#cristina rodriguez-cabello

[unofficial-sean]

In this study, the authors examined logbooks from trawl surveys, commercial vessels, and tagging surveys dating from 1983 to 2011 in the Bay of Biscay (northern Spain and western France) for catch records of Hexanchus griseus. This bay is defined by an extensive continental shelf along western France, and a much steeper, narrower shelf around Spain.

In this image, we can see locations of the catches. Red dots are from trawl surveys and the yellow rhombus’ are from electronic logbooks of longline vessels.

The purpose of this study was to examine all existing data of H. griseus in this area to better understand the shark’s ecology, distribution, seasonality, and swimming behavior.

According to the e-logs, most of the sharks caught were from NW Spain during autumn and winter months. Catch depth ranged from 100m to 1750m and weight of captured specimens was estimated to be between 50kg to 600kg. This weight data can be turned into a TL estimate through a developed formula (W = a*TL^b), and the range was 2 meters to 4.5 meters total length.

When examining the trawling surveys, however, most of the individuals were 60cm to 121cm TL; neonates and juveniles. This fascinating dichotomy has a couple explanations. It could mean that H. griseus is spatially segregated by age, with younger sharks occupying shallower waters and older sharks occupying deeper waters. Another explanation could be that larger sharks are better able to escape a trawl net than smaller sharks. This bias could not be ruled out. Larger sharks are faster and better able to evade threats than their smaller relatives.

Most of the large sharks were caught by longline and gillnet vessels, with the gear hovering about 2.5m-10m above the sea floor. All this bearing in mind, it aligns with many other similar studies of H. griseus. This shark occupies and epibenthic space where smaller specimens stay in shallower waters and larger sharks occupy deeper waters. No sex relationship could be discerned, as much of that data was not recorded. But based on other studies, we also know that H. griseus tends to segregate by sex, as well, post-maturation.

Above is a map showing the locations of two tagged sharks caught via longline tagging survey. Shark 1 was equipped with a rototag and was recovered 3 years after tagging by a gillnet vessel 9nm away, outside the Marine Protected Area (MPA). The shark was released after catch, but no morphometric data was recorded beforehand, sadly.

Shark 2′s story is far more interesting, and will take up the bulk of this discussion. Shark 2 was equipped with an MPAT tag--a satellite tag that records depth and temperature over time before releasing itself and floating to the surface for recovery and dissemination--and the data recorded gives us a lot to work with. The tag itself was released prematurely after just 84 days. This was due to a contingency designed in the event that depth measurements do not significantly change after a nine day period. Thus, 75 days of valid data were recorded.

The tag released only 4nm (nautical miles) from the equipment location. the last 7 days of the tags data showed a constant depth, suggesting that the shark died and was resting on the sea floor. Some oscillating depth variation was displayed, but that was due to the tides. You may be wondering what killed Shark 2, and the answer is unclear. The authors speculate that physiological trauma from the catch was responsible; citing gas bubble formations in the tissues. This is not an unreasonable inference. Hexanchus griseus has, historically, displayed a recovery period after catch lasting up to 72 hours, wherein erratic behavior is suggested by depth over time recordings.

It is possible that Shark 2 suffered for much longer, however. We do see this erratic behavior in the graph, below, but other natural causes are also possible. Parasites, disease, and predation could also be to blame, other than fatigue.

Figure A shows the recovery period, and Figure B shows the moment of death. Examining the whole, though, we can see that Shark 2 returned to a depth of 900m-1000m after stabilizing. The oscillations could be from the shark getting pushed around by tidal currents, or it could be an active swimming pattern or foraging up and down the slopes.

