Become acquainted with the 250 species of birds dwelling in the city’s five boroughs, and learn about balancing city life with concern for the environment. The Earthwatch Institute increases the eco-friendliness of wildlife exploration by offsetting the carbon emissions of their trips and day-to-day operations through the purchase of carbon credits or emission reduction credits.

Trip Tip: Snag a reservation at Candle Café (1307 Third Avenue; 212/472-0970;, dinner for two $60), one of New York’s Certified Green Restaurants.
Luxury Level: Travelers will stay in historic farmhouses on the Marshlands Conservancy, a 137-acre wildlife sanctuary in Rye, New York. No modern glamour here, but you’ll certainly experience rustic relaxation.

Key Wildlife and Environmental Conservation: Earthwatch Institute; 800/776-0188;; nine-day trips from $1,746 per person; various dates from May 2008-August 2008.