A Research-Based Middle and High School Classroom Resource

www.marine-ed.org/bridge/survivor.pdf

Created by: Susanna Musick & Lisa Lawrence Virginia Institute of Marine Science Gloucester Point, VA 23062

Version 09.25.06

S E A TURTLE SCIENCE

Sea Turtle Quick Facts

BIOLOGY

• In the Atlantic, sea turtles are found from Mas-

Atlantic Sea Turtle Species

sachusetts to Florida and throughout the Gulf of Mexico. Leatherbacks extend north to Ice-

Leatherback (Dermochelys coriacea) land.

Size: 1.8 m (6 ft), 727 kg (1 ton)

• Sea turtles are found in the tropics to sub- tropics year-round and higher latitudes in sum-

Diet: jellyfish Status: endangered

mer.

• Sea turtles feed in shallow waters (except leath- erbacks).

Green (Chelonia mydas) Size: 1 m (3.3 ft), 150 kg (68 lb) Diet: Juveniles—molluscs, crustaceans, jellyfish

• Sea turtles migrate from foraging grounds to mating grounds. Most nest in tropics (except

Adults—seagrasses, macroalgae Status: endangered (FL)/ threatened loggerheads which nest in temperate areas)

• Females come onshore only to nest; aside from occasional basking, males spend entire life in water.

Loggerhead (Caretta caretta) Size: 0.92 m (3 ft), 115 kg (52 lb) Diet: benthic crustaceans & molluscs Status: threatened

• Females will nest multiple times in a season, but generally nest only every other year.

Hawksbill (Eretmochelys imbricata) Size: 0.66-0.86 m (2.2-2.8 ft) 82 kg (37 lb) LIFE CYCLE

• A clutch of 50-170 ping pong ball-like eggs

Diet: sponges & benthic invertebrates Status: endangered incubate for 6-13 weeks.

• Hatchlings emerge from nest and head to- wards brightest horizon.

Kemp’s Ridley (Lepidochelys kempii) Size: 0.58-0.80 m (1.9-2.6 ft) 40-50 kg (18-23 lb) Diet: crabs, shrimp, molluscs

• A “swimming frenzy” occurs as they hit water

Status: endangered and head towards open ocean.

• In the “Lost Years” loggerheads are believed to

REFERENCES Wynne, K. & M. Schwartz. 1999. Guide to Marine spend early juvenile years feeding in the Sar- Mammals & Turtles of the U.S. Atlantic & Gulf of gasso Sea.

Mexico. Rhode Island Sea Grant, Narragansett, RI.

• Older juveniles join adults in coastal feeding or

114 pp.

mating grounds, except leatherbacks which remain pelagic.

• Females return to their natal regions to breed and nest.

• Reproductive maturity for some species occurs after 10-30 or more years, life span may be more than 50 years.

REFERENCES Lutz, P.L. & J.A. Musick, (eds.). 1997. The Biology of Sea Turtles. CRC Press, Boca Raton, FL. 432 pp.

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NATIONAL SCIENCE EDUCATION

possible to identify the species of the turtle that emerged by the tracks STANDARDS CORRELATIONS

left in the sand. Key crawl characteristics include:

Science as Inquiry Ability to do scientific inquiry (K-12) Understanding of scientific inquiry (K-12)

$ Alternating or simultaneous right and left flip-

per marks $ Presence or absence of tail marks down the

center of the tracks Life Science Life cycles of organisms (K-4)

$ Relative width of tracks indicating the size of

the turtle Organisms and environments (K-4) Populations and ecosystems (5-8) Reproduction and heredity (5-8) Regulation and behavior (5-8) The behavior of organisms (9-12) The interdependence of organisms (9-12)

Loggerhead sea turtle tracks are smaller on aver- age than green and leatherback turtle tracks. They exhibit alternating right and left flipper tracks and no tail marks. Both green turtles and leatherbacks exhibit simultaneous right and left flipper marks and the presence of tail marks down the center of Science in Personal and Social Perspectives Characteristics and changes in populations (K-4)

the tracks (LeBuff, 1990). Leatherback tracks are the widest of all species' tracks. Populations, resources, and environments (5-8) Natural resources (9-12) Natural and human-induced hazards (9-12)

