Aspects of reproductive biology of the humpback smooth-hound shark (Mustelus whitneyi) off northern Peru

2019 ◽  
Vol 70 (8) ◽  
pp. 1185 ◽  
Author(s):  
Adriana Gonzalez-Pestana ◽  
Joanna Alfaro-Shigueto ◽  
Jeffrey C. Mangel

The humpback smooth-hound shark (Mustelus whitneyi) is one of the most captured shark species in the south-east Pacific and is classified as vulnerable, yet its reproductive biology has been poorly studied. The aim of this study was to increase our knowledge of the reproductive biology of the humpback smooth-hound shark. In all, 41 pregnant females, 386 macroscopically visible embryos in utero and 16 neonates were sampled off northern Peru. Pregnant females measured between 73- and 118-cm total length (TL) and the number of embryos per litter ranged from 6 to 18, with a mean of 10. Size at birth ranged between 21 and 22cm TL. Litter size increased with the TL of the mother, yet this relationship was not strong (r2=0.36). The gestation period had a minimum duration of 7 months and a synchronous cycle in which birth occurred in September. The humpback smooth-hound shark is a placental viviparous elasmobranch. This study represents the most comprehensive research of the reproductive biology of the humpback smooth-hound shark, and is the first time the embryonic development is described for this species. These findings could contribute to the design and implementation of local management plans for this species.


2014 ◽  
Vol 65 (11) ◽  
pp. 1035 ◽  
Author(s):  
D. P. Veras ◽  
F. H. V. Hazin ◽  
I. S. L. Branco ◽  
M. T. Tolotti ◽  
G. H. Burgess

From October 2005 to March 2010, a total of 480 pelagic stingray, Pteroplatytrygon violacea, specimens, 188 females and 292 males (0.64 female : 1 male), were taken in the equatorial and south-western Atlantic by the commercial tuna longline fishery and their reproductive biology was studied. Disc widths (DW) ranged from 28.0 to 66.0 cm for females and from 34.0 to 59.6 cm for males. Size at first sexual maturity was estimated at ~48.0 cm DW (first pregnant female) for females and ~41.0 cm DW for males. Ovarian fecundity, considering only follicles larger than 0.5 cm in diameter, ranged from 1 to 17 follicles per female, while the uterine fecundity of embryos in pregnant females in Stages 2 and 3 ranged from 1 to 5 embryos per female. The sex ratio between the embryos was almost equal (1.08 female : 1 male) and the size at birth was 19.0 cm DW.



1998 ◽  
Vol 49 (7) ◽  
pp. 687 ◽  
Author(s):  
Colin A. Simpfendorfer ◽  
Philip Unsworth

The whiskery shark, Furgaleus macki, is important in the commercial shark fishery off southern Western Australia. The reproductive biology was studied with the aid of 88 specimens collected by commercial gill-net vessels off south-western Australia between March 1994 and August 1996. The size selectivity of the gill-nets resulted in only mature and large juvenile specimens being caught. Size at birth was estimated to be 22–27 cm total length. Size (fork length) at maturity was 107 cm for males and 112 cm for females. There is a seasonal reproductive cycle. Mating is most likely to occur from August to September, with females storing spermatozoa until ovulation in late January to early April. Gestation lasts 7–9 months, with parturition from August to October. Litter sizes vary from 4 to 28 (mean 19). There was a significant linear relationship between litter size and maternal length. Mature males mate each year, but females produce litters every second year. Mature non-pregnant females develop large yolky ova from March to October, with development of the ova completed several months before ovulation. The results are compared with previous records and with data for other species of the family Triakidae that occur off southern Australia.



