and a new ephemeropteran host, Ephemerella sp. (Ephemerellidae), and previously unknown zygospores are described.

Two new Harpellales living in Ephemeroptera nymphs in Colorado Rocky Mountain streams

Two new species of harpellid gut fungi (Zygomycota: Trichomycetes) are described from the hindguts of mayfly nymphs inhabiting high altitude Rocky Mountain streams: the new genus and species Legeriosimilis tricaudata living in Ameletus sp. (Siphlonuridae), and the new species Glotzia coloradense from Baetis tricaudatus (Baetidae). Legeriomyces aenigmaticus is reported from a new site and a new ephemeropteran host, Ephemerella sp. (Ephemerellidae), and previously unknown zygospores are described.

Colonization of aquatic macroinvertebrates in a high mountain stream using artificial substrates

Colonization of aquatic macroinvertebrates in a high mountain stream using artificial substrates

Use of biological assessment criteria in the evaluation of a high mountain stream, the Rio Hondo, New Mexico, USA

(1998). Use of biological assessment criteria in the evaluation of a high mountain stream, the Rio Hondo, New Mexico, USA. SIL Proceedings, 1922-2010: Vol. 26, No. 3, pp. 1227-1234.

Winter Stoneflies (Plecoptera) in Seasonal Habitats in New Mexico, USA

Seasonal stream habitats in New Mexico supported 10 species of winter-emerging stoneflies. Winter precipitation in combination with low winter temperatures created a seasonal moisture surplus and seasonal streamflow in this semi-arid region. Study area streams were dry for long periods in spring and autumn. Two different types of seasonal (ahyporheic) habitats were identified. Small high mountain streams fed by seasonal snowmelt runoff (type M) were inhabited by Capnia decepta, Eucapnopsis brevicauda, Isocapnia vedderensis, Capnia californica, Capnura wanica, Mesocapnia werneri, Taenionema jacobii, and Capnura fibula. Mesocapnia arizonensis and M. frisoni seemed to specialize in low-elevation watercourses fed by winter rains and rising water tables (type L). Adaptations for survival during spring and autumn periods of no streamflow, desiccation, or flash flooding include small size, rapid development, and diapause during egg or larval stages.

Use and partition of space and resources by two coexisting Rhyacophila species (Trichoptera) in a high mountain stream

Use and partition of space and resources by two coexisting Rhyacophila species (Trichoptera) in a high mountain stream

Benthic invertebrate fauna of an aseasonal tropical mountain stream on Bougainville Island, Papua New Guinea

The benthic invertebrate fauna of Konaiano Creek, a small aseasonal mountain rainforest stream on Bougainville Island, Papua New Guinea, was studied over a period of 22 months. Konaiano Creek supported a diverse, mostly undescribed, fauna dominated by two closely related species of Simuliidae (55% of the total specimens collected) and two species of Hydropsychidae. Over 182 taxa were recorded, more than half of which were Diptera. Species richness in Konaiano Creek was quite high in comparison with that of similar streams in both tropical and temperate regions. There were 31 species of Trichoptera, but there were no Plecoptera, Mollusca, Psephenidae, or Megaloptera. Although many groups of marine origin such as Gastropoda, Atyidae, Palaemonidae and fish inhabited nearby coastal rivers, these animals were apparently unable to colonize high mountain streams because of the torrential, barren nature of the mid-mountain streams that sharply divide the headwater streams from the lowland rivers on Bougainville Island.