Cora Blu "A Little Underwater Did You Know"

Although tiger sharks are native to the tropical waters of Pacific Ocean, in my world they live in all waters. As the largest member of the carcharhinidae family of sharks, which include other species like the bull shark (head of security in “Dagger”) and blue shark, they are majestic in my opinion.

One of the interesting facts concerning the tiger shark is their propensity to venture into shallow waters in search of prey—a behavior not common in fish of this size. (10-14 ft in length)

Tiger sharks are fish, not mammals, hence the gills. 

Reproduction: Female tiger sharks become fertile about every three years, they carry 80-100 fertilized eggs. Only one or two of these eggs survive, resulting in a live birth about 14 months later. 

(Fortunately, I’ve tweaked that a touch in “Dagger”. To be pregnant for fourteen months is a bad look, doesn’t matter how much pregnancy glow you have.)

What happens if you turn a shark on its back—if you get that close? Tonic immobility.

This is a behavior, which occurs in sharks when a diver turns them onto their backs in the water. For some reason, turning a shark onto its back causes the shark to go into an almost trance like state. As soon as a shark is turned right-side-up again it swims away acting as if nothing had happened. Scientist have not yet discovered what causes tonic immobility in sharks, but they have theorized that being turned over somehow causes an imbalance which puts the shark into this immobilized state.

(In California a pod of killer whales have somehow figured this out. By ramming the shark in the side, flipping it over, it’s immobilized long enough for the killer whale to then hold it suspended upside down until the shark slowly suffocates and dies. Seemingly they only eat the sharks liver.) 

  • Hearing:
    1. Sharks have only an inner ear, which consists of three chambers and an ear stone called an otolith. A shark’s inner ear detects sound, acceleration, and gravity.
    2. Sharks use sound to locate food.
      1. Sound is often the first sense a shark relies on to detect prey.
      2. Under water, sound travels faster and farther than on land.

Sharks are attracted to low frequency pulsed sounds, similar to those wounded or ill prey would emit. Most attractive sounds are in the frequency of 25 to 100 Hz. Some sharks are attracted to sound sources from distances as great as 820 feet.

(These proved helpful in creating my characters, pretty cool when you can feel someone at the front door when you are in the shower)

  • Lateral Lines:
    1. The lateral line system is a series of mucus-filled canals just below the skin of the head and along the sides of the body. The canal is open to the surrounding water through tiny pores.
    2. Like the ear, the lateral line senses low-frequency vibrations. It functions mainly in distance perception and detecting low-frequency vibrations and directional water flow. Water movement created by turbulence, currents, or vibrations displaces the canal mucus. The lateral lines in the shark transforms underwater sound or mechanical disturbance into nerve impulses.


  1. Sharks have good eyesight and they have color vision.
  2. Shark eyes have a large, spherical lens, a cornea, a retina, an iris, and a pupil. They even have good vision in dim light.
  3. Sharks, like cats who also see well in dim light, have a mirror-like layer in the back of the eye, the tapetum lucidum. This layer doubles the intensity of incoming light, enhancing light sensitivity.
  4. Unlike other fish, shark’s pupils can dilate and contract to control the amount of incoming light. The retina has a greater proportion of light intensity sensors (rods), than color sensors (cones), so sharks are very sensitive to small differences in light intensity (dark versus light).
  5. Some sharks have a nictitating membrane, a type of second eyelid, that protects the eye during hunting.
  6. Sharks that live deeper in the oceans usually have larger eyes than those that live nearer the surface.
  7. A shark can see at a distance of up to 50 feet.



  1. Sharks have a excellent sense of smell. They are well known for their ability to detect minute quantities of substances such as blood in the water.
  2.  Sharks can detect a concentration as low as one part per billion of some chemicals, such as certain amino acids.
  3.  A shark’s sense of smell functions up to hundreds of yards away from the source.
  4. Water continually flows through the nostrils, giving the shark olfactory information.
  5. Unlike humans, shark nostrils have nothing to do with breathing and they are not even connected to the mouth. Their nostrils take in water and flush it out, picking up scents in the ocean.  It does not flow back into their gills.

There are so many fascinating things about sharks that would take all week to share with you. In my series, Brothers of Element, I tried to give every animal function a use when in human form.

Thanks for taking the time to share with us.

——–Drew has her first exam after going beneath the currents—–

Carina slid an arm through hers. “Are you alright, my Queen?”

“Yes. Startled, bewildered, and flabbergasted, but alright.” Even if none of this were true, there stood Dagger. She sighed. Little things he did endeared him to her more and more. “Question—birth control—tiger sharks carry over a year, with about eighty eggs fighting to survive.”

“Not in human form,” Dr. Sarah assured her. “And tiger shark women are only fertile every three years and have single or maybe a twin birth,” Dr. Sarah said, hands in her lab coat pockets, resting a hip along the sink. “Human fertility I have no experience with, although I have familiarized myself with the human anatomy in preparation of your arrival. Your spine shows a slight misalignment. The childhood injury I presume?” she queried. “The body protects itself when under attack and a pregnancy is an intrusion, a natural one, yet still an intrusion. I will have to go over the x-rays to be certain, but I do not believe this is a permanent state for you. Normally, I would recommend full bed rest after five months. In your case I will examine you after you meet Clear Coral.”

Tossing a look between women, Drew said, “And she will what?”

Dr. Sarah smiled as she uncrossed her ankles and said, “Our legend and existence stems from emotion. If you are whom we believe you to be, Clear Coral will comfort that which has been abused with in you.”

“Abused. You mean, it’ll fix what’s broken?”


“And birth control?”

“Pregnancy is by choice. You request the male’s fertilizing sperm.”

She pinched the bridge of her nose. “I need to write this down.”

“We have surrogates… if pregnancy becomes detrimental to your health. And do not be concerned; our children do not take on their animal until adolescence. He or she will appear human in form, outside of their coloring.”

Carina added, “Tiger and bull sharks tend to show signs of change earlier than most other species.”

She scrubbed a hand up her arm to cover her shoulder and felt the shark under her fingers. She was becoming one of them.

 Drew’s in for an adventure. 

Sincerely, Cora Blu.