Impacts of Artificial Lighting on the Survival of

Sea Turtles

Michael Slattery

Why should it matter?• All 6 species of sea turtle that nest in

North America are either Endangered or Threatened.

Nesting• Generally they nest every 1-3 years• Females always return to the beach

from which they hatched• They may lay multiple clutches.• Hatch after 6-13 weeks of incubation

Nest survival• Where they get deposited• Predation• Disease

Hatching success• 80% of the eggs hatch• Upon emergence they’ll orient themselves

to the brightest light field. • Only 1 in 1000 hatchlings make it to

adulthood and reproduce

Human activities can compound the problem

• 53% of the US. Population lives within 60 miles of the Coast.

• This requires significant infrastructure.• The beaches are very economically

valuable to the US.

Several possible outcomes• Depends on the magnitude of

brightness• Pick the wrong way

– Sunrise– Swimming pools– Cars– Domestic animals– Natural predators

What do you think?• Low natural success• Human impact

– Redirect lights– Lower intensities

• Something should be done