Crown-Of-Thorns Starfish Facts You Never Knew

Crown-Of-Thorns Starfish Facts You Never Knew Crown-of-thorns starfish (Acanthaster planci)  are beautiful, prickly and devastating creatures that have caused mass destruction to some of the worlds most beautiful coral reefs. Description One of the most noticeable features of the crown-of-thorns starfish is the spines, which may be up to two inches long. These sea stars  can be from nine inches to up to three feet in diameter. They have 7 to 23 arms. Crown-of-thorns starfish have a variety of possible color combinations, with skin colors that include  brown, gray, green, or purple. Spine colors include red, yellow, blue, and brown.  Despite their stiff appearance, crown-of-thorns starfish are surprisingly agile. Crown-of-Thorns Starfish Facts Kingdom: AnimaliaPhylum: EchinodermataSubphylum: AsterozoaClass: AsteroideaSuperorder: ValvataceaOrder: ValvatidaFamily: AcanthasteridaeGenus: AcanthasterSpecies: Planci Habitat and Distribution Crown-of-thorns starfish prefer relatively undisturbed waters, found in lagoons and deep water. It is a tropical species that lives in the Indo-Pacific Region, including the Red Sea, South Pacific, Japan, and Australia. In the U.S., they are found in Hawaii. Feeding Crown-of-thorns starfish usually eat the polyps of hard, relatively fast-growing stony corals, such as staghorn corals. If food is scarce, they will eat other coral species.  They feed by extruding their stomach out of their bodies and onto the coral reef and then using  enzymes to digest the coral polyps. This process can take several hours. After the coral polyps are digested, the sea star moves off, leaving only the white coral skeleton behind. Predators of crown-of-thorns starfish (mostly of small/young starfish) include the giant triton snail, humphead Maori wrasse, starry pufferfish, and titan triggerfish. Reproduction Reproduction in crown-of-thorns starfish is sexual and occurs through external fertilization. Females and males release eggs and sperm, respectively, which are fertilized in the water column. A female can produce 60 to 65 million eggs during a breeding season. Fertilized eggs hatch into larvae, which are planktonic for two to four weeks before settling to the ocean bottom. These young sea stars feed on coralline algae for several months before switching their diet to corals. Conservation The crown-of-thorns starfish has a healthy enough population that there is no need to evaluate it for conservation. In fact, sometimes crown-of-thorns starfish populations can get so high, they devastate reefs. When crown-of-thorns starfish populations are at healthy levels, they can be good for a reef. They can keep larger, fast-growing stony corals in check, allowing small corals to grow. They also can open space for more slower-growing corals to grow and increase diversity.   However, about every 17 years, there is an outbreak of crown-of-thorns starfish. An outbreak is said to occur when there are 30 or more starfish per hectare. At this point, the starfish consume coral faster than the coral can regrow.  In the 1970s, there was a point when 1,000 starfish per hectare were observed in a section of the northern Great Barrier Reef. While it appears these outbreaks have happened cyclically for thousands of years, recent outbreaks seem to be more frequent and severe. The exact cause is unknown, but there are some theories.  One issue is runoff, which washes chemicals (for example, agricultural pesticides)  from the land into the ocean. This pumps  more nutrients into the water that causes a bloom in plankton, which in turn provides extra food for crown-of-thorns starfish larvae and causes the  population to boom.  Another cause may be overfishing, which has decreased the population of starfish predators. An example of this  is the overcollection of giant triton shells, which are prized as souvenirs.   Scientists and resource managers are seeking solutions to crown-of-thorns starfish outbreaks. One technique for coping with the starfish involves poisoning them. Individual starfish must be poisoned manually by divers, which is a time- and labor-intensive process, so it can only feasibly be conducted over small areas of a reef.  Another solution is to try to prevent outbreaks from happening or stop them from becoming so large. One way to do that is through working with agriculture to reduce pesticide use, and through practices such as integrated pest management.   Use Care When Diving When snorkeling or diving around crown-of-thorns starfish, use care. Their spines are sharp enough to create a puncture wound (even though a wet suit) and they contain a venom that can cause pain, nausea, and vomiting. Resources and Further Reading Acanthaster planci (Linnaeus, 1758). World Register of Marine Species. Becker, Joseph. Marine Envenomations: Invertebrates. Alert Diver Online, Paul Auerbach, Dan Holdings, Inc., Spring 2011. Crown-of-thorns starfish. Australian Institute of Marine Science, Australian Government, 2019. Crown of Thorns Starfish. Reef Resilience Network, The Nature Conservancy, 2018. Hoey, Jessica. Environmental Status: Crown-of-thorns starfish. Great Barrier Reef Marine Park Authority, Australian Government, August 2004. Injection culls reef-killing crown of thorns starfish. The Sydney Morning Herald, April 22, 2014.   Kayal, Mohsen, et al. Predator Crown-of-Thorns Starfish (Acanthaster planci) Outbreak, Mass Mortality of Corals, and Cascading Effects on Reef Fish and Benthic Communities. PLOS ONE, October 8, 2012. Shell, Hanna Rose. Locomotion in Water. Scinema Study Guide, CSIRO.