Tracks indicate the direction in which the turtle was traveling. Examining where the turtle pushed the sand back in an effort to move herself forward aids in determining the turtle’s direction of travel. Determining direction helps identify where she may have nested. With old tracks, direction may be Sea Turtle Nesting Behavior

difficult to determine.

by Kate Mansfield, VIMS

THE BODY PIT Once the female has chosen a nesting site, she All sea turtles share a similar behavior pattern when nesting. Most turtles found nesting on the east coast of the United States have distinct "trademarks" or characteristics which can be used to identify what species of turtle nested. Typically this can be accomplished through the examination of the tracks or the nest site. Becoming familiar with the nesting process and the "trademarks" of each turtle enables beach monitors to more accu- rately identify what species of turtle was present, and whether the turtle laid eggs or not. The fol- lowing is a step by step behavioral process that nesting sea turtles typically follow.

prepares the area by clearing the sand and brush- ing it away with all four flippers. In some cases, she excavates a large pit with her flippers. Loggerhead turtles make relatively shallow body pits, commonly in the form of two long, narrow hills of sand on either side of the turtle's tracks moving towards her nest site. Green turtles, however, have a character- istically large and deep body pit. Greens may leave a body pit that is one to two meters in diameter and up to .5 to 1.0 meters deep. Hawksbill sea tur- tles create little to no body pit and usually nest in the brush landward of the open beach. Both log- gerhead and green turtles tend to nest on the open beach. THE CRAWL Generally, female sea turtles swim in towards shore during the late afternoon or early evening just prior to sunset. At some point after nightfall, the nesting turtles emerge from the ocean and crawl up the beach to find a suitable nesting site. It is

THE EGG CHAMBER Upon completing the body pit, turtles excavate an egg cavity with their rear flippers. Using these flip- pers as shovels, the turtles scoop out sand from the egg chamber, alternating flippers as they dig. Sand

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that is scooped out of the cavity is spread to the

back and green turtles both leave side of the hole. The depth of the egg chamber is

characteristically large and widely flung determined by the length of the rear flippers (van

mounds of sand. When covering is complete, the Meter, 1983). If a turtle is missing a large portion of

turtle crawls back to the ocean, leaving tracks as one or both of her rear flippers, her egg chamber

she exits the beach. may be relatively shallow. The shape of most egg chambers beneath the sand resembles an inverted

FALSE CRAWLS VS. NESTS light bulb.

Occasionally, a nesting turtle may emerge from the ocean but not lay eggs on the beach. This event, LAYING THE EGGS

characterized by an abandoned nesting attempt When the egg chamber is completed, the turtle

or simply a U-shaped crawl from the ocean up the starts depositing her eggs. Once a turtle begins to

beach, then back to the water, is called a False lay her eggs, she becomes almost oblivious to any

Crawl, Emerge No Lay, or Abandoned Nesting disturbance around her. Most loggerhead turtles

Attempt. A turtle may false crawl for a number of spread their rear flippers beside their nest during

reasons, some of which include: deposition. The turtles position their cloaca over

$ She is disturbed by lights, noise or other un- the hole and begin dropping eggs, two and three

usual activities at a time, into the chamber. Once egg laying com-

$ She encounters and obstacle while crawling mences, the turtles often slightly curl their rear flip-

up the beach pers as eggs are deposited. This action is an indica-

$ She encounters roots, debris or rocks while tor that the turtle has begun to lay her eggs and

digging her egg chamber can be approached by researchers without dis-

$ The sand does not have the right consistency turbing her. Unlike the loggerhead, leatherbacks

or moisture and green turtles generally extend their rear flip-

$ Her egg chamber collapses pers directly behind them during egg deposition

$ Other reasons not known (Ibid.). Some green turtles cover the exposed egg chamber with one of their rear flippers. With shal-

A turtle may false crawl at any point in her nesting low egg chambers, some eggs may spill out on

sequence up to the point where her eggs are laid. either side of the chamber. These eggs may be

A turtle may even complete her egg chamber and crushed by the turtle as she begins to fill in her egg

for some reason not deposit her eggs. The key fac- chamber after she deposits the clutch.

tor that indicates whether a turtle has laid her eggs or not is the presence or absence of a mound of COVERING THE EGGS

sand and the escarpment created when the turtle Once the turtle deposits all of her eggs, she covers

flung the sand back over her nest site. A turtle will the egg-filled chamber with sand, shoveling it in

not obliterate her nest site if she has not deposited and packing it down with her rear flippers. Some

eggs. species slap down or knead the sand, using the weight of their bodies to pack down the area.

