The Incredible Leopard Shark

Commonly known as leopard sharks, Triakis semifasciata are an incredible species of shark.

Easily identified by the dark spots and saddles that cover their bodies, they are an absolutely beautiful sight when one swims by you.

Whether your first reaction to the thought of a shark swimming by you is positive or negative, it doesn’t much matter since leopard sharks are extremely docile, and actually a bit skittish when you get too close.  Leopard sharks in fact serve as both predator and prey in marine ecosystems.  They fall prey to larger species of shark and male sea lions, while their diet is made up mostly of squid, small fish, and crustaceans.

Now, you might think that a leopard shark swimming by you wouldn’t be a very common occurrence, but that is certainly not the case if you go swimming at La Jolla Shores Beach in San Diego, CA.  Every year, between early Summer and late Fall, hundreds of leopard sharks make the shallow waters of La Jolla Shores their home.  At any given time, you can wade out into the shallows, snorkel, or kayak and see the hundreds of leopard sharks swimming calmly below you in the clear water.

This might lead you to wonder, what are they all doing there?

That is exactly what Dr. Andy Nosal, a post-doctoral researcher at Scripps Institution of Oceanography, wondered too.  So, in 2009, Andy started researching this unique population of leopard sharks.  And in 2012, I was fortunate enough to have the opportunity to assist him in doing so.

From Andy’s research, it was discovered that 97% of the leopard sharks at La Jolla Shores are actually pregnant females.  And the main reason why they “hang out” in this very specific location is because the water is in fact a few degrees warmer here than anywhere else along the coastline.  This warmer water helps them to incubate their developing pups and make their gestation period as short as possible.

So now you might wonder, why is the water warmer there?

In La Jolla, there is a deep underwater canyon that comes close to the shore.  The depth of this canyon causes there to be decreased wave action on the shore in front of it.  And when shallow water is calm, and not being stirred up by waves, it warms in the sun, thus making it a bit warmer than areas with more wave action.

This underwater canyon not only causes the water at it’s head to be an ideal place for these leopard shark moms to incubate their pups, but it also provides an amazing food source.  At night, when the shallow waters are no longer being warmed by the sun, the leopard sharks go into the underwater canyon to feed on market squid.  The market squid are coming up from the depths to spawn, and thus provide an enormous squid buffet for the leopard sharks.

Being able to study these sharks in the field with Andy was an incredible experience.  In learning more and more about these leopard sharks, I became more and more inspired by them, and the impact that they have.

I see leopard sharks as more than just another interesting shark species.  I see them as sort of a “poster child” for all sharks.  Because they are beautiful, because they are very docile, because people can easily interact with them, they serve as a perfect gateway into changing many peoples negative perceptions and fears of sharks.  People from all over the world come to La Jolla, and often end up snorkeling or kayaking with the leopard sharks.  When a person can have a positive personal experience with a shark it is definitely a good thing.

Sharks are highly endangered throughout the world due mostly to commercial fishing practices.  The more people like sharks, the more apt they will be to want to protect and conserve sharks.

So, without even knowing it, leopard sharks are changing the world’s perception of sharks, and ultimately helping to make the world a better place for all sharks.

Introduction

Since I have just created my site, I figured it would be fitting to give it an introduction.

In the biology of life, in the experience of life, and definitely in my life, there are many uncertainties.  But one thing I am always certain of is my passion for the ocean and the organisms that inhabit it.  One quote always comes to mind when my life seems a bit more uncertain than usual:

“Definiteness of purpose is the starting point of all achievement.”  -Clement Stone

This quote reminds me that because I have this definite purpose, this drive to protect the ocean, I will be successful.  I will be able to achieve my goals of success because I have a set purpose.

The ocean is definitely not my only interest, but it is, and always will be, my definite purpose.  That is why I am: For the Ocean.

I am looking forward to creating positive impacts for the ocean through collaboration with others.

-Allison