Anesthesia Awareness Essays - Medicine, Pain, Anesthesia

Anesthesia Awareness Essays - Medicine, Pain, Anesthesia Anesthesia Awareness Anesthesia is used during surgery to put people to sleep so that they don't feel immense pain, instead they sleep for the entire operation which makes the surgeons job quicker and more effective compared to operating on a living patient going through severe pain and probably moving the whole time making it a lot easier for the doctors to make a mistake that could be life altering. But in some cases patients who are under anesthesia are able to wake up during their operation "which doctors call anesthesia awareness." This situation is rare and refers to when patients can remember where they are and pressure or pain, that occurred to them during their surgery while they were meant to be under anesthesia. And so the patient wakes up paralysed because they are not fully asleep, and because of this they could be screaking and no one would be able to hear them, only after the operation would people become aware of what happened and know that for the duration of the surgery this patient was able to feel everything that was happening to them and had no chance of getting them to stop. Before the operation doctors tell their patients that they will be put to sleep for the duration of the surgery as it ensures that they don't feel any pain. But this is not the case and what they are actually doing is putting the person in a reversible coma so they have no memory of what went on in the operation and the pain they would have experienced. Today doctors use machines that monitor the patient's brain activity that allows them to see if the person wakes up so that they can reduce them from experiencing this extra pain, but this is not always recognised and some people still wake up and have to endure this pain.

Renewable Energy Resources Dissertation Example | Topics and Well Written Essays - 3750 words

Renewable Energy Resources - Dissertation Example The fuel could be in solid state, or in liquid or gaseous form, and the resulting energy could be electricity, heat or a combination of the two, depending upon the nature of the fuel and the energy needs. Utilisation of biomass for harnessing energy is a common trend that is growing as new methods for energy extraction are developing. In UK, the supply of biomass is limited. With the growth of the building industry, the demand of biomass energy is increasing, and hence, there is a need for an import of biomass in accordance with certain regulatory clauses. Constant effort is being made for a high quality and cost-effective import and utilization. Nevertheless, UK is the leading country in the sector of biomass consumption for the production of energy, especially for use in the building sector, in Europe. The Two-Stage Process: Harnessing the biomass energy is a two stage process. The first stage is the conversion of solar energy into chemical energy that is stored in the various fuel s used to produce biomass energy. This conversion takes place during photosynthesis. 1/10 of the solar energy incident on earth is stored as bio-energy, and out of this, 90% is stored in the wood of the trees, hence, making it the most common biofuel in the building sector. The key point here is to note that this stage removes carbon dioxide from the atmosphere, hence decreasing the amount of the greenhouse gas. No other renewable energy source has this feature to it.