Posts Tagged ‘sharks’

Shark U Week: Know Your Sharks

Friday, August 9th, 2013

How well do you know your sharks? Odds are most people only know the sharks that have been portrayed as vicious killers in Hollywood thrillers, such as the mighty great white shark in the 1975 blockbuster hit “JAWS.” But the truth is there are over 400 different types of sharks in our oceans and aquariums all over the world and, despite all the horror stories, sharks do not eat people.

Sharks come in all sizes from the massive whale shark, reaching lengths of 30 feet, to the dwarf lanternfish that’s less than 10 inches. Being able to tell the hammerhead from the nurse shark is quite easy, but others can be difficult. Can you spot the difference between a leopard shark and tiger shark?

How can you tell one from the other?

IT’S ALL IN THE BITE:

IMG_5603Sharks’ teeth are adapted for what they eat. Sharks like the great white and tiger shark have triangular teeth with jagged edges. This keeps hold of larger fish and animals, tear chunks of meat or slice through a turtle’s shell. A sand tiger’s teeth, on the other hand, are long and narrow which make them look frightening, but in fact these types of sharks are not very aggressive. The shape of their teeth is ideal for grabbing a hold of prey. However, the whale shark has very small teeth and it’s not used for biting because they simply filter their food.

SHARK MARKS:

IMG_5627Coloration and patterns play an important role in identifying a shark. Their special marks allow them to camouflage perfectly into their environment. Mako sharks, for example, inhabit tropical and offshore water and are normally a bluish color. On the other hand, the nurse shark has a tan pigmentation ideal for hiding on the ocean’s floor. Tiger sharks can be identified by their stripes and leopard sharks for their spots.

LOCATION, LOCATION, LOCATION!

Know the sharks that lurk in the water. Sharks can be found all over the world from the warm waters of the Caribbean to the freezing temperatures of the arctic. The Gulf of Mexico alone houses more than 50 different species of sharks including, on the rare occasions, the great white shark. The bull shark and blacktip shark are quite common off the shores of Galveston while the Caribbean reef shark is obviously in the Caribbean.

 

Shark U Week: Sharks 101 Part 2

Thursday, August 8th, 2013

Shark U Week: Sharks 101 Part 1

Tuesday, August 6th, 2013

Shark U Week: The Secret World of Shark Finning

Monday, August 5th, 2013

By Greg Whittaker
Moody Gardens Animal Husbandry Manager 

In early 1999 I found myself in Taiji, Japan working on a marine mammal acquisition for the Beijing Aquarium.  The conservation ethics surrounding “The Cove” are another story deserving its own chapter at another time. While we were working at a Dolphin encounter resort on the outskirts of Taiji, we were staying in a fishing community just to the north called Katsuura.  Every day we drove past the waterfront in Katsuura through the bustle of activity around the fishing markets.  On one of my few days off, I visited the market to see what was being caught and auctioned.  The sheer number of top level predator fishes that were laid out in organized stacks in the football-field-sized warehouse space was amazing.  Tuna, mackerel, billfish and ocean sunfish made up the bulk of the daily catch.  There were also several piles of shark fins stacked 4’ high and spreading over perhaps a 12’ diameter area.  I couldn’t locate any shark bodies in the entire market area, just three or four large heaps of fins.

The shark finning problem had not been as apparent back then, but the lack of carcasses hit me as a tremendous resource waste in a culture that had up to that point appeared contrary to such practice.  We were scrutinized by neighborhood mama-sans for not removing all recyclable materials from our trash.  The few occasions where we ventured through the Taiji waterfront were an incredible lesson in efficiency where the harvested dolphins and whales were carved up for consumption with nearly no waste evident.  How could a people so intimately linked with existing on the natural resources of the sea be so wasteful of their harvest?  It wasn’t until I later learned of the international demand for shark fin soup, that I fully understood what I had encountered in Japan.