HATCHLING BEHAVIOR Depending upon the species and the temperature NEST OBLITERATION

of incubation, the time between egg deposition When the turtle finishes covering and packing the

and hatchling emergence ranges anywhere from sand down on top of her eggs, she swipes sand

45 to 75 days (LeBuff, 1990). Within the first 12 with her front flippers, flinging it back over the nest

hours after deposition, the vitelline membrane (the site. A turtle ONLY does this if she lays her eggs

cell wall of the egg that plays an important role in (Florida Department of Natural Protection, 1994).

gas exchange through the egg wall) attaches to The resulting nest site has a characteristic mound

the interior of the egg shell (Ibid.). If the egg's ori- of sand over part of the turtle's tracks and nest site,

entation changes after the attachment forms, the as well as a small escarpment made from where

membrane detaches from the egg wall and devel- the turtle used her front flippers to scrape away at

opment ceases (Ibid.). Great care is usually taken the sand, flinging it back over her nest. Leather-

by researchers if eggs must be moved for any rea-

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son more than six to twelve hours after a turtle has

LITERATURE CITED nested.

Ehrenfield, D. W. 1968. The role of vision in the NEST EMERGENCE sea-finding orientation of the green turtle After incubating beneath the surface of the sand (Chelonia mydas) 2. Orientation range and spec- for approximately two months, the young turtles

tral sensitivity. Animal Behavior 16:281-287. begin to hatch out of their shells. Hatchlings may remain within the egg chamber several days after

Florida Department of Natural Protection 1994. hatching. Hatchlings found in the process of crawl-

Nesting Beach Monitoring Techniques. TOPIC: ing out of their shell are called pipped. The move-

Crawl Identification. Monitoring protocol literature ment of fully hatched and pipping turtles while in

from FL DEP. Tequesta, FL. the egg chamber serves to loosen the sand, allow- ing it to trickle down to the bottom of the nest.

Lebuff, C. R. 1990. The Loggerhead Sea Turtle in This process acts as a sort of elevator: the greater

the Eastern Gulf of Mexico. Caretta Research Inc., the movement caused by hatchlings, the greater

Sanibel, FL. Pp 185, 190. the amount of sand filtering down to the bottom of the nest, thereby elevating the turtles closer to

van Meter, V. B. 1983. Florida's Sea Turtles. Florida the surface.

Power and Light Company. Miami, FL. P 25.

Emergence occurs primarily at night. The tempera- ture of the surface sand and sun/ambient tem-

NOTES: perature during incubation are key factors that determine when hatchlings emerge from their nest. Once the surface layers of the beach cool after sunset or after a rain storm, the turtles 'erupt' en mass and proceed to crawl down the beach to the water (Ibid.). Hatchlings orient themselves to light reflected off the water and beach, away from the darker vegetated areas typically found land- ward along the beach (Ehrenfield, 1968). Over a hundred hatchlings may emerge from a nest at one time.

FRENZY From the time of nest emergence up to 24 to 72 hours after entering the ocean, hatchlings remain in a state often referred to as a "frenzy." During this period, hatchlings swim constantly. This may serve to get the hatchlings away from shore and coastal predators, out to deeper waters (van Meter, 1993). Very little is known about sea turtles from the point that hatchlings enter the ocean until at least 20 years later when the females become sexually ma- ture and come ashore again to nest. This lack of information makes sea turtle management and conservation difficult.

