scholarly journals The Amazonian dwarf cichlid Apistogramma agassizii (Steindachner, 1875) is a geographic mosaic of potentially tens of species: Conservation implications

2020 ◽  
Vol 30 (8) ◽  
pp. 1521-1539
Author(s):  
Guillain Estivals ◽  
Fabrice Duponchelle ◽  
Uwe Römer ◽  
Carmen García‐Dávila ◽  
Etienne Airola ◽  
...  
2012 ◽  
Vol 22 (3) ◽  
pp. 260-269 ◽  
Author(s):  
MUNIR Z. VIRANI ◽  
ARA MONADJEM ◽  
SIMON THOMSETT ◽  
CORINNE KENDALL

SummaryVulture populations have been declining globally and regionally within Africa. Rüppell’s Vulture Gyps rueppellii is currently listed as ‘Near Threatened’ and numbers of the species, along with African White-backed Vultures G. africanus, have declined by 52% in and around the Mara-Serengeti ecosystem. A large breeding colony of Rüppell’s Vulture at Kwenia, southern Kenya, was monitored between 2002 and 2009. Around 150–200 adults were present on each visit, with up to 64 simultaneously active nests. The date of egg-laying differed considerably between years, with two discrete breeding attempts in some years. Nests were not positioned randomly across the cliff face and the number of active nests was related to rainfall in the previous year. The large ungulate migration of the Mara-Serengeti provides a vital foraging ground for the species. Conservation implications of the loss of vultures are discussed.


2008 ◽  
Vol 18 (1) ◽  
pp. 20-29 ◽  
Author(s):  
Peter G. Ryan

AbstractIn addition to protecting species, conservation also includes the maintenance of evolutionary processes, but this aspect is often overlooked. Nesospiza buntings provide a good case study of the need to conserve evolutionary processes. They are endemic to the South Atlantic Tristan da Cunha archipelago, and traditionally have been treated as two species, with each having different subspecies on Nightingale and Inaccessible Islands. Both species are listed as Vulnerable because of their small ranges (<20 km2) and the threat posed by the possible introduction of alien organisms such as mice or rats. The two species differ markedly in size, especially bill size, related to dietary differences. However, recent research suggests that morphological diversity evolved independently on Nightingale and Inaccessible Islands, necessitating a revision of the taxonomy within the genus. I recommend that five taxa be recognized, with two endemic to Nightingale and three to Inaccessible Island. N. wilkinsi and N. questi on Nightingale are well-defined species, but there is considerable hybridization between taxa on Inaccessible Island. These three taxa may be incipient species, but are perhaps best treated as subspecies: N. acunhae acunhae, N. a. dunnei and N. a. fraseri (nom. nov.). All three species qualify as threatened, with N. acunhae and N. questi Vulnerable and N. wilkinsi Endangered. With fewer than 200 individuals, N. wilkinsi has one of the smallest natural populations of any bird. A reassessment of its population size is a conservation priority, following the 2001 storm that damaged many Phylica trees on Nightingale Island. Improved biosecurity quarantine measures are also needed for Nightingale Island. Care should be taken not to disrupt the natural processes occurring among bunting taxa on Inaccessible Island.


2021 ◽  
Vol 63 (3) ◽  
pp. 225-231
Author(s):  
Grażyna B. Dąbrowska ◽  
Henryk P. Dąbrowski ◽  
Iwona Szyp-Borowska

Abstract The natural range of the dwarf birch (Betula nana L.) includes the boreal, subarctic and arctic regions of Europe, Asia and North America, where it is relatively common. In Poland, it is a relict species occurring in fragmented populations. Using the random amplification of polymorphic DNA (RAPD) technique, we investigated the genetic diversity of the four Swedish populations representing a part of the continuous range of dwarf birch. With the knowledge of the level of genetic diversity of a population from a continuous distribution, we can assess the genetic status of polish populations and answer the question if habitat fragmentation and a decrease in population size lead to a loss in genetic diversity. Knowledge of genetic diversity is important for species conservation, especially to predict their ability to respond to environmental pressures. We found that the populations Abisko, Malbo, Gällivare and Storlien, which are located at the edge of the natural range of B. nana and occupy different habitats, are genetically diverse to varying degrees. The northern populations from Abisko and Gällivare showed a lower level of genetic polymorphism than the population from Malbo, the southernmost site of dwarf birch in Sweden. The data presented indicate higher genetic diversity existed within populations, whereas genetic differentiation between populations was lower. The high level of genetic differentiation within B. nana populations that were analysed in the present study may be explained by a limited capacity for dispersal among populations via both pollen and seeds. We found that the level of genetic diversity in one of the Polish populations of B. nana is comparable to that in areas in Scandinavia where populations are large and continuous. Based on these studies, we conclude that the “Linje” population has sufficient genetic resources.