This data provides an interesting contrast to studies performed on H. griseus around Hawaii and Virginia, where the sharks occupied shallower waters (200m-450m) and displayed more movement. That’s more than double the daily depth variation on display with Shark 2 (note: for the uninitiated, H. griseus occupies shallower waters at night, then makes a vertical migration at dawn to deeper waters for the day, and at dusk returns to shallow waters). Those waters are poorer, however, which would necessitate greater foraging effort. The Cantabrian Sea is a biologically rich area of the ocean, so H. griseus’ ranging in the Bay of Biscay likely do not require such activity for sustenance.

Despite all this, this is a case study of a presumed dead shark. We cannot assert any pattern of behavior from it.

While H. griseus is found most commonly along continental slopes, they have been seen around islands and sea mounts, such as the juvenile spotted SE of Rapa Nui a few years ago, suggesting that this species is capable of long-range migration. Younger individuals, however, tend to remain in a relatively small area, as is the case in Puget Sound, a highly productive estuary and nursery for this species. Young H. griseus spends around four years developing in the Sound before leaving for the open ocean. It is likely that the sharks living in the Cantabrian sea do not migrate very far, as inferred by Sharks 1 and 2 being tagged and recovered in and around the MPA.

An interesting anomaly I learned while reading is that H. griseus can survive in temperatures as high at 20 degrees Celsius, but appear to prefer 8-13 degrees.

One of the things I drew from this study is how our actions affect the life we study. By dragging Shark 2 up from 1km beneath the surface to tag it, the researchers may very well have been responsible for its death. With the current state of ROV technology, perhaps we can avoid these fatalities and disruptions by tagging and observing Hexanchus griseus remotely, without hoisting them from the sea. We must account for the effect of our physical interactions with the subject and its effects on the data and observations we record.

No doubt the researchers didn’t know the shark would die. It’s possible that the shark was already in poor health and susceptible to extreme consequences of catch-and-release methods. After all, other Hexanchus griseus subjects have underwent the same treatment and lived. But this isn’t about numbers--if I may take an emotional stance for a moment--it’s about expanding our knowledge without destroying those which we seek to understand; and I think we’re finally able to achieve that.

Until next time.

[whoisjazzzmin]

who am i? / quien soy?

español - (english version bellow)

hola! me llamo jazmin, tengo 21 años y soy de buenos aires, argentina. estudio diseño grafico y me gusta mucho la fotografia. me encanta ver series y peliculas y POR SOBRE TODO opinar, en exceso diria yo.

es raro tener que explicar esto pero este es un lugar seguro para todas las personas que me hablen con respeto. no importa su genero, sexualidad, nacionalidad, etc.

my box/dms estan abiertos siempre para quien lo necesite y sino la opcion de preguntas tiene el anonimo activado.

para que me conozcan un poco mas:

mis bandas favoritas 5sos, 1d, the vamps, all time low, los rodriguez, la vela puerca, simple plan, anarbor, mayday parade.

cantantes bea miller, maggie lindemann, louis tomlinson, harry styles, madison beer, camila cabello, luke hemmings, ashton irwin, shawn mendes, niall horan, ed sheeran, olivia o'brien, leyla blue.

series bojack horseman !!, skam (noruega), rupaul's drag race + all stars, the wilds, skins, girl boss, pll, revenge, black mirror, the haunting of..., dexter (temporada 6), grey's anatomy (temporada 11), bates motel.

peliculas harry potter, it, the truman show, room, split, enredados, robin hood (verison vieja de disney), los aristogatos, narnia, maze runner.

libros red, white & royal blue, saga de los habitantes del aire, starters, harry potter, it, carrie, la leccion de august, el angel de cristina (infantil).

gracias por leer xx

english -

hi! i'm jazmin (pronunced like has mean, kinda), i'm 21 and from buenos aires, argentina. i'm a graphic design student and i love photography. i love series and movies and ABOVE ALL i love to give my view in anything, maybe too much.

is weird to have explicitly say this but this IS A SAFE PLACE for everyone. gender, sexuality, nationality; it doesn’t matter.

my box/dms are always open for everyone that needs them, at any time or, if you prefer, the questions are anonymous.

