Friday, January 30, 2015

Just another case of mistake identity

Why Great White Sharks Try to Eat Boat Engines 
Jan 23, 2015 08:41 AM ET // by Jennifer Viegas



Fishermen for years have told tales about huge sharks trying to eat their motorboat engines, and now videos are proving this does indeed happen.

Shark experts believe that great whites, like the one seen in the below video shot just a few days ago, are attracted to electrical pulses emitted by some boat motors.

"He had the entire trolling motor in his mouth, and was moving it side to side, and it was shaking the boat," said Captain Scott Fitzgerald of Madfish Charters to news station WMBB. "I've been chartering for nine years, and I've never seen a shark try to attack my boat. It was very exciting for all of us. It really got our hearts beating hard."

The encounter, documented in more videos at Madfish Charters' Facebook page, happened about eight miles into the Gulf of Mexico off of Panama City Beach, according to the report. Fitzgerald and his crew could see the shark coming at them. They estimate that it was at least 10 feet long.

Fitzgerald said that the shark circled three times. During each go around, the great white would bite into the motor, which is brand new. Fitzgerald eventually had to leave the area, taking his now shark-bitten trolling motor with him.

Given that the metal motor could break off shark teeth, one has to wonder why a great white would chomp into one in the first place.

South Carolina Aquarium Shark Expert Arnold Postell explained to Owen James Burke at thecuttlefish.com, "Sharks have the ability to detect electromagnetic fields with their Ampullae of Lorenzini. These are 'jelly'-filled pores at the tip of the nose/snout of elasmobranchs designed to pick up minute electric pulses put off by muscle contractions of their prey."

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Some boat motors must then give off electric pulses that are very similar to those of marine animals, confusing sharks.

Adding to the problem is that sharks tend to "taste" potential food items, be they a human leg or an old inner tube, to see if they're worth eating. In the vast ocean, food options can be feast or famine.

The shark probably tasted the motor repeatedly to see if it was worth eating. Fitzgerald kept pulling the motor up, away from the shark, which probably tempted the large predator all the more.

In any case, both shark and human survived the encounter.

Photo: Shark-bitten trolling motor. Credit: Madfish Charters



Thursday, January 29, 2015

TBT

My son found this and wanted to share it on the blog. 
 Throw back to Shark Week, Happy Thursday!

Thanks Major!

Wednesday, January 28, 2015

Global Warming?

Pacific Coast Shark Attacks Up During 2014, 'Three Times' Historic Average 


LA JOLLA, California -- There were 6 authenticated unprovoked shark attacks on humans reported from the Pacific Coast of North America during 2014. 


All of the attacks were recorded from California. The attacks were distributed in the following months; July (1), October (4) and December (1). Activities of the victims were; 3 Surfing, 2 Kayaking, and 1 Outrigger. The Great White Shark, Carcharodon carcharias, was positively identified or highly suspect in all 6 unprovoked attacks. Only two individual's sustained physical injury, both were surfing. 

http://indosurflife.com/wp-content/uploads/2012/07/Shark-Kayak.jpg

The boat incident in November in Central California is not considered in this analysis due to the activity of fishing, which might have attracted the shark to the vessel.

The publication "Shark Attacks of the Twentieth Century" authenticated 108 unprovoked shark attacks from the Pacific Coast between 1900 and 1999. 


The Great White Shark was implicated in 94 (87%) of the 108 confirmed attacks with an annual average of slightly more than one shark attack per year. The 6 cases reported for 2014 brings the total number of unprovoked shark attacks occurring along the Pacific Coast during the 21st Century to 83. 

This is 'three times' the Twentieth Century annual average of slightly more than 2 shark attack per year during the period 1950 – 1999. 

The Great White Shark was positively identified or highly suspect in 73 (88%) of the 83 attacks recorded during the 21st Century. From 2000 to the present, 42 (51%) of the 83 confirmed attacks occurred during the three month period of August (12), September (9), and October (21).

 There have been 191 authenticated unprovoked shark attacks reported from the Pacific Coast of North America from 1900 to 2014. The Great White Shark was positively identified or highly suspect in 167 (87%) of the 191 cases. 

There were 8 fatal shark attacks confirmed from 1900 to 1999 and 5 fatal attacks reported from 2000 to 2013. The 13 fatal attacks represent 7% of the 191 total cases.

Victim activity for the 83 shark attacks reported from the Pacific Coast since 2000 are distributed in the following ocean user groups; surfers 54 (65%) of the documented attacks, with 6 swimmers (7%), 11 kayakers (13%), 4 divers (5%), 4 paddle boarders (5%), 1 windsurfer (1%), 1 shore fishing (1%), 1 Stand-Up-Paddling Outrigger (1%) and 1 boogie boarder (1%). 


The number of shark-bitten stranded marine mammals reported for the Pacific Coast of North America in 2014 was slightly less than the prior year, especially in Santa Barbara County. 

This artifact might not necessarily be the result of a decrease in the number of sharks or pinnipeds but rather fewer individuals reporting these events to recognized organizations or individuals. The Shark Research Committee will continue to closely monitor these activities.