Over the course of 3 months, we passed the Katsuura waterfront market daily and a subliminal counter was clicking in my mind.  Six days a week, thousands of tuna, dozens of billfish and those uncountable piles of shark fins every day, rain or shine.  Between the seemingly unscrupulous harvest of entire pods of cetaceans in Taiji and the daily take of finfish in Katsuura, the efficiency of removing these natural resources was mind numbing, and the ocean’s ability to sustain this level of take was something I struggled to understand.

What is Shark Finning?

On one spring morning shortly before our departure from Japan with our dolphins and whales, we had some free time to explore the area.  We happened upon a complex of houses a few streets behind our own that was a processing facility for shark fins.  The entire area was perhaps an acre with a large open space between 3 houses.  The central yard space was filled with 3 tiered clotheslines with two horizontal racks beneath them.  Shark fins were hung on the lines like laundry and all of the horizontal shelving was filled with trays containing drying fins 4 or 5 deep.  There were lines strung between the houses, both first and second stories with similar triangular, gray fins hanging in the sun to dry.  The entire roof surfaces of all 3 houses, including the shorter sheds attached to them, were completely covered with shark fins of all sizes, looking like roof tiles.  There were 2 vans parked in the driveway that were completely stuffed with baskets of dried shark fins inside, and completely covered with drying shark fins on top.  My Australian buddy Wayne and I took pictures and tried to count just a small portion of what we were seeing, but couldn’t even begin to estimate how many sharks were represented by what we saw.  There were likely 10,000 fins drying at that one complex the day we happened upon it.  The staggering thing is that we went back a few days later and there was a completely new batch of fins being processed.

Get schooled about SHARKS at #SharkUWeek at Moody Gardens!

 

Shark U Week: Here’s Your Syllabus

Thursday, August 1st, 2013

Take a bite out of summer during Shark University Week at Moody Gardens Aug. 4 through Aug. 10. Moody Gardens is a proud sponsor of Discovery Channel’s Shark Week.

Shark U Week

 

Sharks: A more diverse species than most realize

Wednesday, August 15th, 2012

By Greg Whittaker

Working in the zoo and aquarium industry offers a lot of perks. That’s because we get to work with some of the coolest animals in the world.

As I was walking through the exhibits looking at what our guests see, I started counting the species of sharks and rays we house at Moody Gardens® and the diversity they represent in habitat, diet, behavior and natural history. From the secretive swell sharks and wobbegongs to the large active brown sharks and sand tigers, we have 22 species from Galveston’s local waters to Australian reefs from the other side of the world. We have three species of stingrays that are found in the Amazon River basin and are so completely adapted to living in freshwater that they can’t exist in the brackish delta.

One of the questions we answer while walking through the public galleries is, “Where are the sharks?” Over time we’ve come to realize that most guests are referring to the Caribbean exhibit and the large, easily recognizable species.

You might be surprised to hear that four out of these five are relatively common species in the waters just off Galveston. If they truly were the bloodthirsty human predators they’re portrayed to be, we surely would be losing more tourists and fishermen to the sharky menace.Looking at the tremendous diversity of sharks, rays, skates, guitarfish, sawsharks and sawfish all collectively grouped together as cartilaginous fishes, there are over 1,200 different species. The sharks that gain all of the attention are the ones that grab the headlines in “attacks” on humans, and the five that are generally agreed upon as the top “maneaters” are – great hammerhead, lemon, bull, tiger and white sharks.

In reality, the vast majority of the 100 incidents that are reported worldwide annually are cases of mistaken identity with small, non-dangerous species. Contrast those statistics with the estimated 350 to 500 million sharks that are removed from the world’s oceans every year. Many of those are reproductively mature adults of species that are in perilous population declines and in some cases, they have their fins cut off and are dumped back into the water to die.

Even if you don’t particularly like sharks, you have to see how wasteful shark finning is.