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Survivor!

on land, and in the water. On

land, human threats include egg Loggerhead Hatching Activity Created by Susanna Musick, Jack Musick, and Lisa Lawrence, Edited by Vicki Clark and Lee Larkin

harvesting, beach lighting and development, pollu- tion, vehicles, sea walls, beach compaction, and sand quarrying. In the water, anthropogenic ef- fects include turtle harvesting, bycatch, boat colli- BACKGROUND A variety of factors can affect the hatching success of sea turtles. Temperature, amount of moisture, sand grain type, and gas exchange all play a part in hatching success within the egg chamber. Out-

sions, and habitat degradation (including pollu- tion). These human threats lower survivorship esti- mates even further. Conservation of these threat- ened animals is important so that we may con- tinue to study and appreciate them in the future. side the nest, predators can also influence the suc- cess of the nest and hatchlings.

This activity is a modeling exercise that involves population estimates and natural (non-human) The average clutch count or number of eggs laid by loggerhead sea turtles is 112.4 eggs (Miller, 1997). Female turtles usually lay three to seven nests per season and nest every one to three years. Eggs that incubate for extended periods at tem- peratures lower than 23oC (73.4oF) or greater than 33oC (91.4oF) seldom hatch (Miller, 1997). The temperature profile will vary widely from beach to

mortality factors. Actual survivorship numbers are highly variable and differ from one population to the next. The activity scenario takes place on one nesting beach. Ten nests with 100 eggs each are laid (1000 eggs total). In this activity, we will follow the outcome of one of these nests. Each egg in the nest will actually represent 10 eggs from the entire nesting beach. beach, depending on tides, weather, and nest lo- cation. Temperature also determines the sex of the hatchling. The pivotal temperature for loggerhead sea turtles is 28.74oC (83.7oF). Generally if the nest's temperature has been below 28.74oC, most of the hatchlings will be males. If the temperature has been above 28.74oC, the majority will be fe- males (Ackerman, 1997). Eggs at the top of the nest have the highest risk of predation and over- heating. Eggs at the center of the nest have less of a risk of predation or inundation, but less gas ex- change. Eggs at the bottom of the nest are cooler, and at a higher risk for inundation, but at a lower risk for predation. Eggs will usually hatch after 6-13

OBJECTIVES $ Identify threats to sea turtle nests, hatchlings,

and adults $ Define factors limiting the development and

survival of eggs, hatchlings, and adults $ Discover characteristics of the nest environ-

ment $ Investigate the life history stages and habitats

of threatened and endangered species $ Learn about conservation and protection of threatened and endangered marine species $ Discuss percent mortality, survival of the fittest,

and management concepts weeks of incubation, depending on the tempera- ture (Miller, 1997). Usually, incubation period de- creases as incubation temperatures increase (Ackerman, 1997).

MATERIALS

• 100 ping pong balls (www.ballsonline.com)

• 10 gallon glass aquarium or clear plastic bin

• sand (enough to fill the aquarium 3/4 full) On average, there is an 80% hatching success rate

• small trowel or hand shovel for loggerheads. However, from the time they

• printout of Kate Mansfield’s excerpt on Sea Tur- leave the nest, hatchlings are exposed to many

tle Nesting Behavior threats. They may get lost, or die from disease, ex- haustion, and predators. It is estimated that only 1

PROCEDURE or 2 out of 1000 turtles will survive to maturity

Total time, 65 minutes (Frazer, 1986). This estimate does not include the negative impact of humans on the life cycle of tur- tles. Humans threaten sea turtles in various ways

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PREPARATION 20 minutes

1. Number eggs 1-100. 2. Cover the bottom of the tank with sand. 3. Place ping-pong balls (eggs) in a plastic bag and set in the aquarium against one of the long sides. Begin putting sand in the tank around the bag of eggs forming a flask-shaped chamber. Once most of the sand is in, remove the bag of eggs. Take the eggs out of the bag and place them in the hole or nest chamber. 4. After all the eggs are inserted in the nest cham- ber cover the opening with the remaining sand. 5. The nest chamber will be used to illustrate sex ratios in sea turtles. In general, northern areas with cooler beaches will produce more male turtles, and southern, warmer beaches will pro- duce more female turtles. Virginia is the north- ern most nesting area for loggerheads. Sex ratios vary highly from beach to beach. For most nesting beaches in Florida, about 90% of the hatchlings will be females (Mrosovsky, 1984). In Georgia and South Carolina, most nests will have an ap- proximate 50/50 ratio of males to females (Mrosovsky, 1984). In Virginia, about 90 % of the hatchlings will be males (Jones, 1998). Draw a line or tape an arrow onto one side of the tank indicating the pivotal temperature of 27.4oC. Designate the placement of the line based on your geographic location. If you are in a northern area near Virginia, place the line 1/4 down from the top of the nest. If you are near Georgia or South Carolina place the line halfway through the nest (see photo above). If you are near Florida or far- ther south, place the line 1/4 up the side from the bottom of the nest. During the activity, students will remove the eggs from the nest. Eggs removed above the line will be females and eggs removed below the line will be males.

