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26 September 2018 Alexander Cruz, 1941–2018
Catherine P. Ortega, Yan Linhart, Carl E. Bock
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Alexander Cruz, Fellow of the American Ornithologists' Union (AOU; now American Ornithological Society), died on May 15, 2018, in Boulder, Colorado, after a brief battle with pancreatic cancer. He will be remembered as an outstanding professor, mentor, and avian researcher in the Department of Ecology and Evolutionary Biology at the University of Colorado (CU). His boundless energy, contagious passion for science and conservation, and dedication to diversity touched thousands of students and colleagues both in the United States and abroad, especially in the West Indies.

Alex was born in New York City to Puerto Rican parents, Florentino Cruz and María Luisa Cruz, on July 12, 1941, and grew up speaking both English and Spanish at home. His father was a canary enthusiast, and Alex could not recall a life without birds. That early exposure sparked an interest in wild birds and other urban wildlife. A junior high school biology teacher in New York encouraged Alex, at the age of 14, to begin his lifelong interest in watching birds. Alex would also search vacant, weedy lots in the city for insects and anything else he could find. His interest in insects was keen enough that he knew them by scientific name—rather startling for a kid growing up in a neighborhood with street gangs. He recalled that gangs didn't hassle him because spouting scientific names made him an unlikely candidate for recruitment, or because the gang members sensed he would “go somewhere” and just “let him go.” Frequent visits to relatives in Puerto Rico furthered his blossoming interests, offering Alex opportunities not available in the dense urban setting of his home. Birds were both more abundant and easier to observe on Puerto Rico than in New York City. Those early experiences played a crucial role in Alex's later interests in tropical ecology and island biogeography.

While an undergraduate at City University of New York (CUNY), Alex developed a close friendship with Matt Cormons, who would become a naturalist and artist. Each had a profound influence on the other, and they spent many weekends during and after college bird watching together. After completing his B.S. in biology at CUNY in 1964, Alex worked as a microbiologist for the New York City Health Department for five years. He and Cormons continued their bird excursions in New York, across the country, and in Mexico. Hungry for more than their jobs offered, they encouraged each other to attend graduate school. Cormons recalls that Alex “was the incentive for me to also attend grad school, which I am very grateful for. We were definitely a positive influence on each other.”

Alexander Cruz enjoying Magellanic Penguins in Chile, 2016. Photo courtesy of Alex Cruz, Jr.


Alex obtained a Ford Foundation Fellowship when he enrolled in the Department of Zoology and Ecology at the University of Florida in 1968. He returned to his beloved West Indies to study Jamaican Woodpeckers, which resulted in his 1973 Ph.D. dissertation, “Ecology and behavior of the Jamaican Woodpecker (Melanerpes radiolatus).” His graduate advisor, the late David W. Johnston, also had a strong research interest in birds of the West Indies.

After being hired as an assistant professor at CU in 1973, Alex worked his way through the ranks, becoming a professor in 1989. In 1990, the university appointed him as a President's Teaching Scholar. In addition to his teaching and research duties, Alex served as assistant dean (1990–1995) and associate dean (1995–2000) of the Graduate School. In that capacity, he played a major role in helping the campus become a more ethnically and culturally diverse environment, one that welcomed students from the Caribbean, Latin America, and elsewhere. From 2000 until he retired in December 2017, Alex was an adjunct curator at the CU Museum of Natural History.

In addition to Cormons and his advisor, numerous other individuals influenced the path of Alex's career, including Archie Carr (a herpetologist who served on his graduate committee), Oliver Austin, Pierce Brodkorb, George Cornwell, Eugene Eisenmann, and Thomas Patton. While birds remained Alex's primary focus throughout his life, he marveled at all life forms, large and small, extant and extinct. His research interests included interactions among organisms within communities, which were increasingly fascinating to Alex. He expanded his research interests to as many areas as he could get away with, while maintaining control of his research program. He is probably most well known for his contributions to our knowledge of brood parasitism in birds, particularly Shiny and Brown-headed cowbirds. His other research interests included ecology of avian communities along the Front Range of Colorado, ecology and conservation of island birds, behavioral evolution of Village Weavers on Hispaniola, sexual selection in fish, brood parasitism by the African Cuckoo Catfish, herpetofauna, and the impact of noise pollution on bird communities.

