The Colorado River, in contrast, is much more green, and can also run chocolate-milk brown during the monsoon season. We were lucky enough to catch a blue heron fishing (he was successful) along the bank. Other wildlife spotted on this trip (though not successfully photographed) include a healthy number of bats and lizards in addition to a rarely seen (for us anyhow) desert fox!
If you are interested in making the visit to Havasu Canyon yourself, you can find information and make your reservations with the Havasupai Tribe. Peak visitation is likely during the summer months - though I personally prefer the shoulder seasons when there are fewer visitors (and temperatures are more suitable for hiking). For those who don't care to hike in or pack in your own gear, it is possible to ride a helicopter or hire a horse service to carry your pack(s) in or out of the canyon.