Have you seen the Spanish WT Magazine? It appears the full name of Gerard, the last name is Hertel. I dont know why in the english version they are hiding the last name of Gerard, maybe they dont want that we ask him about the article.
Thank you elkatire1980 for that valuable piece of information. (His surname is included in some of the other European language versions too.)
Yes, it's weird that the English version does not have his last name which means something's fishy. It took a little while to dig around but ...
EUREKA!
... now it's all become clear.
From a cached page (2003) about alumni from the University of Wisconsin:
Gerard Hertel PhD'75 retired in January 2001 after thirty-five years with the USDA Forest Service, but he's certainly been busy since then. Hertel writes that he "now spends his time teaching the Bible as one of Jehovah's Witnesses; getting to know his wife of thirty-three years, Bobbie, a little better; and serving as an adjunct professor in the Department of Biology at West Chester [Pennsylvania] University," in his home community.