Coral Reef Threats

photo credit: http://www.unknownworld.co/content/great-barrier-reef/

Coral reefs are a very important habitat in marine ecology and support thousands of organisms by creating homes, protection, and more. Coral reefs support increased biodiversity in our ocean. Many coral reefs have collapsed to a point of no return. Coral reefs have an extended number of factors that threaten its success. For my presentation, I will be discussing these threats and what is going on in research and politically to study and change the affects of them on coral reefs. 

Some of the threats on coral reefs have to do with ocean acidification, predators such as the Crown of Thorns starfish, pollution, over-fishing, invasive species, oil, gas, mineral exploration and extraction, and more. There is a long list of threats on coral reefs which makes it even harder to protect them because they can get targeted in multiple ways. Long term solutions are very tough to find for some of these threats. 

One reason why it is difficult to find solutions to coral reef threats are because of the continual change in the ecosystem due to acidification. For example, while trying to take care of an invasive species, we may not be able to help organisms who are also being affected by the pH changes in the water. 

I will be discussing as many threats as I can and what solutions are being proposed, are being used, and what we can do to help with this effort. Coral reefs bring a lot of good to marine life and also to our economy through fisheries and tourism. I will also touch on policies that may be in our near political future on CO2 emission and clean energy.

http://proxy.ashland.edu:2318/ehost/detail/detail?vid=17&sid=6330e763-5339-41e4-bf3d-ab624a4b152f%40sessionmgr4005&hid=4214&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#AN=103381605&db=a9h

http://proxy.ashland.edu:2318/ehost/detail/detail?vid=18&sid=6330e763-5339-41e4-bf3d-ab624a4b152f%40sessionmgr4005&hid=4214&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#AN=98773519&db=a9h

http://www.divetioman.com/download/COT%20Best%20Practice%20for%20Clean%20ups.pdf

http://onlinelibrary.wiley.com/doi/10.1111/j.1541-1338.2007.00265.x/full

http://coralreef.noaa.gov/threats/

Seahorse Reproduction

      A few weeks ago, I made a post about reproductive strategies that are found and utilized within different species of marine seahorses. As abstract and weird as this sounds, it was actually quite fascinating to learn about. The average person probably has no idea how seahorses mate, let alone why it is unique. The male is the one who actually becomes 'pregnant.'
      Male and female seahorses will court for several days, and will take part in a dancing ritual. They will swim side by side at the same pace, so as to display that they are in sync with each other. The female will deposit the eggs into a pouch on the male's stomach region, where the eggs will brood for up to forty five days, or until the young emerge fully developed. This is why the male is considered to be the 'pregnant' one.
      While the eggs are still inside the male, the female will come and check on him almost daily. The males will become very aggressive to try and protect the young inside him, and will also puff out their stomach region, trying to increase their size to ward off potential predators and to also help protect the young. They will then be released into the water, and the males will leave them alone. At this point, the young are on their own to find food and protect themselves.
      Even though there are high numbers of young that are released by the male at the end of the brooding period, the survival rate is less than one percent, from the time they are released until the time when they reach sexual maturity. In this presentation, I would like to address all these points, as well as what happens physically within the body of the male seahorse itself.

http://onlinelibrary.wiley.com/doi/10.1002/bies.20626/epdf

http://link.springer.com/article/10.1023/A:1013894804529

http://onlinelibrary.wiley.com/doi/10.1111/j.0022-1112.2004.00429.x/full

Tardigrades

Tardigrades more commonly known as water bears are a phylum of animals known to survive the most extreme conditions on earth, even surviving the environment of outer space. For my presentation I plan to talk about what allows for them to survive is such extreme and varying habitats such as their DNA, physical capabilities, their age of existence and how they have evolved, how studying these species can help humans, and better map the history of evolution. I hope for others to take away a better knowledge of a tardigrade as well as fully understanding the amazement of this species diversity.

http://tardigrades.bio.unc.edu/tardigrades/

http://uncnews.unc.edu/2015/11/23/a-huge-chunk-of-a-tardigrades-genome-comes-from-foreign-dna/

http://icb.oxfordjournals.org/content/42/3/652.full

The Ocean's Predators 

  I posted a discussion post a couple of weeks ago about two of the major predators of the ocean, killer whales and sharks. The article discussed how killer whales have been known to prey on sharks. This post led me to the idea of researching the ocean's toughest marine predators and the animals they prey on. These predators include killer whales, sharks, polar bears, and seals. I think it's interesting that some of these predators actually prey on each other. 

