Viaje a las profundidades del Océano (VIDEO) + Extrañas criaturas marinas (FOTOS)

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  Pero, ¿qué es un Océano? U n océano es una enorme masa de agua salada que representa un importante ecosistema para el equilibrio ecológico de la Tierra y que constituye el  71% de la superficie terrestre , gracias a los 360,132,000 km² de su extensión. Y,  ¿cuántos océanos existen? Lo que cubre gran parte de la superficie de la Tierra, es en sí, un solo océano. Es decir, una sola masa de agua. Para un mejor estudio, el hombre dividió esta enorme masa en 5 partes de acuerdo a su ubicación geográfica. Por ello, la expresión “los océanos”, es correcta. Importancia de los océanos *Absorben entre un 25 y 30% del dióxido de carbono emitido a la atmósfera, por lo que Equilibran el clima de toda la Tierra. *Representan numerosos ecosistemas para diversas formas de vida animal, vegetal, bacteriana, protista y fúngica. *Son hogar para miles de especies, conocidas y aún desconocidas. Existen aproximadamente 250,000 especies conocidas, pero se cree que puedan haber 750,000 más. *Proveen fuentes

How Reptiles are affected by Climate Change?

Reptiles (snakes, lizards, turtles and crocodiles), like all invertebrates, fish and amphibians, are Ectotherms. This means that its metabolism (the set of life-sustaining chemical reactions in organisms) is temperature dependent. 
Besides, the sex of reptiles is determined by temperature and not by chromosomes (as in the case of humans where sex is determined by the chormosomes carried on the sperm cells). 

Knowing these data, what do you think will happen with reptiles if the constant increase in temperature worldwide continues?. (Fell free to leave your opinion)
Types of Retiles. Source: socratic.org

Allow me to give you just an example: In turtles, a cooler incubation temperature of the eggs activates a gene that causes testicles to develop instead of ovaries. On the contrary, a high incubation temperature (as is currently the case with global warming) causes more female turtles to develop than males causing an imbalance in the turtle population on a global scale. Below these lines I present a brief summary of a very interesting article published by the United States Department of Agriculture (USDA). For further information and bibliography, I invite you to follow the link I added at the end of this blog. Hope you Enjoy it!

Article:

Many reptiles are highly sensitive to the altered temperatures that may result from climate change due to their ectothermy which requires that they rely on ambient environmental temperatures to maintain critical physiological processes. Due to the variety of snakes, lizards, crocodilians, and turtles in our world (traditionally classified as reptiles), and because climate change data and projections vary with location, it will be important to consider each species and location separately when considering the potential effects of altered climate on these animals. 

In temperate zones, lizards are thought to be highly vulnerable to climate change. Their reproduction is closely tied to narrow windows of time in the spring and summer when suitable temperature and moisture regimes are available for critical natural history activities, such as foraging and mating. Altered weather conditions during these seasons may result in frequently recurring "bust" years of reproductive failure. Other climate effects on lizard survival include mortality associated with warm spells in winter (8), interacting effects of altered vegetation communities, fire regimes and invasive species (9), and potentially disease (10).
Snakes are very closely related to lizards, and these effects may hold true for them as well. 

Climate change concerns for turtles and crocodilians are three-fold. First, these mostly aquatic species may encounter altered habitats and increased habitat fragmentation with altered climate. In this regard they share many concerns with amphibians, such as sensitivity to changes in water availability and its’ thermal properties. Second, turtles and alligators have temperature-sensitive sex determination: cooler temperatures may produce nests of only males; warmer temperatures may produce nests of only females. Temperature changes in a local area may have the effect of altering the sex ratios of populations - potentially affecting future reproduction and over time compromising their evolutionary fitness. Third, coastal species such as the American Alligator and Crocodile are susceptible to an increasing frequency or intensity of storms caused by increases in ocean temperatures. Storm surges can displace or drown animals, and dehydrate them by salt water intrusion into freshwater habitats. 

Options for Management
For reptiles, management is of paramount concern to maintain and restore existing habitats, augment acreages of intact habitat blocks, and adapt management actions to reduce environmental stressors. 

Because microclimates can be readily manipulated with local land management activities, people can actively engineer a future for some of these organisms, especially when their environments are already highly altered due to human activities.

Invasive plant species and most human disturbances can alter local- to landscape-scale habitats and microclimates, which can have consequent effects on reptiles. Non-native vegetation may have different physical structure and cover, hindering reptile daily activities, and subsequently altering critical life history functions and reptile survival, and negatively influencing dynamics of interacting communities. 

Open habitat management may be needed to forestall encroaching vegetation, especially non-native plants, or to mitigate human disturbance (e.g., agricultural or energy development). Meadow shrub and tree control may be needed to retain sun-exposure. Riparian buffers may retain near-water refugia. For turtles or other water-dependent reptiles, manipulation of hydroperiod at sites by site excavation and riparian buffer management are considerations. 

Substrate management may be needed for several types of reptiles: rock outcrops and talus are complex refugia for lizards and snakes and may need protection or augmentation; rocky pond edges provide basking sites and antipredation refugia for turtles. Some species need specific substrate types, or rely on existing burrows created by other animals; these need consideration if climate change alters landscape-scale habitat distribution. Traditionally used snake hibernacula may need special protection. Management measures taken to maintain natural fire regimes and control invasive plants might also benefit reptiles. Altered fire regimes may change refugia, reduce cover and expose animals to heightened predation, and invasive plants may exacerbate climate-linked fire patterns.

Managers can facilitate the movement of reptiles by providing corridors between needed habitats that support complex reptile life histories: breeding, foraging, overwintering, anti-predation, and basking habitats can all differ. Corridors between overwintering hibernacula and foraging areas, or between upland nesting sites and aquatic breeding sites are a particular concern because these can be inadvertently affected by roads or development. 

If stop-gap measures are needed for rare species faced with extinction, the more costly methods of Reintroduction, Relocation, Translocation, and Headstarting (RRTH) may be considered. Broad-scale policies directed at vulnerable site protections warrant consideration.

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