now, if you wanna know me a little bit better (anything that's spanish will be orange):

my favorite bands 5sos, 1d, the vamps, all time low, los rodriguez, la vela puerca, simple plan, anarbor, mayday parade.

singers bea miller, maggie lindemann, louis tomlinson, harry styles, madison beer, camila cabello, luke hemmings, ashton irwin, shawn mendes, niall horan, ed sheeran, olivia o'brien, leyla blue.

series bojack horseman !!, skam (norway), rupaul's drag race + all stars, the wilds, skins, girl boss, pll, revenge, black mirror, the haunting of..., dexter (season 6), grey's anatomy (s11), bates motel.

movies harry potter, it, the truman show, room, split, tangled, robin hood (old disney), aristocats, narnia, maze runner.

books red, white & royal blue, the folk of the air saga, starters, harry potter, it, carrie, wonder, el angel de cristina.

thank u for reading xx

[lanetasiempre]

Seguramente formas parte de ese nutrido grupo de personas que piensan que todas las fashion blogger son mujeres de grandes tacones y súper estiradas tipo Miranda Priestly en la famosa película “El Diablo viste a la moda”, pero eso es algo alejado totalmente de la realidad y un ejemplo de ello es Vanessa Zambito.

Esta joven nacida en Maracay (Venezuela) hace 22 años, se ha dado a conocer en el mundo de las redes sociales con un estilo sumamente sencillo el cual le ha servido de trampolín para triunfar en Estados Unidos.

La fashion blogger de los zapatos de goma y los tacones también

Vanessa es sumamente popular en sus redes sociales por la juventud y carisma que irradia. De acuerdo a una entrevista concedida al diario Notitarde, ella misma se autodefine como “La fashion blogger de los zapatos de goma y los tacones también”.

(Lee también: Cristina Maag, una blogger que representa a la nueva generación de Influencers  l)

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(Lee también: Ilse Rodriguez, vs Mariana Salinas, bloggers de moda y belleza que apuntan alto)

De pequeña su sueño era estudiar moda, pero al no tener el apoyo suficiente tomó la decisión de abrir un blog, ya que con él podía matar 2 pájaros con un solo tiro, es decir podía aprender y a la vez enseñar sobre el mundo fashion.

Fue de esta manera que Zambito se convirtió en la blogger de moda y estilo de vida que poco a poco ha ido calando posición en esta difícil industria.

Su camino hacia el sueño americano

Poseedora de la cuenta Instagram vanessazambito con más de 110 mil followers, como toda joven que va a Estados Unidos tras un sueño, Vanesa tuvo que trabajando en tiendas vendiendo cosméticos para el cabello, artículos de uso personal y hasta desengrasantes de ollas.

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Si quieres formar parte de nuestra lista de influencers haz clic aquí

Al final todo valió la pena, en la actualidad es dueña de una marca de ropa con su nombre, además de ser hacedora de armarios. Esta última labor inició renovando los atuendos de nada más y nada menos que de Inger Mendoza o mejor dicho la ex esposa de Nacho.

Una cosa que llama la atención sobre esta joven es que parte de su trabajo tiene un sentido social, por ejemplo, en el 2019 hizo tres ventas de productos de belleza y prendas de vestir, todo el dinero recaudado fue destinado a ayuda humanitaria y otra parte a la institución OdontoÁngel ubicado en el estado Aragua.

Los deportivos, su gran pasión

Vanessa es una gran aficionada a los zapatos deportivos, es de las que opina que lucen con todo, con faldas, pantalones, vestidos, shorts y bragas.

Si eres empresa y quieres trabajar con nosotros haz clic aquí

La mayoría de sus looks son con estas zapatillas, la hacen sentir súper bien, claro nunca faltan en su closet las sandalias altas y unos tacones nude que la hagan lucir más bella de lo que ya es.

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via La Neta – La comunidad más grande de influencers emergentes y creadores en español