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transportemx · 5 days ago

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La Asociación Nacional de Productores de Autobuses, Camiones y Tractocamiones (ANPACT) dio a conocer cifras de la industria donde se destaca que la importación de camiones usados en la frontera norte ha crecido mientas que la producción y exportación de camiones tiene una caida respecto ames de octubre del 2023. Al destacar que la demanda sostenida de vehículos pesados en México y la expectativa de nearshoring continúan como factores que están impulsando a la cadena de valor, aparejado de la permanente innovación e inversión de la industria, la Asociación Nacional de Productores de Autobuses, Camiones y Tractocamiones (ANPACT), que preside Rogelio Arzate, informó que las ventas al mayoreo se encaminan a culminar 2024 con cifras históricas. “En el décimo mes del año continúa la expansión de las ventas de vehículos pesados con crecimiento de un 43.5% vs. lo observado en el mismo mes de 2023, tan es así que prevemos que al término del año la venta al mayoreo potencialmente llegará a alrededor de las 60 mil unidades, alza12.4% por encima de lo conseguido en el histórico año 2023, en el que rompimos récords de ventas totalizando 55,346 vehículos”, indicó Virginia Olalde López-Gavito, directora de Comercio Exterior y Estudios Económicos de la ANPACT. Al referirse al mismo indicador, pero en su acumulado de enero a octubre, Virginia Olalde puntualizó que el aumento fue de 15.1% en la comparación interanual, ya que se lograron 51,828 unidades vendidas; a esto se suma que la venta de tractocamiones al mayoreo ya superó su récord al colocarse 24.3% por encima de 2023, con 25 mil 024 unidades. Respecto a la Estrategia Nacional del Sector Eléctrico, recientemente anunciada por el gobierno de la presidenta Claudia Sheinbaum, Alejandro Osorio Carranza, director de Asuntos Públicos y Comunicación de ANPACT, consideró que ésta “podría representar una nueva oportunidad para impulsar el crecimiento del país, particularmente, sí se impulsa la generación, transmisión y distribución de energía eléctrica suficiente, limpia y competitiva, y se alienta la participación del sector privado con reglas claras que alienten la inversión, la innovación y la expansión de la red”. “Hoy más que nunca, el país necesita energía eléctrica e infraestructura energética suficiente por lo que es indispensable construir la hoja de ruta con la participación de la industria en el contexto del nearshoring y ante el avance de la electromovilidad”, añadió Osorio Carranza. La industria automotriz de vehículos pesados está comprometida con México, con el medio ambiente y con la descarbonización, por eso invierte y desarrolla nuevas tecnologías más limpias y eficientes como son lo son los vehículos eléctricos, a gas natural y, por supuesto, los vehículos con tecnología de motores Euro VI que ya están disponibles en el mercado, y que a partir del 2025 serán el modelo a producir, importar y comercializar y los cuales representan un avance importante con el medio ambiente, al generar 92% menos de Óxidos de nitrógeno (NOx’s), y 90% menos de material particulado si lo comparamos con la tecnología promedio en circulación. Virginia Olalde añadió que, con la transformación hacia nuevas tecnologías y fuentes de energía más limpias, también se fomentará el impuso a la producción. En el corte mensual de producción de vehículos pesados se registraron bajas de 7.8% con 17,302 unidades, mismo caso del periodo enero-octubre, periodo en el que se manufacturaron 179,398 vehículos pesados, lo que se tradujo en descensos de 4.0%. Respecto a la exportación de unidades pesadas, Olalde informó que llegó a 11,677 unidades en los 31 días de octubre y a 135,534 en el acumulado a diez meses, es decir, se reportaron declives de 19.3% y 9.1% en cada caso. “Toda vez que Estados Unidos se coloca como el principal destinado de las exportaciones de la industria automotriz de vehículos pesados establecida en México, estimamos que al ya definirse las elecciones presidenciales en ese país, se reactivará paulatinamente el dinamismo de dicho mercado, por lo que nos mantenemos con una expectativa positiva, siguiendo de forma permanente las políticas que instrumentará el presidente electo Donald Trump, por lo que mantendrá una estrecha coordinación con las autoridades mexicanas, por ejemplo, con la Secretaría de Economía que lidera Marcelo Ebrard, y la Secretaría de Relaciones Exteriores con el canciller Juan Ramón de la Fuente al frente, con la meta de impulsar las condiciones de certeza jurídica que requiere la industria. La reactivación de la producción también se vislumbra mediante el fortalecimiento del mercado interno, con el impulso de nuevos mecanismos de financiamiento, programas de chatarrización, así como de inversión en infraestructura carretera y energética”, comentó Alejandro Osorio. En dicha ruta, ANPACT refrendó el compromiso del sector para abonar a una movilidad cada vez más sostenible en términos de eficiencia y seguridad, pero también al poner al centro de las estrategias a las personas, tanto usuarias como parte de la cadena de valor, así como la reducción de emisiones, indispensable para el resguardo de la salud pública y los ecosistemas. Para finalizar, Alejandro Osorio informó que ANPACT y sus asociados están teniendo diversas reuniones de trabajo con representantes de los Poderes Legislativo y Ejecutivo, para plantear la agenda estratégica de la industria, que subraya la importancia de la renovación de la flota, el desarrollo de la infraestructura energética, la implementación de instrumentos financieros, así como consolidar el liderazgo mundial de la industria, con mecanismos que brindan certeza y claridad comercial como el T-MEC. Read the full article

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acapulcopress · 4 months ago

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Largo camino para el desarrollo integral de Guerrero

