Female turtles lay their eggs in holes they dig on sandy beaches and then return to the sea. The eggs hatch in about 60 days, usually at night to give the tiny babies the best chance to avoid predators as they scurry down the beach and into the sea.
Sea turtles hatch throughout the year but mostly in summer.
Hatchlings use a carbuncle (temporary egg tooth) to help break open the shell.
After hatching, the young turtles may take 3 to 7 days to dig their way to the surface.
Hatchlings usually wait until night to emerge from the nest. Emerging at night reduces exposure to daytime predators. Studies have shown that some nests will produce hatchlings on more than one night.
For most sea turtle species, undisturbed nests can have more than 90% of the clutch successfully hatch. Nests disturbed by humans or animal predators tend to have a 25% or even much lower success rate.
Reaching the ocean
There are several theories as to how hatchlings find the sea.
- Hatchlings may discriminate light intensities and head for the greater light intensity of the open horizon.
- During the crawl to the sea, the hatchling may set an internal magnetic compass, which it uses for navigation away from the beach.
When a hatchling reaches the surf, it dives into a wave and rides the undertow out to sea.
- A “swim frenzy” of continuous swimming takes place for about 24 to 48 hours after the hatchling enters the water.
- This frantic activity gets the young turtle into deeper water, where it is less vulnerable to predators.
- There have been reports of swimming hatchlings diving straight down when birds and even airplanes appear overhead. This diving behavior may be a behavioral adaptation for avoiding predation by birds.
- Past the surf zone, hatchlings use their internal magnetic compass for orientation.
The”lost” years.
After entering the ocean, the hatchlings of many species of sea turtles are rarely seen for 1 to 3 years. These are referred to as the “lost years.”
Researchers generally agree that most hatchlings spend their first few years living an oceanic existence before appearing in coastal areas. Although the migratory patterns of the young turtles during the first year has long been a puzzle, most researchers believe that they ride prevailing surface currents, situating themselves in floating seaweed where they are can find food.
Research suggests that flatback hatchlings do not go through an oceanic phase. Evidence shows that the young turtles remain inshore following the initial swim frenzy. Most remain within 15 km (9.3 miles) of land.
Credit : Sea world parks & entertainments
Picture Credit : Google