Trumpeter Swan, Indian Lake, Denville, NJ, Jan. 26, 2014 (photo by J. Klizas)
If one travels among the many lakes of Morris County and the few in Somerset County, there is the slim possibility of seeing a Trumpeter Swan (TRUS). Do not get excited. It has been my onerous duty on many occasions to inform a puzzled and/or excited observer that the TRUS they saw is not of genuinely wild origin.
Here is the story in brief. In approximately 2009, local birders began noticing a pair of TRUS on a private pond on Lloyd Road in Bernardsville. This caused some excitement for a brief time but the swans’ fearless approach to Homo sapiens signaled that they were not of wild stock. Sure enough, it was learned that the swans were a gift to the property owners (one can go online and purchase Trumpeter Swans and other waterfowl, for a price). That settled that, until the next year, 2010, when the captive pair gave birth to six cygnets. Jim Gilbert has a wonderful photo of the brood in his Flickr photostream, here.
A visit to the pond in 2011 revealed that three of the youngsters had left. Eventually, one was seen regularly at the Friends Blind at the Wildlife Observation center of the Great Swamp NWR. It kept company with a Tundra Swan into May of that year. Another TRUS appeared at Lake Parsippany for one day. The mocosocoBirds post for that sighting and links to photos of the Great Swamp swans is here. Later that winter, a TRUS spent time at Indian Lake in Denville. Two were on Leddell’s Pond in Mendham Twp. in 2012. One TRUS spent most of the summer of 2013 at Mt. Hope Lake. Currently, one is the small unfrozen section of Indian Lake in Denville – and on it goes.
Three immature Trumpeters reported in 2014 at Lake Assunpink, Monmouth County have been validated, or confirmed, on eBird. Keep in mind, this does not mean they are accepted as individuals of wild origin. That is for the New Jersey Bird Record Committee to decide.
As for any Morris and Somerset sightings, they will NOT be confirmed on eBird. The Bernardsville captive pair have poisoned the local waters, if you will. A discussion with an eBird administrator agrees that they should not be validated. This default action pertains to the Morris and Somerset County TRUS only.
Do we know where all of these TRUS come from? Of course not. Without an identification band to determine its origin, a TRUS could have come from anywhere. This does not mean they should go unreported. It is of great scientific and research value to track the appearances of these birds. Invalidating a record on eBird only means it will not show in reports. It does not delete the record. It does not imply the observer is a bad person. On the contrary, if TRUS become established in New Jersey at a later date, current records may be revisited. Remember that although many people use eBird as a listing software, it is primarily a research tool of enormous magnitude. Do not fear reporting!
mocosocoBirds 
Jon’s post raises this question for me: How many generations does it take for a bird found in these two counties, and thus likely to have descended from this purchased pair, to be considered wild? If these six cygnets, now grown up, produce offspring by breeding with each other (would that be possible…or is there filial recognition and natural eschewing of incest in birds which would prevent that?), would those offspring be considered of natural provenance? Or if, by strange chance, one of these six encountered a truly wild Trumpeter, chose that wild bird as a mate, and produced offspring, would THOSE progency be considered wild?
Here is the ABA Criteria for Determining Establishment of Exotics, although it is still up to the individual state Bird Record Committee to determine if these criteria are met:
http://listing.aba.org/criteria-determining-establishment-exotics/
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