scholarly journals A novel system for intensive Diadema antillarum propagation as a step towards population enhancement

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aaron R. Pilnick ◽  
Keri L. O’Neil ◽  
Martin Moe ◽  
Joshua T. Patterson
Keyword(s):  
Ex Situ ◽  
Diadema Antillarum ◽  
Lunar Periodicity ◽  
Recirculating Aquaculture ◽  
In Captivity ◽  
Broodstock Management ◽  
Culture Process ◽  
Ecological Shifts ◽  
The Caribbean ◽  
Very High

AbstractThe long-spined sea urchin Diadema antillarum was once an abundant reef grazing herbivore throughout the Caribbean. During the early 1980s, D. antillarum populations were reduced by > 93% due to an undescribed disease. This event resulted in a lack of functional reef herbivory and contributed to ongoing ecological shifts from hard coral towards macroalgae dominated reefs. Limited natural recovery has increased interest in a range of strategies for augmenting herbivory. An area of focus has been developing scalable ex situ methods for rearing D. antillarum from gametes. The ultimate use of such a tool would be exploring hatchery origin restocking strategies. Intensive ex situ aquaculture is a potentially viable, yet difficult, method for producing D. antillarum at scales necessary to facilitate restocking. Here we describe a purpose-built, novel recirculating aquaculture system and the broodstock management and larval culture process that has produced multiple D. antillarum cohorts, and which has the potential for practical application in a dedicated hatchery setting. Adult animals held in captivity can be induced to spawn year-round, with some evidence for annual and lunar periodicity. Fecundity and fertilization rates are both consistently very high, yet challenges persist in both late stage larval development and early post-settlement survival. Initial success was realized with production of 100 juvenile D. antillarum from ~ 1200 competent larvae. While the system we describe requires a significant level of investment and technical expertise, this work advances D. antillarum culture efforts in potential future hatchery settings and improves the viability of scalable ex situ production for population enhancement.

scholarly journals Individualization and Electrical Characterization of SiGe Nanowires

2012 ◽  
Vol 1408 ◽  
Author(s):  
M. Monasterio ◽  
A. Rodríguez ◽  
T. Rodríguez ◽  
C. Ballesteros
Keyword(s):  
Electrical Characterization ◽  
Ex Situ ◽  
Electrical Measurements ◽  
Measured Resistance ◽  
Single Nanowires ◽  
Very High

ABSTRACTSiGe nanowires of different Ge atomic fractions up to 15% were grown and ex-situ n-type doped by diffusion from a solid source in contact with the sample. The phenomenon of dielectrophoresis was used to locate single nanowires between pairs of electrodes in order to carry out electrical measurements. The measured resistance of the as-grown nanowires is very high, but it decreases more than three orders of magnitude upon doping, indicating that the doping procedure used has been effective.

scholarly journals Occurrence of Toxoplasma gondii antibodies in lowland tapirs maintained ex situ in Brazil and Paraguay

2017 ◽  
Vol 47 (3) ◽  
Author(s):  
Maria Fernanda Naegeli Gondim ◽  
◽  
Igor da Cunha Lima Acosta ◽  
Maria Cristina Valdetaro Rangel ◽  
Herbert Sousa Soares ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Clinical Signs ◽  
Ex Situ ◽  
Serum Samples ◽  
High Exposure ◽  
Modified Agglutination Test ◽  
In Captivity ◽  
Tapirus Terrestris ◽  
And Gender ◽  
Land Mammal

ABSTRACT: Lowland Tapir ( Tapirus terrestris ) is the second largest South American land mammal. It is strictly herbivorous and its exposure to Toxoplasma gondii should be indicative of environmental contamination by oocysts.In the present study antibodies to T. gondii in 47 Brazilian tapirs maintained ex situ in 10 Brazilian and in one Paraguayan institution were sought in serum samples by the modified agglutination test (MAT ≥25). None of the animals presented clinical signs during the study. From 47 animals 35 (74.5%) were positive with titers of 25 in 8, 50 in 6, 100 in 12, 200 in 5, 400 in 1 and 800 in 3. One animal had samples collected on twice, and 19 were born in captivity. There was no association between occurrence of T. gondii antibodies and gender, and positive animals were reported in all institutions. The high occurrence of seropositive tapirs born ininstitutions (54.3%) confirmed the high exposure of these mammals to T. gondii in captivity. Only two cases ofabortion were reported, but it was not possible to correlate these abortions to T. gondii infection.

