scholarly journals Habitat use and population characteristics of potentially spawning shovelnose sturgeonScaphirhynchus platorynchus(Rafinesque, 1820), blue sucker (Cycleptus elongatus(Lesueur, 1817), and associated species in the lower Wisconsin River, USA

2016 ◽  
Vol 32 (6) ◽  
pp. 1003-1015 ◽  
Author(s):  
J. Lyons ◽  
D. Walchak ◽  
J. Haglund ◽  
P. Kanehl ◽  
B. Pracheil
2020 ◽  
Vol 3 (2) ◽  
pp. 83
Author(s):  
Ana María Sepúlveda-Seguro ◽  
Vivian Patricia Páez ◽  
Marley Tatiana Gómez-Rincón ◽  
Mónica A. Morales-Betancourt ◽  
Carlos A. Lasso

We conducted a short study in the Bojonawi Private Nature Reserve (Vichada department, Colombia) in three types of aquatic macrohabitats to characterize habitat use, population structure and reproductive phenology of Podocnemis vogli during one reproductive season. We also reevaluated the degree of sexual dimorphism in this species. To maximize capture rates, we used three methods: funnel traps, trammel nets, and manual capture. Only the funnel traps could be used in a standardized manner in all three macrohabitats. We captured 149 individuals in all age/size classes and obtained 11 recaptures. Since we were able to standardize sampling effort with the funnel traps in all macrohabitats, we compared habitat use and class structure among habitats during this reproductive season. There were no significant differences among the three macrohabitats in terms of relative abundances or size class distributions, but sex ratios differed, with an excess of males in the river and females in the lagoon. As with other congeners, P. vogli is a sexually dimorphic species where females attain larger sizes. In this study we documented that pre-cloacal tail length and nail length on the anterior third toe are the most useful secondary sexual characteristics for sexing subadult and adult individuals. Some females larger than 22 cm straight-line carapace length had calcified eggs in their oviducts. This species is abundant within the reserve and appears to be a habitat generalist, including the use of large rivers. More extensive and intensive monitoring is needed to document specific class survivorship rates, detectabilities and population dynamics.


2005 ◽  
Vol 56 (1) ◽  
pp. 37 ◽  
Author(s):  
Kerrylyn Johnston ◽  
Belinda J. Robson

The hymenosomatid crab Amarinus lacustris is abundant in some south-eastern Australian rivers; however, little is known of its ecology. Patterns of habitat use by crabs in rivers may be affected by seasonal changes in river discharge. This study investigates population characteristics, timing of reproduction and patterns of habitat use by A. lacustris in five riffle and pool habitats from each of the Hopkins and Merri Rivers in south-west Victoria, Australia, sampled over a twelve-month period. Distribution of Amarinus lacustris was similar between the two rivers, but log-linear modelling showed that there was a strong association between crab sex, habitat occupied and time of year because female A. lacustris showed a shift from riffle to pool habitats during March and April, coinciding with the non-gravid period of the year. Male crabs also showed a change in relative occurrence, occurring most often in riffles during winter–spring (July–November) but being equally common in both habitats in summer–autumn (January–May). These patterns are probably the result of the reproductive cycle of A. lacustris, which appears to show both ontogenetic and sex-related changes in habitat use during its life cycle, taking advantage of seasonal fluctuations in flow regime that may assist egg/larval development and dispersal.


2013 ◽  
Vol 97 (8) ◽  
pp. 939-953 ◽  
Author(s):  
Steven J. Starcevich ◽  
Stephanie L. Gunckel ◽  
Steven E. Jacobs

Author(s):  
Irena Bradinova ◽  
Silvia Andonova ◽  
Alexey Savov

AbstractPontocerebellar hypoplasia type 1B is a severe autosomal recessive neurologic disorder characterized by a combination of cerebellar and spinal motor neuron degeneration beginning at birth. Pontocerebellar hypoplasia type 1B is caused by mutations in EXOSC3 gene. High prevalence of the p.Gly31Ala mutation was found recently, especially in the Roma ethnic minority. We present a young Bulgarian Roma family with two deceased newborn children manifesting severe neuromuscular disorder including severe muscle weakness, respiratory distress, and multiple joint contractures. Based on the clinical signs and family's population characteristics, DNA testing for the previously described EXOSC3 in Bulgarian Roma mutation c.92G > C; p.Gly31Ala was performed on blood samples of both parents and they were found to be heterozygous carriers. This finding indirectly confirmed the diagnosis of pontocerebellar hypoplasia type B in the deceased offspring. Knowledge of population-specific molecular bases of genetic conditions was the key to final diagnosis in the presented family. Designing of population-based clinical-genetic panels may be a powerful diagnostic tool for patients with such origin. Preconception carrier screening in high-risk population groups is a feasible option to discuss.


2016 ◽  
Vol 544 ◽  
pp. 197-211 ◽  
Author(s):  
A Chin ◽  
MR Heupel ◽  
CA Simpfendorfer ◽  
AJ Tobin

2019 ◽  
Vol 609 ◽  
pp. 239-256 ◽  
Author(s):  
TL Silva ◽  
G Fay ◽  
TA Mooney ◽  
J Robbins ◽  
MT Weinrich ◽  
...  

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