Page 28. " He saw the phosphorescence of the Gulf weed in the water "
Artist's rendering of various types of plankton
Public DomainArtist's rendering of various types of plankton
Gulf weed, or Sargassum
Public DomainGulf weed, or Sargassum

Phosphorescence is the phenomenon whereby ocean water glows in the dark when disturbed. It's actually caused by bioluminescent plankton.

Gulf weed is another name for Sargassum (referred to later in the novel as "Sargasso weed"), a common brown seaweed.

Page 28. " there was a sudden deep of seven hundred fathoms "

A fathom is equal to six feet or 1.83 meters. Thus 700 fathoms would be 4200 feet (about 8/10 of a mile) or 1281 meters deep.

Page 28. " Here there were concentrations of shrimp and bait fish and sometimes schools of squid "
Shrimp: before
Public DomainShrimp: before

Shrimp are small crustaceans that are a popular seafood.

Shrimp: after
Public DomainShrimp: after

The term "bait fish" is a generic term for various small fish caught to serve as bait for larger fish.







Squid: after (fried calamari)
GNU Free Documentation LicenseSquid: after - Credit: Chensiyuan
Squid: before
GNU Free Documentation LicenseSquid: before - Credit: Fir0002/Flagstaffotos

Squid are cephalopods (similar to octopus) with elongated bodies and ten arms. They are fast swimmers and can grow very large.

When served as seafood, they are called calamari.

Page 29. " he heard the trembling sound as flying fish left the water and the hissing that their stiff set wings made as they soared away in the darkness. "
Small flying fish
Creative Commons Attribution Share AlikeSmall flying fish - Credit: Dr Jean Fortunet Jdontfight

Flying fish are, well, fish that can fly - short distances, at least. They are found anywhere with warm ocean water. Santiago thinks of them as his "principal friends on the ocean" because he knows when he sees them that the larger fish that prey on them are likely to be nearby.


Page 30. " spoke of her as el mar, which is masculine. "

La mar ... or el mar?
Creative Commons Attribution Share AlikeLa mar ... or el mar? - Credit: rachel_thecat, Flickr
In Spanish nearly all nouns are either feminine or masculine, regardless of whether the entity has sexual characteristics or not. In general, feminine nouns end in -a and are referred to with the definite article la; masculine nouns end in -o and are referred to with the definite article el. (There are many exceptions to these rules.)

So, for example, the English word pen is la pluma in Spanish (feminine). Dog is el perro (masculine), regardless of whether the dog is male or female.

The Spanish word for sea, mar, "is usually masculine, but it becomes feminine in some weather and nautical usages (such as en alta mar, on the high seas)." Thus it is a "noun of ambiguous gender."

Page 30. " Today I'll work out where the schools of bonito and albacore are "
Public DomainBonito

Albacore, or tuna
Public DomainAlbacore, or tuna
Bonito are mackerel-like fish that can grow up to 30 inches (75 cm) in length.

Albacore is another name for tuna. "Atlantic tunas vary greatly in size, from the skipjack and blackfin, which rarely exceed three feet (90 cm) in length, to the northern bluefin–the world’s largest living bony fish–which can attain a length of over 10 feet (300 cm) and weigh well over half a ton" (

Page 31. " on the others, he had a big blue runner and a yellow jack "
Blue runner
Public DomainBlue runner
Yellow jack (a reference to the fish, not the guy in the trunks)
Public DomainYellow jack (a reference to the fish, not the gentleman in the trunks)
The blue runner is a common medium-sized (35-70 cm or 14-28 inches) marine fish.

The yellow jack is a somewhat larger marine fish, averaging in length from about 45 cm to 1 m long (18-39.5 inches).

Page 33. " Just then he saw a man-of-war bird with his long black wings circling in the sky ahead of him. "
Man-of-war bird, more commonly known as the magnificent frigatebird
GNU Free Documentation LicenseMan-of-war bird, more commonly known as the magnificent frigatebird - Credit: Benjamint444

The man-of-war bird is more commonly known as the magnificent frigatebird. The males are equipped with a bright red throat pouch. To see additional photos and to hear the bird, click here.

