Getting the Most Out of Your Underwater Experience: An

Transcription

Getting the Most Out of Your Underwater Experience: An
Getting the Most Out of Your
Underwater Experience:
An introduction to identifying the fish,
creatures, and coral of the Virgin Islands
Part I: Fish
Brian Naess, Research Associate
Institute for the Environment, UNC-Chapel Hill
Credits
• All photos, except where noted, taken by ENST
259 instructors: Brian Naess, Liz Naess, Andrew
George
• All identifications for class photos based on the 3
book series by Paul Humann and Ned Deloach:
Reef Fish Identification, Reef Creature
Identification, and Reef Coral Identification of
Florida, Caribbean, and Bahamas published by
New World Publications, Inc.
3 Main Divisions
• Fish – sharks, eels, rays
• Creatures – crabs, shrimp, clams, starfish,
anemones, lobsters, squid, octopus,
worms, cucumbers, tunicates, sponges,
urchins
• Coral – hard and soft varieties, algae
Fish
* Images scanned from Reef Fish Identification: Florida, Caribbean, Bahamas by Paul Humann and Ned DeLoach
Focus on One Fish at a Time!
What to Look For
1a) Shape
1b) Distinctive Traits
2) Color
3) Behavior
4) Location
5) Size
“Seven Dookies Came Back Looking Sad”
Fish Anatomy
Shape
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General body shape
Head – slope of head/nape, mouth
Tail – forked, fan, square or round
Dorsal fin(s) – tall, short, spiked or
feathered
• Pectoral – large, small, obvious
• Don’t be fooled by:
– Some fish are shaped differently in juvenile
stages!
Distinctive Markings/Physical
Properties
• Bars, stripes, spots, “makeup”,
etc.
• Unique dorsal fins or other
appendages
• Big eyes
• Don’t be fooled by:
– Many fish can change colors
instantly, including adding bars by
darkening certain areas and
lightening others
– Some times the distinctive mark can
be quite difficult to see
Color
• Silvery?
• Can be as distinctive as a marking or
physical property
• Don’t be fooled by:
– I repeat! Fish can change colors instantly!
– Juvenile coloring can be drastically different
from adults
Behavior
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Bold? Shy? Protective?
In the open or under cover?
Schooling
Common associations
Night/Day
Feeding
Don’t be fooled by:
– Fish are TERRIFIED of YOU! They may take a while
to get used to you.
Location
• Habitat
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Coral
Sea grass
Sand/Rubble
Blue water
• Depth
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Shallow swimmers
Mid-reef
Reef’s edge/drop-off
Bottom dwellers
• Don’t be fooled by:
– Fish swim!
Size
• Many species only reach a given size. If
deciding between two possibilities, size
may help decide the matter
• Juveniles complicate the matter
• Don’t be fooled by:
– Things look bigger underwater!
Quiz
French grunt*
Distinctive features: Yellow stripes below lateral line set on diagonal.
Description: Yellow stripes on a white to bluish or yellowish silver background.
Stripes above lateral line are horizontal. Fins yellow.
Habitat and Behavior: Prefer coral reefs. Often congregate in small to large schools,
which may number in the hundreds, in the shade of bottom formations.
* Description taken from Reef Fish Identification: Florida, Caribbean, Bahamas by Paul Humann and Ned DeLoach. Page 93
Quiz
Blackbar soldierfish*
Distinctive features: Black bar behind head.
Description: Bright red to, on rare occasions, pale red. Red dorsal fin has white
marks at tips and a few along base. White borders on leading edge of ventral, anal,
rear dorsal and tail fins.
Habitat and Behavior: Hide in dark recesses. Often gather in large to huge schools.
* Description taken from Reef Fish Identification: Florida, Caribbean, Bahamas by Paul Humann and Ned DeLoach. Page 242
Quiz
Slippery dick (not quite Terminal Phase)*
Distinctive features: Small green and yellow bicolored spot above pectoral fin. Dark
triangular corners on tail.
Description: Shades of green. Colors and markings vary greatly.
Habitat and Behavior: Constantly swim about reefs, adjacent sand areas and grass
beds.
* Description taken from Reef Fish Identification: Florida, Caribbean, Bahamas by Paul Humann and Ned DeLoach. Page 222
Photo by Jaime Neill
Quiz
Trumpetfish*
Distinctive features: Long, thin body. Trumpet-like mouth.
Description: Three color variation: the most common is brown to reddish brown; can
be blue-gray with purpulish head or bright yellow; also able to pale or darken. Have
pale lines, scattered small black spots, and a black streak on upper jaw.
Habitat and Behavior: Inhabit coral reefs. Change color, and position their bodies to
blend with background. Often drift in vertical position, head down, paralleling stalk of
sea rods. May attempt to camouflage themselves by hovering just above larger fish
as they move about the reef.
* Description taken from Reef Fish Identification: Florida, Caribbean, Bahamas by Paul Humann and Ned DeLoach. Page 380
Quiz
Scrawled filefish*
Distinctive features: Covered with blue to blue-green spots, irregular lines and black
dots. Elongate body with long, broom-like tail.
Description: Vary from pale gray or tan to dark olive-brown. Can darken or pale
dramatically. Tail often closed and limp.
Habitat and Behavior: Inhabit coral reefs. Drift over reefs, often in open water.
* Description taken from Reef Fish Identification: Florida, Caribbean, Bahamas by Paul Humann and Ned DeLoach. Page 398
Quiz
Chain moray*
Distinctive features: Pale yellowish to bright yellow chain-like markings.
Description: Heavy body. Dark brown to black, with irregular, often interconnected,
bright yellow bars. Yellow eyes.
Habitat and Behavior: Prefer shallow, clear-water reefs and rocky shores. Hide
during the day in recesses; heads often extend from openings.
* Description taken from Reef Fish Identification: Florida, Caribbean, Bahamas by Paul Humann and Ned DeLoach. Page 430
Tips for Productive Snorkeling
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Good fitting mask
Take your time
Reefs are 3D – swim down and explore
Don’t use fins in shallow water
Stay horizontal in water less than 15’ deep
Look for overhangs, openings, caves
Focus on one thing at a time
Spend some time in the shallows
Little fish are just as cool as big fish!
Questions?
Banded butterflyfish
Back
Yellowtail snapper
Flat needlefish
Spotted trunkfish
Dog snapper
Orangespotted filefish
Bar jacks
Sergeant major
Back
Back
Balloonfish
Striped parrotfish
Great barracuda
Red hind
Dusky squirrelfish
Back
Honeycomb cowfish
Yellowtail parrotfish
Barbfish
Back
Nurse shark
Gray angelfish
Rosy blenny
Back
Stoplight parrotfish
Smooth trunkfish
Banded butterflyfish
Queen triggerfish
Back
French and bluestriped grunt
Spotted drum
Pompano
Back
Yellow goatfish
Highhat
Back
Reef squirrelfish
Glasseye snapper
Back
Mutton snapper
Mutton snapper
Back
Bluehead wrasse (juv.)
Silversides
Blue tang &
ocean surgeonfish
Back
Whitefin sharksucker
Blue tang &
ocean surgeonfish
Spotted eagle ray & sharksucker
White mullet
Back
Saucereye porgy
Cero mackerel
Blue and Brown chromis
Back
Redband parrotfish
Yellowtail snapper
Back
Red hind
Orangespotted filefish
Back
Trunkfish
Yellowhead jawfish
Back
Southern stingray
Yellowfin mojarra
Palometa
Peacock flounder
Back
Sand Diver
Back
Rock beauty
Bluehead
Back
Flat needlefish
Glassy sweeper
Back
Spinyhead blenny