César Andrés Castillo, 1980-2023: A Remembrance

César A. Castillo with one of his many natural history projects. Photo: Wendy Castillo

César Andrés Castillo, 1980-2023

A Remembrance

By Donna L. Schulman, Queens County Bird Club member

César A. Castillo, a beloved member of the City's birding community and an adjunct professor of biology and senior laboratory technician at Queens College, passed away from an illness on March 1, 2023. César was a passionate naturalist and a valued member of NYC Bird Alliance's board of directors who generously shared his love of nature with others. We are grateful to be able to share this tribute to César, penned by fellow Queens County Bird Club member Donna L. Schulman.

César Andrés Castillo first came to the attention of the Queens birding community through his eBird checklists. Someone was birding Kissena Park—a park plop in the middle of busy Flushing—and finding good birds. And sometimes, great birds: Swallow-tailed Kite on May 10, 2013. Golden Eagle on September 30, 2013. The list went on: Red-headed Woodpecker, Lark Sparrow, Blue Grosbeak, and more warblers than we ever knew stopped there… and all well-documented records that had all of us supposedly-more-experienced birders standing with our mouths open, looking at the sky, trying to see what César was seeing. 
A member of the Queens County Bird Club, César also became a sector leader on the Queens County Christmas Bird Count—a new sector pieced together from areas he himself proved were worth the work. He was always welcome at twitches for rare birds, because he would be able to spot the target bird, no matter how skulky. (My first memory of César is that of a tall, soft-spoken guy standing next to me in a long line of birders, searching for a Virginia’s Warbler—a “mega” find—in Alley Pond Park. César patiently pointed out the tiny bird in dense shrubbery, over and over.)
But César was more than a finder of “good birds.” He was a kind, generous, smart soul, a caring participant in our birding community who happily shared his finds and always greeted you in the field with a smile and had a good bird, insect, or blooming tree to point out. He was a member of the board of NYC Bird Alliance, where he advocated for diversity and inclusion. 
Occasionally, I would see César with his Queens College biology students. In fact, that’s how I last saw him, at Meadow Lake in Flushing Meadows Corona Park, surrounded by young people. He was showing them something on the shore, probably not a bird because it was a not-very-birdy November afternoon, and then a bird nest in a small tree near the boathouse. The students were engaged and happy, and so was César. It was an all-too-brief glimpse into a side of his life most of his fellow birders didn’t get to see: César in a more formal teaching role, which obviously fit him as well as birding did.
César was a scientist. His bird sightings were precisely recorded in eBird (with notes!) and in iNaturalist, where he documented at the research-grade level 3,693 species of birds, insects, herps, moss, and plants: 1,929 species in Queens County, 2,122 species in New York City, and 2,488 species in New York State. These are significant contributions to both community-science databases, particularly to iNaturalist. There are many people out there observing birds, but how many have also identified 28 species of lichen in their home county? 
César was an excellent photographer, and a look at the albums on his Flickr site gives another glimpse into his broad nature interests: warblers (534 photos and 1 video); frogs; mosses and liverworts; heaths; UBOs (Unidentified Botanical Objects); birds of Ethiopia—this is just a small sample of his subjects. Many of his New York City bird photos illustrate NYC Bird Alliance’s soon-to-be-published bilingual Spanish-English field guide, Las Aves de la Ciudad de Nueva York / The Birds of New York City. His Yellow Warbler is featured on the cover.
Ironically, perhaps, César did not identify himself as an expert. On his eBird personal page, he wrote, “I can't seem to focus on any one type of life form. Fish, plants (living and fossil, tropical or temperate), algae, Amphibians, Insects, Reptiles, Mammals, Birds, Protists. I guess I know a little about a lot of things.”  On his iNaturalist page he wrote, “Trained in botany as a grad student, and consider myself a Naturalist in training for the rest of my life.” 
The birding and nature communities lost a wealth of knowledge when César passed away, and a good person. It is our fortune that he leaves us with some of that knowledge, good memories, and an inspiring life. 

NYC Bird Alliance extends its sympathies to César’s wife, Wendy Castillo, and their three young children, Giselle, Elyse, and Santiago. We hope you’ll consider donating to this GoFundMe set up to support César’s family through this difficult time.