Thursday, September 19, 2013

About the shark, what is wrong, and how we can help

DISCLAIMER: Due to the fact that not much is known about this species, some of these pictures may not be a smooth back angel shark.


The angel shark, or commonly known as a monkfish, was first recorded in 1758 by Carl Linnaeus; at the time he had no idea that there are at least 10 species of angel sharks. Once found in many tropical and cold regions, its populations have been devastated and are considered extremely rare in many places. Being bottom feeders they are not seen very often, which causes a difficulty when trying to gain information about these sharks. The smooth back angel shark was considered endangered in 2006 and was quickly ungraded to critically endangered in 2007. 


This is what a smooth back angel shark looks like from the top and side. Broad, flat, wing-like fins on the sides gives it the name angel shark. Their flat body gives them the ability to burrow into the sand and disappear, being a prime predator. Growing up to 7 feet long gives them an advantage on the smaller fish. Using a bland camouflage coloring, these sharks are able to ambush fish, arthropods, and crustaceans.


This is a picture of the angel sharks habitat that it thrives in. Large kelp are attractive to many fish for protection, as well as the smooth back angel shark. Fishing and trawling has and is destroying these kelp forests which in turn takes away their habitat. Without a place to hunt and protection for their young, this species struggles with existence.


Though they may not seem very important,they are an integral part of the underwater ecosystem, feeding on smaller prey species and being one of the few predators at the ocean floor. They have a very specialized lifestyle, being bottom dwellers, and fishing has disrupted this. Smooth back angel sharks are disappearing fast; too fast. Scientists still haven't discovered what their lifespan is yet. We need to learn more information about these sharks in order to help them further.


This video captures the ambush asset of the smooth back angel sharks abilities underwater. They are amazing predators and very important to keeping fish populations under control. There are many types of smaller fish within the angel sharks diet; horse mackerel, argentines, goatfish, flatfish, and codlets. Also octopus, squid, mud shrimp, and crabs are prey to this shark. Many of these are fished by commercial vessels, which creates a problem of the angel shark being caught too.


This unfortunately happens, and many times the shark is dead before they are able to throw it back in. Trawl lines, bycatch, and bottom lines are the biggest threats to the smooth back angel shark. The Pacific angel shark was fished commercially in California, which destroyed the populations. Soon after they stopped all fishing of it and their populations went back to normal. In the areas where the smooth back angel shark is found, some artisanal gillnet fisheries will also catch the shark for leather, oils, and meat. Near the UK, there are still some vessel doing shark finning, which the angel shark is susceptible to.


Over the past 50 years, this shark has been declared extinct in the North Sea, the northern Mediterranean  and on the western coast of Africa. Near Morocco and Mauritania there was a 95% decrease in all angel shark species once commonly found there over an 8 year span. This is a huge problem for the smooth back angel shark, their species is becoming extinct in its native areas so quickly that we are unsure where their current range is.


The main problem for the smooth back angel shark is human impact by fishing, but that is not the only thing. Reproduction of this species is ovoviviparous, which means that while in their mother they depend on a yolk for nourishment, but they go through live birth.


Though this exact species of angel shark is unknown, it is a perfect way to see how they are born. Being born like this means that they fend for themselves after birth. As small as the are when born, other predators see them as easy prey. Most angel sharks give birth to litters of 3-8 young between February and April. It is still unknown when they reach their age of reproduction, maturity, and gestation period.


This is a baby angel shark born in a aquarium, and it is barely the size of this diver's hand. It's only protection is a camouflage coloring and very small, sharp teeth. The chances of it surviving to maturity are low, but there is a chance for them. Zoos and aquariums around the world have different species of angel sharks, but it is very difficult to tell them apart. This is one of the other problems with angel sharks, fishermen will catch them sometimes and not be able to tell apart different species. Thankfully, the baby in the picture above is most likely a smooth back angel shark.


This picture shows one of the few protected areas that smooth back angel sharks and other species of angel shark are found. These marine reserves give them a chance at repopulating their once native range. There is not a direct law against fishing for the angel sharks here, so it may go on illegally. Populations here may be so small that they do not have a chance at even reproducing.


In the UK, there is currently a law against targeting  injuring, or killing a smooth back angel shark within 6 nautical miles of the coast. Non-governmental and governmental agencies all recognized that there was a huge problem going on and they finally acted on it. Due to loopholes in EU Shark Finning Ban, some vessels were still able to fin the sharks, which put these angel sharks at high risk. The group responsible for causing this law to exist is the Shark Alliance. This group is dedicated to protecting sharks all over the UK in a non-governmental organization. They have done amazing work to protect many shark species.


Though they are doing great work for sharks, there is still a lot more that needs to be done. This group does not know anything about the number of angel sharks left on the coast. In other words, there could be no angel sharks left near the UK, and fewer than 100 left in the world. We would never know if this is true or not. Everything we know about this species is either from finding a single specimem, fishermen catching them in nets, or guess work based on a different angel shark species. 

How we can help them.

Though there are not many ways to directly help the smooth back angel shark, giving to a local aquarium that houses any species of angel shark is a big start. Many aquariums have non-profit companies and use any profits towards conservation services. Aquariums in the United Kingdom are running an angel shark breeding program which has been successful. The photo of the diver with the angel shark is one. Many not-for-profit organizations are dedicated to saving all species of sharks, and every shark saved is a great accomplishment. All of the groups listed below are helping to discover loopholes in the EU shark finning ban, which is very much related to smooth back angel shark. 

(The one as seen on TV)

Save the smooth back angel shark for the health of the ecosystems, and for its unique beauty and presence. These sharks are going extinct because of human impacts and actions, so we have to fix our actions and act, before another species is lost forever.


Squatina oculata

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