Friday, January 15, 2016

FERAL GEESE


Photographed on Norfolk January 2016
NOT COUNTED AS A SPECIES ON THE AUSTRALIAN LIST

Submission No 809: Greylag Goose Anser anser Nofolk Island. Free ranging and breeding for at least 20 years prior to January 2014.

This case is unusual in that it deals with an introduced species rather than a rarity. It deals with the possibility of including Greylag Goose Anser anser as a new feral species to the Australian List. The submitter intentionally investigated evidence to determine if the geese were feral or not on Norfolk Island. 

After investigation and personal observation it was concluded that the birds on Norfolk Island were feral and had been breeding at the locality for more than 10 years. In total at least 43 birds were present at Kingston Common, six at the Watermill Pond, and at least 32 at the Missionary Pond on Norfolk Island.  A photograph taken by B. Dawson was provided along with a table of sightings dating back to the year 2000.

Members were divided in their opinion on how to treat this case. Five voted against acceptance and three voted in favour.  Those that voted against did so because: (a) it was quite clear the birds were not Greylag Geese but rather just Domestic Geese (with hybrid origins) with a hint of “greylag” in the mix, given that many were clearly oversize and white in colour; (b) even though they may be breeding outside captivity they are not necessarily free flying; and (c) we cannot be sure that these birds derive 100% from Greylag Geese as some appear to have ties closer to Swan Goose Anser cygnoides. A hybrid origin would preclude the population from being treated as a ‘species’ on the Australian checklist. Understandably, the submission makes no attempt to identify the goose strain.

As pointed out within the submission the most common criteria for declaring a species as feral is ‘a period of 10 years breeding in a wild state without dependency from humans’. Admittedly Greylag Geese are considered feral in New Zealand, but there is little information available on their origins or ecology there (Heather & Robertson 2006).

This is the first time that BARC has considered a submission dealing with the potential establishment of a feral population. 


Verdict: Not Accepted




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