scholarly journals Conservation status revision and communities’ perceptions of 22 Aloe species in Tanzania

2021 ◽  
Vol 154 (3) ◽  
pp. 391-404
Author(s):  
Siri A. Abihudi ◽  
Hugo J. De Boer ◽  
Anna C. Treydte

Background and aims – Many Aloe species are globally threatened due to overharvesting for trade and habitat destruction. CITES regulates their international trade. In Tanzania, 50% of all existing Aloe species had previously been assessed, though some of these assessments were Data Deficient. For those with sufficient data, an update is required as the rate of decline has rapidly increased over the last years. Material and methods – We estimated Area of Occupancy (AOO), Extent of Occurrence (EOO), and number of locations for 22 Tanzanian Aloe species using the Geospatial Conservation Assessment software (GeoCAT). We assessed the reasons leading to their decline based on direct field observations and community perceptions. Key results – We revised the conservation status of 22 Aloe species; two were assessed as Critically Endangered, ten as Endangered, five as Vulnerable, and five as Least Concern. We re-discovered the Critically Endangered Aloe boscawenii, which had not been seen in Tanzania for more than six decades. We propose to downgrade the endemic Aloe dorotheae, Aloe leptosiphon, and Aloe flexilifolia from Critically Endangered to a lower threat level. The community perception on Aloe species availability did not accurately reflect their categorisation based on the IUCN criteria B. We identified agricultural activities and climate change effects as the two main threats to Tanzanian Aloe species.Conclusion – We conclude that overall numbers are declining for 22 Aloe species in Tanzania, mainly due to human activities. We recommend the implementation of laws and policies to protect their natural habitats.

Hacquetia ◽  
2020 ◽  
Vol 19 (2) ◽  
pp. 307-315
Author(s):  
Ümit Subaşı ◽  
Fatoş Şekerciler ◽  
Mecit Vural

AbstractLotus sanguineus is one of the endemic taxa from Mediterranean Region of Turkey. It has hitherto been known from type locality and was assessed under VU and EN categories despite the lack of information on the population size, number of location and habitat quality. This study aims to determine the global conservation status and conservation strategies of the narrow endemic species. We collected all available data and evaluated them with the field studies. We reported the sizes of populations, altitude, coordinates, habitat types and the threats it faces for each locality. GeoCAT analyses at global levels indicate the extent of occurrence 19.965 km2 and area of occupancy 9 km2 and there could be an inferred decline due to habitat loss and fragmentation of the original population, suggesting this species might be classified as Critically Endangered, based on criterium B1ab (i, ii, iii) + 2ab (i, ii, iii) in the Red List categorization. Conservation priorities include life history and ecology studies, in-situ conservation, population monitoring and ex-situ conservation to prevent the destruction of the existing gene pool.


2019 ◽  
Vol 41 (3) ◽  
Author(s):  
Dao Nhan Loi

Son La is a well-known city in the Northwestern region of Vietnam for its outstanding landscapes. It contains a variety of ecosystems ranging from farming area, valleys, forests on hills and karst with cave systems. Natural habitats of the city would be suitable for many bat species. However, bats of the city were not included in any literature. Between March 2014 and June 2018, we conducted a series of bat surveys in this city using mist nets and harp traps. Results from our study indicated that Son La city is a home to at least 21 bat species belonging to 9 genera, 6 families. Of which, Rhinolophus thomasi was listed as “VU” (Vulnerable) in the 2007 Red Book of Vietnam and Myotis annamiticus was listed in the IUCN Redlist of the Threatened Species as “DD” (Data Deficient). This paper provides the first data on bats of Son La city with morphological measurements and conservation status of each recorded species.


Diversity ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 150
Author(s):  
Marcos R. Bornschein ◽  
Marcio R. Pie ◽  
Larissa Teixeira

The number of described anurans has increased continuously, with many newly described species determined to be at risk. Most of these new species inhabit hotspots and are under threat of habitat loss, such as Brachycephalus, a genus of small toadlets that inhabits the litter of the Brazilian Atlantic Rainforest. Of 36 known species, 22 were described in the last decade, but only 11 have been assessed according to the IUCN Red List categories, with just one currently listed as Critically Endangered. All available data on occurrence, distribution, density, and threats to Brachycephalus were reviewed. The species extent of occurrence was estimated using the Minimum Convex Polygon method for species with three or more records and by delimiting continuous areas within the altitudinal range of species with up to two records. These data were integrated to assess the conservation status according to the IUCN criteria. Six species have been evaluated as Critically Endangered, five as Endangered, 10 as Vulnerable, five as Least Concern, and 10 as Data Deficient. Deforestation was the most common threat to imperiled Brachycephalus species. The official recognition of these categories might be more readily adopted if the microendemic nature of their geographical distribution is taken into account.