Page 35. " the purple, formalized, iridescent, gelatinous bladder of a Portuguese man-of-war "
Portugues man-of-war
Public DomainPortuguese man-of-war
Portuguese man of war
Public DomainPortuguese man-of-war

The Portuguese man-of-war (sometimes "man-o'-war") is a fascinating organism. Its venomous tentacles are extremely painful but not generally deadly to humans.

According to, it "is . . . not a jellyfish, it's not even an 'it,' but a 'they.' The Portuguese man-of-war is a siphonophore, an animal made up of a colony of organisms working together." Its "float [is] 12 in (30 cm) long, 5 in (12.7 cm) wide; tentacles, up to 165 ft (50 m) long."

Page 35. " 'Agua mala' the man said "

"Agua mala" is Spanish for "bad water."

Page 36. " welts and sores on his arms and hands of the sort that poison ivy or poison oak can give "
Poison Ivy
Public DomainPoison Ivy
Poison oak
Public DomainPoison oak
Welts from contact with poison ivy
Public DomainWelts from contact with poison ivy

Poison ivy and poison oak are two plant species that release urushiol, an oily substance that causes a skin rash when touched.


You can learn more about them from the Poison Ivy, Oak, & Sumac Information Center.

Page 36. " the old man loved to see the big sea turtles eating them "

The video below shows the Portuguese man-of-war, the man-of-war fish (mentioned on pages 35-36), and a loggerhead turtle eating a man-of-war.


Page 36. " He loved green turtles and hawk-bills with their elegance and speed and their great value and he had a friendly contempt for the huge, stupid loggerheads "
Green sea turtle
Public DomainGreen sea turtle
Hawksbill Turtle
Creative Commons Attribution Share AlikeHawksbill turtle - Credit: Clark Anderson/Aquaimages










Loggerhead turtle
Creative Commons Attribution Share AlikeLoggerhead turtle - Credit: Strobilomyces
Page 37. " He was sorry for them all, even the great trunk backs that were as long as the skiff and weighed a ton. "

"Trunk backs" is another name for leatherback sea turtles:


Page 37. " He also drank a cup of shark liver oil each day "

According to, "Shark liver oil is promoted as a dietary supplement used to boost the immune system, fight off infections, heal wounds, and to treat cancer and lessen the side effects of conventional cancer treatment."



Page 45. " I'm the towing bitt. "

The towing bitt is a post on a boat to which something towed behind the boat can be secured. The old man uses the term ironically here--he is the bitt (the "post" to which the line is secured), but the boat is not towing something; it is itself being towed by the great fish.

Page 46. " He rested sitting on the un-stepped mast and sail "

Stepping a mast is the process whereby the mast is inserted into the boat's keel. Hence, an "un-stepped mast" is a mast that is lying in the boat, not vertical. The video below shows time-lapse photography of the mast-stepping process.


Page 46. " I can always come in on the glow from Havana. "
Havana, Cuba (in red)
Creative Commons Attribution Share AlikeHavana, Cuba (in red) - Credit: Morwen
Havana is Cuba's capital and largest city. For more information, see Setting.
Page 48. " During the night two porpoises came around the boat "
Dall's porpoise
Creative Commons AttributionDall's porpoise, type of porpoise found in the North Pacific - Credit: Travis S.

Porpoises, like dolphins and whales, are marine mammals--that is, they are warm-blooded and give birth to live young. They are generally smaller than dolphin—"seldom more than six feet (1.8 m) long—and [have] a blunt muzzle instead of a pointed one."

Page 49. " a colour almost like the backing of mirrors "

Woman looking in mirror, crayon drawing, 1918
Public DomainWoman looking in mirror, crayon drawing, 1918
According to, "Silver was the most popular mirror backing one hundred years ago. . . . More recently, before 1940, mirror manufacturers used mercury because it spread evenly over the surface of the glass and did not tarnish. This practice . . . posed the problem of sealing in the toxic liquid. Today, aluminum is the most commonly used metallic coating for mirrors."