Maremágnum » RICARDO | CASTILLO BARRIENTOS ) Acapulco Press La mayoría de los guerrerenses tienen conocimiento del gran potencial económico de su entidad federativa, no solo en el sector turístico, sino en otros sectores como agropecuario, minero, pesquero, industrial, construcción, comercio, artesanal y servicios. Estos componentes económicos, tienen un incipiente desarrollo por causas diversas, los más significativos, limitados apoyos institucionales, abandono del campo, la migración y falta de nuevas herramientas tecnológicas agrícolas. El estado de Guerrero está ubicado en los últimos lugares del desarrollo nacional con Oaxaca y Chiapas, sin que logren remontar sus posiciones históricas, generándose fuerte desequilibrio económico con otras entidades federativas, de notables niveles de desarrollo en distintos sectores de la economía y en el aspecto social. Pese a las adversidades económicas y sociales, Guerrero, principal productor de mango y copra, segundo en ajonjolí y tercero en melón y cacao. Destaca la producción de café, plátano, papaya, limón, jamaica, agave, nopal, aguacate, vainilla y cempasúchil, productos del campo considerados en el Censo Agropecuario de 2022. Estos productos agrícolas tienen mercado nacional e internacional en menor escala; los artículos de joyería de plata son de excelente aceptación en el extranjero, con un monto de 4.5 millones de dólares. Taxco tiene una clientela cautiva en sus asiduos visitantes. La minería es pródiga en extracciones de productos minerales: oro, plata, cobre, plomo, hierro, zinc, mercurio, antimonio y tungsteno, en su mayor parte, son explotados por compañías canadienses, la Torex Gold y Equinox Gold, en la zona Norte. El Gobierno del Estado, a través de la Secretaría de Fomento y Desarrollo Económico, a cargo de Teodora Ramírez Vega, está promoviendo el programa de capacitación y asistencia técnica de NAFIN, los programas y productos de FIRA, para la reactivación económica de Acapulco, por parte del Centro de Competitividad México (CCMX). Por indicaciones de la gobernadora Evelyn Salgado Pineda, se están realizando negociaciones con el Grupo Syan, empresa especializada en la colocación de productos frescos en el mercado canadiense, a fin de enviar remesas de cocos frescos de la Costa Chica y Costa Grande. Primer producto hacia Canadá e irán incrementándose otros productos de las regiones de la entidad. Guerrero tiene una vocación profundamente artesanal, debido a la existencia de cinco grupos étnicos, en las regiones de La Montaña, Costa Chica y Centro, donde se elaboran una gran variedad de artesanías, desafortunadamente, no han tenido el apoyo institucional. El Fideicomiso de la Palma (FIDEPAL), fue extinguido por gobiernos neoliberales, cuando representaba importante fuente de empleo para los indígenas de la Montaña Baja, con sede en Chilapa, siendo productos de alta calidad y muy solicitados, como el mezcal artesanal. Las posibilidades de desarrollo integral, ha sido bastante incierta y tardía en las últimas décadas, pues no fue prioridad para los gobernantes en turno, dando paliativos, sin compenetrarse a fondo en la aguda problemática, preocupante para los guerrerenses. Podrían venir mejores tiempos para la economía local, una vez que asuma la presidencia de la República, la doctora Claudia Sheinbaum y sí aprueba la instalación de dos o tres parques industriales de nearshoring (cadena de suministro) y de industrialización agrícola, de los 100 que se propone construir en el país. Esta alternativa económica podría consolidarse por las magníficas relaciones de la gobernadora Salgado Pineda con la próxima presidenta de México, en compensación al apoyo político que le brindó en su campaña presidencial y la identificación con ella. Marea Baja.- El gobierno estatal puso en marcha “Programa de Modernización de Áreas Verdes”, en la ciudad de Chilpancingo, con la finalidad de dotar a la capital del estado de una mejor imagen urbana, basada en un mayor cuidado del medio ambiente con el rescate y mejora de los espacios verdes. La primera etapa inició en la avenida Ruffo Figueroa y la colonia Haciendita. Los trabajos incluyen limpieza, retiro y contención de la maleza en camellones centrales y la poda de 56 palmeras; se sembrarán arbustos, plantas y pasto; así como la sustitución de 96 luminarias y el pintado de 48 postes, con ello se contribuirá a la dignificación de la imagen urbana de la menguada capital. Marea Alta.- La impunidad no se logró imponer al aplicarse una sentencia de 140 años por homicidio calificado, al sicario de la Familia Michoacana, Hermelindo “N”, alias “El Meli” o “El Chiquillo”, por su responsabilidad en la muerte de siete personas, en el Ejido El Durazno, municipio de Coyuca de Catalán, en la Tierra Caliente. La masacre se registró el 10 de diciembre de 2022, con la participación de varios sicarios que llegaron a bordo de camionetas, Hermelindo es el primero en aplicarse todo el rigor de la ley. Maremoto.- La voracidad en la política no tiene límites con el destape prematuro de la alcaldesa Abelina López Rodríguez, todavía no toma posesión del segundo periodo, y ya se ha lanzado descaradamente en pos de la gubernatura por Morena. Su ambición política repercutirá en la administración municipal, porque la política partidista será la principal actividad a desarrollar, en grave detrimento de las funciones sustantiva de la comuna local. Abelina tiene cifradas esperanzas en Marcelo Ebrard, próximo secretario de Economía federal, quien ya le cumplió con la reelección y naturalmente, la nueva mandataria nacional, Claudia Sheinbaqum le retiraría el apoyo. “El Señor de las Ligas”, René Bejarano, hizo su aparición al lado de Abelina, sin escrúpulos hace alianzas hasta con el chamuco. No pasemos por alto que le están moviendo el tapete con la recolección de firmas para su desafuero, por el fracaso de su gobierno al frente del municipio más importante de Guerrero. www.acapulcopress.com Read the full article

#AbelinaLópezRodríguez #ClaudiaSheinbaum #EvelynSalgadoPineda #LaFamiliaMichoacana #Maremágnum #RicardoCastilloBarrientos

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montereybayaquarium · 6 years ago

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New insights to help young white sharks survive

What can scientists studying white sharks learn from an expert on mountain lions? As it turns out, quite a lot.

Such a collaboration is on display in new research published in the Journal of Applied Ecology. Models that estimate survival rates for top predators on land, according to the study, can also work in the ocean. The research also revealed important safeguards that can help protect white sharks while they’re young and vulnerable.

At the heart of the effort was the work of lead author John Benson. Before taking his current role as a professor at the University of Nebraska, John was a post-doctoral researcher at the Monterey Bay Aquarium, working with senior research scientist Sal Jorgensen.