2006 ◽  
Vol 12 (2) ◽  
pp. 134 ◽  
Author(s):  
David M. J. S. Bowman ◽  
Daniel L McIntyre ◽  
Barry W. Brook

The Carpentarian Rock-rat Zyzomys palatalis is a rare conilurine rodent with a global distribution restricted to a small area of sandstone escarpments in the Gulf of Carpentaria region of the Northern Territory. Previous assessments of its World Conservation Union (IUCN) status in 1996 had classified the species as Critically Endangered based on the restricted area of occupancy and a putative decline in the extent and quality of its closed forest habitat due to uncontrolled landscape fires. A later population viability analysis confirmed that habitat loss was potentially the single most important threatening process. Here we argue that the species should be reclassified as Vulnerable, on the basis of the following new evidence: (1) the assumption that it was a closed forest specialist was not supported by a radiotracking study, which showed that on average 43% of an individual's monitored time was spent in the forest-savannah margin, and (2) analysis of repeat historical aerial photography has shown that the core closed forest habitat has in fact increased by 36% over the last 50 years. This has lead to an increase of 140 in the minimum number of equivalent Z. paJatalis territories, from 387 to 587, when home range overlaps and utilization of the savannah margins are considered. Reclassification of the species' conservation status should be accompanied with: (i) genetic studies of relatedness between isolated populations; (ii) monitoring and maintenance of the integrity of the landscapes, including creeklines that connect patches; and (iii) consideration of the introduction of captive bred specimens into an adjacent unoccupied fragments.


Oryx ◽  
2011 ◽  
Vol 45 (3) ◽  
pp. 439-443 ◽  
Author(s):  
Rodrigo C. Printes ◽  
Anthony B. Rylands ◽  
Júlio César Bicca-Marques

AbstractThe blond titi monkey Callicebus barbarabrownae lives in forest fragments in the caatinga (tropical thorn scrub and forest) of north-east Brazil. In 2004–2005 we carried out five surveys to determine its current distribution and conservation status; surveying forest fragments, interviewing local people, and recording vegetation types and patterns of land use. The blond titi monkey occurs mainly in Dense Arboreal Caatinga and Highland Coastal Rainforest in the state of Bahia, at elevations of 241–908 m. Its range extends over 291,438 km2, with an area of occupancy of 2,636 km2. Estimated minimum population was 260 individuals. It was not recorded in any protected area. Cattle ranching favours the persistence of forest fragments for this species, whereas agriculture, subsistence or commercial, does not. Our findings supported the IUCN Red List assessment of Critically Endangered for this species.


2018 ◽  
Vol 10 (8) ◽  
pp. 12056
Author(s):  
Kersley Bruno Pynee ◽  
David Harold Lorence ◽  
Poojanraj Khurun

Aerva congesta Balf.f. ex Baker (Amaranthaceae), an endemic of Mascarene Islands (Mauritius and Rodrigues) is assessed for its conservation status. Considering its local extinction in Rodrigues and very small population in Mauritius, in Round Island and at Gris Gris, south of Mauritius its area of occupancy (AOO) is estimated at 8km².  Due to its small AOO and threats by increasing native vegetation and alien species, A. congesta is evaluated as Critically Endangered following the latest IUCN Red List criteria.  The species needs an urgent well-defined restoration program and ecological studies to prevent its extinction.  


