Tuesday, 7 April 2015

Gannet Colony – Portland Victoria

The Australasian Gannet is a common and well-known seabird along the southern half of the Australian coast and in New Zealand. Strikingly beautiful birds, their pursuit of small fish is spectacular to watch as they dive into the sea at great speed, headfirst like arrows, and completely submerge.
Australasian Gannet at Point Danger.
In Australia Gannets breed at six offshore locations including rocks, islands and a navigation platform in Port Phillip Bay, and since 1996 one (the only) mainland location at Point Danger near Portland.
The mainland colony is an overflow from the nearby offshore colony at Lawrence Rocks where it is estimated 6,000 pairs of Gannets currently nest each year. This colony at Point Danger really only works through human intervention, that is by the maintenance of a predator (fox) exclusion fence.
A committee of management supported by a number of volunteers and organisations manage the site. The first fence erected was a metal chain-wire mesh fence, the same as that commonly used as security fencing. This fence, while still in place, has now been replaced by a more effective and easier to maintain plastic electric fence, which encloses a far smaller area of the point.
Mainland Gannet colony at Point Danger, Portland. The main 6000 pair colony is located on Lawrence Rocks visible out to sea. Note a section of the electric fence in foreground.
A large notice board at the end of the road access provides a good description of Gannets and the Point Danger breeding colony.
Impressive information board at viewing area on Point Danger.
In recent years some closely related Cape Gannets from Africa have turned up at the colony and interbred with the local species much to the delight of Australian bird twitchers.
When we visited the colony in early April at the end of the August-March breeding season, there were about 60 Gannets present including about 6 juvenile birds.  There were no immature birds present so it is assumed these have taken off to an independent life away from the colony. Research has shown young birds after leaving the colony head west, some travelling as far as the Tropic of Capricorn on the WA coast, returning to their birth colony after 3 to 4 years away.
These photos taken at the colony include some flight shots of one bird that circled the colony many times before finally landing. I can imagine this would be a testing exercise when the colony is full and every available nesting site is occupied by a potentially hostile breeding pair defending their precious space. However there was plenty of room when we were there. Perhaps the circling bird’s tentative approach was ingrained or it may have simply been enjoying effortless flight on a moderately stiff onshore breeze?
There were mostly adult birds resting at the colony.
There were about 6 juvenile birds in the colony. The soft charcoal plumage is striking.
I am not sure if these birds are flying yet, they look fully fledged and capable.

This bird circled the colony many times before coming in to land.
The same bird as above. Note the streamlined bill and body and imagine the wings tucked in
and the bird spearing through the ocean surface at great velocity.
The bird finally came in to land - this is the start of the approach - into the wind of course.
Landing gear out with subtle wing control in the brisk wind to maintain correct attitude.
Touch down, a perfect landing with a number of birds looking on.
Once landed, and as the large wings were folded away, the bird looked back as if to see
how the resting birds reacted to the show!
While the Point Danger Gannet colony is, in the context of the overall Australian Gannet population and the much larger breeding sites, a somewhat irrelevant and artificial anomaly, it is a good place to easily observe breeding gannets up close. It is an interesting tourist site that helps inform people about our magnificent wildlife and is an excellent example of what can be achieved by a diverse range of groups/organisations working together to protect our native fauna.
If you happen to be in the Portland area during spring or summer a visit to the Gannet colony at Point Danger is definitely worthwhile.
PS. Some information gleaned from here and there regarding A Gannets:
They tend to mate for life and live for 30 years or more.
New Zealand A Gannets migrate across the Tasman Sea to Australia when they greatly outnumber the Aussie birds (I am sure the Kiwis would love this fact).
They are sedentary, migratory and dispersive while some are present at colonies all year. It is unclear how all these options work across the whole population and at the individual level, over time and over the life span of an individual.
Are all birds sedentary, migratory and dispersive at some stage in their lives or is it just that some individuals mostly stay and others move?
Gannets are birds of coastal waters and do not range far out to sea and across oceans like albatross and other pelagic species.

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