Where the Desert Meets the Sea: Isla Alcatraz

One of my most frequented research sites is a small island located less than a mile from the mainland of Bahía Kino. While Isla Alcatraz only has a surface area of 1.44km², it is one of the most important bird areas in the Gulf of California. The island is utilized by over 50 different bird species and boasts thirteen different species of nesting birds. Additionally, it is home to 60 plant species, 6 reptile species of which 3 are endemic, 1 endemic bat species, at least 88 species of invertebrates, and supports marine mammals offshore. The island is composed mostly of a mountainous rocky cliff with one flat desert area to the east. It is part of the “Islands of the Gulf of California Reserve,” and as such is protected from development. However, it still faces threats from shrimp trawlers offshore, fishermen, and visitors that leave trash, disturb animals, or step on nests.

Isla Alcatraz has the largest colony of nesting Double Crested Cormorants (DCCO) in the Gulf of California. The DCCO nest along the crevices of the cliffs in small colonies. They begin nesting in late September, peak in December (about 2000 nests!), and taper out over the spring months. Part of my monitoring consists of recording the number of DCCO nests, and later I will be conducting a productivity study. The island is divided into sections to simplify surveying. One side of the island can only be counted from the panga (boat) because of the high cliffs, and the other side I traverse by foot. This seems like a simple enough job, but the island likes to throw challenges in your way.

First of all, this island was initially referred to as “Hell” by one of the teaching assistants. I thought this might be a little harsh, but then I decided that for most people (like you Mom) “Hell” would be a pretty accurate description. The first thing you notice up close to the island is the strong smell of bird guano. Since thousands of birds use this area daily, it smells pretty bad. Next, while surveying the island you are completely exposed to the elements, so at this time of year, it is blazing hot. Then you must maneuver your way around squawking/pooping birds (like Yellow Footed Gulls) through prickly cacti to reach the survey spots. Finally, as you survey, these little bugs who are about three times the size of a fruit fly, called bobitos, surround and land all over you. Luckily they don’t bite, but they are attracted to moisture since there is no source of fresh water on the island. This means, as you are sweating profusely trying to count hundreds of nests, little bugs are crawling all over you and flying in your ears, eyes, and up your nose!

But if you can get past all of that, it is an incredible ecosystem. I am amazed how much life the island can support and it is one of my favorite places to work.