John’s past work also involved black bears in Louisiana, panthers in Florida, wolves and coyotes in Canada, and moose and their various predators in Alaska. After so much experience on land, John saw working with Sal at the aquarium as a chance to—as the saying goes—get his feet wet.

Estimating sharks’ survival rates

John realized there was an opportunity for a new approach for estimating juvenile shark survival, tapping data from electronic tags placed on the sharks to develop what are called “known-fate models.”

“They’re a very direct way of estimating survival and mortality,” he says.

The technique hinges on determining what happens to individuals—information that has been elusive historically, because of the difficulty of tracking animals in the ocean.

“It’s generally much easier to study animals on land,” John notes. “The animal tracking technology that helped us learn so many new things about terrestrial species decades ago, with radio telemetry and collars, has only recently become available in the marine environment.”

Researchers from the aquarium, California State University, Long Beach, and Mexico’s Ensenada Center for Scientific Research and Higher Education have been tagging and tracking juvenile white sharks with various devices since 2000. Sal and his colleagues have deployed devices called PATs, or pop-up archival tags, on both adult and juvenile white sharks.

A recovered white shark satellite tag, full of data!

Untapped information

These tagged sharks had already taught us a lot about their travels, but the tags contained additional untapped information. Specifically, they let researchers to know each shark’s exact fate—whether it lives, died naturally, or ended up caught in fishing gear. John was able to use the data to develop a survival estimate for the population of juvenile sharks in Southern California and Baja California.

Over the course of 16 years, the team of scientists in California and Mexico tracked 37 young white sharks. From the known fate of all these tagged animals, John estimated that 63 percent of juveniles survive each year.

The paper showcases a powerful statistical tool, Sal says—one that’s useful not just for sharks. Thousands of pop-up tags have been deployed on marine species worldwide, but until now, nobody had used their data in this way.

“We were surprised to see that we were the first to apply this methodology on PAT tags,” he says. “This will pave the way for researchers to estimate annual survival, so vital to conservation for many other ocean species.”

Young sharks and gillnets

Of the 37 young white sharks studied, one was eaten, though by which predator is unclear. Six died after run-ins with fishing gear, most often gillnets—a kind of mesh curtain designed to trap halibut and other bottom-dwelling fish in nearshore waters.

“We were able to see when sharks interacted with gillnets, when they were entangled but released, and when they were killed,” Sal says.

From these data, a few patterns emerged. One is that the bigger a shark grows, the less danger a gillnet poses—possibly because larger sharks snagged in gillnets are better able to fight their way free. The paper also found that more young white sharks died off the coast of Baja, compared with Southern California.

Thank you to @noaasanctuaries for the graphic!

That might stem partly from differences in the way fisheries are managed. White sharks are a protected species in both countries, and it is illegal to catch or sell white sharks. However, other related regulations differ between the U.S. and Mexico. In the U.S., gillnets are banned within three miles of the California coast; Mexico has instituted a three-month moratorium on shark fishing every summer—peak pupping season for white sharks. Both approaches help conserve sharks, and the study illustrates the added benefits of inshore gillnet measures for survival of juvenile white sharks.

Coauthor Oscar Sosa-Nishizaki, a professor at Mexico’s Ensenada Center for Scientific Research and Higher Education, agrees. Oscar has worked with the Monterey Bay Aquarium since 2002, contributing to research in places like Vizcaino Bay—a nursery area for young white sharks.

“It’s very important to work with the fishermen,” he says. “We want to know whenever they incidentally catch a white shark.”

Another best practice might be encouraging fishing crews to check their gillnets more than once each day, so a shark accidentally entangled in the net doesn’t stay there for long. This small step can cut a shark’s chance of death by gillnet in half.

“We have learned that if fishermen check their nets frequently, white sharks are quite hardy,” Sal says. ��If released promptly, there’s a good chance they’ll survive.”

“This research suggests the importance of a collaborative approach to management in California and Mexico, and opportunities to innovate on best practices that can support fishermen, research and protections for white sharks,” he adds.

—Daniel Potter

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sohannabarberaesque · 6 years ago

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Moth Mondays with the Funtastic World of Hanna-Barbera: Squiddly Diddly "himself"

Not an easy one to describe categorically, but on the other hand, there's bound to be times when the decline and imminent fall of Bubbleland prompts opportunities for misadventures hilarious galore. Witness:

So what exactly are you reduced to when the marine-life park you reside in is essentially "going down the tubes" big time and your status in the face of an imminent closing and sale of the land is equally uncertain?

Myself ... I happen to be creative in taking my share of the madcap side of underwater in the open waters--at least close to shore. Take, for example, one time not too long back (perhaps it was a month and a half ago) where the illness of Chief Winchley (otherwise known as my supervisor) was getting rather prolonged to the point where attendance at Bubbleland was likely to take a serious hit based solely on whispers and rumours, even leading some to spread the story that Bubbleland had closed or was close to it. Which was enough to have yours truly partner, in a way, with a certain Monterey Jill, a resident sea otter at Bubbleland I've taken something of an attachment to, in some near-shore underwater discovery.

Discovery, mind you, being close to a certain Redondo Beach at a spot known once as Moonstone Beach, called that because, at one time, a lot of moonstones and other quasi-precious gemstones washed up on the sands, ready for visitors to pick up and take as souvenirs. No wonder the old Balloon Route Trolley Excursions of Southern California made a stop at Moonstone Beach for that purpose ... only in our case, such was going to be underwater, barely a quarter mile from shore.

Now, otters do happen to have some pretty resilient claws which are capable of opening clamshells, oysters and abalone ... but as for digging the sand bottom of a nearshore section of Moonstone Beach, hoping one could still extract such gems in what's otherwise a semi-popular surf break--now THAT was something of a try! (I delegated the digging to Monterey Jill because of her claws, whereas I have mere tentacles that aren't quite up to the task.) Still, it was rather early morning, the waters were still rather dank and you had the marine layer making things a little crazy ... and yet I wonder how Monterey Jill was able to discern the likelihood of possible bits of moonstone and similar in the ocean sands off what used to be Moonstone Beach, just like they can find seafood for their meals and open the clam shells rather deftly besides.

