STEM
STEM
more significant than overfishing, including solar activity, lunar nodal cycles, and major changes in marine food webs. Jellyfish can potentially pose as early warning indicators for global oscillations including El Nino and understanding the catalysts in jellyfish population change can help to minimize destruction caused by blooms in the future. The increased number of jellyfish in our oceans is another reminder of the impacts of ocean acidification caused by anthropogenic activities. Moreover, jellyfish are not the only non-native species heading to the UK because of warmer seas - the National Geographic predict Hammerhead, Sand Tiger and Blacktip sharks will all be inhabiting UK waters within the next 30 years. Climate change is changing the distribution of several marine species, having catastrophic effects on general oceanic biodiversity and although jellyfish are proving resilient to such changes, it is important to consider that other vital species may not be so durable.
Oceanic oxygen levels have diminished by
2 %
in the last 50 years.
the company over £1 million. Tourism is another industry suffering due to jellyfish with many beaches in Spain treating over 400 stings in a day, putting tourists off visiting the coast which will have negative economic impacts in such areas, particularly those heavily reliant on the industry. However, there are some benefits. Jellyfish act as excellent environmental indicators with the occurrence of jellyfish blooms being a signifier of changes in oceanic conditions including rising temperatures and pollution. Many scientists are now studying such incidents to gain insights into marine environments and begin to better understand the effects of climate change on the ocean. Jellyfish are essential to marine ecosystems with complex roles as both predator and prey, allowing them to help maintain balance within food webs. The increased populations of jellyfish around the UK have also had a knock-on effect on other species, causing a surge in leatherback sea turtle sightings around the coastline. The fluctuations in jellyfish populations should trigger a search for the drivers of such vast changes on both a regional and global scale, as the larger variations in population could indicate something
global phenomenon; fishing has hugely reduced the jellyfish’s natural predators including tuna and swordfish, allowing populations to boom in heavily fished areas. Research has also shown that warming temperatures enhance the production, feeding and growth rates of jellyfish, once again giving the creatures an advantage against more vulnerable competitors in marine food webs. Not only is this bad news to avid beachgoers, but destruction has been evident in more areas than one might expect. In 2011, the Torness nuclear power plant in Scotland had to be shut down as jellyfish started blocking the cooling filters, posing a potential threat to safety at the plant as well as reducing productivity. Two years later, this issue occurred again in Sweden’s Oskarshamn nuclear power plant, containing the world’s largest boiling water reactor; filters prevented the jellyfish from entering the reactor, but the plant had to be shut down. Many other human activities are being disrupted by the increased abundance of jellyfish from salmon farming to sea-bed diamond mining. 2007 saw a bloom of jellyfish clearing 100,000 salmon in Northern Ireland’s only salmon farm, costing
The increasing abundance of jellyfish, noticeable on the UK coastline, is a prominent indicator of climate change and the way that it is affecting our oceans. Due to absorbing 22 million tonnes of carbon dioxide daily, the pH of the ocean is being reduced, acidifying the sea due to the mixing of carbon dioxide with water molecules, forming carbonic acid. As demonstrated by coral bleaching, most forms of life are extremely sensitive to pH levels, but jellyfish do not seem to be suffering under these drastically changing conditions. In fact, research has shown that as the pH drops, the population of jellyfish rises. This is not due to acidic waters being preferable for jellyfish but instead due to a slight resilience to lower pHs that other species cannot survive in. As the ocean becomes more acidic, the jellyfish’s competitors are killed off and their prey becomes less healthy and therefore more vulnerable, making consumption far easier. Oceanic oxygen levels have also diminished by 2% in the last 50 years. Once again, only jellyfish appear to have a resilience to these changes, allowing them to benefit from the reduction in predation and weaker prey. Overfishing is another big factor contributing to this
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