scholarly journals The Peculiarities and Farming Challenges of Atlantic Bluefin Tuna (Thunnus thynnus, L. 1758)

2020 ◽  
Vol 78 (1) ◽  
pp. 33-44
Author(s):  
Gorana Jelić Mrčelić ◽  
Ivana Miletić ◽  
Marina Piria ◽  
Ambroz Grgičević ◽  
Merica Slišković
Keyword(s):  
Stock Assessment ◽  
Market Price ◽  
Bluefin Tuna ◽  
Breeding Cycle ◽  
Farmed Fish ◽  
Atlantic Bluefin Tuna ◽  
Intensive Farming ◽  
In Captivity ◽  
High Degree ◽  
Very High

AbstractThe aim of this paper is to provide an overview of bluefin tuna, with special regard to its farming challenges. Tuna is one of the most prominent species in fisheries worldwide. The high market value of tuna stocks has led to intensified fishing pressure that resulted in drastic population reductions in every ocean where these fish are found. It is very difficult to obtain the necessary data for the appropriate stock assessment analysis, and there is a very high degree of uncertainty in the models used to evaluate Atlantic bluefin tuna stocks. Tuna-farming could help reduce pressure on the tuna population, but the problem is that the majority of cage-farmed fish is caught in its natural environment (wild population), and thus is fattened or farmed to a certain size. Additionally, the challenges in tuna farming are numerous. Tuna is a fast swimmer, a large energy and oxygen consumer, therefore consuming a large portion of available food to maintain its metabolism. However, due to its delicious taste, high market price and a large demand for this species, pressure will probably continue to grow in the future. Therefore intensive farming, which implies the full breeding cycle in captivity, remains one of the possible solutions that could help reduce the pressure on the tuna population.

scholarly journals Broodstock management of the fine flounder Paralichthys adspersus (Steindachner, 1867) using recirculating aquaculture systems

2013 ◽  
Vol 41 (1) ◽  
pp. 89-98 ◽  
Author(s):  
Lili Carrera ◽  
Noemi Cota ◽  
Melissa Montes ◽  
Enrique Mateo ◽  
Veronica Sierralta ◽  
...  
Keyword(s):  
Recirculating Aquaculture ◽  
Recirculating Aquaculture Systems ◽  
Broodstock Management

scholarly journals EVALUACIÓN DE AMENAZAS ANTROPOGÉNICAS EN ECOSISTEMAS DE PLAYA EN SAN ANDRÉS, UNA ISLA PEQUEÑA DEL CARIBE SUROCCIDENTAL

2016 ◽  
Vol 44 (1) ◽  
Author(s):  
Luis A. Guerra Vargas ◽  
José Ernesto Mancera Pineda
Keyword(s):  
Urban Development ◽  
Land Reclamation ◽  
Pressure Level ◽  
Oceanic Island ◽  
Social Cartography ◽  
Management Plans ◽  
The Caribbean ◽  
San Andres ◽  
Very High ◽  
Beach Use

In this paper we present the assessment of the main threats to beach ecosystems arising from their use in San Andrés, a small oceanic island in the Caribbean. To determine each threat and its pressure level on the ecosystem, we applied surveys and, based on social cartography methods, we obtained perception maps with relative threat magnitudes for each use, from very low to very high. The results suggest that the current economic model of San Andrés, almost totally dependent on massive tourism, may increase pressure intensities to the beach ecosystems due to increased pollution, urban development, land reclamation and exploitation of coastal resources. Tourists, the motor and benefiiaries of this socio-ecosystem, may be affected by these tensors, discouraging them to visit again the island. It is recommended to include in the island´s management plans new legislations to minimize the impacts of beach use on this ecosystem.

scholarly journals Development of Sperm Cryopreservation Protocols for Sharks and Rays: New Tools for Elasmobranch Conservation

2021 ◽  
Vol 8 ◽  
Author(s):  
Pablo García-Salinas ◽  
Victor Gallego ◽  
Juan F. Asturiano
Keyword(s):  
Sperm Quality ◽  
Membrane Integrity ◽  
Egg Yolk ◽  
Ex Situ ◽  
Conservation Strategies ◽  
Sperm Cryopreservation ◽  
In Captivity ◽  
Reproductive Techniques ◽  
Elasmobranch Species ◽  
Reproductive Cycles