      I would like to talk about the different parts of the ocean both the predators and their prey inhabit along with the predators' hunting strategies. For example, I found that great white sharks can actually detect movement from as far away as 820 feet. They also have a very keen sense of smell. Another interesting fact is that although polar bears are land mammals, they spend a lot of time in the ocean and are incredibly strong swimmers. 

       Another topic I stumbled upon during research is about grazers and predators and how they benefit both terrestrial and marine ecosystems. The role that these predators play is actually very important in the survival of the ecosystem. I would discuss the trophic cascade and how when the keystone species is removed, it causes dramatic changes in the ecosystem. One example can be seen when sea otters are removed from an area, the sea urchins in that area overpopulate. The sea urchins graze on benthic algae in these environments, which disrupts the food web by leaving little food for other organisms. 

       

https://sites.psu.edu/siowfa15/2015/10/22/killer-whales-the-apex-predator-of-the-ocean/

References: 

https://www.eaglewingtours.com/top-of-the-food-chain-5-deadly-marine-predators

http://animals.mom.me/top-animal-ocean-predators-3061.html

http://marinebio.org/oceans/grazers-predators/

Deep Sea Adaptations

            The creative adaptations of organisms that live in the deep sea really caught my attention when we covered the deep sea in class.  When I found myself talking to my sister on the phone about the wavelength of red light and receptors to view this color, I realized that I had a solid presentation topic.

            I want to present about the adaptations and strategies for both defense and predation that deep sea creatures utilize.  The most obvious adaptation is bioluminescence, so I will talk about how this works with the cephalopod Vampyroteuthis infernalis as a specific example.

            Another adaptation is structural modifications.  The gastropod Crysomallon squamiferum is a fascinating example, as they have developed an intricate layer of iron-plated armor for protection in this environment.  Transparency as in the Teuthowenia pellucida squid, chameleon behaviors such as in Sepia officinalis cuttlefish, and red perception like Malacosteus niger dragonfish aid in avoiding predation.  Muscle consistency and immunity may also be included.

            Lastly, behavioral alterations in reproduction and feeding will be discussed.  Some sponges are carnivores at these depths, and parasitic reproduction is a technique unique to angler fish in the deep ocean as far as we currently know.

            Throughout the presentation, I plan to mention details about how these organisms have been studied.  As the presentation nears, I will decide which adaptation and species to select for a more in-depth focus.

Sources:
Deep Ocean
Bioluminescent cephalopod
Carnivorous sponges
Iron plating
Cuttlefish
Dragonfish
Angler fish

Whale Fall Ecosystems

When whales die and sink to the bottom, their carcass, called a whale fall, provides a concentrated food source and environment for organisms of the deep sea.  First, scavengers will consume the outer layer of tissue and detritus provides the surrounding sediment with nutrients for a year or more.  The skeleton, however, can support communities of organisms for decades.  It can serve as a hard substrate for invertebrate colonization while microbes can live off of the energy released by chemical reactions.  In all, these whale fall ecosystems can form an all new food web in the deep sea.

The study that I used for my blog post on the sperm whale fall ecosystems proved that over a course of three years (2003-2005), a plethora of species called the dead whale home.  The species mentioned in the paper were those of mollusks, polychaetes and crustaceans.  The amounts of each were documented in the paper with mollusks being the most abundant.  Epifaunal species were collected using a suction sampler while infaunal were collected using a scoop sampler.  One idea that I would like to research further is that of the shell sizes of the mollusks.  The paper mentions that one species’ shell size started large and slowly decreased while the other species’ shell size demonstrated the opposite effect.  The paper did not mention why this occurred.

An interesting idea that I will be researching is that of shallow water falls versus deep sea falls.  One paper that I have found discusses how twenty five deceased whales and the associated fauna found with them indicate the presence of a shallow water whale fall community.  In fact, the study shows that shallow water and deep sea falls differ from one another because taphonomic pathways (what happens to animals when they die and decompose) vary more on the shelf.  Therefore, shallow water whale carcasses may not go through the same pathways as those of the deep sea.

I would also like to discuss in my presentation what sorts of organisms are able to utilize the whale carcass.  I have mentioned mollusks, polychaetes and crustaceans, which do seem to be the majority of the organisms that thrive in the ecosystem.   Studies have been done to identify kinds of microbes that thrive in this habitat and how their presence is proof the sulfide-based ecosystem that the whale carcasses provide.  Moreover, new species of polychaete worms have been discovered inside of whale bones.  An example is Capitella iatapiuna , which was just discovered in February of this year.  I have come across several papers stating that new species have been discovered thanks to these whale falls.  Furthermore, I have found plenty more information regarding the ecosystems, but I have not been able to read them all.  The papers that are listed are only just a few of the studies that I have come across.