And under such conditions, to boot. Let alone the chilly waters of the pre-dawn, especially before what surfers call "the dawn patrol" begin hitting the waves.

I have heard a few Native American creation legends which involve otters and beavers digging at the bottom of a lake to find enough earth which would then evolve into Earth the planet ... but boy, just give her some time and an inate skill at detecting moonstone and suchlike, and she's stirring up the bottom like crazy, eventually hitting a couple of choice specimens rather suddenly. Considering my frame and everything, mind you, we agreed to collect only a couple pieces so as not to cause serious problems swimming with the incoming tide and carrying such rare oceanic gems besides. (For comparison, they were about the size of "big ring" marbles.)

And you wonder, considering the possible rarity of such thanks to all the moonstone picked up from Moonstone Beach well into the World War I period and taken as souvenirs back to Iowa, say, once the tourists headed back, such would seriously have value fashioned into kitschy jewellry. Especially if the value were enough to at least keep Bubbleland open.

Or maybe not, in which case I could set up a modest diving school off K-38 in Baja....

"... and that's the story from The Moth"

(The preceding is an independent fanfic feature having no official connexion or association with The Moth. For more information, please to visit their website ... and tune in to The Moth Radio Hour weekends on your local public radio station; check your local radio listings for the day and time.)

#fanfic #hanna barbera #moth monday #the moth #crossover #squiddly diddly #bubbleland #moonstone #moonstone hunting #underwater treasure hunting #moonstone beach

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perfectirishgifts · 4 years ago

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Sunflower Sea Star Deemed ‘Critically Endangered’ After Disease Claims 90% Of The Population

New Post has been published on https://perfectirishgifts.com/sunflower-sea-star-deemed-critically-endangered-after-disease-claims-90-of-the-population/

Sunflower Sea Star Deemed ‘Critically Endangered’ After Disease Claims 90% Of The Population

Sunflower Star on the Olympic Coast of Washington

Earlier this week, the sunflower sea star was listed as Critically Endangered by the International Union for Conservation of Nature (IUCN), which maintains a “Red List of Threatened Species”.

A decade ago, this many-legged sea star was a common sighting in coastal waters from Alaska to Baja California. But, when ocean temperatures increased along the west coast from 2014-2016 during “the warm Blob” and El Niño, a pathogen that causes sea star wasting disease took hold and many sea star species perished. The sunflower star was particularly affected – while several species have since recovered, this underwater behemoth is still sparse. Using more than 60,000 surveys and 30 datasets, scientists estimate that a staggering 5.75 billion sunflower stars have died from this disease, which comprises over 90% of their global population.

With the sunflower star nearing extinction, west coast kelp forests are on the verge of losing a key predator that has helped keep these ecosystems in check. Kelp forests are currently grappling with booming urchin populations, and it is more important than ever to help protect and restore sunflower star populations. Thus, The Nature Conservancy and University of Washington are partnering to establish a captive breeding program with the option for re-introducing individuals to the wild.

“The sunflower star was the most susceptible of the twenty starfish species affected by a multi-host pathogen and has rapidly gone from being the most common subtidal starfish on the US west coast to critically endangered,” said Dr. Drew Harvell, a Professor of Marine Ecology at Cornell University and key player in the sunflower star’s saga, “This highlights the impacts disease can have on stability of our nearshore ecosystems.”

Sunflower Star (Pycnopodia helianthoides) entangled in seagrass

From Science in Perfectirishgifts

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sciencespies · 4 years ago

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Sunflower Sea Star Deemed ‘Critically Endangered’ After Disease Claims 90% Of The Population

https://sciencespies.com/news/sunflower-sea-star-deemed-critically-endangered-after-disease-claims-90-of-the-population/

Sunflower Sea Star Deemed ‘Critically Endangered’ After Disease Claims 90% Of The Population

Sunflower Sea star (Pycnopodia Helianthoides). It is among the largest sea stars in the world and … [+] has a maximum arm span of one metre. (Photo by: Universal History Archive/UIG via Getty Images)

Getty

Earlier this week, the sunflower sea star was listed as Critically Endangered” by the International Union for Conservation of Nature (IUCN), which maintains a “Red List of Threatened Species”.

With the sunflower star nearing extinction, west coast kelp forests are on the verge of losing a key predator that has helped keep these ecosystems in check. With kelp forests currently grappling with booming urchin populations, it is more important than ever to help protect and restore sunflower star populations. Thus, The Nature Conservancy and University of Washington are partnering to establish a captive breeding program with the option for re-introducing individuals to the wild.

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#News

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introcut · 4 years ago

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#Lingcod are not true cod & are not related to Pacific cod or pollack. Instead, lingcod are the largest members of the #greenling family. they are in the same group of fishes as #sablefish, Pacific #rockfish and #scorpionfish. Adult lingcod average 10 lbs but they can grow to over 80 lbs and measure 60 inches in length. The head and mouth of a lingcod are large, and the mouth holds 18 big, sharp teeth. The head does not have scales. Lingcod are found only on the west coast of North America, from the Alaska Peninsula and Aleutian Islands south to Baja California. They normally live nearshore around rocky reefs from depths of 30 to 330 ft. Adult lingcod are voracious predators and grow rapidly. They feed on invertebrates and fish, including other lingcod who are nearly their same size. Lingcod continue growing until they are 12 to 14 years old. #pacificnorthwest #oceanlife #aquaticlife #fish #pugetsound #sealife https://www.instagram.com/p/CFydJQ4piNE/?igshid=1k0g1nqao9kd6

#lingcod #greenling #sablefish #rockfish #scorpionfish #pacificnorthwest #oceanlife #aquaticlife #fish #pugetsound #sealife

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okeanisorg-blog · 5 years ago

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New Post has been published on http://www.okeanis.org/sickening-truth-behind-holiday-park-dolphins-brutally-hunted-in-the-wild-world-news-mirror-online/