CLASS ACTIVITY 45 minutes Students should read Kate Mansfield’s article on Sea Turtle Nesting Behavior (p.3). Discuss the nest environment and factors such as temperature, moisture, position of the egg, predators, etc. that determine the outcome of the eggs and hatch- lings.

Uncover the nest chamber by removing sand and ask students to take turns removing eggs from the chamber. If possible, each student should extract the same number of eggs from the nest. For ex- ample, if you have 25 students and you use 100 eggs, each student will have 4 eggs.

Based on the position of the egg in the nest, each student records the sex of his or her eggs on the board. Was each hatchling a male or female?

Discuss why there were more males or females in the nest based on its location (in a warm or cold beach).

STAGE ONE: Hatching success (eggs hatch after 6-13 weeks of incubation) Using the tables for the life history stages (p.8), call out the numbers for the eggs that failed to survive and ask students to look up (p.8) the factors that contributed to their mortality. Discuss the factors that contributed to mortality. Record the percent survivorship and mortality on the board.

STAGE TWO: Year one survivorship (journey from beach to the pelagic gyres) This stage includes the journey from the beach to the surf, and the surf zone to the pelagic gyres. The hatchlings spend little time traveling from the beach to the gyre, so much of the first year is spent in the pelagic zone where juveniles are often found in large mats of Sargassum.

Announce the numbers for the eggs/turtles that survived the second stage. Ask the students to look up the factors (p.8,9) that contributed to their mortality. Discuss these factors and record the per- cent survivorship and mortality on the board. Why is mortality so high in this stage? Hint: What size are the turtles?

S E A TURTLE SCIENCE

STAGE THREE: Pelagic juveniles

LIFE HISTORY TABLES (duration ~ 8 years) Call out the numbers that survive this stage. Stu-

STAGE ONE dents continue to look up the factors that contrib-

80% overall survivorship, 20% overall mortality ute to mortality and discuss them. Record the sur-

Hatchling mortality (incubation = ~60 days) vivorship and mortality percentages on the board.

Egg # Factor Contributing to Death STAGE FOUR: Benthic juveniles (duration ~10 years)

4 Inundation with water

Announce the surviving eggs/turtles. Only two

8 Inundation with water students or eggs/turtles will remain.

13 Inundation with water

STAGE FIVE: Adults Since the remaining two ping-pong balls actually represent twenty eggs or turtles, the game will continue by having the final two students each

16 Not enough gas exchange 23 Eaten by ants 33 Eaten by ants 35 Eaten by ants pick a number from 1-10. If they choose 3 or 7

42 Trapped by plant roots then they survive to maturity. These final eggs/ turtles will actually be the turtles that survived from the 10 nests that were laid on the nesting beach (2 out of 1000 survivorship).

50 Trapped by plant roots 51 Erosion 55 Erosion 56 Erosion How many times will one female turtle need to

57 Eaten by a fox nest in order to have a stable population (i.e. re-

58 Eaten by a vulture place herself and one male)?

61 Nest temperature too cold

Wrap up the activity with a review of all the con- tributing factors that determine whether or not a sea turtle will survive to maturity. Ask students to think of human factors that could influence the

64 Bacteria 68 Eaten by a raccoon 75 Eaten by a raccoon 86 Desiccation (too hot, egg dried out) survivorship of the turtles. How might these fac-

96 Desiccation (too hot, egg dried out) tors effect the outcome of the game? (Example: If one of the surviving turtles had been run over by a car in stage one, and the other drowned in a fish-

STAGE TWO ing net in stage four, no turtles would survive). Dis-

Journey from nest to the shoreline, surf zone, and cuss why it is important to protect and conserve

gyres/pelagic zone (duration = 1 year) threatened and endangered marine species and

20% overall survivorship, 80% overall mortality how poaching, bycatch, pollution, and other hu-

Beach/shoreline man sources contribute to the decline of sea tur- tles.