2021 ◽  
Vol 13 (7) ◽  
pp. 3816
Author(s):  
Javier Rodrigo-Ilarri ◽  
Camilo-A. Vargas-Terranova ◽  
María-Elena Rodrigo-Clavero ◽  
Paula-A. Bustos-Castro

For the first time in the scientific literature, this research shows an analysis of the implementation of circular economy techniques under sustainable development framework in six municipalities with a depressed economy in Colombia. The analysis is based on solid waste data production at a local scale, the valuation of the waste for subsequent recycling, and the identification and quantification of the variables associated with the treatment and final disposal of waste, in accordance with the Colombian regulatory framework. Waste generation data are obtained considering three different scenarios, in which a comparison between the simulated values and those established in the management plans are compared. Important differences have been identified between the waste management programs of each municipality, specifically regarding the components of waste collection, transportation and disposal, participation of environmental reclaimers, and potential use of materials. These differences are fundamentally associated with the different administrative processes considered for each individual municipality. This research is a good starting point for the development of waste management models based on circular economy techniques, through the subsequent implementation of an office tool in depressed regions such as those studied.



Reproduction ◽  
2009 ◽  
Vol 138 (6) ◽  
pp. 979-986 ◽  
Author(s):  
Hemin Zhang ◽  
Desheng Li ◽  
Chendong Wang ◽  
Vanessa Hull

Successful conservation of an endangered species relies on a good understanding of its reproductive biology, but there are large knowledge gaps. For example, many questions remain unanswered with regard to gestation and fetal development in the giant panda. We take advantage of a sample size that is unprecedented for this species (n=13) to explore patterns in reproductive development across individuals at the China Conservation and Research Center for the Giant Panda. We use ultrasound techniques on multiple giant pandas for the first time to empirically confirm what has long been suspected that pandas exhibit delayed implantation of the embryo. We also show that the duration of postfetal detection period is remarkably similar across individuals (16.85±1.34 days). Detection of fetus by ultrasound was strongly correlated to the peak in urinary progesterone (r=0.96, t=8.48, d.f.=8, P=0.0001) and swelling in the mammary glands (r=0.79, t=3.61, d.f.=8, P=0.007) and vulva (r=0.91, t=6.40, d.f.=8, P=0.0002) of adult females. When controlling for both the duration of the total gestation period and the postfetal detection period, infant birth weight was only significantly predicted by the latter (β=11.25, s.e.m.=4.98, t=2.26, P=0.05), suggesting that delayed implantation increases flexibility in the timing of birth but is not important in dictating infant growth. This study informs reproductive biology by exploring the little-studied phenomenon of delayed implantation in relationship to physiological changes in pregnant giant panda females.



Zootaxa ◽  
2021 ◽  
Vol 4959 (1) ◽  
pp. 1-178
Author(s):  
RODRIGO M. BARAHONA-SEGOVIA ◽  
PAMELA RIERA ◽  
LAURA PAÑINAO-MONSÁLVEZ ◽  
VICENTE VALDÉS GUZMÁN ◽  
PATRICIA HENRÍQUEZ-PISKULICH

Syrphidae, more commonly known as flower flies, are considered one of the most important Diptera families worldwide because of their critical role in pollination, biological control and decomposition of organic matter. The study of these flies in Chile has stagnated due to a lack of local experts as well as the absence of an updated catalog of species. This study is an attempt to remedy the latter of these issues by providing an illustrated and updated catalog to the Syrphidae of Chile. Species are presented under currently accepted names, with synonyms and previous combinations listed and original references. Type localities, world and Chilean distribution by geopolitical Chilean regions, taxonomic and biological notes, a complete record of bibliographic references and extinction risk under IUCN Red List criteria are provided. This catalog recognizes 132 species of Syrphidae, belonging to four subfamilies (Eristalinae, Microdontinae, Pipizinae and Syrphinae), 13 tribes and 47 genera. A total of 46 species (34.84 %) is restricted to the geopolitical territory of Chile. Eight species are considered exotic, one is considered incertae sedis and three are based on doubtful records. Seventeen species of 10 different genera (Copestylum Macquart, 1846; Dolichogyna Macquart, 1842; Eosalpingogaster Hull, 1949b; Eupeodes Osten Sacken, 1877; Meromacrus Rondani, 1848; Palpada Macquart, 1834; Paragus Latreille, 1804; Sphiximorpha Rondani, 1850; Sterphus Philippi, 1865 and Toxomerus Macquart, 1855) are reported from Chile for the first time. A total of 44 species (33.33 %) reported from Chile are directly threatened by human activities such as agriculture, forestry, mining and/or urbanization and indirectly by climate change. The gaps found in the geographic distribution of Chilean flower fly species and what it means for its use by disciplines such as ecology, floral biology and agronomy, are discussed. In addition, the use of this illustrated catalog for biological conservation, the potential definition of priority areas and ecosystem management plans based on this group of Diptera are also discussed. 