Sickening truth behind holiday park dolphins brutally hunted in the wild - World News - Mirror Online

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Nereis Project

The sea otter (Enhydra lutris) is the only member of the genus Enhydra. It is the largest member of the family Mustelidae which includes approximately 70 species; the sea otter is also the smallest marine mammal. The sea otter is limited in distribution to nearshore waters of the northern Pacific Ocean. Sea otters once ranged from northern Japan to the Alaskan peninsula and along the west coast of North America to Baja California in Mexico. Until the 1700s, sea otters were abundant throughout the waters of the North Pacific and for centuries native groups, such as the Aleuts, hunted them. During this time, the worldwide sea otter population probably numbered 150,000 to 300,000 animals. By the mid-1700s, Russian hunters had coerced the Aleuts to exploit sea otters for the fur trade, and the once abundant sea otter population plummeted. The otters that remained were chased down by English, French, Japanese and American traders. By the 1900s, the sea otter was nearly extinct with only 1,000 to 2,000 left. Only 13 remnant sea otter colonies existed from Russia to Mexico when the International Fur Seal Treaty, which banned the hunting of sea otters and fur seals, was established in 1911 (Kenyon 1975, 1981; Johnson 1982; Riedman and Estes 1990).

Based on morphological differences in color, body and skull sizes, three sub-species of sea otters have been proposed historically: Enhydra lutris lutris from the western Alaska archipelago, Enhydra lutris kenyoni from Prince William Sound, Alaska, and Enhydra lutris nereis, the California or southern sea otter (Anderson et al. 1996). Cronin et al. (1996) proposed the classification of otters from the Kuril Islands as Enhydra lutris gracilis but this nomenclature has not been officially recognized.

The status of sea otter populations is currently an issue of concern at the international level. Except for the California sea otter population, which has never increased more than 5.5% annually, all other populations have increased up to 20% per year from the time of their re-establishment in the late 1960s through the late 1980s (Estes 1990). Since then, there have been new and unexplained declines throughout the majority of the southwest Alaska stock which is now proposed as “threatened” under the Endangered Species Act (USFWS 2001; Burn et al. 2003; Doroff et al. 2003). As of summer 2003, the number of sea otters in the Aleutian archipelago has declined to about five-percent of its estimated pre-decline abundance and the rates of decline in this region appear to be increasing at an alarming rate (Maldini et al. 2004).

Once ranging from Baja California, Mexico all the way to Oregon and the southeast Alaska border, the southern sea otter is now confined to waters along the central California coast from Point Aňo Nuevo, Santa Cruz County south to Purisima Point, Santa Barbara County (Wilson et al. 1991). A small experimental population has been re-introduced at San Nicolas Island, one of the Channel Islands in Ventura County with mixed success (Jameson et al. 1992).

By the 1930s, the California sea otter population consisted only of a small group of 50 to 300 sea otters restricted to the Big Sur coast of central California. Under the protection of the International Fur Seal Treaty, this small population began a slow and steady climb from nearly extinct to a fairly stable population. From the mid 1970s to the mid 1980s, the southern sea otter population began to decline once again. In 1977, the southern sea otter was listed as “threatened” under the Endangered Species Act. About 1,000 sea otters died over a 10 year period due to entrapment in gill nets. When gill net legislation was passed in the late 1980s requiring gill nets to move farther off shore, the sea otter population began to grow again until the mid-1990s (Siniff and Ralls 1988; Estes 1990; Estes et al. 1995; Ralls et al. 1996).

From 1995 until the present, southern sea otter numbers have declined in five out of the last six years. Some of the possible causes include entrapment in fisheries gear, disease, food limitations, and habitat loss and degradation due to contaminants (Wendell et al. 1986, Estes 2003, Miller et al. 2005). Sea otter protection is a source of ongoing conflict between the California shellfish (abalone, sea urchin, crab, lobster) industries and conservation groups (Estes and VanBlaricom 1985). While fishermen view the shellfish eating sea otter as a threat to their livelihood, conservation groups and scientists see the sea otter as a keystone species because their activity is central to the nature of their ecosystem. By consuming large numbers of sea urchins, sea otters have been shown to be instrumental in maintaining the health and persistence of kelp forest habitats in Alaska waters (Estes et al. 1978; Estes et al. 1982). Without the balancing presence of sea otters, sea urchins end up overgrazing kelp forests and creating underwater deserts known as “urchin barrens.” A sea otter’s effect on the ecosystem is disproportionate to how many sea otters there are. Very few sea otters can have a large effect.

The California sea otter population, currently at about 2,000 individuals, is well below the estimated carrying capacity (16,000 animals) for the State of California. Because of its small size, sluggish growth, and numerous perceived threats, the California sea otter population is also listed as “threatened” under the US Endangered Species Act. High mortality rates appear to be largely responsible for the sluggish growth and abundance fluctuations (Estes 2003, Hanni 2003, Kreuder et al. 2003). The causes of this mortality are not well understood, and are being studied both by examining stranded carcasses and by conducting detailed longitudinal studies of living sea otters (Kreuder et al. 2003). One poorly understood threat is toxoplasmosis, an often lethal and otherwise debilitating infection caused by Toxoplasma gondii, a micro-organism that has as intermediate host wild, feral and domestic cats. Oocysts are released in cat feces and can persist in the environment for up to two years. The main infection mechanisms is thought to be the ingestion of oocysts either directly from seawater or concentrated in filter feeding invertebrates which are the otter’s staple diet.

The Importance of Male Areas

California sea otters are concentrated in numbers around Monterey Bay where several territorial male areas are found in prime feeding habitat, especially in dense kelp forest areas. These territories are held long-term by males fit enough to maintain them and the chance for young males to supplant the extant territorial males are infrequent. Young animals not holding a territory and recently weaned pups ousted from their natal area by the adult male tenant, and probably father, generally congregate in “male areas” which are found at the periphery of the sea otter range, and are supposed to be the areas where expansion into new unoccupied territories should occur. Otherwise, these young males may eventually supplant older adults in extant territories.