2020 ◽  
Vol 26 (2) ◽  
pp. 150
Author(s):  
W. Goulding ◽  
P. Moss ◽  
C. A. McAlpine

The Tagula butcherbird (Cracticus louisiadensis) is an endemic island species of butcherbird that has remained virtually unknown for over 130 years. The lack of information on the species has resulted in it being assigned to the Data Deficient category by BirdLife International and the IUCN, leaving its conservation status open to continuing speculation. This is an ongoing concern given the rapid environmental changes occurring in the region. Here, we describe the first observations of the habitat use, life history and ecology of the species. We also present information collected across the island distribution of the species, including density and population estimates. We found the Tagula butcherbird to be culturally important and relatively common in suitable habitats across four islands of the Louisiade Archipelago (Papua New Guinea). However, the species was absent from highly disturbed areas. We estimated this species’ extent of occurrence to be ~1200km2 and area of occupancy to be less than 800km2. Population densities were estimated via pre-dawn assessments of singing birds and line transects. Density estimates were found to be between 0.14 and 0.53 individuals per hectare, with the highest density observed on Sabara Island. These densities were combined with remote sensing data to estimate the amount of available habitat and the species’ population size, which was estimated to be between ~11500 and 23000 individuals. The species’ dependence on forest habitat with a relatively intact canopy, combined with the likely continuing destruction of habitat on Junet and Panawina Islands, remains a conservation concern.


Oryx ◽  
2007 ◽  
Vol 41 (3) ◽  
pp. 300-305 ◽  
Author(s):  
Scott Zona ◽  
Raúl Verdecia ◽  
Angela Leiva Sánchez ◽  
Carl E. Lewis ◽  
Mike Maunder

AbstractThe conservation status of 134 species, subspecies and varieties of West Indian palms (Arecaceae) is assessed and reviewed, based on field studies and current literature. We find that 90% of the palm taxa of the West Indies are endemic. Using the IUCN Red List categories one species is categorized as Extinct, 11 taxa as Critically Endangered, 19 as Endangered, and 21 as Vulnerable. Fifty-seven taxa are classified as Least Concern. Twenty-five taxa are Data Deficient, an indication that additional field studies are urgently needed. The 11 Critically Endangered taxa warrant immediate conservation action; some are currently the subject of ex situ and in situ conservation projects in the region’s botanical gardens. We recommend that preliminary conservation assessments be made of the 25 Data Deficient taxa so that conservation measures can be implemented for those facing imminent threats.


2011 ◽  
Vol 21 (4) ◽  
pp. 477-489 ◽  
Author(s):  
RICARDO S. CEIA ◽  
JAIME A. RAMOS ◽  
RUBEN H. HELENO ◽  
GEOFF M. HILTON ◽  
TIAGO A. MARQUES

SummaryThe Azores Bullfinch is endemic to the island of São Miguel (Azores, Portugal). Its status was uplisted to Critically Endangered in 2005 on the basis of an extremely small and declining population that was considered to be restricted to a very small mountain range (43 km2), in a single location, within which the spread of invasive plants constituted a threat to habitat quality. Nevertheless, information was mostly inferred, or the product of, non-systematic studies. In order to carry out a complete assessment of the conservation status we analysed: (i) population trend, calculated from annual monitoring 1991–2008, (ii) population size, and (iii) range size, obtaining estimates in a single morning study in 2008 involving the simultaneous participation of 48 observers. Contrary to previous inferences, the population is no longer decreasing, although quality of laurel forest habitat continues to decline due to the persistent threat of invasive species. Population size (mean ± SE) was estimated at 1,064 ± 304 individuals using distance sampling methods, although the estimate was very sensitive to the survey method used. Range size estimates (extent of occurrence and area of occupancy) were 144 km2 and 83 km2 respectively. Given the present information, we propose the downlisting of Azores Bullfinch to Endangered on the IUCN Red List.


2010 ◽  
Vol 100 (1) ◽  
pp. 05-12 ◽  
Author(s):  
Andrés Canavero ◽  
Santiago Carreira ◽  
José A. Langone ◽  
Federico Achaval ◽  
Claudio Borteiro ◽  
...  

The native species of amphibians and reptiles of Uruguay were categorized according to the IUCN Red List criteria. Out of 47 amphibian species, seven are listed as Critically Endangered (CR), five as Endangered (EN), one as Vulnerable (VU), three as Near Threatened (NT), and two as Data Deficient (DD); the remaining species are considered to be Least Concern (LC). Among the 64 species of reptiles evaluated, one is listed as Critically Endangered (CR), seven as Endangered (EN), two as Vulnerable (VU), one as Near Threatened (NT) and seven as Data Deficient (DD); the rest are considered to be Least Concern (LC). The use of these results as an additional criterion in the definition of protected areas in Uruguay will contribute towards the conservation of the aforementioned threatened species and their associated ecosystems.


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