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Mystery Shark Egg

A fun aspect of visiting The Trust Family Foundation Shark and Ray Touch Tank is the possibility of getting to see shark eggs. Many shark species give birth to live young, and some species create internal eggs that then hatch inside of the mother. Some species, though, like those in our exhibit, lay good old-fashioned eggs. Just as they would in the wild, many of the sharks here lay their eggs among clusters of mangrove roots, which makes it hard for larger predators to get at them.


Shark eggs in the touch tank

You may have seen similar--but empty--egg cases wash up on local beaches. Those eggs are laid by small sharks called dogfish, and also by fish called skates. Skates are similar to stingrays, one of the differences being that stingrays give birth to live young while most skate species lay eggs. Many people call these egg pouches 'Mermaid's Purses.'

Sometimes the shark eggs in our exhibit aren't fertile, but the sharks lay them anyway, the same way chickens would. Unlike chicken eggs, though, shark egg cases are clear enough that sometimes you can see right inside:


A (probably) infertile shark egg in the touch tank

The yolk, which is clearly visible, feeds the developing shark embro until the shark is big enough to emerge. Although the bamboo shark egg pictured above is likely not fertile, every now and again we find an egg that is. Can any Touch Tank veterans tell which of the exhibit's shark species will emerge from the egg below? Check back sometime in the next two weeks to find out.


Can you guess what species of touch tank shark is growing up inside this egg case? 

Continue on to Part II!

5 comments:

  1. Looks like a Zebra shark egg. Very cool!

    ReplyDelete
  2. that is sick i want to go to see it

    ReplyDelete