2016 ◽  
Vol 16 (4) ◽  
Author(s):  
Camila S. Lima ◽  
Marta Elena Fabián

Abstract Bats of the Phyllostomidae family exhibit different reproductive patterns in Neotropical regions and the strategy adopted depends on the regional climate. Here we studied the reproductive biology of Artibeus fimbriatus at the southern limit of their distribution in Brazil. This region has no rainy season, and the climate is characterized by high temperatures and variable photoperiods. We examined 129 A. fimbriatus females over several months, and used histological procedures where necessary in order to determine whether bats were pregnant. Females exhibited a long reproductive period and were pregnant from June until February. The reproduction events were found to be dependent on the photoperiod, but independent of annual accumulated precipitation. Our results show that at the southern limit of their distribution, A. fimbriatus exhibit seasonal-dependent reproductive patterns, with parturition events occurring during spring and summer, in which the days are longer and temperature is warmer.





2007 ◽  
Vol 4 (5) ◽  
pp. 3267-3299 ◽  
Author(s):  
L. Beaufort ◽  
M. Couapel ◽  
N. Buchet ◽  
H. Claustre

Abstract. BIOSOPE cruise achieved an oceanographic transect from the Marquise Islands to the Peru-Chili upwelling (PCU) via the centre of the South Pacific Gyre (SPG). Water samples from 6 depths in the euphotic zone were collected at 20 stations. The concentrations of suspended calcite particles, coccolithophores cells and detached coccoliths were estimated together with size and weight using an automatic polarizing microscope, a digital camera, and a collection of softwares performing morphometry and pattern recognition. Some of these softwares are new and described here for the first time. The coccolithophores standing stocks are usually low and reach maxima west of the PCU. The coccoliths of Emiliania huxleyi, Gephyrocapsa spp. and Crenalithus spp. (Order Isochrysidales) represent 50% of all the suspended calcite particles detected in the size range 0.1–46 μm (21% of PIC in term of the calcite weight). The latter species are found to grow preferentially in the Chlorophyll maximum zone. In the SPG their maximum concentrations was found to occur between 150 and 200 m, which is very deep for these taxa. The weight and size of coccoliths and coccospheres are correlated. Large and heavy coccoliths and coccospheres are found in the regions with relative higher fertility in the Marquises Island and in the PCU. Small and light coccoliths and coccospheres are found west of the PCU. This distribution may correspond to that of the concentration of calcium and carbonate ions.



2010 ◽  
Vol 31 (4) ◽  
pp. 463-473 ◽  
Author(s):  
Roberta Richard Pinto ◽  
Otavio Augusto Vuolo Marques ◽  
Ronaldo Fernandes

AbstractThe reproductive biology of Chironius flavolineatus and C. quadricarinatus from the Brazilian Cerrado domain is described, including sexual maturity, female fecundity, and reproductive cycles of males and females. Egg-laying is recorded here for the first time for C. quadricarinatus. Males of both species attain sexual maturity with a smaller snout-vent length than females. Females of C. flavolineatus have an extended reproductive cycle with egg production during the wet season, whereas males exhibit year-round sperm production. Chironius quadricarinatus has continuous reproductive cycles in both sexes. Differences in reproductive pattern between these two sympatric species are probably related to phylogenetic constraints on intrageneric lineages of Chironius.



2020 ◽  
Vol 192 ◽  
pp. 105178 ◽  
Author(s):  
Inma Álvarez-Fernández ◽  
Juan Freire ◽  
Inés Naya ◽  
Nuria Fernández ◽  
Noela Sánchez-Carnero


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