scholarly journals Diversity and Abundance of Zooplankton in River Aswa in Uganda

2021 ◽  
Vol 19 (2) ◽  
pp. 35-45
Author(s):  
Vincent Kiggundu ◽  
Samuel Vivian Mataagi ◽  
Lucas Mwebaza Ndawula ◽  
William Okello

Zooplankton community constitutes one of the keystone organisms that are crucial in understanding aquatic ecosystem responses to environmental distresses. The objective of this study was to contribute to the understanding of zooplankton ecological conservation status and assessment of potential impacts of the proposed Hydropower plant on the zooplankton community in River Aswa, Nwoya District, in Uganda. Baseline information on aquatic micro-invertebrate diversity, abundance and distribution along the affected river section was generated. Two copepods and four species of rotifers were recorded. The Intake site had the highest diversity (six species) while Powerhouse hadfour species. Of the species encountered, Keratella tropica registered the highest abundance—1,025 and 732 individuals m-2 at the Powerhouse and Intake sites, respectively. Total zooplankton densities were comparable with Intake (2,773 individuals m-2) and Powerhouse (2,311 individuals m-2). The zooplankton taxa do not appear in the IUCN Red List in the Catalogue of Life. Therefore, the proposed construction of a hydropower plant may not pose zooplankton conservation problems. Keywords: Biodiversity, Zooplankton, invertebrates, hydropower, River Aswa.

Oryx ◽  
2020 ◽  
pp. 1-4
Author(s):  
Germán Garrote ◽  
Beyker Castañeda ◽  
Jose Manuel Escobar ◽  
Laura Pérez ◽  
Brayan Marín ◽  
...  

Abstract The giant otter Pteronura brasiliensis, categorized as Endangered on the IUCN Red List, was once widely distributed throughout South America. By the middle of the 20th century the giant otter had become locally extinct along the main rivers of the Orinoco basin. Although some populations seem to have recovered, the paucity of information available does not permit a full evaluation of the species' conservation status. The objective of this study was to estimate the abundance and density of the giant otter population along the Orinoco river in the municipality of Puerto Carreño, Vichada, Colombia, where there is important commercial and recreational fishing. Thirty-nine linear km were surveyed, repeatedly, with a total of 315 km of surveys. Population size was estimated by direct counts of individuals. All individuals detected were photographed and identified individually from their throat pelage patterns. In total, 30 otters were identified, giving a minimum density of 0.77 individuals per km, one of the highest reported for the species in Colombia. Given the high density in this well-developed area, our results highlight the importance of this population for the conservation of the species.


Oryx ◽  
2021 ◽  
pp. 1-10
Author(s):  
Riley A. Pollom ◽  
Gina M. Ralph ◽  
Caroline M. Pollock ◽  
Amanda C.J. Vincent

Abstract Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are seahorses (Hippocampus spp.: 14/42 species, with an additional 17 that are Data Deficient) or freshwater pipefishes of the genus Microphis (2/18 species, with seven additional that are Data Deficient). Two species are Near Threatened. Nearly one-third of syngnathiformes (97 species) are Data Deficient and could potentially be threatened, requiring further field research and evaluation. Most species (61%) were, however, evaluated as Least Concern. Primary threats to syngnathids are (1) overexploitation, primarily by non-selective fisheries, for which most assessments were determined by criterion A (Hippocampus) and/or (2) habitat loss and degradation, for which assessments were determined by criterion B (Microphis and some Hippocampus). Threatened species occurred in most regions but more are found in East and South-east Asia and in South African estuaries. Vital conservation action for syngnathids, including constraining fisheries, particularly non-selective extraction, and habitat protection and rehabilitation, will benefit many other aquatic species.