Web sites:

http://oceanservice.noaa.gov/facts/whale-fall.html

Articles:

http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0485.2007.00150.x/full

http://onlinelibrary.wiley.com/doi/10.1111/let.12054/full

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0011808 (symbiosis in the two species of mussel shells.  May provide why shell sizes differ)

http://www.sciencedirect.com/science/article/pii/S0031018211005815

http://www.sciencedirect.com/science/article/pii/S0967063715300716

Shark Migration Patterns

Sharks are apex predators in the marine ecosystem and they regulate the populations of the species below their food chain.  There are 465 known species of sharks. Sharks have skeleton that is made out of cartilage, which is a tissue that is lighter than bone. They have five to seven gills and multiple rows of teeth that continue to grow all the time. Little is known about the shark migration patterns Knowledge of the habitat and migration pattern of large sharks are important because they can assess the effectiveness of large predator Marine Protected Areas (MPAs), know the vulnerability to fisheries and environment, and have control over shark and human interactions.

In a recent study 18 adult bull sharks 195-283 cm in length were tagged and tracked from 10-22 months. It was found that 16 of the sharks showed temporally and spatially variable residency patterns combined with migration events. Ten sharks had a coastal migration with 8 of them returning to the study site.  During the migration the sharks moved at a rate of 2-59 km.d-1 and traveled distances between 450-3760 km. In spring and winter is when the sharks were found migrating in lower latitudes. There was found to be a significant negative correlation between residencies and mean monthly sea temperature at the study site. This showed that seasonal change is major factor in migration patterns and directions. Future research that could occur would to be to find out if reproductive and foraging activity could influence the migration patterns.

In another study one of the top three sharks; the tiger shark, migration patterns were studied.  There were 33 tiger sharks tagged and tracked long Australia and the Coral Sea. Satellite tags were used to study habitat use and movement among habitats across the Coral Sea. A few sharks showed one-year residency in Chesterfield and along the Great Barrier Reef. In coastal barrier reefs, tiger sharks were short lived and each one displayed a unique pattern of swimming. From 2009-20013 14 tiger sharks had wide ranging along the Coral Sea with eight shark moving back into “normal movement”. They studied concluded that the islands along chesterfield were an important habitat for the tiger sharks. There was no explanation about why there was wide ranging along the Coral Sea. There also needs to be future research on why the Marine Protected Areas (MPA) are popular for tiger sharks. The MPAs only provide brief protection to the sharks from other larger sharks. The amount of food present along the reefs could play a factor.

A graduate student, Tellman, studied the migration patterns of the blacktip shark and results were found to be like clockwork. Every winter in the Atlantic coast of Florida thousands of blacktip sharks are found. Tellman monitored the shark migration from a small airplane along the Palm Beach Coast for three winters. There was winter where she photographed 12,000 blacktip sharks during a single flight.  Each year it was found that the blacktips swim towards bays and estuaries in the Southeastern coast to mate and give birth. The juveniles will reach maturity in shallow nursery grounds away from the adults. The blacktips were found to swim in ocean temperatures from 22 to 24 degrees C. This has been slowly changing due to climate change. As the ocean heats up the warmer waters moves to higher latitudes causing the sharks to change their migration patterns.  This can cause some negative affects such as beach closures and more shark attacks. Last year the black tip migration lined up with spring break causing all the spring break travelers to be kicked off of the beach. Also the black tips were blamed for 20 percent of the unprovoked shark attacks in Florida according to the International Shark Attack File maintained by the Florida Museum of Natural History. Future research could be done to see if climate change is really having an effect on the migration patterns of the blacktips.

http://www.defenders.org/sharks/basic-facts

Daly, R., Smale, M. J., Cowley, P. D., & Froneman, P. W. (2014). Residency Patterns and Migration Dynamics of Adult Bull Sharks (Carcharhinus leucas) on the East Coast of Southern Africa. Plos ONE, 9(10), 1-11. doi:10.1371/journal.pone.0109357

Lipske, M. (2014). Shark-Swarming Season. National Wildlife (World Edition), 52(2), 1.

Werry, J. M., Planes, S., Berumen, M. L., Lee, K. A., Braun, C. D., & Clua, E. (2014). Reef-Fidelity and Migration of Tiger Sharks, Galeocerdo cuvier, across the Coral Sea. Plos ONE, 9(1), 1-18. doi:10.1371/journal.pone.0083249