Oryx ◽  
2018 ◽  
Vol 54 (2) ◽  
pp. 252-259 ◽  
Author(s):  
Brian Crudge ◽  
Trang Nguyen ◽  
Tien Trung Cao

AbstractLegalized trade in commercially farmed wildlife products is sometimes promoted as a conservation strategy. In theory, flooding the market with cheaper or better quality products will decrease the profitability of poaching. Bear bile is highly sought-after for use in traditional medicine and overhunting to supply the demand for bear parts has led to declining populations across South-east Asia. Bear bile farming was established to help supply the high demand for bear bile. In Viet Nam it is legal to keep registered bears, but illegal to extract or sell bear bile. We conducted semi-structured interviews with 66 bear bile farmers in Viet Nam to examine the conservation implications of bear bile farming. The results show that demand for wild bear bile was not satisfied by the widespread availability of farmed bear bile. Farmers report a strong consumer preference and willingness to pay more for wild-sourced products. The existence of bear bile farms presents considerable challenges to law enforcement. The results suggest that bear bile farming in Viet Nam relies on restocking from wild populations, and farmers openly admit to extracting and selling bear bile, in clear violation of national legislation. The case of bear bile farming in Viet Nam provides an example of wildlife farming failing to reduce pressure on a once widely distributed and relatively abundant species. Research into consumer values, attitudes and behaviours will help to improve understanding of market drivers and help inform the design of effective species conservation and management strategies.


EDIS ◽  
2017 ◽  
Vol 2017 (3) ◽  
Author(s):  
Shelly A. Johnson ◽  
Timm Kroeger ◽  
Josh Horn ◽  
Alison E. Adams ◽  
Damian C. Adams

Animals in Florida provide a variety of benefits to people, from recreation (fishing, hunting, or wildlife viewing) to protection of human life and property (oysters and corals provide reef structures that help protect coasts from erosion and flooding). By measuring the economic value of these benefits, we can assign a monetary value to the habitats that sustain these species and assess the value that is lost when development or other human-based activities degrade animal habitat. This 5-page fact sheet presents the results of a study that assessed the value of protecting five animal species in Florida and showed the economic value of protecting animal habitat.


2011 ◽  
Vol 29 (1-2) ◽  
pp. 10-12 ◽  
Author(s):  
T. N. Kaye ◽  
R. Schwindt ◽  
C. Menke

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kisei R. Tanaka ◽  
Kyle S. Van Houtan ◽  
Eric Mailander ◽  
Beatriz S. Dias ◽  
Carol Galginaitis ◽  
...  

AbstractDuring the 2014–2016 North Pacific marine heatwave, unprecedented sightings of juvenile white sharks (Carcharodon carcharias) emerged in central California. These records contradicted the species established life history, where juveniles remain in warmer waters in the southern California Current. This spatial shift is significant as it creates potential conflicts with commercial fisheries, protected species conservation, and public safety concerns. Here, we integrate community science, photogrammetry, biologging, and mesoscale climate data to describe and explain this phenomenon. We find a dramatic increase in white sharks from 2014 to 2019 in Monterey Bay that was overwhelmingly comprised of juvenile sharks < 2.5 m in total body length. Next, we derived thermal preferences from 22 million tag measurements of 14 juvenile sharks and use this to map the cold limit of their range. Consistent with historical records, the position of this cold edge averaged 34° N from 1982 to 2013 but jumped to 38.5° during the 2014–2016 marine heat wave. In addition to a poleward shift, thermally suitable habitat for juvenile sharks declined 223.2 km2 year−1 from 1982 to 2019 and was lowest in 2015 at the peak of the heatwave. In addition to advancing the adaptive management of this apex marine predator, we discuss this opportunity to engage public on climate change through marine megafauna.


Zygote ◽  
2021 ◽  
pp. 1-5
Author(s):  
Raquel Santos dos Santos ◽  
Jeane Rodrigues Rodrigues ◽  
Jhennifer Gomes Cordeiro ◽  
Hadda Tercya ◽  
Marissol Leite ◽  
...  

Summary This study describes the embryonic development of Moenkhausia oligolepis in laboratory conditions. After fertilization, the embryos were collected every 10 min up to 2 h, then every 20 min up to 4 h, and afterwards every 30 min until hatching. The fertilized eggs of M. oligolepis measured approximately 0.85 ± 0.5 mm and had an adhesive surface. Embryonic development lasted 14 h at 25ºC through the zygote, cleavage, blastula, gastrula, neurula, and segmentation phases. Hatching occurred in embryos around the 30-somites stage. The present results contribute only the second description of embryonic development to a species from the Moenkhausia genus, being also the first for this species. Such data are of paramount importance considering the current conflicting state of this genus phylogenetic classification and may help taxonomic studies. Understanding the biology of a species that is easily managed in laboratory conditions and has an ornamental appeal may assist studies in its reproduction to both supply the aquarium market and help the species conservation in nature. Moreover, these data enable the use of M. oligolepis as a model species in biotechnological applications, such as the germ cell transplantation approach.


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