Egg # Factor Contributing to Death 5 Eaten by a ghost crab 6 Eaten by a raccoon 28 Eaten by a vulture 34 Eaten by a seagull 36 Eaten by a ghost crab

(Stage Two continued on next page...)

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Egg # Factor Contributing to Death

Pelagic gyre (juveniles <1 year old)

46 Eaten by a tern

Egg # Factor Contributing to Death 54 Eaten by a raccoon

7 Eaten by a yellowfin tuna 59 Eaten by a ghost crab 88 Eaten by a night heron 92 Eaten by a fox

11 Eaten by a bluefin tuna

17 Eaten by a dolphin fish

93 Eaten by a wild hog

18 Eaten by a dolphin fish

100 Eaten by a fox

19 Eaten by a mako shark

21 Eaten by a sailfish

Egg # Factor Contributing to Death

25 Eaten by a silky shark

1 Eaten by a seagull

29 Eaten by a shearwater

9 Eaten by a spinner shark

38 Exhaustion 14 Eaten by a snapper

41 Eaten by a shearwater 15 Eaten by a jack

44 Eaten by a white marlin 20 Eaten by a blacktip shark

47 Eaten by a dolphin fish 22 Eaten by a sharpnose shark 24 Eaten by a young sandbar shark 26 Eaten by a pelican

65 Eaten by a dolphin fish

67 Eaten by a skipjack tuna

32 Exhaustion

73 Eaten by a frigatebird

37 Eaten by a cormorant

74 Eaten by a yellowfin tuna

40 Eaten by a frigatebird

76 Eaten by a frigatebird

43 Eaten by a speckled trout

78 Eaten by a mako 52 Eaten by a snook

79 Eaten by a whitetip shark 53 Eaten by a tarpon

82 Eaten by a frigatebird 66 Eaten by a bullshark 71 Eaten by a red drum 72 Eaten by a bullshark Surf Zone

94 Eaten by a frigatebird

97 Eaten by a seagull

77 Eaten by a Spanish mackerel

98 Eaten by a barracuda

81 Eaten by a tarpon

Eggs that survived Stage Two:

83 Eaten by a snook

2,3,10,12,27,30,31,39,45,48,49,60,62, 63,69,70,80,89,91,99 84 Eaten by a snapper 85 Eaten by a jack

(Stage Three continued on next page)

87 Eaten by a pelican 90 Eaten by a seagull 95 Eaten by a cormorant

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STAGE THREE 5% overall survival, 15% mortality Pelagic zone (juveniles 1-8 years old)

References

Ackerman, R.A., 1997. The Nest Environment and the Embryonic Development of Sea Turtles, in The Biology of Sea Turtles, Lutz, P. and Musick, J., Eds., CRC Press, 88.

Crouse, D.T., L.B. Crowder, and H. Caswell. 1987. A stage-based population model for loggerhead sea turtles and implications for conservation, Ecology, 68, 1412-1423.

Frazer, N.B., 1986. Survival from egg to adulthood in a declining population of loggerhead tur- tles.Caretta caretta. Herpetologica, 42 (1), 47-55.

Jones, W.M., 1998. Physical parameters affecting incubating temperatures in loggerhead sea turtles, Caretta caretta, in Virginia, M.sc. thesis, College of William and Mary, Williamsburg, VA, 91 pp.

Miller, J.D. 1997. Reproduction in sea turtles, in The Biology of Sea Turtles, Lutz, P. and Musick, J., Eds., CRC Press, 65-68.

Eggs that survived Stage Three: 27,30,48,91,99

Egg # Factor Contributing to Death 2 Eaten by a bluefin tuna 3 Eaten by a dolphin fish 10 Eaten by a whitetip shark 12 Eaten by a blue marlin 31 Eaten by a blue shark 39 Eaten by a dolphin fish 45 Eaten by a blue shark 49 Eaten by a blue shark 60 Eaten by a dolphin fish 62 Starved 63 Eaten by a whitetip shark 69 Eaten by a yellowfin tuna 70 Eaten by a barracuda 80 Eaten by a amberjack 89 Eaten by a wahoo

Mrosovsky, N. 1994. Sex ratios of sea turtles, Jour- nal of Experimental Zoology, 270, 17-27.