Back to the amazing diversity – whale sharks are the largest fish with a maximum length of 45 feet and weighing as much as 36 tons. Along with basking sharks and megamouth sharks as the most menacing-sized sharks, they all filter feed on plankton and small fish. On the opposite end of the spectrum, the tiny cigar shark reaches a maximum size of only about eight inches long.

The biggest ray species is the manta which can have wing tips that measure almost 24 feet wide and weigh almost 3,000 pounds. Electric rays generate powerful electric currents that protect them from predators and assist in navigating dark murky water and capturing prey. Between sharks and rays is an assortment of species that have aspects of their appearance that match both – a  generally flattened body with elongated tails. These include angel sharks, guitarfish, sawsharks and sawfish.

Sharks can fill ecological niches from scavengers to apex predators and have reproductive strategies that include eggs deposited within the reef to complex internal egg incubation, internal hatching and internal cannibalism of siblings.

From this rambling account, you hopefully have gained enough perspective to realize that “sharks” cannot be painted with a simple broad brush stroke. They generally all came from ancient ancestors hundreds of millions of years ago. They fill every available niche and are remarkably adaptable to environmental changes and pressures placed on them.

For every species we can provide care for in the captive aquarium, there are dozens of other species that we simply don’t know enough about.  It’s a safe wager that there are untold numbers of species out there that we haven’t even discovered yet.

Sharks: Fact vs. Fiction

Monday, July 18th, 2011


A recent string of shark sightings along the Texas Gulf Coast has sparked a flurry of media interest and has beach-goers questioning their safety in the salty waters. According to recent reports, two large sharks were caught from the shorelines at Crystal Beach and Matagorda Bay and a college student was bitten at Surfside Beach, adding to the animosity between man and fish that Steven Spielberg helped permeate our culture nearly four decades ago.

While the image of massive aquatic beasts breaking the surface to swallow anything in sight has been burned into our collective consciousness via Jaws or the Discovery Channel’s Shark Week, several experts, including those at Moody Gardens, say that sharks are misunderstood creatures and it’s important that humans learn to respect them and know how to safely share the ocean with them.

For any who are apprehensive about visiting Galveston and going to the beach because of what may be swimming beside them the water, here’s a breakdown of shark fact and fiction to help shed some light on whether or not their reputation is deserved.

FICTION: Increased sightings of sharks in the Texas Gulf Coast means I’m more likely to get bitten if I go swimming.

FACT: Instances of sharks attacking humans are extremely, extremely rare. According to Roy Drinnen, Moody Gardens’ assistant curator of fishes, while there are numerous sharks that make their home in the waters off Galveston Island, there have only been approximately 11 shark bites reported in the Galveston Bay area in the last 100 years.

“There are sharks out there. That’s their home. We basically are visitors when we go swimming. We have to expect them to be out there,” Drinnen said. “You have a better chance being struck by lightning or killed by a group of bees.”

FICTION: Sharks are a bigger threat to humans than humans are to sharks.

FACT: Humans are a huge threat to sharks, as overfishing is the biggest threat to their existence. A soup made from shark fins is a delicacy in many countries. Sharks are routinely caught and thrown back into the ocean to die after their fins are chopped off in a process called “finning.” Finning is now prohibited in the United States.

FICTION: There’s nothing you can do to reduce your chances of being attacked by a shark.

FACT: Swimmers can take numerous precautions to reduce their chances of being mistaken for prey by a shark. A few tips include:

  • Avoid swimming at dawn and dusk (sharks’ typical feeding time)
  • Avoid wearing any shiny, flashy clothing or jewelry that a shark can mistake for a fish in the Gulf’s murky waters
  • Leave the water if you are bleeding in any way, as sharks are attracted to the smell of blood.

Overall, sharks are beautiful animals that deserve respect more than fear. While sharks are plentiful in the Gulf of Mexico with approximately 15 species inhabiting the waters around Galveston, attacks are few and far between.

To learn more about sharks, visit the Sharks: In Depth exhibit, currently in the Aquarium Pyramid at Moody Gardens®.