Not much effort has been devoted by researchers into understanding the dynamics of male areas and their importance to the health and increase of the sea otter population in California. High mortality in the young adult population, both male and female, has been advocated as a potential threat to the longevity of the California population and, as mentioned before, disease may currently play a large role in the mortality rate.

Males in male areas tend to rest in large rafts which are dynamic social units. The social role of male rafts has not been investigated. We hypothesize that male rafts play an essential role in developing young males’ fitness potential by providing “role modeling” by older mature males, which are generally found interspersed with large number of immature males and young adults. Rafts also provide shelter and potential protection by predators using the safety in number model. In addition, we propose that the social skills acquired by male otters in the social context of male areas are as important as the skills acquired by the pup form its mother up to weaning. Rafts provide tactile stimulation to young otters that have been in constant body contact with their mother up to weaning, and are a forum for mock fighting which helps develop the skills necessary to confront territorial males when young adults are ready to claim a territory.

Elkhorn Slough and Sea Otter Population Dynamics

An important male area in Monterey Bay is located at the center of the bay, around the coastal shallow waters between Moss Landing and the Pajaro River mouth and, principally, inside Elkhorn Slough, a seasonal estuary and the second most important wetland area along the California coast. Elkhorn Slough is part of the Monterey Bay National Marine Sanctuary and is a National Estuarine Research Reserve.

The first documented invasion of Elkhorn Slough by male sea otters occurred between 1994 and 1995 (Maldini-Feinholz 1998). Up to 4% of the California population and a more significant percent of the juvenile male sea otter population used Elkhorn Slough during the past 10 years making the slough a significant sea otter habitat along the California coast (Kieckhefer et al. 2004).

Between 1994 and 2001, the research teams associated with this study counted up to 81 otters using the slough. From a maximum mean number of 52 otters in 1998, otter counts then dropped sharply to 27 in 2001, and have remained low until recently (Hoffman 2003, Maldini unpublished data). Aerial surveys in 2002 and 2003 showed an increase in otter counts in offshore areas adjacent to Elkhorn Slough, suggesting that the otters had relocated (Kieckhefer 2004). In 2006, we documented up to 83 animals in using Elkhorn Slough for resting, although the majority of the population still foraged mainly in the harbor channel and in the nearshore sandy bottom coastline rather than in the main slough channel as in the past (Maldini unpublished data).

The long term monitoring of sea otter use of Elkhorn Slough as a foraging area revealed patterns of sea otter invasions of the main channel, with animals penetrating up to five miles inland to the limit of the distribution of clam beds in the estuary, and subsequent retreat from the main channel as food resources were depleted (Kieckhefer et al. 2004). In soft-bottomed habitats like the Elkhorn Slough area, sea otters prefer clams, innkeeper worms and other burrowing invertebrates that live in mud (Kvitek and Oliver 1986; Anderson and Kvitek 1987; Jolly 1997, Maldini et al. 2010 click here for paper). It is still unclear whether prey may have decreased due to over-foraging by otters, or by severe erosion of the slough banks due to tidal flow, which changed the substrate from mud to bedrock. Some researchers theorize that the unusually high number of otter mortalities in 2003 may have been related to the slough otters’ diet shift to offshore crabs (predominantly Dungeness). In addition, high levels of domoic acid (a fatal neurotoxin produced by oceanic diatoms) recorded during this time period may have played a significant role in sea otter mortality in 2004 (Kieckhefer, unpublished data).

Human-Related Disturbance and Habituation

In the last decade there has been an approximately 12% growth in total population in Monterey Bay (U.S. Census Bureau, 2005 American Community Survey). In addition, infrastructure development and increase in eco-tourism and recreational activities have increased access to many of natural areas in Monterey Bay.

Tourism activity in Elkhorn Slough has increased dramatically from 1990 to today with Kayak Outfitters increasing their business activities and tours becoming more popular especially on the week-ends. Boat traffic is also high in Moss Landing Harbor, at the mouth of the slough, and occasionally, small fishing vessels use the slough for recreational activities (Rodriguez et al. 2010 click here for poster).

Sea otters rest and forage right in the midst of intense human activity spending a large portion of their time budget in the middle of the boat channel and near the main launch ramp at Moss Landing Harbor. In the last couple of years, residents and our research team have documented an increase in human-sea otter interactions, with animals climbing on kayaks, coming to shore to chase people, and showing little fear of humans while in the water. Otters can inflict serious bite injuries if molested and rehabilitated animals released into the wild have been documented to attack or harass people or to beg for food.

Little is knows about how habituation will impact the animal fitness in the wild and whether these patterns of habituation will result in detrimental consequences for sea otters which will have to be removed from the area if they become a hazard to humans. Conversley, the consequence of human activities on the sea otter behavioral budget and resting patterns has been poorly studied. Moss Landing Harbor is an ideal location to monitor human-sea otter interactions and the potential consequences of human related traffic and activities on sea otter behavioral budgets, especially in relation to resting activities (Rodriguez et al. 2010 click here for poster).

Sea otters spend a considerable amount of time foraging to compensate for their high metabolic rate and can consume up to 25% of their body weight every day. An increase in energy expenditure by sea otters will result in increased metabolic requirements and therefore in increased feeding rates. Resting is a way to save energy. Resting in a raft may also provide additional insulation from severe weather conditions. When sea otters rest their body is raised as far out of the water as possible and their paws are kept out of the water and extended upward to keep them dry. This saves additional energy. The most cost efficient resting behavior is probable obtained by hauling out onto shore and becoming completely dry (Maldini et al. 2012 click here for paper).

Every time resting otters are disturbed, the animals roll out of sleep and often start moving away from the disturbance or dive if startled. This causes the animal to become wet and therefore consuming more energy to stay warm.

Our hypothesis is that, as a consequence of human activities, sea otters spend longer times in activities other than resting causing the animals to have to forage longer or more efficiently to make up for the loss in calories. In the long-run, this upsets the otter metabolic cycle and potentially affects them physiologically.

