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Rainforests of the World 

April 25, 2010

Have you ever seen 800 babies all at once??

Last fall our orb weaver spider (Nephila clavipes) on the Costa Rica level of the rainforest laid several egg cases. And recently one of the egg cases hatched with approximately 800 offspring! They’re tough to photograph, but below is a picture of a group of the hatchlings at a couple days old:

orb weaver BABIES

Photo by: Rachael Tom

Orb weavers in the Americas have an interesting natural history. They range from southeast United States (North Carolina to Texas) through Central America into the warmer parts of South America. In the U.S. they are a seasonal species, hatching from previously laid egg cases in April/May and then dying after they reproduce in Oct/Nov. In more tropical climes, they typically live 2-3 years. Here is a photo of an adult taken near Puerto Viejo de Sarapiqui, Costa Rica:

orb weaver adult

Photo by: Eric Hupperts

With a body length of two inches and ~4 inches with their legs, these are good sized spiders. They have extremely strong silk with a tensile strength six times that of steel! There are species of Nephila throughout the world’s tropical areas. Come visit our 800 baby orb weaver spiders next time you are at the Academy. They can be seen on the third (Costa Rica) level hiding out in the terrarium accross from the elevator doors. Here’s what one of the little cuties looked like on Thursday the 22nd of April:

baby orbs-4

Photo by: Rachael Tom

Filed under: Insects & Arachnids — rainforest1 @ 12:31 pm


  1. omg thats a really cool spider and wow 800 babies at once!!!!! in the pic it showed a person holding the spider in their hand!!! i wonder if its poisons but it has really cute colors i wonder where they live???

    Comment by marissa...luv stevenn — April 29, 2010 @ 4:29 pm

  2. omg the Cal academy of science looks really cool and good for people to learn. im thinking about going this summer because i luv science and i want to learn alot more about science because i want to be a science teacher when im older!!! its cool how all those animals, rainforests,and lots of other things are there in a building!!! i would have to say my fav part of the academy is the real fish and just looks like its outside i think its really cool and im looking forward to going there and having lots of fun!!!

    Comment by marissa...luv stevenn — April 29, 2010 @ 4:37 pm

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