Unit 5 Bull Shark

 

The Carcharhinus leucas, better known as the Bull Shark, grows up to between 7-11.5 feet in length weighing between 200-500 pounds with female Bull Sharks often being larger. The average life expectancy of these creatures is between 18-27 years The top coloring of these sharks are pale to dark grey fading to a lighter grey and white down underneath. They have short, blunt snouts.  The population of this species is difficult to determine based on the extreme fluctuation but they are certainly in a vulnerable decreasing state.

The Bull Shark resides in the Wetlands, Marine Netiric, and Marine Coastal/Supratidal habitats. The tend to travel great distances ending up in freshwater rivers if given appropriate temperatures, prey, depth, and current. Female bull sharks will give birth in these freshwater rivers twice a year to about 6-8 pups. They also prefer to live near seabeds just off shore near coral sites. Bull sharks feed on fish mainly but they will also go after other species of shark, turtles, birds, and other marine mammals like dolphins. An interesting fact about bull sharks is that they the often attack and stun their prey by head-butting them.

Bull Sharks are considered a key stone species meaning if they go extinct it will devastate the ecosystem. They are also considered an apex predator. Without having natural predators like these bull sharks it will slowly collapse the ecosystem. One particular cause of the decline of bull sharks is due to human interference. They are often bycatches of fishermen. Outside of being bycatch they are sought after for their fins, oil, and meat. A second major cause of their decline is because of their habitat degradation. This degradation is from water pollution, damming, coastal development, and agriculture. The importance of keeping this species intact and well populated is firstly important because they are part of the ecosystem and shouldn't be taken out, secondly they benefit the economy when it comes to fisheries and commercial fishing, lastly, they impact habitats and are vital in maintaining a balanced order.

The United States has a current conservation plan called Atlantic Highly Migratory Species Fishery Management Plan. This program put in place regulations requiring permits, limiting permits, commercial and recreational permits, and mandatory workshops for shark dealers. On top of this, they have closed off certain coastal waters which are nurseries inhabited by pups and juveniles.

The Nature Conservancy uses GIS to actively tag and track bull sharks. They are trying to observe their migration patterns and breeding areas to get a better population estimate. Along with this it can show scientists other habitats that these sharks use and reside in.

Protecting this species of shark will take a lot of volunteering, donations, waste control, awareness, and new passed laws. To join the fight I recommend donating first. It is a quicker and easier way to make a change. If you have more time to spend, volunteering is a second way to improve the population and livelihood of this species. One key factor to preventing a species decline is to not throw trash away that can't be composted. It will end up in landfills and waterways polluting the coasts. Bring awareness to the decline of bull sharks. They can't speak for themselves and rely on us to improve their lives. Post on social media, get the message out. Finally, we want to seek help for legislators. If we can get them to properly enforce, regulate, and punish for crimes against wildlife, marine life and more, it will have a major posite effect on the world and those that can't speak for themselves.