Maui coral reefs need to be protected from human impacts 

Global Warming and Bleaching

Corals are made of single celled photosynthetic algae called zooxanthellae (Hagen, 2018). These organisms can only live in a very specific temperature and if the worldwide temperature rises beyond 2 degrees celsius, the majority of the world's corals would die (Hagen, 2018). There are several stress responses corals exhibit when trying to reduce calcification, all of these responses are detrimental to the health of a reef (Hoegh-Guldberg, 2007).

Bleaching occurs when stressed zooxanthellae, largely due to rising ocean temperatures and continued human contact, turn white and eventually expel themselves from the coral tissue (Cheal, 2008). Eventually, as the coral dies, algae begins to grow on the exposed skeletons and creates a mossy landscape (Hagen, 2018). These bleaching episodes have become progressively worse as thermal anomalies continue to worsen and lengthen (Hoegh-Guldberg, 2007). Corals can survive a bleaching episode but it leaves them with significantly slower growth and extremely vulnerable to coral disease (Hoegh-Guldberg, 2007). Between 1996 and 2012 Miami has experienced a 3 inch rise in sea level and is expected to experience another 15 inches by 2045, due to global warming (Hagen, 2018). This sea level rise is also somewhat due to the collapse of coral colonies along the Florida coast (Hagen, 2018). Floodwater is also a major issue along the coast due to detrimental hurricanes and storms that frequent the area. Corals are also vital when it comes to storm protection (Hagen, 2018). Intensified storms due to global warming could raise flood water costs by 91%, this exuberant uprise would be due to the loss of coral reefs that help combat storm surge and flooding (Hagen, 2018). The continuously changing climate may not stabilize for hundreds of years, if these ocean conditions continue, reefs will turn into rapidly eroding banks of rubble as seen in some parts of the Great Barrier Reef in Australia (Horgh-Guldberg, 2007)

Pollution

Along with global warming, pollution is extremely harmful to marine ecosystems (Hagen, 2018). Pollution can consist of multiple types, microplastics, trash, runoff, and even sewage (Pastorok, 1985). Pollution, coupled with global warming, creates an even more hazardous environment for corals as toxic substances are often enhanced in warmer waters (Pastorok, 1985). The most common response to sewage pollution around coral reefs is an increase in benthic algae and a decrease in the diversity of corals throughout a reef (Pastorok, 1985). During a case study, researchers discovered that the death rate of coral tissue was 4-5 times higher near the sewage outfall than in control areas (Pastorok, 1985). In addition to sewage, sediment runoff plays a major role in the coral health crisis. Unregulated alterations to coastal regions have also been fatal for coral reefs (Kuhlmann, 1988). The destruction of plant coverage, burning of grasslands and deforestation expose the fertile topsoil and is eventually blown into the ocean suffocating and damaging the corals (Kuhlman, 1988). Zooxanthellae use photosynthesis to create food and energy. When water gets polluted with runoff it makes the water extremely cloudy and dark, making it more difficult for zooxanthellae to produce the nourishment and strength the corals need to survive. At Hawaii’s Kaneohe Bay 880 hectares of coral was destroyed by the introduction of municipal sewage and shoreline erosion, the dead coral skeletons were covered in silt and a dark grey color (Kuhlman, 1988). The sewage site has since been moved a good distance away from the reefs and the corals started to slowly recover before they were damaged again by rising sea temperatures (Kihlman, 1988). “ Improved water quality is an identified management goal for promoting a reef's resilience to disturbance.” (Wooldridge, 2009).

Overfishing

Overfishing was seen as one of the three most significant threats to coral reefs around the world (Roberts, 1995). Overfishing can lead to major shifts in community structure for both fish and for the reefs, reduces biodiversity, and can lead to the loss of keystone species which can affect the process of a reef, and finally overfishing could lead to the loss of entire functional species groups (Roberts, 1995). The loss of predator species such as groupers, around coral reefs is largely due to overfishing in the area (Roberts, 1995). Many species are forced to switch their diets due to overfishing (Roberts, 1995). For example the triggerfish and two species of toadfish have changed their diets towards a variety of invertebrate due to the loss of the keystone species the urchin (Roberts, 1995). Trawlers fishing near the shore stir up loose sediment and mud that can remain suspended in the water for up to five years, eventually falling onto coral reefs and choking them (Kuhlman, 1988). Destructive fishing practices like these can destroy entire fish colonies and harm future generations (Kuhlman, 1988).