Kemps Ridley Sea Turtle Lepidochelys kempii

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Kemps Ridley Sea TurtleLepidochelys kempii

• 1992 Recovery Plan

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Population Status

• 1947- Photographic evidence suggests 40,000
  nesting females in one day on beach (Rancho
  Nuevo) in Northwest Mexico
• 1968 The number of nesting females at a single
  site declined to 5,000
• 1991 The number of nesting females at a single
  site was reduced to 200.

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Do the Math

• What percent of nesting females remained in 1991
  from the original estimation in 1947?
• 1/2 of 1 percent

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Why is this significant?

• Because nearly the entire adult female population
  nests at a single locality, it is possible to
  estimate the females reproductive population by
  counting all the nests laid at this site.

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Who is not being counted?

• Males, immature turtles, and the sparce breeding
  groups of female turtles that are dispersed
  between Padre Island, TX and Isla Aguada,
  Campeche.
• Males and juveniles do not frequent beaches and
  therefore are difficult to count, currently
  females are the only measure of the turtle
  population.

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Endangered Status

• Kemps Ridleys were listed as endangered in the
  United States on December 2, 1970.
• Internationally, L. kempii are considered the
  most endangered sea turtle.
• Kemps Ridleys are listed in Appendix 1 of CITES

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Historic Threats

• Man induced mortality is to blame for the
  observed modern decline of the species.
• In Texas, early settlers began to exploit coastal
  turtles. There were once turtle canneries along
  the Texas coast.
• Eggs were harvested at Rancho Nuevo from the
  1940s to the 1960s

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Nesting Threats

• Human development along beach fronts
• Armoring, nourishment, or cleaning of beaches
• Motorized equipment along the beach crush buried
  eggs
• Collection of corals is leading to increased
  flooding which places eggs at risk for drowning.

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Threats to the Marine Environment

• Commercial Fisheries incidental take by the
  shrimping industry is the largest source of
  mortality for L. kempii
• Turtles are held under water by trawl nets and
  drown because they can not reach the surface to
  breathe.

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Threats from the Oil Industry

• The two primary feeding grounds for adult L.
  kempii are near major off-shore and on-shore oil
  exploration.
• The beach at Nuevo Rancho was affected by a large
  oil spill in 1979.
• Oil has been documented in lab studies to cause
  skin alteration, decreased blood glucose, and
  increased white blood cell counts in L. kempii.

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Threats from Floating Debris

• Plastics, monofilament, discarded netting are
  known to entangle turtles resulting in a death
  trap.
• Ingestion of plastic, rubber, fishing line, and
  hooks, tar cellophane, rope, string, wax,
  Stryofoam, charcoal, aluminum cans, and cigarette
  filters has occurred in sea turtles.
• Digestive tract impaction and toxic absorption
  are the 2 major environmental risks to L. kempii.
  

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Threats from Dredging

• Dredging operations affect L. kempii through
  incidental take and by degrading the habitat.
• Incidental take of Ridleys has been documented
  with hopper dredges.
• In addition to direct take, channelization of the
  inshore and nearshore areas can degrade the
  foraging and migratory habitat through soil
  dumping, degraded water quality, and altered
  current flow.

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Conservation History

• Mexico passed laws to protect Rancho Nuevo beach
  in 1966.
• From 1966-1977 an average of 23,000 hatchlings
  were released annually.
• From 1978-today, 54,000 hatchlings are released
  annually.
• When nests are laid, they are then moved the same
  day to fenced and guarded corals.

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Conservation Data
Kemp's ridley turtle nesting at Rancho Nuevo
beach, Tamaulipas, México.
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Turtle Excluder Device

• In 1987, the United States required all shrimp
  fleet vessels to install TEDs.

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MARPOL

• Treaty restricts the discharge of plastics and
  other garbage into the marine environment.
• Because of the vast amount of trash discarded in
  the Gulf of Mexico, it was added as a special
  area under Anex V of MARPOL in 1992

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Captive Breeding Programs

• Using head-started turtles that have been
  retained until adulthood, living hatchlings have
  been produced.
• Fertility rates in captive breeding are lower
  than found in natural settings.
• The practice of imprinting was used to encourage
  hatchlings to return to South Padre Island
  Seashore.

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Goal of 1992 Recovery Plan

• To bring L. kempii to form endangered to
  threatened status utilizing the following
  criteria
• Complete and active protection of nesting beaches
  and surrounding waters
• Elimination of mortality from incidental catch in
  commercial shrimping in the US and Mexico through
  the use of TEDs.
• Attain a population of at least 10,000 females
• Successfully implement all priority one recovery
  tasks

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Protect and Manage Nesting Habitats

• Encourage Mexico to expand and codify the Kemps
  Ridley National Reserve at Rancho Nuevo.
• Encourage Mexico to restrict development that may
  degrade the nesting habitat.
• Identify additional nesting beaches in Mexico
• Manage other nesting beaches

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Protect and Manage the Marine Environment

• Identify important marine habitat
• Identify threats to marine habitat
• Prevent destruction of marine habitat

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Protect and manage populations on nesting beaches

• Protect nesting females
• Protect nests and increase production
• Protect and increase viability of hatchlings
• Monitor population trends

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Protect population in the marine environment

• Determine distribution and abundance
• Determine habitat use by neonates/pelagic
  juveniles
• Determine seasonal use of nearshore habitat by
  juveniles/subadults
• Determine migratory paths and foraging areas
• Determine significance of the northeast and
  mid-Atlantic juveniles

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Monitor and reduce mortality from fisheries

• Enforce TED regulation and expand use
• Define law and enforce the existing prohibition
  of trawling within the Rancho Nuevo Reserve.
• Encourage and assist Mexico to use TEDs
• Maintain the Sea Turtle Stranding and Salvage
  Network

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Other Efforts for Conservation

• Monitor and reduce impacts from petroleum
  activities
• Monitor and reduce impacts from dredging
  activities
• Reduce oceanic pollution
• Maintain captive stocks
• Increase education programs

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Your assignment

• Choose one part of the recovery plan proposed in
  1992.
• Research to find out if the plan was ever
  implemented.
• If the plan was implemented was it successful?
• If the plan was not implemented why not?

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Source

• Recovery Plan for the Kemps Ridley Sea Turtle
  Lepidochelys kempii created by the US Department
  of Commerce, National Oceanic and Atmospheric
  Administration, National Marine Fisheries
  Service, US Department of the Interior, and the
  US Fish and Wildlife Service, 1992
  http//www.nmfs.noaa.gov/pr/pdfs/recovery/turtle_k
  empsridley.pdf