The ABJ trails superlatives behind him. As a 1987 G Pool chick, he was one of the first three loons ever banded at Seney NWR. He was the first color-marked juvenile to return to the refuge as a breeding adult , and the first to ultimately acquire his own nesting territory and nesting partner. Since that time, he has formed half of the most productive pairing at Seney. As of 2007, he was the oldest common loon of known age  in the world.
As with all banded loons who have been monitored for many years, the ABJ can be regarded as both a contributor to a broader database of information and as an individual with a distinctive life history that can, at times, assume to contours of personality. In his case, it is difficult not to gravitate toward the latter perspective…
He’s ambitious: while most Seney pairs limit their territories to one pool, or even to a portion of one, the ABJ and his mate  have carved out a domain that incorporates one and a half pools. In certain years, it has swollen to two and a half. As territorial intruders are an omnipresent fixture of refuge life, the defense of this much turf balanced, as it must be, between the demands of procreation and parenting is no mean feat.
He’s a gentle giant: as a large male 5.1 kg in 2006, among the heaviest banded loons in Michigan he can generally discourage and dispatch challengers before an encounter turns overtly antagonistic, and oftentimes eschews vocalizations and other overt warnings in favor of a behavioral nonchalance… interlopers land in expectation of alarmed attention, and instead receive a disinterested snubbing that effectively signals pal, you’re not much of a threat to me.
He’s a good father: in years of successful nesting, he in contrast to many refuge parents, including his mate rarely leaves his offspring unattended in order to participate in social gatherings upon foreign pools. And his filial devotion is not only pronounced but protracted: he’s almost invariably the last adult to depart from Seney in the fall. A common September sight is that of the ABJ, the base of his bill heralding the onset of winter plumage, tending to the bottomless appetite of his offspring even as the remainder of the refuge’s juveniles have been left to fend for themselves.
The primary goal in delaying his voyage, of course, is to better prepare his progeny for their own unchaperoned migration toward the ocean, and in this respect his tendencies seem to have served him well: in 2007 three of his former offspring hatched in 1999, 2000 and 2001, respectively, and all males were active on the refuge. Two held their own territories, and one the eldest reproduced successfully for the first time. The ABJ was a grandpa at twenty. As a luminary of our long-term investigation into aspects of loon population dynamics such as longevity, and as part of a color-marked population that returns with an annual fidelity of 97%, there’s reason to both hope and expect that before his refuge tenure expires he’ll add a few greats to his grandfatherly appellation.
 Color-marked loon chicks who reappeared as adults after a multi-year adolescence on southern waters were originally dubbed ABJs, an acronym for the somewhat cumbersome term Adult, Banded (as a ) Juvenile. As the first such returnee, the 1987 G Pool chick was also granted the term as a moniker. Almost two decades later, through some combination of tradition and inertia, this ambiguity persists… the twenty year-old F/E east male of Seney NWR is the ABJ, while any previously banded chick who materializes as a breeding adult is an ABJ.
 The “known age” qualifier is necessitated by the ongoing presence of Seney loons who were banded as adults during the earliest years of the project. Because their age was unknown at the time of capture, we can only state that they are at least x years old. For example, the D Pool female Scarecrow was color-marked on that territory in 1989 (her nineteen years of uninterrupted occupation is a record); as she was no less than three at the time, she was at least 22 in 2007. Owing to this uncertainty, the data provided by ABJs like the ABJ is somewhat preferable, as it entails a complete life history.