Alex was the major advisor for 21 Ph.D. students and 23 master's students and served on a total of 110 graduate committees. To our knowledge, all of his graduate students moved into influential positions, and many have received prestigious awards and honors, both while in graduate school and during their postgraduate careers. Also dedicated to undergraduate students, Alex supervised 39 undergraduate honors theses and more than 350 students conducting various independent research projects. Alex's commitment to sharing his research resulted in over 140 published papers, at least 40 technical reports, and over 150 presentations at scientific meetings.

On arriving at CU in 1973, the 32-year-old Alex made an immediate splash on the predominantly Caucasian campus, not only because of his Latino background but by his thorough dedication to increasing educational opportunities and a high quality of life for a diversity of students. Throughout his career, he actively recruited underrepresented students, particularly from Puerto Rico. Alex's minority graduate students have been exceptionally successful in their careers; all finished their graduate studies and have taken on academic positions or other professional careers, and many have received prominent awards.

Working long hours, often until near dawn, Alex's commitment to his department and university was exemplary. He served on many standing and ad hoc committees throughout his academic career, at both university and departmental levels. As an important contributor to its teaching, research, and mentoring programs, Alex helped advance his department into the accomplished group it is today, and his service at the university level was equally stellar. In just the last 15 years of his career, Alex served on 16 university committees, many of which included multiple years of service. He was particularly active on the committees that involved promoting diversity. In addition to mentoring students in his department, he devoted time to mentoring students for science and minority programs at the university level. During his academic career, Alex taught a total of 11 courses in addition to graduate seminars and independent research.

Somehow, Alex managed to find time for the community. Early in his career, he was popular at his sons' schools for giving engaging presentations. Later in his career, when he maintained an impressive fish lab at the university, with around a hundred or more tanks, he hosted educational tours for over 600 K–12 students and their teachers. He mentored high school students and gave presentations at public schools. He served as a scientific trustee at the Denver Zoo and as a consultant to the Department of Natural and Environmental Resources Program of Puerto Rico, where he shared his expertise on the endangered Yellow-shouldered Blackbird and Shiny Cowbird. Alex regularly reviewed article submissions for at least 20 journals, including The Auk. He also reviewed grant proposals for the National Science Foundation and the National Geographic Society.

Over his career, Alex received at least 25 awards, honors, and recognitions, including CU's Outstanding Undergraduate Research Mentor Award (2014); the Ronald Ryder Award for Distinguished Service and Scholarly Contributions to Colorado Field Ornithology (2010); the Hazel Barnes Award, CU's highest teaching and research award (2006); and Elective Member (1976) and Fellow (1992) of the AOU.

Alex was a family man and loved to travel. His children grew up enjoying more international travel than most Americans experience in a lifetime. In addition to their trips to national parks within the United States, they traveled to Mexico, various countries in Central and South America, the West Indies, Southeast Asia, Australia, Europe, and Iceland. Alex must have been a most inspiring and knowledgeable travel guide for his family.

Alex was one of the most genuinely caring and compassionate people ever to walk the earth. Always a gentleman, he had a fine sense of humor and accepted everyone for who they were. He never tried to change people, only seeking to enhance their experiences and opportunities. Without being a martyr, Alex regularly placed other people's needs before his own. Because he provided a safe environment for his students that promoted creative thinking free from criticism, he had a happy lab, filled with laughter and lively conversations, often in mixed English and Spanish.

Although his 76 years on earth seemed too brief, and he passed away so quickly after retirement, Alex spent his life doing exactly what he wanted to do. He pursued and achieved his dreams and lived a rewarding life filled with enriching experiences. His favorite group of birds was woodpeckers. Some of the last “life birds” he observed were woodpeckers, including Magellanic Woodpecker in Chile, with his son Alex, Jr.; Black Woodpecker in Spain, with his son Nicholas; and Black-backed Woodpecker in Minnesota, with Alex, Jr.

Alex had four children: Eric, Alex, Jr., Nicholas, and Isabella. He is survived by Alex, Jr., Nicholas, and Isabella. Alex will be missed by all who were touched by his enthusiasm, kindness, and generosity.

© 2018 American Ornithological Society.
Catherine P. Ortega, Yan Linhart, and Carl E. Bock "Alexander Cruz, 1941–2018," The Auk 135(4), 1182-1184, (26 September 2018).
Published: 26 September 2018
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