Green crab (Carcinus maenas)

Carcinus maenas better know by its common name green crab is originally native to Europe and is now dispersed globally with records of occurrence in Australia, Hawaii, Sri Lanka, South Africa, along the Atlantic and Pacific coasts of North America, and the Atlantic coast of South America

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 It was first introduced into the U.S in 1817 by ship's ballast water  and is now the most abundant crab species with the females being able to produce up to 185,000 eggs per sponge.Green crabs eat a wide variety of prey organisms and can significantly reduce populations of native clams and crabs in areas where they have become established. Their ability to out compete native species for food resources, high reproductive capacity, and wide environmental tolerances lend them the capacity to fundamentally alter community structure in coastal ecosystems. Their main prey ranges from clams, mussels, oysters and gastropods. 

The economic cost of these invasive species are very high as they reduce the native species populations and reduce income of fisher men who depend on the ocean to live.

Zebra mussels (Dreissena polymorpha)

Zebra mussels also know as Dreissena polymorpha got their name from the stripped pattern on their shell but it also varies and causes there to be no stripes and just light or dark colored shells.

They are native to Russia and were first introduced into the United States in the 1980's by transoceanic ships from western European ports discharging ballast water into lake St. Clair. Since their arrival zebra mussels have disrupted the natural  aquatic food chain of many bodies of water, also just like other mussels zebra mussels attach to hard surfaces like pipes

 and also the native mussels.

 with the spreading of these mussels the population of native mussels have severely reduced.
There are now  millions of these mollusks, and they have a rapid rate of reproduction and paired with no natural predator their numbers flourish.

Lion fish ( Pterois volitans )

The red lion fish also know by its scientific name Pterois volitans is an IAS or invasive Alien Species meaning it is not native to our region. It is native to the Indo-Pacific  region of the ocean. It arrived in Trinidad and Tobago in late 2010, and has reportedly spread to 14 countries in the Caribbean with sightings in Tobago, the Turks and Caicos Islands to St. Croix and in both Central and South America, Belize Curacao and in Venezuela. It's rapid spread in the Caribbean is due to lack of natural predators in its new habitat , which means the numbers are left to grow out of control and the native species is endangered because they don't share an evolutionary history that would have allowed them to have defensive mechanisms.

  

It is a gluttonous predator because adult lion fish are primarily fish-eaters and since they predators outside of their home range researchers state that a single lion fish residing on a coral reef can reduce the native reef fishes by 79 percent. Because lion fish feed on prey normally consumed by snappers, groupers, and other commercially important native species, their presence could negatively affect the well-being of valuable commercial and recreational fisheries.

The population of the lion fish spreads rapidly it has a life span of 16 years and reach maturity very quickly at lengths of 10cm for males and 18cm for females. Reproduction is sexual and results in 15,000 mucus encapsulated eggs. The females can breed every 4 days, with the larvae emerging after 36 hours and 2-3 days for them to become capable swimmers. 

Killer Algae (Caulerpa taxifolia)

Killer algae

Caulerpa taxifolia the Mediterranean strain also known as "killer algae" got its name because of its destructive effect on the Mediterranean coast. This algae usually grows in tropical waters and is native to the Indian ocean. It got from the Indian ocean to the Mediterranean sea in different ways.

                                       Map showing location of Mediterranean an Indian ocean    

Aquariums often collected and bred this strain of algae for display and was often accidentally dumped in the waters, it also came in the ballast water of ships coming from the Indian ocean. The first discovery of Caulerpa taxifolia covered 1 square meter of coastline and people ignored it. Over time the algae gained resistance to cold temperatures and by 2000, the algae covered over 131 square kilometers of coastline in France, Italy, Spain, Monaco, and Croatia. It is invasive because its continuous spread is causing ecological and economic harm. This strain of Caulerpa taxifolia overgrows the natural flora an fauna leading to a loss of key species. Also the blanket of algae have cause reduced fishing and tourism in many communities. It also appeared in Southern California and near Sydney Australia. The governments in California and New South Wales started eradicating the "killer algae" before it spread. Millions of dollars have been spent on treating the algae with chemicals. They also limited accidental spread by banning swimming, boating and windsurfing in infested water bodies.

Introduction To Invasive Marine Species

Invasive species are any organism ( plant,animal,fungus,bacteria ) that has negative effects on our economy, our environment, or our health. These marine aquatic plants are introduced plants that have adapted and can now grow partially submerged or submerged in water. Invasive species can also be know as nuisance species that are not indigenous and they endanger the abundance or diversity of  the native species.

There are many different types of invasive marine species such as :

 Green Crab ( Carcinus maenas )

Killer Algae ( Caulerpa taxifolia )

Sea Walnut ( Mnemiopis leidyi )

Veined Rapa Whelk ( Rapana venosa )

Zebra Mussel ( Dreissena polymorpha )

Red Lionfish ( Pterois volitans )

 Hi, my name is Kevin Lopez and my first post will be a brief introduction on myself and why I chose this topic.I'm currently a year one student of U.W.I ( University of the West Indies ) St. Augustine campus located in Trinidad and i'm  pursuing a Bsc degree in Environmental Science and Sustainable Energy.

As you can see from the header of this blog page I have chosen to post regularly on the various species of invasive marine organisms. I have chosen this because i'm interested in the marine environment as well as helping others understand that there aren't just man-made threats to the marine ecosystem but also natural ones if left unchecked.