Oryx ◽  
2020 ◽  
pp. 1-6
Author(s):  
María M. Torres-Martínez ◽  
Héctor E. Ramírez-Chaves ◽  
Elkin A. Noguera-Urbano ◽  
Fernando C. Passos

Abstract The brown hairy dwarf porcupine Coendou vestitus is a poorly studied Andean species endemic to Colombia. Its current Red List category is contradictory: globally it is categorized as Data Deficient but in Colombia it is categorized as Vulnerable. This contradiction has limited the implementation of conservation programmes. We evaluate the level of rarity of the species and provide consolidated information for a new assessment of its Red List status. We reviewed literature, photographs, and voucher specimens in natural history collections. Using the confirmed records, we estimated the extent of occurrence (EOO) based on the minimum convex polygon and the area of occupancy (AOO) summing the area of grid squares occupied by the species. We found that C. vestitus is very rare, with a small range, low estimated population density, occurrence in only one habitat type and small body size. The species has an EOO of 3,323 km2 and an AOO of 24 km2, based on six confirmed localities, all on the western slopes of the Eastern Cordillera, in the central Andean region of Colombia. Based on the species' rarity, restricted distribution, and threats to its natural habitat, we recommend its categorization as Endangered on the IUCN Red List. This will help delineate research and conservation efforts for this porcupine, which has a highly restricted range and inhabits the threatened Andean forest.


2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Beth A. Polidoro ◽  
Cristiane T. Elfes ◽  
Jonnell C. Sanciangco ◽  
Helen Pippard ◽  
Kent E. Carpenter

Given the economic and cultural dependence on the marine environment in Oceania and a rapidly expanding human population, many marine species populations are in decline and may be vulnerable to extinction from a number of local and regional threats. IUCN Red List assessments, a widely used system for quantifying threats to species and assessing species extinction risk, have been completed for 1190 marine species in Oceania to date, including all known species of corals, mangroves, seagrasses, sea snakes, marine mammals, sea birds, sea turtles, sharks, and rays present in Oceania, plus all species in five important perciform fish groups. Many of the species in these groups are threatened by the modification or destruction of coastal habitats, overfishing from direct or indirect exploitation, pollution, and other ecological or environmental changes associated with climate change. Spatial analyses of threatened species highlight priority areas for both site- and species-specific conservation action. Although increased knowledge and use of newly available IUCN Red List assessments for marine species can greatly improve conservation priorities for marine species in Oceania, many important fish groups are still in urgent need of assessment.


Oryx ◽  
2014 ◽  
Vol 49 (1) ◽  
pp. 107-110 ◽  
Author(s):  
Lajos Rózsa ◽  
Zoltán Vas

AbstractThe co-extinction of parasitic taxa and their host species is considered a common phenomenon in the current global extinction crisis. However, information about the conservation status of parasitic taxa is scarce. We present a global list of co-extinct and critically co-endangered parasitic lice (Phthiraptera), based on published data on their host-specificity and their hosts’ conservation status according to the IUCN Red List. We list six co-extinct and 40 (possibly 41) critically co-endangered species. Additionally, we recognize 2–4 species that went extinct as a result of conservation efforts to save their hosts. Conservationists should consider preserving host-specific lice as part of their efforts to save species.


Oryx ◽  
2006 ◽  
Vol 40 (2) ◽  
pp. 183-188 ◽  
Author(s):  
Walter J. Reisinger ◽  
Devi M. Stuart-Fox ◽  
Barend F.N. Erasmus

We quantified habitat associations and evaluated the conservation status of a recently identified, undescribed species of dwarf chameleon, Bradypodion sp. nov. Dhlinza, endemic to scarp forest remnants in KwaZulu-Natal Province, South Africa. At the microhabitat scale the Dhlinza dwarf chameleon was found more often in forest gaps and near paths than highly disturbed edges or forest interior. Chameleon presence was not explained by forest physiognomic variables such as vine cover, shrub and tree density, or canopy cover. Presence near gaps may be better explained by the combined effects of the thermal microenvironment and food availability. The species is moderately common where it occurs, with estimated densities of 4.7, 8.7 and 29.7 individuals per ha within forest interior, edges and gaps respectively. At the landscape scale, the chameleon occurs only in three remnant forests: the Dhlinza, Entumeni and Ongoye Forests. The species' extent of occurrence was estimated to be 88 km2 and its area of occupancy 49 km2. Based on the small area of remaining suitable habitat, this species meets the requirements for categorization as Endangered according to IUCN Red List criteria.


