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Sea Turtles OLD

Sea Turtle Research and Monitoring Progam

Sea turtles are among the world’s oldest creatures. These ancient reptiles have long fascinated people around the world. On Sanibel and Captiva, where the beaches provide a subtropical nesting area for threatened loggerhead and endangered green turtles, more than 100 island residents volunteer each summer as part of the Conservation Foundation’s Sea Turtle Research and Monitoring Program. The program operates under a permit from the Florida Fish and Wildlife Conservation Commission.

Each day during nesting season, May to October, the 18 miles of Gulf beaches from the Sanibel Lighthouse to the tip of Captiva are checked beginning at dawn. In some areas, volunteers walk designated zones of beach. On other stretches, the patrol is done by beach vehicle. Nests are identified and marked for monitoring and protection. Later in the season new hatches are evaluated and recorded. The statewide collection of data helps promote programs that improve the chances for sea turtles to survive.

Among other components of SCCF’s sea turtle program are projects ensuring that beach habitat is suitable for nesting and the co-ordination of data collection on local sea turtle strandings.

You can contact the Sea Turtle office by e-mail: seaturtle@sccf.org

Sea Turtle Trivia

• Sea turtles live their entire life in the ocean except when the female comes ashore to lay eggs. Males rarely leave the water.
• Adults can grow to more than three feet in length and weigh between 250 and 400 pounds.
• Female loggerheads emerge at night to lay from 50 to 175 leathery, ping-pong ball sized eggs. The eggs will hatch 55 to 60 days later.
• Temperature plays a role in whether eggs develop as male or female. Warmer temperatures tend to mean more females, cooler more males.
• Hatchlings emerge from the nest at night and use the light of the horizon to orient themselves to the water.
• Hatchlings weigh less than one ounce and are two inches long.
• Sea turtles have great underwater vision but are nearsighted out of the water.

What You Can Do

• Keep lights near the beaches off or shielded from May through October. Artificial lighting from buildings or flashlights confuses nesting females and hatchlings. Disoriented by light, baby turtles wander away from the water and die.
• Keep the beach and water free of litter. Sea turtle deaths have been due to trash such as balloons, plastic bags, and styrofoam mistaken for food.
• Remove furniture and other items from the beach at night. These obstacles may cause a female turtle to return to the water without laying her eggs. They may also block a hatchling’s route to the water causing it to remain on the beach and dehydrate.
• Stay clear of sea turtles and any marked nesting areas. It is a federal offense to disturb or interfere with a nest. It is also illegal to disturb a nesting turtle with lights or noise. It is against the law to have in your possession eggs or any part of a turtle, such as skull, bones, or carapace or to retain any threatened or endangered sea turtle hatchlings.
• Honor the leash law. All dogs on the beach must be on a leash and cannot be allowed to disturb nesting turtles or hatchlings.
• If you find lost hatchlings, please call the Sanibel-Captiva Conservation Foundation at 472-2329 and a licensed volunteer will pick up the turtles. In the meantime, place them in a dry container with a little moist sand in the bottom and hold them in a shaded area.
• If you see a stranded turtle, check to see if there are orange marks painted on its shell. If so, this stranding has already been reported to the Sanibel Captiva Conservation Foundation’s sea turtle program. If this is a new stranding, call SCCF at 239-472-3817, ext. 228, Monday – Friday. On weekends, report the stranding to the Sanibel Police at 239-472-3111.
• Adopt your own nest to help defray the costs of SCCF’s Sea Turtle Research and Monitoring Program.

Statistics

Every turtle season is cause for excitement. With it comes anticipation of what the season might bring and the opportunity to give something back to the Earth. The opening days provide a fertile field for speculation. The turtles may bring a record-breaking season or a more usual one.

