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This is my project about the Humboldt squid and it's rapidly expanding territory.
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Imagine, you are a scuba diving 300 meters below the surface off the coast of Máncora, Peru. Its freezing cold even in your dry suit. The red deep water light from your camera makes your surroundings increasingly eerie. Aside from the sparse distribution of krill you begin to think there is no life down here, when out of the corner of your eye, you see several ghostly forms flash by.
Unexpectedly, something grabs hold of you. Ten tentacles as thick as your arm equipped with razor-sharp barbs are wrapping around your head, threatening to pull off your mask and breathing apparatus. As you fight back you realize the futility. This creature has complete control of you in this environment. This is its territory.
As your camera falls to the depths, the red light reveals a gleaming black beak at the center of its mass yawning for your flesh. This is the end. Then, as quickly as it came, it disappears, leaving you drifting in complete, senseless terror.
You just been attacked by a red devil, the most fearsome predator of the deep.
ATTACK FROM THE DEEPThe Expanding Territory of the Humboldt Squid (Dosidicus gigas)
By Jack Fitch: Dr. Mike Valentine’s Oceanography Class 2009
My Early Work
• Extensive cephalopod research since elementary school
Squid Art and Analysis
El Diablo Rojo
• Molluska Cepholapoda – Predator– “Pen” internal shell
• Characteristics – Up to 100 lbs, 6 ft long– Well developed neuro.– 10 legs– Fast growing
• Habitat– oxygen minimum zone (OZM)– Low productivity + high
decomposition = low oxygen• 600-3000 feet deep
The Humboldt Current
• Discovered in 1800• Alexander von
Humboldt– German Naturalist– Pioneer
• Modern thinking• Ecology
High Productivity– Gyre
• Corollis Effect
– The Most Productive• Nutrient rich Upwellings
• 1% of the ocean
• 15-20% of the World’s Marine Catches
– Economic Dependence• Many coastal fisheries
• 20 million tons/year
Hunting and Feeding
• Opportunistic– Few organisms can
survive the low oxygen environment
– Wide range of prey• Hape, sardine,
anchovy, rock fish and market squid
• Important economical fish…
Voracious Predator
• Cone-shaped attack and razors– “Corn on the cob”
• Fast growing– 2 inches to 6 feet in 24 months
Cool Characteristics
Jet propulsion up to 25 mph!
Chromatophores
Ink
Normal Distribution
• Eastern equatorial Pacific
Invasive Distributions
• 1930’s: The Gulf of California– 70 year disappearance
• 1997: Return– After El Nino
• 2002 Return• 2004 Return• 2005 return
Causes?• Largely Unknown• Possible Causes
– Increasing Temperatures• El Nino y la Nina• Global Warming
– Human Impacts?
– Expanding OMZ• More Prey• Larger Territory
– Overfishing• Tuna, Marlin, swordfish and
sharks• Competetors Decreasing
– The Perfect Combination?!
More Causes
• No Competition– Overfishing
• Tuna, Marlin, swordfish and sharks
• Only 1 healthy predetor
• The Perfect Combo?!– Warming currents– No competetors– Very well adapted
Effects• Economic and Ecologic
– Top down pressure– More squid = less prey
species
• Northwest Examples of Invasion
Sohphisticated Data Gathering
• Very little is known about D. gigas
• Stanford University Professor William Gilly – Sat. tags
• Every second for 1 month-Depth-Temperature-Light
• After 1 month-Detach, rise and transmit
• Reward$
Sources– Zeidberg, D.Z. and Robinson, B.H., 2007 Invasive range expansion by the Humboldt
squid, Dosidicus gigas, in the eastern North Pacific: PNAS, v. 104, pp 12948- 12950.
– Sachs, Aaron 2006, The Humboldt Current: Ninetheenth-Century Exploration and the Roots of American Environmentalism, Viking Books, New York,
New York. – Wheeler, K., and D. Fautin, 2001 "Cephalopoda" (On-line), Animal Diversity Web.
Accessed June 11, 2009 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Cephalopoda.html.ttp://animaldiversity.ummz.umich.edu/site/accounts/information/Cephalopo da.html
– Fréon, P., Bertrand, S., 2004 Large Upwelling Ecosystems of the World: Les dossiers thématiques de l’IRDhttp. Accessed June 14, 2009 at ://www.mpl.ird.fr/suds-en- ligne/ecosys/ang_ecosys/upwelling/humboldt.htm