How Do Baby Turtles Know To Go To The Ocean
Baby sea turtles hatch out of eggs and must leave their nest in order to survive.
Baby turtles have a very hard time finding food while they are still inside the egg, so once they emerge from the nests, it’s imperative that they find something to eat immediately.
After hatching, new-born babies need to be able to swim away from danger or towards potential prey as quickly as possible.
The fastest way for them to get what they need is by going straight to the water where there are plenty of fish to hunt.
Once they reach the edge of the pond or lake, they can either dive into the water right after birth or continue swimming around until they locate an area with lots of vegetation (plants).
They use this vegetation as a sort of landmark to guide them back to open water.
If you’ve ever seen turtles wiggling on the shoreline trying to decide whether or not to head in or out of the water then you might understand why they don’t want to stay put too long.
It takes quite some practice before these little creatures learn how to navigate without any help from their parents.
Their mothers lay many hundreds of thousands of eggs during one nesting season and most of those eggs won’t make it through the first few weeks alive.
Only a small percentage of the hatchlings actually live past 3 days.
That means that only the strongest and healthiest ones end up surviving.
So if you were looking at all the turtle tracks in your backyard pond or beach, you’d see this pattern repeated over and over again:
More males than females because the female turtles spend much more time incubating their eggs;
Fewer babies who survived because they’re slower swimmers than the fast boys and girls;
Finally, a smaller number of adults because most of the healthy young animals didn’t make it through weeding week.
Once baby turtles have made their choice between land or water, they’ll begin exploring each option with increasing confidence.
First they’ll try to follow their noses toward the smell of the water but since they aren’t really capable of distinguishing smells yet, they may simply keep moving forward until they happen upon a body of water.
When they arrive at the water, they’ll start investigating everything within sight, including rocks, grasses and other debris.
As soon as they spot anything edible, even mud, they’ll grab onto it like it was gold! How do baby turtles know to run to the water?
Baby turtles grow faster than almost every other animal except birds and fish–they mature in less than four years’ time compared to upwards of twenty years for full grown human beings.
During that brief span of time, however, growth rate accelerates dramatically.
Hatchlings average eight pounds in weight whereas fully grown adults weigh anywhere between 140 lbs. and 250 lbs.
Yet despite their impressive size increases, babies tend to prefer smaller prey such as snails, worms and mosquito larvae.
Compared to adults, baby turtles consume fewer calories per day and require proportionally less protein.
Adult turtles feed heavily on shellfish and crustaceans while eggs are consumed exclusively.
Since baby turtles generally swim towards rather than away from danger, their survival rates are surprisingly good considering their diminutive size.
Most hatchlings do manage to escape harm if they crawl into cracks or crevices, hide among dense foliage or float downstream.
Many of them survive to become successful adults.
On the whole, turtles fare better now than ever before thanks to conservation efforts aimed at protecting the natural resources upon which turtles depend for food and nesting sites.
Although populations continue to decline due to loss of wetlands, pollution and invasive species, research indicates that turtles respond positively to increased protection and preservation efforts.
At least seven distinct subspecies of freshwater turtles and fourteen marine reptile species inhabit regions extending from North America to Madagascar.
Why do turtles go to the sea?
Unlike tortoises, crocodiles and sharks, turtles don’t breathe air.
Instead, they rely on their lungs to extract oxygen from water.
Young turtles are able to perform this task themselves early in development.
Afterward, they gradually lose the ability and turn to their gills.
Like all vertebrates, turtles possess paired nostrils located on either side of the skull.
One pair leads to the mouth opening and the other opens independently into the nasal cavity.
All turtles have multiple openings leading to the nostril cavities and one or more breathing slits.
Breathing chambers open outward into the tracheal tree.
Air enters the respiratory chamber via an opening located at the base of the tongue and travels past the vocal cords to fill the lung cavity.
Because turtles cannot hold their breath, they breathe in spurts and commonly stop moving momentarily whenever they feel threatened.
Unlike other aquatic organisms, turtles aren’t capable of holding their breath indefinitely.
Therefore, it makes sense that when confronted by approaching enemies, turtles retreat into deep water where they can wait out the threat.
Only when the predator moves away, do turtles emerge and begin searching for safer grounds.
In addition to being a great defense mechanism, returning to the ocean represents a significant challenge.
Land animals usually travel uphill, but turtles face a daunting journey across open water.
Using internal physiological processes, newborn hatchlings slowly adjust to changes in salinity.
Gradually lowering their blood osmotic pressure causes gradual accumulation of sodium potassium ions inside cells.
This process, called osmoregulation, enables turtles to tolerate drastic variations in environmental osmolality.
By contrast, migrating from the ocean to land involves rapid change from hypertonic to isotonic media and requires considerable capacity for volume regulation.
Waterlogged kidneys enable turtles to excrete excess fluid back into the bloodstream.
Unfortunately, the same mechanisms that protect hatchlings from dehydration prove dangerous for adult turtles living in brackish water or marshes.
Acclimated to higher osmolarity, adult turtles experience severe hyponatraemia (low plasma concentrations of sodium) whenever exposed to unusually salty environments.