2008

2007

The nesting numbers overall on Sanibel and Captiva continued the decline of recent years. Sanibel was up a bit from last year, by 12% in the west end and nearly double on the east end. Captiva, however, was down 35%. All areas of the islands were hit with periods of unusually high tides due to Tropical storm Barry in June and Hurricane Dean in August, which covered or washed out a number of nests.

Sanibel’s west end beaches were selected as part of a genetics-sampling project being undertaken by a student at the University of Georgia. The project goal is to determine what are the similarities and differences in the genetic stocks of loggerheads nesting in many different areas. While conducting the post-hatch dig, permittees collected either a flipper from a dead hatchling or an eggshell; samples were placed in a vial of ethanol and labeled with date, nest number and position.

2006

Turtle season finished with a total of 216 nests on Sanibel and Captiva, only a few nests more than the 2005 season. This is a decline of approximately 50 % since 1992, when the Conservation Foundation took over the sea turtle monitoring program from Caretta Research. The most productive year was 1995, with more than 534 nests recorded.

2005

The 2005 season followed the recent downward trend in the number of nests, totaling about 50 fewer than in 2004. The high tides and winds from Hurricane Dennis completely washed out more than 40 nests and dumped sand over others, from a few inches to three feet deep. The additional sand cuts off the oxygen to the eggs and may make it difficult for hatchlings to emerge even if they do hatch. Repeated wash-overs by high tides have produced nests with larger numbers of unhatched eggs and with more hatchlings found dead in the nests. On this coast, usually 80 percent of eggs laid hatch; by September, however, the percentage was one-half of that.

2004

The 2004 sea turtle season came in slowly and started out well but the monitoring program ended for the season on Aug. 13 with the arrival of Hurricane Charley.

False crawls on the west end were almost double the number of nests. Captiva had the lowest number of false crawls, with one fewer than the number of nests.

Driving the west end a week after Charley was an awesome experience. The beaches from Tarpon Bay to Bowman's Beach were beautifully flat with an extra helping of lovely white Gulf sand. One nest in the Gulf Shores/Gulf Pines area had two stakes left standing with about four feet of sand covering the original nest level. With the extra sand washed in, not a single nest stake was found anywhere else. Those nests in the mid-beach area were totally washed out; those higher up the beach were covered with four to six feet of sand.

Because identification markers were swept away, we lost track of approximately 90 nests on the west end, about 31 on the east end, and an estimated 32 on Captiva.

In addition to a much larger number of false crawls than normal, attributed to very dry sand in the early summer, there were no nests or eggs destroyed by raccoons, while the 2003 season had more than 40 nests partially or completely destroyed by them.

In the final beach run, a week after Charley, there was one turtle nest laid the previous night: a large, perfect, almost textbook-case nest in the middle of the tracks of multiple vehicles patrolling the beaches. Turtle life goes on as it has for millions of years, with or without our help.

2003

In 2003, weather came in with a bang on June 26 with several consecutive days of high tides that covered nests. This probably accounted to some degree for the greater number of nests with higher percentages of unhatched eggs. The next period of high tides and nests under water came late in the season, September 6, and washed out 10 nests.

Every year, raccoons feast on turtle eggs and this year, despite screens over the nests, they enjoyed more than in previous years. Ghost crabs, which usually prey on hatchlings, were responsible for taking a small number. Fire ants prey on nests, either before or after the hatchlings leave them. Fortunately, these three predators together usually affect only a small percentage of eggs and hatchlings.

Sanibel and Captiva's 2003 total is 322 - more than in 2001 or 2002 but less than nest numbers in 1999 and 2000. The general trend for sea turtle nests is downward and the East Coast records its 2003 nests as the fewest in history.

2002

Nests for the 2002 Sanibel-Captiva turtle season fell to 279, the first time the number has dropped below 300 since 1995. Extremely high tides over several days in both June and July resulted in more nests than usual that did not hatch at all. Very few nests were totally washed away, but more were covered over with sand to the extent that hatchlings could not find their way out. In nests that did produce hatchlings, there were larger numbers of unhatched eggs.