What to Bring

Passport
A photocopy of your passport.
Money and credit card (many places will not accept traveler's checks)
Long pants, lightweight
Summer weather clothing
Lightweight clothing for cover-up
Hat with brim, and sunglasses
Field shoes (light hiking boots, running shoes; must be able to endure mud)
Walking shoes
Sandals (for beach and pool)
Socks (lots of pairs, they get wet often)
Rain jacket or poncho
Bathing suit & beach towel
Sunscreen (absolute must)
Insect repellent (high DEET content)
Binoculars
Field guides (depending on your interests)
Camera, film, digital cards
Personal Items (shampoo, soap, deodorant, etc)
Hair dryer OK
Prescription medications (be sure to tell me if these are vital to your health!)
Notebook, pens, pencils
Day pack (or fanny pack, almost a necessity)
Travel alarm clock (the howler monkeys do a good job, but they are not perfect)
Snorkeling mask, fins and snorkel
Clothes to wear when snorkeling (cover legs and arms to protect from sunburn)
Flashlight (extra batteries)
Zip-Lock bags (several sizes, really handy for samples, keeping camera, binocs dry)
Light jacket or sweatshirt (it can be cool in San Jose and on volcano)
Extra glasses or contacts