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portlandstateresearch · 7 years ago

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David Percy, Geology instructor, coauthored “Origins of late- Pleistocene coastal dune sheets, Magdalena and Guerrero Negro, from continental shelf low-stand supply (70–20 ka), under conditions of southeast littoral- and eolian-sand transport, in Baja California Sur, Mexico,” published in Aeolian Research 28:13-28 · October 2017DOI: 10.1016/j.aeolia.2017.07.003

Abstract: Shallow morpho-stratigraphic sections (n = 11) in each of two large coastal dune sheets including the Magdalena (7000 km²) and Guerrero Negro (8000 km²) dune sheets, from the Pacific Ocean side of Baja California Sur, Mexico, have been analyzed for dune deposit age. The shallow morpho-stratigraphic sections (∼2–10 m depth) include 11 new TL and 14C ages, and paleosol chronosequences, that differentiate cemented late Pleistocene dune deposits (20.7 ± 2.1 to 99.8 ± 9.4 ka) from uncemented Holocene dune deposits (0.7 ± 0.05 to at least 3.2 ± 0.3 ka). Large linear dune ridges (5–10 m in height) in the dune sheet interiors trend southeast and are generally of late Pleistocene age (∼70–20 ka). The late Pleistocene dune deposits reflect eolian transport of marine sand across the emerged continental shelf (30–50 km southeast distance) from low-stand paleo-shorelines (−100 ± 25 m elevation), which were locally oriented nearly orthogonal to modeled deep-water wave directions (∼300° TN). During the Holocene marine transgression, onshore and alongshore wave transport delivered remobilized shelf-sand deposits to the nearshore areas of the large dune sheets, building extensive barrier islands and sand spits. Submerged back-barrier lagoons generally precluded marine sand supply to dune sheet interiors in middle to late Holocene time, though exceptions occur along some ocean and lagoon shorelines. Reactivation of the late Pleistocene dune deposits in the dune sheet interiors lead to generally thin (1–3 m thickness), but widespread, covers of Holocene dune deposits (0.41 ± 0.05 to 10.5 ± 1.6 ka). Mechanical drilling will be required to penetrate indurated subsoil caliche layers to reach basal Pleistocene dune deposits.

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oceanforsharks · 7 years ago

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One of the most charismatic shark species is the leopard shark, Triakis semifasciata, with its elongated body, flattened head, dual dorsal fins of nearly equal size, striking dark saddle-like spots against a sandy or silver background, and a stark white belly (Nosal et al., 2013; Tricas et al., 1997). These stunning features are why the leopard shark are one of the most commonly featured sharks in zoos and aquariums (Delius, 2015).

Flannery, A. (Photographer). (2017 June 12). Leopard Shark at CZS-Brookfield Zoo [Digital Image]. Original Content.

For their commonality in zoos and aquariums, these meso-predators are found in a surprisingly small region just off the Pacific Coast of the United States, reaching from Oregon to Northern Mexico (Hopkins & Cech Jr, 2003; Lewallen, Anderson, & Bohonak, 2007; Smith, 2001, 2007). Leopard shark tend to stay close to shore in the shallow bays and estuaries along the inter-tidal regions (Smith, 2001, 2007) where they actively use the rise and fall of the tides to navigate through their habitats, finding food, shelter, pupping grounds, and even each other when it is time to aggregate for reproduction (Ackerman, Kondratieff, Matern, & Cech, 2000; Carlisle & Starr, 2009, 2010).

Skipper, G. (Photographer). (2015 December 6). Leopard sharks! bolsa chica reserve [Digital Image]. Retrieved from https://www.flickr.com/

Leopard sharks tend to aggregate together in social groups with individuals of similar size, age, and gender (Hight & Lowe, 2007). These social groups usually consist of juveniles, mature females of similar size, and mature males of similar size. However, what female leopard sharks are known to draw crowds each year between June and September in the warmer waters of Southern California and Northern Mexico when they aggregate in the shallows to pup (Jacoby, Croft, & Sims, 2012; Smith, 2007; Smith, 2001). Shallow embankments such as estuaries have been documented to serve as nurseries for several species of elasmobranchs (Carlisle & Starr, 2009) possibly because they provide abundant prey resources, nutrient rich waters, and low predation risks to the pups (Duncan & Holland, 2006; Knip, Heupel, & Simpfendorfer, 2010). If you ever get the chance to visit La Jolla, California in the summer months, take a snorkel just beyond the surf line. These sharks are timid so approach slowly. Trust me it is well worth it!

Rogeruzun (2016 September 16). Leopard Shark Invasion (4K UHD) [Video Clip]. Retrieved from https://www.youtube.com/

Like other near shore elasmobranch species, leopard sharks are threatened by human activity (Knip et al., 2010). In a California study of wetland destruction over the past century, it has been estimated that nearly 91% of all estuarine habitat in California has been altered or all together destroyed by anthropogenic forces (Larson, 2001). With their limited habitat range and dependence on these estuary environments throughout their life history, leopard sharks are particularly vulnerable to the loss of these critical environments (Carlisle & Starr, 2009). Some studies suggest that the habitat erosion of the California coast line continues to be high due to agriculture, development, and pollution (Smith, 2001, 2007), and have a potentially damning effect on the populations of leopard sharks off the coast of California (Carlisle & Starr, 2009). Earlier this year, leopard sharks were found in mass strandings across California from January through May. Researchers are still looking into the exact cause, however it has been suggested that terrestrial run off from increased storm activity may have been the catalyst (Pelagic Shark Research Foundation, 2017).

Pelagic Shark Research Foundation (Photographer). (2017 May 15). Stranded leopard shark [Digital Image]. Retrieved from https://www.facebook.com/

DNA sampling of leopard sharks in California waters have determined that genetic diversity is lower than previously anticipated because there appears to be seven distinct populations that are not interbreeding with the other populations (Lewallen et al., 2007). At present the IUCN has the leopard shark listed as “Least Concern” on the Red List of Threatened Species (Carlisle, Smith, Launer, & White, 2015). Although it has been suggested that due to their long gestation period, slow growth rates, limited genetic diversity, and delayed sexual maturity they should be declared “Vulnerable” (Smith, 2001, 2007).