Elasmobranchs are one of the most endangered vertebrate groups on the planet, but despite this situation the use of reproductive techniques in elasmobranch conservation strategies has been scarce. Among these techniques, sperm preservation is a potential tool for ex situ conservation and aquaria sustainability. However, there are no widespread preservation protocols for elasmobranch sperm, and shark sperm cryopreservation has never been achieved before. Here we present the establishment of successful cryopreservation protocols for elasmobranch sperm, tested in several species. We have formulated a sperm extender that can be used for different elasmobranch species, capable of maintaining sperm motility for several weeks. Additionally, we achieved the cryopreservation of sperm by previously diluting it in our extender and supplementing it with different combinations of cryoprotectants. The effects of methanol and dimethyl sulfoxide as permeating cryoprotectants were evaluated, as well egg yolk as a non-permeating cryoprotectant. Sperm quality was assessed by studying the motility and membrane integrity post-thawing, demonstrating its effectiveness in the 10 species tested, including two which are considered Critically Endangered. This is the first time that shark sperm cryopreservation has been reported, broadening our knowledge of the reproductive techniques that can be applied to elasmobranchs and laying the foundations for the first cryobanks for shark and ray sperm. Outcomes from this study will be useful for ex situ conservation efforts developed by public aquaria. A regular supply of frozen sperm will reduce the problems that result from the transport of specimens, inbreeding or lack of synchronized reproductive cycles in captivity.

scholarly journals Spatial variation in allometric growth of invasive lionfish has management implications

2018 ◽  
Author(s):  
Juan Carlos Villaseñor-Derbez ◽  
Sean Fitzgerald
Keyword(s):  
Spatial Variation ◽  
Regional Differences ◽  
Growth Parameters ◽  
Ex Situ ◽  
Total Biomass ◽  
Allometric Growth ◽  
Management Implications ◽  
Western Atlantic ◽  
Invasive Lionfish ◽  
The Caribbean

Lionfish (Pterois volitans / miles) are an invasive species in the Western Atlantic and the Caribbean. Improving management of invasive lionfish populations requires accurate total biomass estimates, which depend on accurate estimates of allometric growth. Sedentary species like lionfish often exhibit high levels of spatial variation in life history characteristics. We review 17 published length-weight relationships for lionfish taken throughout their invasive range and found substantial regional differences in allometric growth parameters. The spatial pattern we observed is consistent with findings from other studies focusing on genetics or age-at-length. We show that the use of ex situ parameters can result in up to a threefold under- or overestimation of total weight, but using parameters from nearby regions reduces this error. These findings can have major implications for management in terms of predicting effects on local ecosystems, evaluating the effectiveness of removal programs, or estimating biomass available for harvest.

scholarly journals Exploration and Inventory of Native Orchid Germplasm in West Borneo, Indonesia

HortScience ◽  
2008 ◽  
Vol 43 (2) ◽  
pp. 554-557 ◽  
Author(s):  
Chairani Siregar
Keyword(s):  
Economic Value ◽  
Ex Situ ◽  
Forest Damage ◽  
Illegal Logging ◽  
Rain Forests ◽  
Visual Examination ◽  
Orchid Species ◽  
The Third ◽  
The World ◽  
Very High

Borneo (Kalimantan) is the third largest island in the world. It is rich with various indigenous orchid species that grow epiphytically, terrestrially, or saprophytically in the forests. Its rain forests are also home to some rare species such as some Aërides sp., Bulbophyllum sp., Cymbidium sp., Dendrobium sp., Dimorphorchis sp., Grammatophyllum sp., Paphiopedilum sp., Phalaenopsis sp., Paraphalaenopsis sp., and Vanda sp., all of which have a very high economic value. These species are endangered and some of them may have not yet been found or discovered, because of the loss of habitat resulting from fire, forest damage, illegal logging, and orchid hunting either by domestic or foreign collectors. Until recently, there are only a few records on the orchid native to West Borneo. For this reason, a research was conducted to identify and create an inventory of all orchid species that exist in West Borneo before they become extinct along with their habitat and to conserve them ex situ. This research was conducted in 10 counties and one municipal city in West Borneo, and inventory was done through exploration. Orchids found were recorded and identified into their genera and their species by visual examination of vegetative and floral characteristics, respectively. A total of 197 species of orchids from 66 genera were identified, and among those, 27 species live as terrestrials, 169 species live as epiphytes, and one species lives as both an epiphyte and terrestrial.

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