STAGE FOUR

National Marine Fisheries Service Southeast Fisher- Demersal juvenile to adult stage (10+ years)

ies Science Center. 2001. Stock assessments of log- gerhead and leatherback sea turtles and an assess- ment of the impact of the pelagic longline fishery Egg # Factor Contributing to Death

on the loggerhead and leatherback sea turtles of 30 Eaten by a tiger shark 48 Disease

the Western North Atlantic. U.S. Department of Commerce NOAA Technical Memorandum NMFS- SEFSC-455, 343 pp. 91 Hypothermic stunning

Wynne, K. & M. Schwartz. 1999. Guide to Marine Eggs that survive stage Four: 27, 99

Mammals & Turtles of the U.S. Atlantic & Gulf of Mexico. Rhode Island Sea Grant, Narragansett, RI. 114 pp. STAGE FIVE 0.02% overall survivorship (2 out of 1000) Adult stage 3,7 survive (refer to Stage Five directions on page 8 for explanation)

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SEA TURTLE WEB RESOURCES

Track a Turtle http://139.70.40.46/loggrhd.htm

S EA TURTLE SCIENCE http://www.marine-ed.org/bridge/survivor.pdf Contacts: ayers@vims.edu & petrone@vims.edu

Satellite Turtle Tracking http://www.seaturtle.org/tracking

GENERAL BIOLOGY EuroTurtle http://www.euroturtle.org/

CONSERVATION Sea Turtle Protection and Conservation http://www.nmfs.noaa.gov/pr/species/turtles/

All About Turtles http://octopus.gma.org/turtles/index.html

Biology and Conservation of Sea Turtles http://marinediscovery.arizona.edu/lessonsF00/ brittle_stars/2.html

Sea Turtles http://www.seaworld.org/animal-info/info-books/ sea-turtle/index.htm

SPECIES SPECIFIC Teaching Guide-Saving the Sea Turtles http://teacher.scholastic.com/activities/explorer/

Caribbean http://www.cccturtle.org

Conservation/Sea Turtle Survival League

oceanlife/main.asp? template=field_sites&article=turtles_field1

Ocean Planet: Stranded Along the Coast http://www.smithsonianeducation.org/educators/ lesson_plans/ocean/stranded/essay.html

Leatherback Turtle Hurdle Game http://teacher.scholastic.com/activities/explorer/ oceanlife/main.asp?template=show&article=turtle

Sea Turtles Coloring Book http://www.yoto98.noaa.gov/books/seaturtles/

Green Sea Turtles http://earthtrust.org/wlcurric/turtles.html

seatur1.htm

Leatherback Sea Turtle

NESTING Spotlight on a Scientist: Kate Mansfield, Sea Turtle

http://www.tpwd.state.tx.us/huntwild/wild/ species/lethback/

Biologist http://www.marine-ed.org/bridge/ index_mansfield.html

Kemp’s Ridley Sea Turtle http://www.tpwd.state.tx.us/huntwild/wild/ species/ridley/

See Turtles Nest! See Turtles Hatch! http://www.marine-ed.org/bridge/ index_archive0700.html

GLOSSARY Desiccation - the process of drying up

Watamu Turtle Watch http://www.watamuturtles.com

Escarpment - a long cliff or steep slope separating two comparatively level or more gently sloping surfaces and resulting from Folly Beach Turtle Watch Program

erosion or faulting http://www.follyturtles.com/tracks.html

Gyre - a giant circular oceanic surface current TRACKING Tracking Sea Turtles http://octopus.gma.org/space1/turtles.html

Hypothermic - having a subnormal body temperature

Sea Turtle Survival League Educator's Guide http://www.cccturtle.org/eduform.htm

Pelagic - of, relating to, or living or occurring in the open sea

SEA TURTLE SCIENCE BY MUSICK & LAWRENCE • 2003 11