When I was in my early 20s, I had an influential experience with bird nests.

I was an undergraduate studying zoology at Cal Polypamona in Southern California.

At the edge of campus, there was a little remnant patch of scrub habitat,

the sort of habitat that, for thousands of years,

blanketed the coastal lowlands of Southern California,

before the landscape was transformed into the nightmare of urban sprawl that it is today.

This patch had some western sycamore and native walnut trees overshadowing shrubs like

Toyon, Blue Elder, and Black Sage, and some coastal prickly pear cactus in there, too.

I was becoming more and more intrigued by birds back then, so I volunteered for a research project

that my ornithology professor was running. The bird of interest was the cactus wren,

Kampilorinkus Brunea Kapilis.

It's a large, noisy wren with a spotted breast, a streaky back, and lots of personality.

The goal of my professor's project was to gather data on cactus wren nests, to find any general

patterns in nest site selection, nest orientation, stuff like that. Honestly, this was a long time

ago and I don't remember all the details. But I do remember loving the experience of going out into that scrub habitat in the early morning,

breathing the cool air, redolent with the spicy sweet scent of sage, and hearing the cactus wrens

and other birds singing. I had my data sheet on a clipboard, and I'd go check on the cactus

wrens and their nests to record data.

These wrens use dried grasses and sticks to build an enclosed spherical nest with a side

entrance hole. And just where do they like to place these nests? You guessed it in cactus.

Cactus wrens prefer to tuck their nests in among the wicked spines of dense cactus. At the habitat at my college, the only cactus option was coastal

prickly pear. You can imagine that this is a pretty safe place to raise your chicks,

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