Phytotaxa ◽  
2018 ◽  
Vol 373 (2) ◽  
pp. 99
Author(s):  
PASCAL DESCOURVIÈRES ◽  
JOÃO N. M. FARMINHÃO ◽  
VINCENT DROISSART ◽  
JEAN-YVES DUBUISSON ◽  
MURIELLE SIMO-DROISSART ◽  
...  

A recent large phylogenetic tree for the angraecoid orchids has shown that the Afrotropical genus Diaphananthe is polyphyletic with a small group of four species sister to Aerangis and Eurychone. These species have diagnostic morphological features different from any other angraecoids, notably an erose to fringed surface of the stipes and a calceiform viscidium. Diaphananthe quintasii, which has been regarded as conspecific with D. rohrii, is reinstated as a valid species and lectotypified, and Diaphananthe alfredii and Rhipidoglossum magnicalcar are put in synonymy under D. quintasii. To accommodate this group of species, along with three new taxa from West and Central Africa, a new genus named Kylicanthe is here described. Four new combinations are thus proposed, and K. bueae is chosen as the type species of the new genus and neotypified. Additionally, K. arcuata, K. cornuata, and K. perezverae are described as new species. An identification key for Kylicanthe and allied genera is presented, as well as one for the seven species in the genus. Notes on ecology and distribution in addition to a preliminary assessment of conservation status following the IUCN Red List are also provided.


2020 ◽  
Vol 21 (8) ◽  
Author(s):  
Iyan Robiansyah ◽  
Wita Wardani

Abstract. Robiansyah I, Wardani W. 2020. Increasing accuracy: The advantage of using open access species occurrence database in the Red List assessment. Biodiversitas 21: 3658-3664. IUCN Red List is the most widely used instrument to assess and advise the extinction risk of a species. One of the criteria used in IUCN Red List is geographical range of the species assessed (criterion B) in the form of extent of occurrence (EOO) and/or area of occupancy (AOO). While this criterion is presumed to be the easiest to be completed as it is based mainly on species occurrence data, there are some assessments that failed to maximize freely available databases. Here, we reassessed the conservation status of Cibotium arachnoideum, a tree fern distributed in Sumatra and Borneo. This species was previously assessed by Praptosuwiryo (2020, Biodiversitas 21 (4): 1379-1384) which classified the species as Endangered (EN) under criteria B2ab(i,ii,iii); C2a(ii). Using additional data from herbarium specimens recorded in the Global Biodiversity Information Facility (GBIF) website and from peer-reviewed scientific papers, in the present paper we show that C. arachnoideum has a larger extent of occurrence (EOO) and area of occupancy (AOO), more locations and different conservation status compared to those in Praptosuwiryo (2020). Our results are supported by the predicted suitable habitat map of C. arachnoideum produced by MaxEnt modelling method. Based on our assessment, we propose the category of Vulnerable (VU) C2a(i) as the global conservation status for C. arachnoideum. Our study implies the advantage of using open access databases to increase the accuracy of extinction risk assessment under the IUCN Red List criteria in regions like Indonesia, where adequate taxonomical information is not always readily available.


2018 ◽  
Vol 6 ◽  
pp. 31-44 ◽  
Author(s):  
Giuseppe Fenu ◽  
Mohamed Abdelaal ◽  
Gianluigi Bacchetta ◽  
Luciano Bongiorni ◽  
Annalena Cogoni ◽  
...  

In this contribution, the conservation status assessment of four vascular plants according to IUCN categories and criteria are presented. It includes the assessment ofEpipactismaricae(Croce, Bongiorni, De Vivo & Fori) Presser & S.Hertel at global level, and the regional assessment ofCerintheretortaSm. (Italy), PlatantherakuenkeleiH.Baumannsubsp.kuenkelei (Europe) andTyphaelephantinaRoxb. (Egypt).


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