ElkhornSlough.org (Author). (n.d.). Working up a leopard shark [Digital Image]. Retrieved from http://www.elkhornslough.org/

Shark Stats

Family: Triakidae (houndsharks)

Length: 6.5 feet maximum (1.9 m)

Weight: 40 lbs (18.4 kg)

Habitat: Shallow coastal waters, bays, kelp beds, estuaries

Depth: Surface to 13 feet (4 m)

Reproduction: Ovoviviparous

Gestation: 10 to 12 months

Litter Range: 4 – 33 pups

Home Range: temperate water in the eastern Pacific, coastal U.S. from Oregon to Baja, Mexico, most commonly found along California

Diet: Prey includes bottom fishes and invertebrates

IUCN Status: Least Concern

(Skomal, 2016; Carlisle, Smith, Launer, & White, 2015)

I hope you enjoyed learning about one of my favorite shark species! I feel like I say that about every shark species, but these guys have been the focus of some of my early graduate work. They are also the first shark species I took my husband snorkeling with. (My mother-in-law was soooooo happy with me!) I absolutely love this species and I truly recommend to anyone that is in southern California in the summer months to try heading out to La Jolla for an afternoon. It is an unforgettable experience!

Flannery, A. (Photographer). (2016 June). Grad studies and leopard sharks [Digital Image]. Original Content.

If you haven’t checked out the previous Feature Species, the Great Hammerhead, be sure to check it out! Leave me a comment and let me know what species you’d like to learn more about! I’d love to hear your thoughts! Until next time finatics!

Featured Image Source

San Diego Zoo (Author). (2017 April). Leopard Shark [Digital Image]. Retrieved from http://adminanimals.sandiegozoo.org/

Literature Cited

Ackerman, J. T., Kondratieff, M. C., Matern, S. A., & Cech, J. J. (2000). Tidal influence on spatial dynamics of leopard sharks, Triakis semifasciata, in Tomales Bay, California. Environmental Biology of Fishes, 58(1), 33–43.

Carlisle, A., Smith, S., Launer, A., & White, C. (2015). Triakis semifasciata. The IUCN Red List of Threatened Species. Retrieved June 24, 2016, from http://www.iucnredlist.org/details/39363/0

Carlisle, & Starr. (2009). Habitat use, residency, and seasonal distribution of female leopard sharks Triakis semifasciata in Elkhorn Slough, California. Marine Ecology Progress Series, 380, 213–228.

Carlisle, & Starr. (2010). Tidal movements of female leopard sharks (Triakis semifasciata) in Elkhorn Slough, California. Environmental Biology of Fishes, 89(1), 31–45.

Delius, B. (2015). Triakis semifasciata. Retrieved July 10, 2016, from https://www.flmnh.ufl.edu/fish/discover/species-profiles/triakis-semifasciata

Duncan, K. M., & Holland, K. N. (2006). Habitat use, growth rates and dispersal patterns of juvenile scalloped hammerhead sharks (Sphyrna lewini) in a nursery habitat. Marine Ecology Progress Series, 312, 211–221.

Hight, B. V., & Lowe, C. G. (2007). Elevated body temperatures of adult female leopard sharks, Triakis semifasciata, while aggregating in shallow nearshore embayments: Evidence for behavioral thermoregulation? Journal of Experimental Marine Biology and Ecology, 352(1), 114–128.

Hopkins, T. E., & Cech Jr, J. J. (2003). The influence of environmental variables on the distribution and abundance of three elasmobranchs in Tomales Bay, California. Environmental Biology of Fishes, 66(3), 279–291.

Jacoby, D. M. P., Croft, D. P., & Sims, D. W. (2012). Social behaviour in sharks and rays: Analysis, patterns and implications for conservation. Fish and Fisheries, 13(4), 399–417.

Knip, D. M., Heupel, M. R., & Simpfendorfer, C. A. (2010). Sharks in nearshore environments: models, importance, and consequences. Marine Ecology Progress Series, 402, 1–11.

Larson, E. J. (2001). Coastal wetlands-emergent marshes. California’s Living Marine Resources: A Status Report. California and California Department of Fish and Game, Sacramento, California, 483–486.

Lewallen, E. A., Anderson, T. W., & Bohonak, A. J. (2007). Genetic structure of leopard shark (Triakis semifasciata) populations in California waters. Marine Biology, 152(3), 599–609.

Nosal, A. P., Cartamil, D. C., Long, J. W., Lührmann, M., Wegner, N. C., & Graham, J. B. (2013). Demography and movement patterns of leopard sharks (Triakis semifasciata) aggregating near the head of a submarine canyon along the open coast of southern California, USA. Environmental Biology of Fishes, 96(7), 865–878.

Pelagic Shark Research Foundation (2017). San Francisco Bay, Stranding Report Update for late May and June 1, 2017. Retrieved from https://www.facebook.com/Pelagic-Shark-Research-Foundation-167200017410/?ref=page_internal

Skomal, G. (2016). The Shark Handbook: The Essential Guide for Understanding the Sharks of the World. (2nd ed.). Kennebunkport, ME: Cider Mill Press.

Smith, S. (2001). California’s Marine Living Resources: A Status Report. California Department of Fish and Game.

Smith, S. (2001). Leopard shark. California’s Marine Living Resources: A Status Report, (December), 252–254.

Smith, S. (2007). Leopard shark. Status of the Fisheries Report, (14), 1–7.

Tricas, T. C., Deacon, K., Last, P., McCosker, J. E., Walker, T. I., & Taylor, L. (1997). The Nature Company Guides: Sharks and Rays. (L. Taylor, Ed.). Hong Kong: The Nature Company, Time Life Books.

Featured Species: Leopard Shark (Triakis semifasicata)

Featured Species: Leopard Shark (Triakis semifasicata) One of the most charismatic shark species is the leopard shark, Triakis semifasciata, with its elongated body, flattened head, dual dorsal fins of nearly equal size, striking dark saddle-like spots against a sandy or silver background, and a stark white belly (Nosal et al., 2013; Tricas et al., 1997).

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nitedreamerdesigns · 7 years ago